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Sample records for message passing algorithms

  1. Discrete geometric analysis of message passing algorithm on graphs

    NASA Astrophysics Data System (ADS)

    Watanabe, Yusuke

    2010-04-01

    We often encounter probability distributions given as unnormalized products of non-negative functions. The factorization structures are represented by hypergraphs called factor graphs. Such distributions appear in various fields, including statistics, artificial intelligence, statistical physics, error correcting codes, etc. Given such a distribution, computations of marginal distributions and the normalization constant are often required. However, they are computationally intractable because of their computational costs. One successful approximation method is Loopy Belief Propagation (LBP) algorithm. The focus of this thesis is an analysis of the LBP algorithm. If the factor graph is a tree, i.e. having no cycle, the algorithm gives the exact quantities. If the factor graph has cycles, however, the LBP algorithm does not give exact results and possibly exhibits oscillatory and non-convergent behaviors. The thematic question of this thesis is "How the behaviors of the LBP algorithm are affected by the discrete geometry of the factor graph?" The primary contribution of this thesis is the discovery of a formula that establishes the relation between the LBP, the Bethe free energy and the graph zeta function. This formula provides new techniques for analysis of the LBP algorithm, connecting properties of the graph and of the LBP and the Bethe free energy. We demonstrate applications of the techniques to several problems including (non) convexity of the Bethe free energy, the uniqueness and stability of the LBP fixed point. We also discuss the loop series initiated by Chertkov and Chernyak. The loop series is a subgraph expansion of the normalization constant, or partition function, and reflects the graph geometry. We investigate theoretical natures of the series. Moreover, we show a partial connection between the loop series and the graph zeta function.

  2. Algorithms for parallel flow solvers on message passing architectures

    NASA Technical Reports Server (NTRS)

    Vanderwijngaart, Rob F.

    1995-01-01

    The purpose of this project has been to identify and test suitable technologies for implementation of fluid flow solvers -- possibly coupled with structures and heat equation solvers -- on MIMD parallel computers. In the course of this investigation much attention has been paid to efficient domain decomposition strategies for ADI-type algorithms. Multi-partitioning derives its efficiency from the assignment of several blocks of grid points to each processor in the parallel computer. A coarse-grain parallelism is obtained, and a near-perfect load balance results. In uni-partitioning every processor receives responsibility for exactly one block of grid points instead of several. This necessitates fine-grain pipelined program execution in order to obtain a reasonable load balance. Although fine-grain parallelism is less desirable on many systems, especially high-latency networks of workstations, uni-partition methods are still in wide use in production codes for flow problems. Consequently, it remains important to achieve good efficiency with this technique that has essentially been superseded by multi-partitioning for parallel ADI-type algorithms. Another reason for the concentration on improving the performance of pipeline methods is their applicability in other types of flow solver kernels with stronger implied data dependence. Analytical expressions can be derived for the size of the dynamic load imbalance incurred in traditional pipelines. From these it can be determined what is the optimal first-processor retardation that leads to the shortest total completion time for the pipeline process. Theoretical predictions of pipeline performance with and without optimization match experimental observations on the iPSC/860 very well. Analysis of pipeline performance also highlights the effect of uncareful grid partitioning in flow solvers that employ pipeline algorithms. If grid blocks at boundaries are not at least as large in the wall-normal direction as those

  3. Message-Passing Algorithms for Inference and Optimization. "Belief Propagation" and "Divide and Concur"

    NASA Astrophysics Data System (ADS)

    Yedidia, Jonathan S.

    2011-11-01

    Message-passing algorithms can solve a wide variety of optimization, inference, and constraint satisfaction problems. The algorithms operate on factor graphs that visually represent and specify the structure of the problems. After describing some of their applications, I survey the family of belief propagation (BP) algorithms, beginning with a detailed description of the min-sum algorithm and its exactness on tree factor graphs, and then turning to a variety of more sophisticated BP algorithms, including free-energy based BP algorithms, "splitting" BP algorithms that generalize "tree-reweighted" BP, and the various BP algorithms that have been proposed to deal with problems with continuous variables. The Divide and Concur (DC) algorithm is a projection-based constraint satisfaction algorithm that deals naturally with continuous variables, and converges to exact answers for problems where the solution sets of the constraints are convex. I show how it exploits the "difference-map" dynamics to avoid traps that cause more naive alternating projection algorithms to fail for non-convex problems, and explain that it is a message-passing algorithm that can also be applied to optimization problems. The BP and DC algorithms are compared, both in terms of their fundamental justifications and their strengths and weaknesses.

  4. Message passing in PUMA

    SciTech Connect

    Maccabe, A.B. |; Wheat, S.R.

    1993-05-01

    This paper provides an overview of the message passing primitives provided by PUMA (Performance-oriented, User-managed Messaging Architecture). Message passing in PUMA is based on the concept of a portal--an opening in the address space of an application process. Once an application process has established a portal, other processes can write values into the memory associated with the portal using a simple send operation. Because messages are written directly into the address space of the receiving process, there is not need to buffer messages in the PUMA kernel. This simplifies the design of the kernel, increasing its reliability and portability. Moreover, because messages are mapped directly into the address space of the application process, the application can manage the messages that it receives without needing direct support from the kernel.

  5. Cooperative Localization for Mobile Networks: A Distributed Belief Propagation–Mean Field Message Passing Algorithm

    NASA Astrophysics Data System (ADS)

    Cakmak, Burak; Urup, Daniel N.; Meyer, Florian; Pedersen, Troels; Fleury, Bernard H.; Hlawatsch, Franz

    2016-06-01

    We propose a hybrid message passing method for distributed cooperative localization and tracking of mobile agents. Belief propagation and mean field message passing are employed for, respectively, the motion-related and measurement-related part of the factor graph. Using a Gaussian belief approximation, only three real values per message passing iteration have to be broadcast to neighboring agents. Despite these very low communication requirements, the estimation accuracy can be comparable to that of particle-based belief propagation.

  6. Streaming data analytics via message passing with application to graph algorithms

    DOE PAGESBeta

    Plimpton, Steven J.; Shead, Tim

    2014-05-06

    The need to process streaming data, which arrives continuously at high-volume in real-time, arises in a variety of contexts including data produced by experiments, collections of environmental or network sensors, and running simulations. Streaming data can also be formulated as queries or transactions which operate on a large dynamic data store, e.g. a distributed database. We describe a lightweight, portable framework named PHISH which enables a set of independent processes to compute on a stream of data in a distributed-memory parallel manner. Datums are routed between processes in patterns defined by the application. PHISH can run on top of eithermore » message-passing via MPI or sockets via ZMQ. The former means streaming computations can be run on any parallel machine which supports MPI; the latter allows them to run on a heterogeneous, geographically dispersed network of machines. We illustrate how PHISH can support streaming MapReduce operations, and describe streaming versions of three algorithms for large, sparse graph analytics: triangle enumeration, subgraph isomorphism matching, and connected component finding. Lastly, we also provide benchmark timings for MPI versus socket performance of several kernel operations useful in streaming algorithms.« less

  7. Streaming data analytics via message passing with application to graph algorithms

    SciTech Connect

    Plimpton, Steven J.; Shead, Tim

    2014-05-06

    The need to process streaming data, which arrives continuously at high-volume in real-time, arises in a variety of contexts including data produced by experiments, collections of environmental or network sensors, and running simulations. Streaming data can also be formulated as queries or transactions which operate on a large dynamic data store, e.g. a distributed database. We describe a lightweight, portable framework named PHISH which enables a set of independent processes to compute on a stream of data in a distributed-memory parallel manner. Datums are routed between processes in patterns defined by the application. PHISH can run on top of either message-passing via MPI or sockets via ZMQ. The former means streaming computations can be run on any parallel machine which supports MPI; the latter allows them to run on a heterogeneous, geographically dispersed network of machines. We illustrate how PHISH can support streaming MapReduce operations, and describe streaming versions of three algorithms for large, sparse graph analytics: triangle enumeration, subgraph isomorphism matching, and connected component finding. Lastly, we also provide benchmark timings for MPI versus socket performance of several kernel operations useful in streaming algorithms.

  8. The ACL Message Passing Library

    SciTech Connect

    Painter, J.; McCormick, P.; Krogh, M.; Hansen, C.; Colin de Verdiere, G.

    1995-09-01

    This paper presents the ACL (Advanced Computing Lab) Message Passing Library. It is a high throughput, low latency communications library, based on Thinking Machines Corp.`s CMMD, upon which message passing applications can be built. The library has been implemented on the Cray T3D, Thinking Machines CM-5, SGI workstations, and on top of PVM.

  9. Formal Analysis of Message Passing

    NASA Astrophysics Data System (ADS)

    Siegel, Stephen F.; Gopalakrishnan, Ganesh

    The message passing paradigm underlies many important families of programs - for instance programs in the area of high performance computing that support science and engineering research. Unfortunately, very few formal methods researchers are involved in developing formal analysis tools and techniques for message passing programs. This paper summarizes research being done in our groups in support of this area, specifically with respect to the Message Passing Interface. We emphasize the need for specialized varieties of many familiar notions such as deadlock detection, race analysis, symmetry analysis, partial order reduction, static analysis and symbolic reasoning support. Since these issues are harbingers of those being faced in multicore programming, the time is ripe to build a critical mass of researchers working in this area.

  10. Reduction of the effects of the communication delays in scientific algorithms on message passing MIMD architectures

    NASA Technical Reports Server (NTRS)

    Saltz, J. H.; Naik, V. K.; Nicol, D. M.

    1986-01-01

    The efficient implementation of algorithms on multiprocessor machines requires that the effects of communication delays be minimized. The effects of these delays on the performance of a model problem on a hypercube multiprocessor architecture is investigated and methods are developed for increasing algorithm efficiency. The model problem under investigation is the solution by red-black Successive Over Relaxation YOUN71 of the heat equation; most of the techniques described here also apply equally well to the solution of elliptic partial differential equations by red-black or multicolor SOR methods. Methods for reducing communication traffic and overhead on a multiprocessor are identified and results of testing these methods on the Intel iPSC Hypercube reported. Methods for partitioning a problem's domain across processors, for reducing communication traffic during a global convergence check, for reducing the number of global convergence checks employed during an iteration, and for concurrently iterating on multiple time-steps in a time-dependent problem. Empirical results show that use of these models can markedly reduce a numewrical problem's execution time.

  11. Gene-network inference by message passing

    NASA Astrophysics Data System (ADS)

    Braunstein, A.; Pagnani, A.; Weigt, M.; Zecchina, R.

    2008-01-01

    The inference of gene-regulatory processes from gene-expression data belongs to the major challenges of computational systems biology. Here we address the problem from a statistical-physics perspective and develop a message-passing algorithm which is able to infer sparse, directed and combinatorial regulatory mechanisms. Using the replica technique, the algorithmic performance can be characterized analytically for artificially generated data. The algorithm is applied to genome-wide expression data of baker's yeast under various environmental conditions. We find clear cases of combinatorial control, and enrichment in common functional annotations of regulated genes and their regulators.

  12. Can rare SAT formulae be easily recognized? On the efficiency of message-passing algorithms for K-SAT at large clause-to-variable ratios

    NASA Astrophysics Data System (ADS)

    Altarelli, Fabrizio; Monasson, Rémi; Zamponi, Francesco

    2007-02-01

    For large clause-to-variable ratios, typical K-SAT instances drawn from the uniform distribution have no solution. We argue, based on statistical mechanics calculations using the replica and cavity methods, that rare satisfiable instances from the uniform distribution are very similar to typical instances drawn from the so-called planted distribution, where instances are chosen uniformly between the ones that admit a given solution. It then follows, from a recent article by Feige, Mossel and Vilenchik (2006 Complete convergence of message passing algorithms for some satisfiability problems Proc. Random 2006 pp 339-50), that these rare instances can be easily recognized (in O(log N) time and with probability close to 1) by a simple message-passing algorithm.

  13. CT reconstruction via denoising approximate message passing

    NASA Astrophysics Data System (ADS)

    Perelli, Alessandro; Lexa, Michael A.; Can, Ali; Davies, Mike E.

    2016-05-01

    In this paper, we adapt and apply a compressed sensing based reconstruction algorithm to the problem of computed tomography reconstruction for luggage inspection. Specifically, we propose a variant of the denoising generalized approximate message passing (D-GAMP) algorithm and compare its performance to the performance of traditional filtered back projection and to a penalized weighted least squares (PWLS) based reconstruction method. D-GAMP is an iterative algorithm that at each iteration estimates the conditional probability of the image given the measurements and employs a non-linear "denoising" function which implicitly imposes an image prior. Results on real baggage show that D-GAMP is well-suited to limited-view acquisitions.

  14. Message Passing Framework for Globally Interconnected Clusters

    NASA Astrophysics Data System (ADS)

    Hafeez, M.; Asghar, S.; Malik, U. A.; Rehman, A.; Riaz, N.

    2011-12-01

    In prevailing technology trends it is apparent that the network requirements and technologies will advance in future. Therefore the need of High Performance Computing (HPC) based implementation for interconnecting clusters is comprehensible for scalability of clusters. Grid computing provides global infrastructure of interconnecting clusters consisting of dispersed computing resources over Internet. On the other hand the leading model for HPC programming is Message Passing Interface (MPI). As compared to Grid computing, MPI is better suited for solving most of the complex computational problems. MPI itself is restricted to a single cluster. It does not support message passing over the internet to use the computing resources of different clusters in an optimal way. We propose a model that provides message passing capabilities between parallel applications over the internet. The proposed model is based on Architecture for Java Universal Message Passing (A-JUMP) framework and Enterprise Service Bus (ESB) named as High Performance Computing Bus. The HPC Bus is built using ActiveMQ. HPC Bus is responsible for communication and message passing in an asynchronous manner. Asynchronous mode of communication offers an assurance for message delivery as well as a fault tolerance mechanism for message passing. The idea presented in this paper effectively utilizes wide-area intercluster networks. It also provides scheduling, dynamic resource discovery and allocation, and sub-clustering of resources for different jobs. Performance analysis and comparison study of the proposed framework with P2P-MPI are also presented in this paper.

  15. Tracking particles by passing messages between images

    SciTech Connect

    Chertkov, Michael; Kroc, Lukas; Zdeborova, Lenka; Krakala, Florent; Vergassola, M

    2009-01-01

    Methods to extract information from the tracking of mobile objects/particles have broad interest in biological and physical sciences. Techniques based on the simple criterion of proximity in time-consecutive snapshots are useful to identify the trajectories of the particles. However, they become problematic as the motility and/or the density of the particles increases because of the uncertainties on the trajectories that particles have followed during the acquisition time of the images. Here, we report efficient methods for learning parameters of the dynamics of the particles from their positions in time-consecutive images. Our algorithm belongs to the class of message-passing algorithms, also known in computer science, information theory and statistical physics under the name of Belief Propagation (BP). The algorithm is distributed, thus allowing parallel implementation suitable for computations on multiple machines without significant inter-machine overhead. We test our method on the model example of particle tracking in turbulent flows, which is particularly challenging due to the strong transport that those flows produce. Our numerical experiments show that the BP algorithm compares in quality with exact Markov Chain Monte-Carlo algorithms, yet BP is far superior in speed. We also suggest and analyze a random-distance model that provides theoretical justification for BP accuracy. Methods developed here systematically formulate the problem of particle tracking and provide fast and reliable tools for its extensive range of applications.

  16. Direct message passing for hybrid Bayesian networks and performance analysis

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Chang, K. C.

    2010-04-01

    Probabilistic inference for hybrid Bayesian networks, which involves both discrete and continuous variables, has been an important research topic over the recent years. This is not only because a number of efficient inference algorithms have been developed and used maturely for simple types of networks such as pure discrete model, but also for the practical needs that continuous variables are inevitable in modeling complex systems. Pearl's message passing algorithm provides a simple framework to compute posterior distribution by propagating messages between nodes and can provides exact answer for polytree models with pure discrete or continuous variables. In addition, applying Pearl's message passing to network with loops usually converges and results in good approximation. However, for hybrid model, there is a need of a general message passing algorithm between different types of variables. In this paper, we develop a method called Direct Message Passing (DMP) for exchanging messages between discrete and continuous variables. Based on Pearl's algorithm, we derive formulae to compute messages for variables in various dependence relationships encoded in conditional probability distributions. Mixture of Gaussian is used to represent continuous messages, with the number of mixture components up to the size of the joint state space of all discrete parents. For polytree Conditional Linear Gaussian (CLG) Bayesian network, DMP has the same computational requirements and can provide exact solution as the one obtained by the Junction Tree (JT) algorithm. However, while JT can only work for the CLG model, DMP can be applied for general nonlinear, non-Gaussian hybrid model to produce approximate solution using unscented transformation and loopy propagation. Furthermore, we can scale the algorithm by restricting the number of mixture components in the messages. Empirically, we found that the approximation errors are relatively small especially for nodes that are far away from

  17. Compressive Hyperspectral Imaging via Approximate Message Passing

    NASA Astrophysics Data System (ADS)

    Tan, Jin; Ma, Yanting; Rueda, Hoover; Baron, Dror; Arce, Gonzalo R.

    2016-03-01

    We consider a compressive hyperspectral imaging reconstruction problem, where three-dimensional spatio-spectral information about a scene is sensed by a coded aperture snapshot spectral imager (CASSI). The CASSI imaging process can be modeled as suppressing three-dimensional coded and shifted voxels and projecting these onto a two-dimensional plane, such that the number of acquired measurements is greatly reduced. On the other hand, because the measurements are highly compressive, the reconstruction process becomes challenging. We previously proposed a compressive imaging reconstruction algorithm that is applied to two-dimensional images based on the approximate message passing (AMP) framework. AMP is an iterative algorithm that can be used in signal and image reconstruction by performing denoising at each iteration. We employed an adaptive Wiener filter as the image denoiser, and called our algorithm "AMP-Wiener." In this paper, we extend AMP-Wiener to three-dimensional hyperspectral image reconstruction, and call it "AMP-3D-Wiener." Applying the AMP framework to the CASSI system is challenging, because the matrix that models the CASSI system is highly sparse, and such a matrix is not suitable to AMP and makes it difficult for AMP to converge. Therefore, we modify the adaptive Wiener filter and employ a technique called damping to solve for the divergence issue of AMP. Our approach is applied in nature, and the numerical experiments show that AMP-3D-Wiener outperforms existing widely-used algorithms such as gradient projection for sparse reconstruction (GPSR) and two-step iterative shrinkage/thresholding (TwIST) given a similar amount of runtime. Moreover, in contrast to GPSR and TwIST, AMP-3D-Wiener need not tune any parameters, which simplifies the reconstruction process.

  18. Active messages versus explicit message passing under SUNMOS

    SciTech Connect

    Riesen, R.; Wheat, S.R.; Maccabe, A.B.

    1994-07-01

    In the past few years much effort has been devoted to finding faster and more convenient ways to exchange data between nodes of massively parallel distributed memory machines. One such approach, taken by Thorsten von Eicken et al. is called Active Messages. The idea is to hide message passing latency and continue to compute while data is being sent and delivered. The authors have implemented Active Messages under SUNMOS for the Intel Paragon and performed various experiments to determine their efficiency and utility. In this paper they concentrate on the subset of the Active Message layer that is used by the implementation of the Split-C library. They compare performance to explicit message passing under SUNMOS and explore new ways to support Split-C without Active Messages. They also compare the implementation to the original one on the Thinking Machines CM-5 and try to determine what the effects of low latency and low band-width versus high latency and high bandwidth are on user codes.

  19. Message passing with parallel queue traversal

    DOEpatents

    Underwood, Keith D.; Brightwell, Ronald B.; Hemmert, K. Scott

    2012-05-01

    In message passing implementations, associative matching structures are used to permit list entries to be searched in parallel fashion, thereby avoiding the delay of linear list traversal. List management capabilities are provided to support list entry turnover semantics and priority ordering semantics.

  20. Message-passing performance of various computers

    SciTech Connect

    Dongarra, J.J.; Dunigan, T.H.

    1996-02-01

    This report compares the performance of different computer systems message passing. Latency and bandwidth are measured on Convex, Cray, IBM, Intel, KSR, Meiko, nCUBE, NEC, SGI, and TMC multiprocessors. Communication performance is contrasted with the computational power of each system. The comparison includes both shared a memory computers as well as networked workstation cluster.

  1. msg: A Message-Passing Library

    NASA Astrophysics Data System (ADS)

    Roll, J. B.; Mandel, J.

    As the foundation for the SAO MMT Instrument control software, we have developed an ASCII protocol for passing messages between client and server applications. Server interfaces are described as registered commands and published values. Clients may execute these commands and subscribe to published values. The mechanics of exchanging data between the client and server over a TCP/IP socket are handled by the library. The protocol and its implementing libraries have been designed with simplicity in mind. The simplest server can be written in three lines of code. However, we also have used the msg library to build complex systems with dozens of registered commands and hundreds of published values.

  2. Location constrained approximate message passing for compressed sensing MRI.

    PubMed

    Sung, Kyunghyun; Daniel, Bruce L; Hargreaves, Brian A

    2013-08-01

    Iterative thresholding methods have been extensively studied as faster alternatives to convex optimization methods for solving large-sized problems in compressed sensing. A novel iterative thresholding method called LCAMP (Location Constrained Approximate Message Passing) is presented for reducing computational complexity and improving reconstruction accuracy when a nonzero location (or sparse support) constraint can be obtained from view shared images. LCAMP modifies the existing approximate message passing algorithm by replacing the thresholding stage with a location constraint, which avoids adjusting regularization parameters or thresholding levels. This work is first compared with other conventional reconstruction methods using random one-dimention signals and then applied to dynamic contrast-enhanced breast magnetic resonance imaging to demonstrate the excellent reconstruction accuracy (less than 2% absolute difference) and low computation time (5-10 s using Matlab) with highly undersampled three-dimentional data (244 × 128 × 48; overall reduction factor = 10). PMID:23042658

  3. Partitioning networks into communities by message passing.

    PubMed

    Lai, Darong; Nardini, Christine; Lu, Hongtao

    2011-01-01

    Community structures are found to exist ubiquitously in a number of systems conveniently represented as complex networks. Partitioning networks into communities is thus important and crucial to both capture and simplify these systems' complexity. The prevalent and standard approach to meet this goal is related to the maximization of a quality function, modularity, which measures the goodness of a partition of a network into communities. However, it has recently been found that modularity maximization suffers from a resolution limit, which prevents its effectiveness and range of applications. Even when neglecting the resolution limit, methods designed for detecting communities in undirected networks cannot always be easily extended, and even less directly applied, to directed networks (for which specifically designed community detection methods are very limited). Furthermore, real-world networks are frequently found to possess hierarchical structure and the problem of revealing such type of structure is far from being addressed. In this paper, we propose a scheme that partitions networks into communities by electing community leaders via message passing between nodes. Using random walk on networks, this scheme derives an effective similarity measure between nodes, which is closely related to community memberships of nodes. Importantly, this approach can be applied to a very broad range of networks types. In fact, the successful validation of the proposed scheme on real and synthetic networks shows that this approach can effectively (i) address the problem of resolution limit and (ii) find communities in both directed and undirected networks within a unified framework, including revealing multiple levels of robust community partitions. PMID:21405752

  4. Hybrid approximate message passing for generalized group sparsity

    NASA Astrophysics Data System (ADS)

    Fletcher, Alyson K.; Rangan, Sundeep

    2013-09-01

    We consider the problem of estimating a group sparse vector x ∈ Rn under a generalized linear measurement model. Group sparsity of x means the activity of different components of the vector occurs in groups - a feature common in estimation problems in image processing, simultaneous sparse approximation and feature selection with grouped variables. Unfortunately, many current group sparse estimation methods require that the groups are non-overlapping. This work considers problems with what we call generalized group sparsity where the activity of the different components of x are modeled as functions of a small number of boolean latent variables. We show that this model can incorporate a large class of overlapping group sparse problems including problems in sparse multivariable polynomial regression and gene expression analysis. To estimate vectors with such group sparse structures, the paper proposes to use a recently-developed hybrid generalized approximate message passing (HyGAMP) method. Approximate message passing (AMP) refers to a class of algorithms based on Gaussian and quadratic approximations of loopy belief propagation for estimation of random vectors under linear measurements. The HyGAMP method extends the AMP framework to incorporate priors on x described by graphical models of which generalized group sparsity is a special case. We show that the HyGAMP algorithm is computationally efficient, general and offers superior performance in certain synthetic data test cases.

  5. Parallel algorithms for message decomposition

    SciTech Connect

    Teng, S.H.; Wang, B.

    1987-06-01

    The authors consider the deterministic and random parallel complexity (time and processor) of message decoding: an essential problem in communications systems and translation systems. They present an optimal parallel algorithm to decompose prefix-coded messages and uniquely decipherable-coded messages in O(n/P) time, using O(P) processors (for all P:1 less than or equal toPless than or equal ton/log n) deterministically as well as randomly on the weakest version of parallel random access machines in which concurrent read and concurrent write to a cell in the common memory are not allowed. This is done by reducing decoding to parallel finite-state automata simulation and the prefix sums.

  6. Message passing with queues and channels

    SciTech Connect

    Dozsa, Gabor J; Heidelberger, Philip; Kumar, Sameer; Ratterman, Joseph D; Steinmacher-Burow, Burkhard; Wisniewski, Robert W

    2013-09-24

    In an embodiment, a send thread receives an identifier that identifies a destination node and a pointer to data. The send thread creates a first send request in response to the receipt of the identifier and the data pointer. The send thread selects a selected channel from among a plurality of channels. The selected channel comprises a selected hand-off queue and an identification of a selected message unit. Each of the channels identifies a different message unit. The selected hand-off queue is randomly accessible. If the selected hand-off queue contains an available entry, the send thread adds the first send request to the selected hand-off queue. If the selected hand-off queue does not contain an available entry, the send thread removes a second send request from the selected hand-off queue and sends the second send request to the selected message unit.

  7. Message passing with a limited number of DMA byte counters

    DOEpatents

    Blocksome, Michael; Chen, Dong; Giampapa, Mark E.; Heidelberger, Philip; Kumar, Sameer; Parker, Jeffrey J.

    2011-10-04

    A method for passing messages in a parallel computer system constructed as a plurality of compute nodes interconnected as a network where each compute node includes a DMA engine but includes only a limited number of byte counters for tracking a number of bytes that are sent or received by the DMA engine, where the byte counters may be used in shared counter or exclusive counter modes of operation. The method includes using rendezvous protocol, a source compute node deterministically sending a request to send (RTS) message with a single RTS descriptor using an exclusive injection counter to track both the RTS message and message data to be sent in association with the RTS message, to a destination compute node such that the RTS descriptor indicates to the destination compute node that the message data will be adaptively routed to the destination node. Using one DMA FIFO at the source compute node, the RTS descriptors are maintained for rendezvous messages destined for the destination compute node to ensure proper message data ordering thereat. Using a reception counter at a DMA engine, the destination compute node tracks reception of the RTS and associated message data and sends a clear to send (CTS) message to the source node in a rendezvous protocol form of a remote get to accept the RTS message and message data and processing the remote get (CTS) by the source compute node DMA engine to provide the message data to be sent.

  8. Concurrent hypercube system with improved message passing

    NASA Technical Reports Server (NTRS)

    Peterson, John C. (Inventor); Tuazon, Jesus O. (Inventor); Lieberman, Don (Inventor); Pniel, Moshe (Inventor)

    1989-01-01

    A network of microprocessors, or nodes, are interconnected in an n-dimensional cube having bidirectional communication links along the edges of the n-dimensional cube. Each node's processor network includes an I/O subprocessor dedicated to controlling communication of message packets along a bidirectional communication link with each end thereof terminating at an I/O controlled transceiver. Transmit data lines are directly connected from a local FIFO through each node's communication link transceiver. Status and control signals from the neighboring nodes are delivered over supervisory lines to inform the local node that the neighbor node's FIFO is empty and the bidirectional link between the two nodes is idle for data communication. A clocking line between neighbors, clocks a message into an empty FIFO at a neighbor's node and vica versa. Either neighbor may acquire control over the bidirectional communication link at any time, and thus each node has circuitry for checking whether or not the communication link is busy or idle, and whether or not the receive FIFO is empty. Likewise, each node can empty its own FIFO and in turn deliver a status signal to a neighboring node indicating that the local FIFO is empty. The system includes features of automatic message rerouting, block message transfer and automatic parity checking and generation.

  9. Inference in particle tracking experiments by passing messages between images.

    PubMed

    Chertkov, M; Kroc, L; Krzakala, F; Vergassola, M; Zdeborová, L

    2010-04-27

    Methods to extract information from the tracking of mobile objects/particles have broad interest in biological and physical sciences. Techniques based on simple criteria of proximity in time-consecutive snapshots are useful to identify the trajectories of the particles. However, they become problematic as the motility and/or the density of the particles increases due to uncertainties on the trajectories that particles followed during the images' acquisition time. Here, we report an efficient method for learning parameters of the dynamics of the particles from their positions in time-consecutive images. Our algorithm belongs to the class of message-passing algorithms, known in computer science, information theory, and statistical physics as belief propagation (BP). The algorithm is distributed, thus allowing parallel implementation suitable for computations on multiple machines without significant intermachine overhead. We test our method on the model example of particle tracking in turbulent flows, which is particularly challenging due to the strong transport that those flows produce. Our numerical experiments show that the BP algorithm compares in quality with exact Markov Chain Monte Carlo algorithms, yet BP is far superior in speed. We also suggest and analyze a random distance model that provides theoretical justification for BP accuracy. Methods developed here systematically formulate the problem of particle tracking and provide fast and reliable tools for the model's extensive range of applications. PMID:20368454

  10. Study of parallel efficiency in message passing environments

    SciTech Connect

    Hanebutte, U.R.; Tatsumi, Masahiro

    1996-03-01

    A benchmark test using the Message Passing Interface (MPI, an emerging standard for writing message passing programs) has been developed, to study parallel performance in message passing environments. The test is comprised of a computational task of independent calculations followed by a round-robin data communication step. Performance data as a function of computational granularity and message passing requirements are presented for the IBM SPx at Argonne National Laboratory and for a cluster of quasi-dedicated SUN SPARC Station 20`s. In the later portion of the paper a widely accepted communication cost model combined with Amdahl`s law is used to obtain performance predictions for uneven distributed computational work loads.

  11. ACLMPL: Portable and efficient message passing for MPPs

    SciTech Connect

    Painter, J.; Krogh, M.; Hansen, C.; McCormick, P. |; de Verdiere, G.C.

    1995-09-19

    This paper presents the Advanced Computing Lab Message Passing Library (ACLMPL). Modeled after Thinking Machines Corporation`s CMMD, ACLMPL is a high throughout, low latency communications library for building message passing applications. The library has been implemented on the Cray T3D, Thinking Machines CM-5, SGI workstations, and on top of PVM. On the Cray T3D, benchmarks show ACLMPL to be 4 to 7 times faster than MPI or PVM.

  12. Message passing with queues and channels

    DOEpatents

    Dozsa, Gabor J; Heidelberger, Philip; Kumar, Sameer; Ratterman, Joseph D; Steinmacher-Burrow, Burkhard

    2013-02-19

    In an embodiment, a reception thread receives a source node identifier, a type, and a data pointer from an application and, in response, creates a receive request. If the source node identifier specifies a source node, the reception thread adds the receive request to a fast-post queue. If a message received from a network does not match a receive request on a posted queue, a polling thread adds a receive request that represents the message to an unexpected queue. If the fast-post queue contains the receive request, the polling thread removes the receive request from the fast-post queue. If the receive request that was removed from the fast-post queue does not match the receive request on the unexpected queue, the polling thread adds the receive request that was removed from the fast-post queue to the posted queue. The reception thread and the polling thread execute asynchronously from each other.

  13. Supporting the Development of Resilient Message Passing Applications using Simulation

    SciTech Connect

    Naughton, III, Thomas J; Engelmann, Christian; Vallee, Geoffroy R; Boehm, Swen

    2014-01-01

    An emerging aspect of high-performance computing (HPC) hardware/software co-design is investigating performance under failure. The work in this paper extends the Extreme-scale Simulator (xSim), which was designed for evaluating the performance of message passing interface (MPI) applications on future HPC architectures, with fault-tolerant MPI extensions proposed by the MPI Fault Tolerance Working Group. xSim permits running MPI applications with millions of concurrent MPI ranks, while observing application performance in a simulated extreme-scale system using a lightweight parallel discrete event simulation. The newly added features offer user-level failure mitigation (ULFM) extensions at the simulated MPI layer to support algorithm-based fault tolerance (ABFT). The presented solution permits investigating performance under failure and failure handling of ABFT solutions. The newly enhanced xSim is the very first performance tool that supports ULFM and ABFT.

  14. Charon Message-Passing Toolkit for Scientific Computations

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob F.; Saini, Subhash (Technical Monitor)

    1998-01-01

    The Charon toolkit for piecemeal development of high-efficiency parallel programs for scientific computing is described. The portable toolkit, callable from C and Fortran, provides flexible domain decompositions and high-level distributed constructs for easy translation of serial legacy code or design to distributed environments. Gradual tuning can subsequently be applied to obtain high performance, possibly by using explicit message passing. Charon also features general structured communications that support stencil-based computations with complex recurrences. Through the separation of partitioning and distribution, the toolkit can also be used for blocking of uni-processor code, and for debugging of parallel algorithms on serial machines. An elaborate review of recent parallelization aids is presented to highlight the need for a toolkit like Charon. Some performance results of parallelizing the NAS Parallel Benchmark SP program using Charon are given, showing good scalability.

  15. Charon Message-Passing Toolkit for Scientific Computations

    NASA Technical Reports Server (NTRS)

    VanderWijngarrt, Rob F.; Saini, Subhash (Technical Monitor)

    1998-01-01

    The Charon toolkit for piecemeal development of high-efficiency parallel programs for scientific computing is described. The portable toolkit, callable from C and Fortran, provides flexible domain decompositions and high-level distributed constructs for easy translation of serial legacy code or design to distributed environments. Gradual tuning can subsequently be applied to obtain high performance, possibly by using explicit message passing. Charon also features general structured communications that support stencil-based computations with complex recurrences. Through the separation of partitioning and distribution, the toolkit can also be used for blocking of uni-processor code, and for debugging of parallel algorithms on serial machines. An elaborate review of recent parallelization aids is presented to highlight the need for a toolkit like Charon. Some performance results of parallelizing the NAS Parallel Benchmark SP program using Charon are given, showing good scalability. Some performance results of parallelizing the NAS Parallel Benchmark SP program using Charon are given, showing good scalability.

  16. Approximate message passing with restricted Boltzmann machine priors

    NASA Astrophysics Data System (ADS)

    Tramel, Eric W.; Drémeau, Angélique; Krzakala, Florent

    2016-07-01

    Approximate message passing (AMP) has been shown to be an excellent statistical approach to signal inference and compressed sensing problems. The AMP framework provides modularity in the choice of signal prior; here we propose a hierarchical form of the Gauss–Bernoulli prior which utilizes a restricted Boltzmann machine (RBM) trained on the signal support to push reconstruction performance beyond that of simple i.i.d. priors for signals whose support can be well represented by a trained binary RBM. We present and analyze two methods of RBM factorization and demonstrate how these affect signal reconstruction performance within our proposed algorithm. Finally, using the MNIST handwritten digit dataset, we show experimentally that using an RBM allows AMP to approach oracle-support performance.

  17. Development of Message Passing Routines for High Performance Parallel Computations

    NASA Technical Reports Server (NTRS)

    Summers, Edward K.

    2004-01-01

    Computational Fluid Dynamics (CFD) calculations require a great deal of computing power for completing the detailed computations involved. In an effort shorten the time it takes to complete such calculations they are implemented on a parallel computer. In the case of a parallel computer some sort of message passing structure must be used to communicate between the computers because, unlike a single machine, each computer in a parallel computing cluster does not have access to all the data or run all the parts of the total program. Thus, message passing is used to divide up the data and send instructions to each machine. The nature of my work this summer involves programming the "message passing" aspect of the parallel computer. I am working on modifying an existing program, which was written with OpenMP, and does not use a multi-machine parallel computing structure, to work with Message Passing Interface (MPI) routines. The actual code is being written in the FORTRAN 90 programming language. My goal is to write a parameterized message passing structure that could be used for a variety of individual applications and implement it on Silicon Graphics Incorporated s (SGI) IRIX operating system. With this new parameterized structure engineers would be able to speed up computations for a wide variety of purposes without having to use larger and more expensive computing equipment from another division or another NASA center.

  18. MPF: A portable message passing facility for shared memory multiprocessors

    NASA Technical Reports Server (NTRS)

    Malony, Allen D.; Reed, Daniel A.; Mcguire, Patrick J.

    1987-01-01

    The design, implementation, and performance evaluation of a message passing facility (MPF) for shared memory multiprocessors are presented. The MPF is based on a message passing model conceptually similar to conversations. Participants (parallel processors) can enter or leave a conversation at any time. The message passing primitives for this model are implemented as a portable library of C function calls. The MPF is currently operational on a Sequent Balance 21000, and several parallel applications were developed and tested. Several simple benchmark programs are presented to establish interprocess communication performance for common patterns of interprocess communication. Finally, performance figures are presented for two parallel applications, linear systems solution, and iterative solution of partial differential equations.

  19. Standards for message-passing in a distributed memory environment

    SciTech Connect

    Walker, D.W.

    1992-08-01

    This report presents a summary of the main ideas presented at the First CRPC Work-shop on Standards for Message Passing in a Distributed Memory Environment, held April 29-30, 1992, in Williamsburg, Virginia. This workshop attracted 68 attendees including representative from major hardware and software vendors, and was the first in a series of workshops sponsored by the Center for Research on Parallel Computation. The aim of this series of workshops is to develop and implement a standard for message passing on distributed memory concurrent computers, thereby making it easier to develop efficient, portable application codes for such machines. The report discusses the main issues raised in the CRPC workshop, and describes proposed desirable features of a message passing standard for distributed memory environments.

  20. Efficiently passing messages in distributed spiking neural network simulation

    PubMed Central

    Thibeault, Corey M.; Minkovich, Kirill; O'Brien, Michael J.; Harris, Frederick C.; Srinivasa, Narayan

    2013-01-01

    Efficiently passing spiking messages in a neural model is an important aspect of high-performance simulation. As the scale of networks has increased so has the size of the computing systems required to simulate them. In addition, the information exchange of these resources has become more of an impediment to performance. In this paper we explore spike message passing using different mechanisms provided by the Message Passing Interface (MPI). A specific implementation, MVAPICH, designed for high-performance clusters with Infiniband hardware is employed. The focus is on providing information about these mechanisms for users of commodity high-performance spiking simulators. In addition, a novel hybrid method for spike exchange was implemented and benchmarked. PMID:23772213

  1. Containing Epidemic Outbreaks by Message-Passing Techniques

    NASA Astrophysics Data System (ADS)

    Altarelli, F.; Braunstein, A.; Dall'Asta, L.; Wakeling, J. R.; Zecchina, R.

    2014-04-01

    The problem of targeted network immunization can be defined as the one of finding a subset of nodes in a network to immunize or vaccinate in order to minimize a tradeoff between the cost of vaccination and the final (stationary) expected infection under a given epidemic model. Although computing the expected infection is a hard computational problem, simple and efficient mean-field approximations have been put forward in the literature in recent years. The optimization problem can be recast into a constrained one in which the constraints enforce local mean-field equations describing the average stationary state of the epidemic process. For a wide class of epidemic models, including the susceptible-infected-removed and the susceptible-infected-susceptible models, we define a message-passing approach to network immunization that allows us to study the statistical properties of epidemic outbreaks in the presence of immunized nodes as well as to find (nearly) optimal immunization sets for a given choice of parameters and costs. The algorithm scales linearly with the size of the graph, and it can be made efficient even on large networks. We compare its performance with topologically based heuristics, greedy methods, and simulated annealing on both random graphs and real-world networks.

  2. Mapping a battlefield simulation onto message-passing parallel architectures

    NASA Technical Reports Server (NTRS)

    Nicol, David M.

    1987-01-01

    Perhaps the most critical problem in distributed simulation is that of mapping: without an effective mapping of workload to processors the speedup potential of parallel processing cannot be realized. Mapping a simulation onto a message-passing architecture is especially difficult when the computational workload dynamically changes as a function of time and space; this is exactly the situation faced by battlefield simulations. This paper studies an approach where the simulated battlefield domain is first partitioned into many regions of equal size; typically there are more regions than processors. The regions are then assigned to processors; a processor is responsible for performing all simulation activity associated with the regions. The assignment algorithm is quite simple and attempts to balance load by exploiting locality of workload intensity. The performance of this technique is studied on a simple battlefield simulation implemented on the Flex/32 multiprocessor. Measurements show that the proposed method achieves reasonable processor efficiencies. Furthermore, the method shows promise for use in dynamic remapping of the simulation.

  3. Parallelized direct execution simulation of message-passing parallel programs

    NASA Technical Reports Server (NTRS)

    Dickens, Phillip M.; Heidelberger, Philip; Nicol, David M.

    1994-01-01

    As massively parallel computers proliferate, there is growing interest in findings ways by which performance of massively parallel codes can be efficiently predicted. This problem arises in diverse contexts such as parallelizing computers, parallel performance monitoring, and parallel algorithm development. In this paper we describe one solution where one directly executes the application code, but uses a discrete-event simulator to model details of the presumed parallel machine such as operating system and communication network behavior. Because this approach is computationally expensive, we are interested in its own parallelization specifically the parallelization of the discrete-event simulator. We describe methods suitable for parallelized direct execution simulation of message-passing parallel programs, and report on the performance of such a system, Large Application Parallel Simulation Environment (LAPSE), we have built on the Intel Paragon. On all codes measured to date, LAPSE predicts performance well typically within 10 percent relative error. Depending on the nature of the application code, we have observed low slowdowns (relative to natively executing code) and high relative speedups using up to 64 processors.

  4. Statistics of Epidemics in Networks by Passing Messages

    NASA Astrophysics Data System (ADS)

    Shrestha, Munik Kumar

    Epidemic processes are common out-of-equilibrium phenomena of broad interdisciplinary interest. In this thesis, we show how message-passing approach can be a helpful tool for simulating epidemic models in disordered medium like networks, and in particular for estimating the probability that a given node will become infectious at a particular time. The sort of dynamics we consider are stochastic, where randomness can arise from the stochastic events or from the randomness of network structures. As in belief propagation, variables or messages in message-passing approach are defined on the directed edges of a network. However, unlike belief propagation, where the posterior distributions are updated according to Bayes' rule, in message-passing approach we write differential equations for the messages over time. It takes correlations between neighboring nodes into account while preventing causal signals from backtracking to their immediate source, and thus avoids "echo chamber effects" where a pair of adjacent nodes each amplify the probability that the other is infectious. In our first results, we develop a message-passing approach to threshold models of behavior popular in sociology. These are models, first proposed by Granovetter, where individuals have to hear about a trend or behavior from some number of neighbors before adopting it themselves. In thermodynamic limit of large random networks, we provide an exact analytic scheme while calculating the time dependence of the probabilities and thus learning about the whole dynamics of bootstrap percolation, which is a simple model known in statistical physics for exhibiting discontinuous phase transition. As an application, we apply a similar model to financial networks, studying when bankruptcies spread due to the sudden devaluation of shared assets in overlapping portfolios. We predict that although diversification may be good for individual institutions, it can create dangerous systemic effects, and as a result

  5. Neighbourhood-consensus message passing and its potentials in image processing applications

    NASA Astrophysics Data System (ADS)

    Ružic, Tijana; Pižurica, Aleksandra; Philips, Wilfried

    2011-03-01

    In this paper, a novel algorithm for inference in Markov Random Fields (MRFs) is presented. Its goal is to find approximate maximum a posteriori estimates in a simple manner by combining neighbourhood influence of iterated conditional modes (ICM) and message passing of loopy belief propagation (LBP). We call the proposed method neighbourhood-consensus message passing because a single joint message is sent from the specified neighbourhood to the central node. The message, as a function of beliefs, represents the agreement of all nodes within the neighbourhood regarding the labels of the central node. This way we are able to overcome the disadvantages of reference algorithms, ICM and LBP. On one hand, more information is propagated in comparison with ICM, while on the other hand, the huge amount of pairwise interactions is avoided in comparison with LBP by working with neighbourhoods. The idea is related to the previously developed iterated conditional expectations algorithm. Here we revisit it and redefine it in a message passing framework in a more general form. The results on three different benchmarks demonstrate that the proposed technique can perform well both for binary and multi-label MRFs without any limitations on the model definition. Furthermore, it manifests improved performance over related techniques either in terms of quality and/or speed.

  6. GMH: A Message Passing Toolkit for GPU Clusters

    SciTech Connect

    Jie Chen, W. Watson, Weizhen Mao

    2011-01-01

    Driven by the market demand for high-definition 3D graphics, commodity graphics processing units (GPUs) have evolved into highly parallel, multi-threaded, many-core processors, which are ideal for data parallel computing. Many applications have been ported to run on a single GPU with tremendous speedups using general C-style programming languages such as CUDA. However, large applications require multiple GPUs and demand explicit message passing. This paper presents a message passing toolkit, called GMH (GPU Message Handler), on NVIDIA GPUs. This toolkit utilizes a data-parallel thread group as a way to map multiple GPUs on a single host to an MPI rank, and introduces a notion of virtual GPUs as a way to bind a thread to a GPU automatically. This toolkit provides high performance MPI style point-to-point and collective communication, but more importantly, facilitates event-driven APIs to allow an application to be managed and executed by the toolkit at runtime.

  7. Trace-Driven Debugging of Message Passing Programs

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Hood, Robert; Lopez, Louis; Bailey, David (Technical Monitor)

    1998-01-01

    In this paper we report on features added to a parallel debugger to simplify the debugging of parallel message passing programs. These features include replay, setting consistent breakpoints based on interprocess event causality, a parallel undo operation, and communication supervision. These features all use trace information collected during the execution of the program being debugged. We used a number of different instrumentation techniques to collect traces. We also implemented trace displays using two different trace visualization systems. The implementation was tested on an SGI Power Challenge cluster and a network of SGI workstations.

  8. Charon Message-Passing Toolkit for Scientific Computations

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob F.; Yan, Jerry (Technical Monitor)

    2000-01-01

    Charon is a library, callable from C and Fortran, that aids the conversion of structured-grid legacy codes-such as those used in the numerical computation of fluid flows-into parallel, high- performance codes. Key are functions that define distributed arrays, that map between distributed and non-distributed arrays, and that allow easy specification of common communications on structured grids. The library is based on the widely accepted MPI message passing standard. We present an overview of the functionality of Charon, and some representative results.

  9. n-body simulations using message passing parallel computers.

    NASA Astrophysics Data System (ADS)

    Grama, A. Y.; Kumar, V.; Sameh, A.

    The authors present new parallel formulations of the Barnes-Hut method for n-body simulations on message passing computers. These parallel formulations partition the domain efficiently incurring minimal communication overhead. This is in contrast to existing schemes that are based on sorting a large number of keys or on the use of global data structures. The new formulations are augmented by alternate communication strategies which serve to minimize communication overhead. The impact of these communication strategies is experimentally studied. The authors report on experimental results obtained from an astrophysical simulation on an nCUBE2 parallel computer.

  10. The Edge-Disjoint Path Problem on Random Graphs by Message-Passing

    PubMed Central

    2015-01-01

    We present a message-passing algorithm to solve a series of edge-disjoint path problems on graphs based on the zero-temperature cavity equations. Edge-disjoint paths problems are important in the general context of routing, that can be defined by incorporating under a unique framework both traffic optimization and total path length minimization. The computation of the cavity equations can be performed efficiently by exploiting a mapping of a generalized edge-disjoint path problem on a star graph onto a weighted maximum matching problem. We perform extensive numerical simulations on random graphs of various types to test the performance both in terms of path length minimization and maximization of the number of accommodated paths. In addition, we test the performance on benchmark instances on various graphs by comparison with state-of-the-art algorithms and results found in the literature. Our message-passing algorithm always outperforms the others in terms of the number of accommodated paths when considering non trivial instances (otherwise it gives the same trivial results). Remarkably, the largest improvement in performance with respect to the other methods employed is found in the case of benchmarks with meshes, where the validity hypothesis behind message-passing is expected to worsen. In these cases, even though the exact message-passing equations do not converge, by introducing a reinforcement parameter to force convergence towards a sub optimal solution, we were able to always outperform the other algorithms with a peak of 27% performance improvement in terms of accommodated paths. On random graphs, we numerically observe two separated regimes: one in which all paths can be accommodated and one in which this is not possible. We also investigate the behavior of both the number of paths to be accommodated and their minimum total length. PMID:26710102

  11. The Edge-Disjoint Path Problem on Random Graphs by Message-Passing.

    PubMed

    Altarelli, Fabrizio; Braunstein, Alfredo; Dall'Asta, Luca; De Bacco, Caterina; Franz, Silvio

    2015-01-01

    We present a message-passing algorithm to solve a series of edge-disjoint path problems on graphs based on the zero-temperature cavity equations. Edge-disjoint paths problems are important in the general context of routing, that can be defined by incorporating under a unique framework both traffic optimization and total path length minimization. The computation of the cavity equations can be performed efficiently by exploiting a mapping of a generalized edge-disjoint path problem on a star graph onto a weighted maximum matching problem. We perform extensive numerical simulations on random graphs of various types to test the performance both in terms of path length minimization and maximization of the number of accommodated paths. In addition, we test the performance on benchmark instances on various graphs by comparison with state-of-the-art algorithms and results found in the literature. Our message-passing algorithm always outperforms the others in terms of the number of accommodated paths when considering non trivial instances (otherwise it gives the same trivial results). Remarkably, the largest improvement in performance with respect to the other methods employed is found in the case of benchmarks with meshes, where the validity hypothesis behind message-passing is expected to worsen. In these cases, even though the exact message-passing equations do not converge, by introducing a reinforcement parameter to force convergence towards a sub optimal solution, we were able to always outperform the other algorithms with a peak of 27% performance improvement in terms of accommodated paths. On random graphs, we numerically observe two separated regimes: one in which all paths can be accommodated and one in which this is not possible. We also investigate the behavior of both the number of paths to be accommodated and their minimum total length. PMID:26710102

  12. A draft standard for message passing in a distributed memory environment

    SciTech Connect

    Dongarra, J.J. |; Hempel, R.; Hey, A.J.G.; Walker, D.W.

    1994-09-01

    This paper describes Message Passing Interface 1 (MPI1), a proposed library interface standard for supporting point-to-point message passing. The intended standard will be provided with Fortran 77 and C interfaces, and will form the basis of a standard high level communication environment featuring collective communication and data distribution transformations. The standard proposed here provides blocking and nonblocking message passing between pairs of processes, with message selectivity by source process and message type. Provision is made for noncontiguous messages. Context control provides a convenient means of avoiding message selectivity conflicts between different phases of an application. The ability to form and manipulate process groups permits task parallelism to be exploited.

  13. MPI-2: Extending the Message-Passing Interface

    SciTech Connect

    Geist, A.; Gropp, W.; Lusk, E.; Huss-Lederman, S. |; Lumsdaine, A.; Saphir, W.; Skjellum, T.; Snir, M.

    1996-10-01

    This paper describes current activities of the MPI-2 Forum. The MPI - 2 Forum is a group of parallel computer vendors, library writers, and application specialists working together to define a set of extensions to MPI (Message Passing Interface). MPI was defined by the same process and now has many implementations, both vendor- proprietary and publicly available, for a wide variety of parallel computing environments. In this paper we present the salient aspects of the evolving MPI-2 document as it now stands. We discuss proposed extensions and enhancements to MPI in the areas of dynamic process management, one-sided operations, collective operations, new language binding, real-time computing, external interfaces, and miscellaneous topics.

  14. Parallelization of a hydrological model using the message passing interface

    USGS Publications Warehouse

    Wu, Yiping; Li, Tiejian; Sun, Liqun; Chen, Ji

    2013-01-01

    With the increasing knowledge about the natural processes, hydrological models such as the Soil and Water Assessment Tool (SWAT) are becoming larger and more complex with increasing computation time. Additionally, other procedures such as model calibration, which may require thousands of model iterations, can increase running time and thus further reduce rapid modeling and analysis. Using the widely-applied SWAT as an example, this study demonstrates how to parallelize a serial hydrological model in a Windows® environment using a parallel programing technology—Message Passing Interface (MPI). With a case study, we derived the optimal values for the two parameters (the number of processes and the corresponding percentage of work to be distributed to the master process) of the parallel SWAT (P-SWAT) on an ordinary personal computer and a work station. Our study indicates that model execution time can be reduced by 42%–70% (or a speedup of 1.74–3.36) using multiple processes (two to five) with a proper task-distribution scheme (between the master and slave processes). Although the computation time cost becomes lower with an increasing number of processes (from two to five), this enhancement becomes less due to the accompanied increase in demand for message passing procedures between the master and all slave processes. Our case study demonstrates that the P-SWAT with a five-process run may reach the maximum speedup, and the performance can be quite stable (fairly independent of a project size). Overall, the P-SWAT can help reduce the computation time substantially for an individual model run, manual and automatic calibration procedures, and optimization of best management practices. In particular, the parallelization method we used and the scheme for deriving the optimal parameters in this study can be valuable and easily applied to other hydrological or environmental models.

  15. Message Passing vs. Shared Address Space on a Cluster of SMPs

    NASA Technical Reports Server (NTRS)

    Shan, Hongzhang; Singh, Jaswinder Pal; Oliker, Leonid; Biswas, Rupak

    2000-01-01

    The convergence of scalable computer architectures using clusters of PCs (or PC-SMPs) with commodity networking has become an attractive platform for high end scientific computing. Currently, message-passing and shared address space (SAS) are the two leading programming paradigms for these systems. Message-passing has been standardized with MPI, and is the most common and mature programming approach. However message-passing code development can be extremely difficult, especially for irregular structured computations. SAS offers substantial ease of programming, but may suffer from performance limitations due to poor spatial locality, and high protocol overhead. In this paper, we compare the performance of and programming effort, required for six applications under both programming models on a 32 CPU PC-SMP cluster. Our application suite consists of codes that typically do not exhibit high efficiency under shared memory programming. due to their high communication to computation ratios and complex communication patterns. Results indicate that SAS can achieve about half the parallel efficiency of MPI for most of our applications: however, on certain classes of problems SAS performance is competitive with MPI. We also present new algorithms for improving the PC cluster performance of MPI collective operations.

  16. Space Reclamation for Uncoordinated Checkpointing in Message-Passing Systems. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Wang, Yi-Min

    1993-01-01

    Checkpointing and rollback recovery are techniques that can provide efficient recovery from transient process failures. In a message-passing system, the rollback of a message sender may cause the rollback of the corresponding receiver, and the system needs to roll back to a consistent set of checkpoints called recovery line. If the processes are allowed to take uncoordinated checkpoints, the above rollback propagation may result in the domino effect which prevents recovery line progression. Traditionally, only obsolete checkpoints before the global recovery line can be discarded, and the necessary and sufficient condition for identifying all garbage checkpoints has remained an open problem. A necessary and sufficient condition for achieving optimal garbage collection is derived and it is proved that the number of useful checkpoints is bounded by N(N+1)/2, where N is the number of processes. The approach is based on the maximum-sized antichain model of consistent global checkpoints and the technique of recovery line transformation and decomposition. It is also shown that, for systems requiring message logging to record in-transit messages, the same approach can be used to achieve optimal message log reclamation. As a final topic, a unifying framework is described by considering checkpoint coordination and exploiting piecewise determinism as mechanisms for bounding rollback propagation, and the applicability of the optimal garbage collection algorithm to domino-free recovery protocols is demonstrated.

  17. Intel NX to PVM 3.2 message passing conversion library

    NASA Technical Reports Server (NTRS)

    Arthur, Trey; Nelson, Michael L.

    1993-01-01

    NASA Langley Research Center has developed a library that allows Intel NX message passing codes to be executed under the more popular and widely supported Parallel Virtual Machine (PVM) message passing library. PVM was developed at Oak Ridge National Labs and has become the defacto standard for message passing. This library will allow the many programs that were developed on the Intel iPSC/860 or Intel Paragon in a Single Program Multiple Data (SPMD) design to be ported to the numerous architectures that PVM (version 3.2) supports. Also, the library adds global operations capability to PVM. A familiarity with Intel NX and PVM message passing is assumed.

  18. A real-time MPEG software decoder using a portable message-passing library

    SciTech Connect

    Kwong, Man Kam; Tang, P.T. Peter; Lin, Biquan

    1995-12-31

    We present a real-time MPEG software decoder that uses message-passing libraries such as MPL, p4 and MPI. The parallel MPEG decoder currently runs on the IBM SP system but can be easil ported to other parallel machines. This paper discusses our parallel MPEG decoding algorithm as well as the parallel programming environment under which it uses. Several technical issues are discussed, including balancing of decoding speed, memory limitation, 1/0 capacities, and optimization of MPEG decoding components. This project shows that a real-time portable software MPEG decoder is feasible in a general-purpose parallel machine.

  19. A proposal for a user-level, message passing interface in a distributed memory environment

    SciTech Connect

    Dongarra, J.J. . Dept. of Computer Science Oak Ridge National Lab., TN ); Hempel, R. ); Hey, A.J.G. . Dept. of Electronics and Computer Science); Walker, D.W. )

    1993-02-01

    This paper describes Message Passing Interface 1 (MPI1), a proposed library interface standard for supporting point-to-point message passing. The intended standard will be provided with Fortran 77 and C interfaces, and will form the basis of a standard high level communication environment featuring collective communication and data distribution transformations. The standard proposed here provides blocking, nonblocking, and synchronized message passing between pairs of processes, with message selectivity by source process and message type. Provision is made for noncontiguous messages. Context control provides a convenient means of avoiding message selectivity conflicts between different phases of an application. The ability to form and manipulate process groups permits task parallelism to be exploited, and is a useful abstraction in controlling certain types of collective communication.

  20. Verification of Faulty Message Passing Systems with Continuous State Space in PVS

    NASA Technical Reports Server (NTRS)

    Pilotto, Concetta; White, Jerome

    2010-01-01

    We present a library of Prototype Verification System (PVS) meta-theories that verifies a class of distributed systems in which agent commu nication is through message-passing. The theoretic work, outlined in, consists of iterative schemes for solving systems of linear equations , such as message-passing extensions of the Gauss and Gauss-Seidel me thods. We briefly review that work and discuss the challenges in formally verifying it.

  1. Message passing for integrating and assessing renewable generation in a redundant power grid

    SciTech Connect

    Zdeborova, Lenka; Backhaus, Scott; Chertkov, Michael

    2009-01-01

    A simplified model of a redundant power grid is used to study integration of fluctuating renewable generation. The grid consists of large number of generator and consumer nodes. The net power consumption is determined by the difference between the gross consumption and the level of renewable generation. The gross consumption is drawn from a narrow distribution representing the predictability of aggregated loads, and we consider two different distributions representing wind and solar resources. Each generator is connected to D consumers, and redundancy is built in by connecting R {le} D of these consumers to other generators. The lines are switchable so that at any instance each consumer is connected to a single generator. We explore the capacity of the renewable generation by determining the level of 'firm' generation capacity that can be displaced for different levels of redundancy R. We also develop message-passing control algorithm for finding switch sellings where no generator is overloaded.

  2. Incremental Parallelization of Non-Data-Parallel Programs Using the Charon Message-Passing Library

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob F.

    2000-01-01

    , gather/scatter, and redistribution. At the end of the conversion process most intermediate Charon function calls will have been removed, the non-distributed arrays will have been deleted, and virtually the only remaining Charon functions calls are the high-level, highly optimized communications. Distribution of the data is under complete control of the programmer, although a wide range of useful distributions is easily available through predefined functions. A crucial aspect of the library is that it does not allocate space for distributed arrays, but accepts programmer-specified memory. This has two major consequences. First, codes parallelized using Charon do not suffer from encapsulation; user data is always directly accessible. This provides high efficiency, and also retains the possibility of using message passing directly for highly irregular communications. Second, non-distributed arrays can be interpreted as (trivial) distributions in the Charon sense, which allows them to be mapped to truly distributed arrays, and vice versa. This is the mechanism that enables incremental parallelization. In this paper we provide a brief introduction of the library and then focus on the actual steps in the parallelization process, using some representative examples from, among others, the NAS Parallel Benchmarks. We show how a complicated two-dimensional pipeline-the prototypical non-data-parallel algorithm- can be constructed with ease. To demonstrate the flexibility of the library, we give examples of the stepwise, efficient parallel implementation of nonlocal boundary conditions common in aircraft simulations, as well as the construction of the sequence of grids required for multigrid.

  3. A test implementation of the MPI draft message-passing standard

    SciTech Connect

    Gropp, W.; Lusk, E.

    1992-12-01

    Message passing is a common method for programming parallel computers. The lack of a standard has significantly impeded the development of portable software libraries for these machines. Recently, an ad-hoc committee was formed to develop a standard for message-passing software for parallel computers. This group first met in April 1992 at a workshop sponsored in part by the Center for Research on Parallel Computation (CRPC). Four of the attendees at that meeting produced a draft standard, henceforth referred to as the MPI (Message-Passing Interface) draft standard. After review by a larger group, and significant changes in the document, a meeting was held in November to discuss the MPI draft standard. This document is a result of those discussions; it describes a running implementation of in most of the proposed standard,plus additional routines that were suggested by the discussions at the November meeting.

  4. Optimizing spread dynamics on graphs by message passing

    NASA Astrophysics Data System (ADS)

    Altarelli, F.; Braunstein, A.; Dall'Asta, L.; Zecchina, R.

    2013-09-01

    Cascade processes are responsible for many important phenomena in natural and social sciences. Simple models of irreversible dynamics on graphs, in which nodes activate depending on the state of their neighbors, have been successfully applied to describe cascades in a large variety of contexts. Over the past decades, much effort has been devoted to understanding the typical behavior of the cascades arising from initial conditions extracted at random from some given ensemble. However, the problem of optimizing the trajectory of the system, i.e. of identifying appropriate initial conditions to maximize (or minimize) the final number of active nodes, is still considered to be practically intractable, with the only exception being models that satisfy a sort of diminishing returns property called submodularity. Submodular models can be approximately solved by means of greedy strategies, but by definition they lack cooperative characteristics which are fundamental in many real systems. Here we introduce an efficient algorithm based on statistical physics for the optimization of trajectories in cascade processes on graphs. We show that for a wide class of irreversible dynamics, even in the absence of submodularity, the spread optimization problem can be solved efficiently on large networks. Analytic and algorithmic results on random graphs are complemented by the solution of the spread maximization problem on a real-world network (the Epinions consumer reviews network).

  5. Scampi: a robust approximate message-passing framework for compressive imaging

    NASA Astrophysics Data System (ADS)

    Barbier, Jean; Tramel, Eric W.; Krzakala, Florent

    2016-03-01

    Reconstruction of images from noisy linear measurements is a core problem in image processing, for which convex optimization methods based on total variation (TV) minimization have been the long-standing state-of-the-art. We present an alternative probabilistic reconstruction procedure based on approximate message-passing, Scampi, which operates in the compressive regime, where the inverse imaging problem is underdetermined. While the proposed method is related to the recently proposed GrAMPA algorithm of Borgerding, Schniter, and Rangan, we further develop the probabilistic approach to compressive imaging by introducing an expectation-maximization learning of model parameters, making the Scampi robust to model uncertainties. Additionally, our numerical experiments indicate that Scampi can provide reconstruction performance superior to both GrAMPA as well as convex approaches to TV reconstruction. Finally, through exhaustive best-case experiments, we show that in many cases the maximal performance of both Scampi and convex TV can be quite close, even though the approaches are a prori distinct. The theoretical reasons for this correspondence remain an open question. Nevertheless, the proposed algorithm remains more practical, as it requires far less parameter tuning to perform optimally.

  6. Two-Dimensional Pattern-Coupled Sparse Bayesian Learning via Generalized Approximate Message Passing

    NASA Astrophysics Data System (ADS)

    Fang, Jun; Zhang, Lizao; Li, Hongbin

    2016-06-01

    We consider the problem of recovering two-dimensional (2-D) block-sparse signals with \\emph{unknown} cluster patterns. Two-dimensional block-sparse patterns arise naturally in many practical applications such as foreground detection and inverse synthetic aperture radar imaging. To exploit the block-sparse structure, we introduce a 2-D pattern-coupled hierarchical Gaussian prior model to characterize the statistical pattern dependencies among neighboring coefficients. Unlike the conventional hierarchical Gaussian prior model where each coefficient is associated independently with a unique hyperparameter, the pattern-coupled prior for each coefficient not only involves its own hyperparameter, but also its immediate neighboring hyperparameters. Thus the sparsity patterns of neighboring coefficients are related to each other and the hierarchical model has the potential to encourage 2-D structured-sparse solutions. An expectation-maximization (EM) strategy is employed to obtain the maximum a posterior (MAP) estimate of the hyperparameters, along with the posterior distribution of the sparse signal. In addition, the generalized approximate message passing (GAMP) algorithm is embedded into the EM framework to efficiently compute an approximation of the posterior distribution of hidden variables, which results in a significant reduction in computational complexity. Numerical results are provided to illustrate the effectiveness of the proposed algorithm.

  7. MPWide: a light-weight library for efficient message passing over wide area networks

    NASA Astrophysics Data System (ADS)

    Groen, D.; Rieder, S.; Portegies Zwart, S.

    2013-12-01

    We present MPWide, a light weight communication library which allows efficient message passing over a distributed network. MPWide has been designed to connect application running on distributed (super)computing resources, and to maximize the communication performance on wide area networks for those without administrative privileges. It can be used to provide message-passing between application, move files, and make very fast connections in client-server environments. MPWide has already been applied to enable distributed cosmological simulations across up to four supercomputers on two continents, and to couple two different bloodflow simulations to form a multiscale simulation.

  8. Development of a low-latency scalar communication routine on message-passing architectures

    SciTech Connect

    Pai, R.

    1994-01-11

    One of the most significant advances in computer systems over the past decade is parallel processing. To be scalable to a large number of processing nodes and to be able to support multiple levels and forms of parallelism and its flexible use, new parallel machines have to be multicomputer architectures that have general networking support and extremely low internode communication latencies. The performance of a program when ported to a parallel machine is limited mainly by the internode communication latencies of the machine. Therefore, the best parallel applications are those that seldom require communications which must be routed through the nodes. Thus the ratio of computation time to that of communication time is what determines, to a large extent, the performance metrics of an algorithm. The cost of synchronization and load imbalance appear secondary to that of the time required for internode communication and I/O, for communication intensive applications. This thesis is organized in chapters. The first chapter deals with the communication strategies in various message-passing computers. A taxonomy of inter-node communication strategies is presented in the second chapter and a comparison of the strategies in some existing machines is done. The implementation of communication in nCUBE Vertex O.S is explained in the third chapter. The fourth chapter deals with the communication routines in the Vertex O.S, and the last chapter explains the development and implementation of the scalar communication call. Finally some conclusions are presented.

  9. Precoder selection scheme based on message-passing approach: a practical perspective

    NASA Astrophysics Data System (ADS)

    Guerreiro, Igor M.; Cavalcante, Charles C.; Hui, Dennis

    2014-10-01

    This work addresses a distributed technique to precoding matrices coordination in a multi-cell network. We propose an iterative method based on a message-passing algorithm in factor graphs. Finite precoder codebooks for different MIMO setups are adopted for beam forming purposes. Conversely, practical cellular networks usually solve the precoder selection problem in a non-iterative manner based on the best response method. Nevertheless, this method may not provide a near-optimal solution. For more realistic results, the wireless channel is modeled based on measured data that comprises spatial correlation effects. Evaluations on the potential of such an approach are provided and its performance is compared with the selfish/greedy approach. The capability of reaching the globally optimal solution is evaluated, as well as its performance per iteration. Simulation results for the precoder selection example are presented and discussed, which show that the graph-based technique generally obtains gain in system capacity over both the non-iterative and selfish approaches. Besides, the proposed method usually reaches the global optima in an efficient manner in terms of signaling load.

  10. QMP-MVIA: a message passing system for Linux clusters with gigabit Ethernet mesh connections

    SciTech Connect

    Jie Chen; W. Watson III; Robert Edwards; Weizhen Mao

    2004-09-01

    Recent progress in performance coupled with a decline in price for copper-based gigabit Ethernet (GigE) interconnects makes them an attractive alternative to expensive high speed network interconnects (NIC) when constructing Linux clusters. However traditional message passing systems based on TCP for GigE interconnects cannot fully utilize the raw performance of today's GigE interconnects due to the overhead of kernel involvement and multiple memory copies during sending and receiving messages. The overhead is more evident in the case of mesh connected Linux clusters using multiple GigE interconnects in a single host. We present a general message passing system called QMP-MVIA (QCD Message Passing over M-VIA) for Linux clusters with mesh connections using GigE interconnects. In particular, we evaluate and compare the performance characteristics of TCP and M-VIA (an implementation of the VIA specification) software for a mesh communication architecture to demonstrate the feasibility of using M-VIA as a point-to-point communication software, on which QMP-MVIA is based. Furthermore, we illustrate the design and implementation of QMP-MVIA for mesh connected Linux clusters with emphasis on both point-to-point and collective communications, and demonstrate that QMP-MVIA message passing system using GigE interconnects achieves bandwidth and latency that are not only better than systems based on TCP but also compare favorably to systems using some of the specialized high speed interconnects in a switched architecture at much lower cost.

  11. Message-passing approach for recurrent-state epidemic models on networks

    NASA Astrophysics Data System (ADS)

    Shrestha, Munik; Scarpino, Samuel V.; Moore, Cristopher

    2015-08-01

    Epidemic processes are common out-of-equilibrium phenomena of broad interdisciplinary interest. Recently, dynamic message-passing (DMP) has been proposed as an efficient algorithm for simulating epidemic models on networks, and in particular for estimating the probability that a given node will become infectious at a particular time. To date, DMP has been applied exclusively to models with one-way state changes, as opposed to models like SIS and SIRS where nodes can return to previously inhabited states. Because many real-world epidemics can exhibit such recurrent dynamics, we propose a DMP algorithm for complex, recurrent epidemic models on networks. Our approach takes correlations between neighboring nodes into account while preventing causal signals from backtracking to their immediate source, and thus avoids "echo chamber effects" where a pair of adjacent nodes each amplify the probability that the other is infectious. We demonstrate that this approach well approximates results obtained from Monte Carlo simulation and that its accuracy is often superior to the pair approximation (which also takes second-order correlations into account). Moreover, our approach is more computationally efficient than the pair approximation, especially for complex epidemic models: the number of variables in our DMP approach grows as 2 m k where m is the number of edges and k is the number of states, as opposed to m k2 for the pair approximation. We suspect that the resulting reduction in computational effort, as well as the conceptual simplicity of DMP, will make it a useful tool in epidemic modeling, especially for high-dimensional inference tasks.

  12. A high-performance, portable implementation of the MPI message passing interface standard.

    SciTech Connect

    Gropp, W.; Lusk, E.; Doss, N.; Skjellum, A.; Mathematics and Computer Science; Mississippi State Univ.

    1996-09-01

    MPI (Message Passing Interface) is a specification for a standard library for message passing that was defined by the MPI Forum, a broadly based group of parallel computer vendors, library writers, and applications specialists. Multiple implementations of MPI have been developed. In this paper, we describe MPICH, unique among existing implementations in its design goal of combining portability with high performance. We document its portability and performance and describe the architecture by which these features are simultaneously achieved. We also discuss the set of tools that accompany the free distribution of MPICH, which constitute the beginnings of a portable parallel programming environment. A project of this scope inevitably imparts lessons about parallel computing, the specification being followed, the current hardware and software environment for parallel computing, and project management; we describe those we have learned. Finally, we discuss future developments for MPICH, including those necessary to accommodate extensions to the MPI Standard now being contemplated by the MPI Forum.

  13. The design of a standard message passing interface for distributed memory concurrent computers

    SciTech Connect

    Walker, D.W.

    1993-10-01

    This paper presents an overview of MPI, a proposed standard message passing interface for MIMD distributed memory concurrent computers. The design of MPI has been a collective effort involving researchers in the United States and Europe from many organizations and institutions. MPI includes point-to-point and collective communication routines, as well as support for process groups, communication contexts, and application topologies. While making use of new ideas where appropriate, the MPI standard is based largely on current practice.

  14. The Portals 3.0 Message Passing Interface Revision 1.0

    SciTech Connect

    BRIGHTWELL,RONALD B.; HUDSON,TRAMMELL B.; RIESEN,ROLF E.; MACCABE,ARTHUR B.

    1999-12-01

    This report presents a specification for the Portals 3.0 message passing interface. Portals 3.0 is intended to allow scalable, high-performance network communication between nodes of a parallel computing system. Specifically, it is designed to support a parallel computing platform composed of clusters of commodity workstations connected by a commodity system area network fabric. In addition, Portals 3.0 is well suited to massively parallel processing and embedded systems. Portals 3.0 represents an adoption of the data movement layer developed for massively parallel processing platforms, such as the 4500-node Intel TeraFLOPS machine.

  15. Formal verification of an oral messages algorithm for interactive consistency

    NASA Technical Reports Server (NTRS)

    Rushby, John

    1992-01-01

    The formal specification and verification of an algorithm for Interactive Consistency based on the Oral Messages algorithm for Byzantine Agreement is described. We compare our treatment with that of Bevier and Young, who presented a formal specification and verification for a very similar algorithm. Unlike Bevier and Young, who observed that 'the invariant maintained in the recursive subcases of the algorithm is significantly more complicated than is suggested by the published proof' and who found its formal verification 'a fairly difficult exercise in mechanical theorem proving,' our treatment is very close to the previously published analysis of the algorithm, and our formal specification and verification are straightforward. This example illustrates how delicate choices in the formulation of the problem can have significant impact on the readability of its formal specification and on the tractability of its formal verification.

  16. Multi-partitioning for ADI-schemes on message passing architectures

    NASA Technical Reports Server (NTRS)

    Vanderwijngaart, Rob F.

    1994-01-01

    A kind of discrete-operator splitting called Alternating Direction Implicit (ADI) has been found to be useful in simulating fluid flow problems. In particular, it is being used to study the effects of hot exhaust jets from high performance aircraft on landing surfaces. Decomposition techniques that minimize load imbalance and message-passing frequency are described. Three strategies that are investigated for implementing the NAS Scalar Penta-diagonal Parallel Benchmark (SP) are transposition, pipelined Gaussian elimination, and multipartitioning. The multipartitioning strategy, which was used on Ethernet, was found to be the most efficient, although it was considered only a moderate success because of Ethernet's limited communication properties. The efficiency derived largely from the coarse granularity of the strategy, which reduced latencies and allowed overlap of communication and computation.

  17. Comparative Study of Message Passing and Shared Memory Parallel Programming Models in Neural Network Training

    SciTech Connect

    Vitela, J.; Gordillo, J.; Cortina, L; Hanebutte, U.

    1999-12-14

    It is presented a comparative performance study of a coarse grained parallel neural network training code, implemented in both OpenMP and MPI, standards for shared memory and message passing parallel programming environments, respectively. In addition, these versions of the parallel training code are compared to an implementation utilizing SHMEM the native SGI/CRAY environment for shared memory programming. The multiprocessor platform used is a SGI/Cray Origin 2000 with up to 32 processors. It is shown that in this study, the native CRAY environment outperforms MPI for the entire range of processors used, while OpenMP shows better performance than the other two environments when using more than 19 processors. In this study, the efficiency is always greater than 60% regardless of the parallel programming environment used as well as of the number of processors.

  18. Parallel Brownian dynamics simulations with the message-passing and PGAS programming models

    NASA Astrophysics Data System (ADS)

    Teijeiro, C.; Sutmann, G.; Taboada, G. L.; Touriño, J.

    2013-04-01

    The simulation of particle dynamics is among the most important mechanisms to study the behavior of molecules in a medium under specific conditions of temperature and density. Several models can be used to compute efficiently the forces that act on each particle, and also the interactions between them. This work presents the design and implementation of a parallel simulation code for the Brownian motion of particles in a fluid. Two different parallelization approaches have been followed: (1) using traditional distributed memory message-passing programming with MPI, and (2) using the Partitioned Global Address Space (PGAS) programming model, oriented towards hybrid shared/distributed memory systems, with the Unified Parallel C (UPC) language. Different techniques for domain decomposition and work distribution are analyzed in terms of efficiency and programmability, in order to select the most suitable strategy. Performance results on a supercomputer using up to 2048 cores are also presented for both MPI and UPC codes.

  19. Comparison of cone beam artifacts reduction: two pass algorithm vs TV-based CS algorithm

    NASA Astrophysics Data System (ADS)

    Choi, Shinkook; Baek, Jongduk

    2015-03-01

    In a cone beam computed tomography (CBCT), the severity of the cone beam artifacts is increased as the cone angle increases. To reduce the cone beam artifacts, several modified FDK algorithms and compressed sensing based iterative algorithms have been proposed. In this paper, we used two pass algorithm and Gradient-Projection-Barzilai-Borwein (GPBB) algorithm to reduce the cone beam artifacts, and compared their performance using structural similarity (SSIM) index. In two pass algorithm, it is assumed that the cone beam artifacts are mainly caused by extreme-density(ED) objects, and therefore the algorithm reproduces the cone beam artifacts(i.e., error image) produced by ED objects, and then subtract it from the original image. GPBB algorithm is a compressed sensing based iterative algorithm which minimizes an energy function for calculating the gradient projection with the step size determined by the Barzilai- Borwein formulation, therefore it can estimate missing data caused by the cone beam artifacts. To evaluate the performance of two algorithms, we used testing objects consisting of 7 ellipsoids separated along the z direction and cone beam artifacts were generated using 30 degree cone angle. Even though the FDK algorithm produced severe cone beam artifacts with a large cone angle, two pass algorithm reduced the cone beam artifacts with small residual errors caused by inaccuracy of ED objects. In contrast, GPBB algorithm completely removed the cone beam artifacts and restored the original shape of the objects.

  20. Message passing vs. shared address space on a cluster of SMPs

    SciTech Connect

    Shan, Hongzhang; Singh, Jaswinder Pal; Oliker, Leonid; Biswas, Rupak

    2001-01-22

    The emergence of scalable computer architectures using clusters of PCs or PC-SMPs with commodity networking has made them attractive platforms for high-end scientific computing. Currently, message passing (MP) and shared address space (SAS) are the two leading programming paradigms for these systems. MP has been standardized with MPI, and is the most common and mature parallel programming approach. However, MP code development can be extremely difficult, especially for irregularly structured computations. SAS offers substantial ease of programming, but may suffer from performance limitations due to poor spatial locality and high protocol overhead. In this paper, they compare the performance of and programming effort required for six applications under both programming models on a 32-CPU PC-SMP cluster. Our application suite consists of codes that typically do not exhibit scalable performance under shared-memory programming due to their high communication-to-computation ratios and complex communication patterns. Results indicate that SAS can achieve about half the parallel efficiency of MPI for most of the applications; however, on certain classes of problems, SAS performance is competitive with MPI.

  1. Message Passing and Shared Address Space Parallelism on an SMP Cluster

    NASA Technical Reports Server (NTRS)

    Shan, Hongzhang; Singh, Jaswinder P.; Oliker, Leonid; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2002-01-01

    Currently, message passing (MP) and shared address space (SAS) are the two leading parallel programming paradigms. MP has been standardized with MPI, and is the more common and mature approach; however, code development can be extremely difficult, especially for irregularly structured computations. SAS offers substantial ease of programming, but may suffer from performance limitations due to poor spatial locality and high protocol overhead. In this paper, we compare the performance of and the programming effort required for six applications under both programming models on a 32-processor PC-SMP cluster, a platform that is becoming increasingly attractive for high-end scientific computing. Our application suite consists of codes that typically do not exhibit scalable performance under shared-memory programming due to their high communication-to-computation ratios and/or complex communication patterns. Results indicate that SAS can achieve about half the parallel efficiency of MPI for most of our applications, while being competitive for the others. A hybrid MPI+SAS strategy shows only a small performance advantage over pure MPI in some cases. Finally, improved implementations of two MPI collective operations on PC-SMP clusters are presented.

  2. Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method

    PubMed Central

    Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

    2015-01-01

    Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting. PMID:26236773

  3. Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method.

    PubMed

    Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

    2015-01-01

    Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting. PMID:26236773

  4. Monitoring Data-Structure Evolution in Distributed Message-Passing Programs

    NASA Technical Reports Server (NTRS)

    Sarukkai, Sekhar R.; Beers, Andrew; Woodrow, Thomas S. (Technical Monitor)

    1996-01-01

    Monitoring the evolution of data structures in parallel and distributed programs, is critical for debugging its semantics and performance. However, the current state-of-art in tracking and presenting data-structure information on parallel and distributed environments is cumbersome and does not scale. In this paper we present a methodology that automatically tracks memory bindings (not the actual contents) of static and dynamic data-structures of message-passing C programs, using PVM. With the help of a number of examples we show that in addition to determining the impact of memory allocation overheads on program performance, graphical views can help in debugging the semantics of program execution. Scalable animations of virtual address bindings of source-level data-structures are used for debugging the semantics of parallel programs across all processors. In conjunction with light-weight core-files, this technique can be used to complement traditional debuggers on single processors. Detailed information (such as data-structure contents), on specific nodes, can be determined using traditional debuggers after the data structure evolution leading to the semantic error is observed graphically.

  5. Supporting the Development of Soft-Error Resilient Message Passing Applications using Simulation

    SciTech Connect

    Engelmann, Christian; Naughton III, Thomas J

    2016-01-01

    Radiation-induced bit flip faults are of particular concern in extreme-scale high-performance computing systems. This paper presents a simulation-based tool that enables the development of soft-error resilient message passing applications by permitting the investigation of their correctness and performance under various fault conditions. The documented extensions to the Extreme-scale Simulator (xSim) enable the injection of bit flip faults at specific of injection location(s) and fault activation time(s), while supporting a significant degree of configurability of the fault type. Experiments show that the simulation overhead with the new feature is ~2,325% for serial execution and ~1,730% at 128 MPI processes, both with very fine-grain fault injection. Fault injection experiments demonstrate the usefulness of the new feature by injecting bit flips in the input and output matrices of a matrix-matrix multiply application, revealing vulnerability of data structures, masking and error propagation. xSim is the very first simulation-based MPI performance tool that supports both, the injection of process failures and bit flip faults.

  6. Implementation of a Message Passing Interface into a Cloud-Resolving Model for Massively Parallel Computing

    NASA Technical Reports Server (NTRS)

    Juang, Hann-Ming Henry; Tao, Wei-Kuo; Zeng, Xi-Ping; Shie, Chung-Lin; Simpson, Joanne; Lang, Steve

    2004-01-01

    The capability for massively parallel programming (MPP) using a message passing interface (MPI) has been implemented into a three-dimensional version of the Goddard Cumulus Ensemble (GCE) model. The design for the MPP with MPI uses the concept of maintaining similar code structure between the whole domain as well as the portions after decomposition. Hence the model follows the same integration for single and multiple tasks (CPUs). Also, it provides for minimal changes to the original code, so it is easily modified and/or managed by the model developers and users who have little knowledge of MPP. The entire model domain could be sliced into one- or two-dimensional decomposition with a halo regime, which is overlaid on partial domains. The halo regime requires that no data be fetched across tasks during the computational stage, but it must be updated before the next computational stage through data exchange via MPI. For reproducible purposes, transposing data among tasks is required for spectral transform (Fast Fourier Transform, FFT), which is used in the anelastic version of the model for solving the pressure equation. The performance of the MPI-implemented codes (i.e., the compressible and anelastic versions) was tested on three different computing platforms. The major results are: 1) both versions have speedups of about 99% up to 256 tasks but not for 512 tasks; 2) the anelastic version has better speedup and efficiency because it requires more computations than that of the compressible version; 3) equal or approximately-equal numbers of slices between the x- and y- directions provide the fastest integration due to fewer data exchanges; and 4) one-dimensional slices in the x-direction result in the slowest integration due to the need for more memory relocation for computation.

  7. Efficient Tracing for On-the-Fly Space-Time Displays in a Debugger for Message Passing Programs

    NASA Technical Reports Server (NTRS)

    Hood, Robert; Matthews, Gregory

    2001-01-01

    In this work we describe the implementation of a practical mechanism for collecting and displaying trace information in a debugger for message passing programs. We introduce a trace format that is highly compressible while still providing information adequate for debugging purposes. We make the mechanism convenient for users to access by incorporating the trace collection in a set of wrappers for the MPI (message passing interface) communication library. We implement several debugger operations that use the trace display: consistent stoplines, undo, and rollback. They all are implemented using controlled replay, which executes at full speed in target processes until the appropriate position in the computation is reached. They provide convenient mechanisms for getting to places in the execution where the full power of a state-based debugger can be brought to bear on isolating communication errors.

  8. What it Takes to Get Passed On: Message Content, Style, and Structure as Predictors of Retransmission in the Boston Marathon Bombing Response

    PubMed Central

    Sutton, Jeannette; Gibson, C. Ben; Spiro, Emma S.; League, Cedar; Fitzhugh, Sean M.; Butts, Carter T.

    2015-01-01

    Message retransmission is a central aspect of information diffusion. In a disaster context, the passing on of official warning messages by members of the public also serves as a behavioral indicator of message salience, suggesting that particular messages are (or are not) perceived by the public to be both noteworthy and valuable enough to share with others. This study provides the first examination of terse message retransmission of official warning messages in response to a domestic terrorist attack, the Boston Marathon Bombing in 2013. Using messages posted from public officials’ Twitter accounts that were active during the period of the Boston Marathon bombing and manhunt, we examine the features of messages that are associated with their retransmission. We focus on message content, style, and structure, as well as the networked relationships of message senders to answer the question: what characteristics of a terse message sent under conditions of imminent threat predict its retransmission among members of the public? We employ a negative binomial model to examine how message characteristics affect message retransmission. We find that, rather than any single effect dominating the process, retransmission of official Tweets during the Boston bombing response was jointly influenced by various message content, style, and sender characteristics. These findings suggest the need for more work that investigates impact of multiple factors on the allocation of attention and on message retransmission during hazard events. PMID:26295584

  9. What it Takes to Get Passed On: Message Content, Style, and Structure as Predictors of Retransmission in the Boston Marathon Bombing Response.

    PubMed

    Sutton, Jeannette; Gibson, C Ben; Spiro, Emma S; League, Cedar; Fitzhugh, Sean M; Butts, Carter T

    2015-01-01

    Message retransmission is a central aspect of information diffusion. In a disaster context, the passing on of official warning messages by members of the public also serves as a behavioral indicator of message salience, suggesting that particular messages are (or are not) perceived by the public to be both noteworthy and valuable enough to share with others. This study provides the first examination of terse message retransmission of official warning messages in response to a domestic terrorist attack, the Boston Marathon Bombing in 2013. Using messages posted from public officials' Twitter accounts that were active during the period of the Boston Marathon bombing and manhunt, we examine the features of messages that are associated with their retransmission. We focus on message content, style, and structure, as well as the networked relationships of message senders to answer the question: what characteristics of a terse message sent under conditions of imminent threat predict its retransmission among members of the public? We employ a negative binomial model to examine how message characteristics affect message retransmission. We find that, rather than any single effect dominating the process, retransmission of official Tweets during the Boston bombing response was jointly influenced by various message content, style, and sender characteristics. These findings suggest the need for more work that investigates impact of multiple factors on the allocation of attention and on message retransmission during hazard events. PMID:26295584

  10. The development and performance of a message-passing version of the PAGOSA shock-wave physics code

    SciTech Connect

    Gardner, D.R.; Vaughan, C.T.

    1997-10-01

    A message-passing version of the PAGOSA shock-wave physics code has been developed at Sandia National Laboratories for multiple-instruction, multiple-data stream (MIMD) computers. PAGOSA is an explicit, Eulerian code for modeling the three-dimensional, high-speed hydrodynamic flow of fluids and the dynamic deformation of solids under high rates of strain. It was originally developed at Los Alamos National Laboratory for the single-instruction, multiple-data (SIMD) Connection Machine parallel computers. The performance of Sandia`s message-passing version of PAGOSA has been measured on two MIMD machines, the nCUBE 2 and the Intel Paragon XP/S. No special efforts were made to optimize the code for either machine. The measured scaled speedup (computational time for a single computational node divided by the computational time per node for fixed computational load) and grind time (computational time per cell per time step) show that the MIMD PAGOSA code scales linearly with the number of computational nodes used on a variety of problems, including the simulation of shaped-charge jets perforating an oil well casing. Scaled parallel efficiencies for MIMD PAGOSA are greater than 0.70 when the available memory per node is filled (or nearly filled) on hundreds to a thousand or more computational nodes on these two machines, indicating that the code scales very well. Thus good parallel performance can be achieved for complex and realistic applications when they are first implemented on MIMD parallel computers.

  11. Scalable High Performance Message Passing over InfiniBand for Open MPI

    SciTech Connect

    Friedley, A; Hoefler, T; Leininger, M L; Lumsdaine, A

    2007-10-24

    InfiniBand (IB) is a popular network technology for modern high-performance computing systems. MPI implementations traditionally support IB using a reliable, connection-oriented (RC) transport. However, per-process resource usage that grows linearly with the number of processes, makes this approach prohibitive for large-scale systems. IB provides an alternative in the form of a connectionless unreliable datagram transport (UD), which allows for near-constant resource usage and initialization overhead as the process count increases. This paper describes a UD-based implementation for IB in Open MPI as a scalable alternative to existing RC-based schemes. We use the software reliability capabilities of Open MPI to provide the guaranteed delivery semantics required by MPI. Results show that UD not only requires fewer resources at scale, but also allows for shorter MPI startup times. A connectionless model also improves performance for applications that tend to send small messages to many different processes.

  12. MPI on the I-WAY: a wide-area, multimethod implementation of the message passing interface

    SciTech Connect

    Foster, I.; Geisler, J.; Tuecke, S.

    1996-12-31

    High-speed wide-area networks enable innovative applications that integrate geographically distributed computing, database, graphics, and networking resources. The Message Passing Interface (MPI) can be used as a portable, high-performance programming model for such systems. However, the wide-area environment introduces challenging problems for the MPI implementor, because of the heterogeneity of both the underlying physical infrastructure and the authentication and software environment at different sites. In this article, we describe an MPI implementation that incorporates solutions to these problems. This implementation, which was developed for the I-WAY distributed-computing experiment, was constructed by layering MPICH on the Nexus multithreaded runtime system. Nexus provides automatic configuration mechanisms that can be used to select and configure authentication, process creation, and communication mechanisms in heterogeneous systems.

  13. Approximate message-passing with spatially coupled structured operators, with applications to compressed sensing and sparse superposition codes

    NASA Astrophysics Data System (ADS)

    Barbier, Jean; Schülke, Christophe; Krzakala, Florent

    2015-05-01

    We study the behavior of approximate message-passing (AMP), a solver for linear sparse estimation problems such as compressed sensing, when the i.i.d matrices—for which it has been specifically designed—are replaced by structured operators, such as Fourier and Hadamard ones. We show empirically that after proper randomization, the structure of the operators does not significantly affect the performances of the solver. Furthermore, for some specially designed spatially coupled operators, this allows a computationally fast and memory efficient reconstruction in compressed sensing up to the information-theoretical limit. We also show how this approach can be applied to sparse superposition codes, allowing the AMP decoder to perform at large rates for moderate block length.

  14. Baseline Estimation Algorithm with Block Adjustment for Multi-Pass Dual-Antenna Insar

    NASA Astrophysics Data System (ADS)

    Jin, Guowang; Xiong, Xin; Xu, Qing; Gong, Zhihui; Zhou, Yang

    2016-06-01

    Baseline parameters and interferometric phase offset need to be estimated accurately, for they are key parameters in processing of InSAR (Interferometric Synthetic Aperture Radar). If adopting baseline estimation algorithm with single pass, it needs large quantities of ground control points to estimate interferometric parameters for mosaicking multiple passes dual-antenna airborne InSAR data that covers large areas. What's more, there will be great difference between heights derived from different passes due to the errors of estimated parameters. So, an estimation algorithm of interferometric parameters with block adjustment for multi-pass dual-antenna InSAR is presented to reduce the needed ground control points and height's difference between different passes. The baseline estimation experiments were done with multi-pass InSAR data obtained by Chinese dual-antenna airborne InSAR system. Although there were less ground control points, the satisfied results were obtained, as validated the proposed baseline estimation algorithm.

  15. The Effect of Interrupts on Software Pipeline Execution on Message-Passing Architectures

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob F.; Sarukkai, Sekhar R.; Mehra, Pankaj; Craw, James M. (Technical Monitor)

    1995-01-01

    Pipelining is a common strategy for extracting parallelism from a collection of independent computational tasks, each of which is spread among a number of processors and has an implied data dependence. When implemented on MIMD parallel computers with finite process interrupt times, pipeline algorithms suffer from slowdown--in addition to the expected pipeline fill time--due to a wave-like propagation of delays. This phenomenon, which has been observed experimentally using the performance monitoring system AIMS, is investigated analytically, and an optimal correction is derived to eliminate the wave. Efficiency increase through the correction is verified experimentally.

  16. On the adequacy of message-passing parallel supercomputers for solving neutron transport problems

    SciTech Connect

    Azmy, Y.Y.

    1990-01-01

    A coarse-grained, static-scheduling parallelization of the standard iterative scheme used for solving the discrete-ordinates approximation of the neutron transport equation is described. The parallel algorithm is based on a decomposition of the angular domain along the discrete ordinates, thus naturally producing a set of completely uncoupled systems of equations in each iteration. Implementation of the parallel code on Intcl's iPSC/2 hypercube, and solutions to test problems are presented as evidence of the high speedup and efficiency of the parallel code. The performance of the parallel code on the iPSC/2 is analyzed, and a model for the CPU time as a function of the problem size (order of angular quadrature) and the number of participating processors is developed and validated against measured CPU times. The performance model is used to speculate on the potential of massively parallel computers for significantly speeding up real-life transport calculations at acceptable efficiencies. We conclude that parallel computers with a few hundred processors are capable of producing large speedups at very high efficiencies in very large three-dimensional problems. 10 refs., 8 figs.

  17. Task-parallel message passing interface implementation of Autodock4 for docking of very large databases of compounds using high-performance super-computers.

    PubMed

    Collignon, Barbara; Schulz, Roland; Smith, Jeremy C; Baudry, Jerome

    2011-04-30

    A message passing interface (MPI)-based implementation (Autodock4.lga.MPI) of the grid-based docking program Autodock4 has been developed to allow simultaneous and independent docking of multiple compounds on up to thousands of central processing units (CPUs) using the Lamarkian genetic algorithm. The MPI version reads a single binary file containing precalculated grids that represent the protein-ligand interactions, i.e., van der Waals, electrostatic, and desolvation potentials, and needs only two input parameter files for the entire docking run. In comparison, the serial version of Autodock4 reads ASCII grid files and requires one parameter file per compound. The modifications performed result in significantly reduced input/output activity compared with the serial version. Autodock4.lga.MPI scales up to 8192 CPUs with a maximal overhead of 16.3%, of which two thirds is due to input/output operations and one third originates from MPI operations. The optimal docking strategy, which minimizes docking CPU time without lowering the quality of the database enrichments, comprises the docking of ligands preordered from the most to the least flexible and the assignment of the number of energy evaluations as a function of the number of rotatable bounds. In 24 h, on 8192 high-performance computing CPUs, the present MPI version would allow docking to a rigid protein of about 300K small flexible compounds or 11 million rigid compounds. PMID:21387347

  18. QLWFPC2: Parallel-Processing Quick-Look WFPC2 Stellar Photometry Based on the Message Passing Interface

    NASA Astrophysics Data System (ADS)

    Mighell, K. J.

    2004-07-01

    I describe a new parallel-processing stellar photometry code called QLWFPC2 (http://www.noao.edu/staff/mighell/qlwfpc2) which is designed to do quick-look analysis of two entire WFPC2 observations from the Hubble Space Telescope in under 5 seconds using a fast Beowulf cluster with a Gigabit-Ethernet local network. This program is written in ANSI C and uses MPICH implementation of the Message Passing Interface from the Argonne National Laboratory for the parallel-processing communications, the CFITSIO library (from HEASARC at NASA's GSFC) for reading the standard FITS files from the HST Data Archive, and the Parameter Interface Library (from the INTEGRAL Science Data Center) for the IRAF parameter-file user interface. QLWFPC2 running on 4 processors takes about 2.4 seconds to analyze the WFPC2 archive datasets u37ga407r.c0.fits (F555W; 300 s) and u37ga401r.c0.fits (F814W; 300 s) of M54 (NGC 6715) which is the bright massive globular cluster near the center of the nearby Sagittarius dwarf spheroidal galaxy. The analysis of these HST observations of M54 lead to the serendipitous discovery of more than 50 new bright variable stars in the central region of M54. Most of the candidate variables stars are found on the PC1 images of the cluster center --- a region where no variables have been reported by previous ground-based studies of variables in M54. This discovery is an example of how QLWFPC2 can be used to quickly explore the time domain of observations in the HST Data Archive.

  19. QLWFPC2: Parallel-Processing Quick-Look WFPC2 Stellar Photometry based on the Message Passing Interface

    NASA Astrophysics Data System (ADS)

    Mighell, K. J.

    2003-12-01

    I describe a new parallel-processing stellar photometry code called QLWFPC2 which is designed to do quick-look analysis of two entire WFPC2 observations from the Hubble Space Telescope in under 5 seconds using a fast Beowulf cluster with a Gigabit Ethernet local network. This program is written in ANSI/ISO C and uses the MPICH implementation of the Message Passing Interface from the Argonne National Laboratory for the parallel-processing communications, the CFITSIO library (from HEASARC at NASA's GSFC) for reading the standard FITS files from the HST Data Archive and the Parameter Interface Library (from the INTEGRAL Science Data Center) for the IRAF parameter-file user interface. QLWFPC2 running on 4 processors takes about 2.4 seconds to analyze WFPC2 archive datasets u37ga407r.c0.fits (F555W; 300 s) and u37ga401r.c0.fits (F814W; 300 s) of M54 (NGC 6715) which is the bright massive globular cluster near the center of the nearby Sagittarius dwarf spheroidal galaxy. The analysis of these HST observations of M54 lead to the serendipitous discovery of more than 50 new bright variable stars in the central region of M54. Most of the candidate variables stars are found on the PC1 images of the cluster center --- a region where no variables have been reported by previous ground-based studies of variables in M54. This discovery is an example of how QLWFPC2 can be used to quickly explore the time domain of observations in the HST Data Archive. This work is supported by a grant from the National Aeronautics and Space Administration (NASA), Order No. S-13811-G, which was awarded by the Applied Information Systems Research Program (AISRP) of NASA's Office of Space Science (NRA 01-OSS-01).

  20. A scalable and practical one-pass clustering algorithm for recommender system

    NASA Astrophysics Data System (ADS)

    Khalid, Asra; Ghazanfar, Mustansar Ali; Azam, Awais; Alahmari, Saad Ali

    2015-12-01

    KMeans clustering-based recommendation algorithms have been proposed claiming to increase the scalability of recommender systems. One potential drawback of these algorithms is that they perform training offline and hence cannot accommodate the incremental updates with the arrival of new data, making them unsuitable for the dynamic environments. From this line of research, a new clustering algorithm called One-Pass is proposed, which is a simple, fast, and accurate. We show empirically that the proposed algorithm outperforms K-Means in terms of recommendation and training time while maintaining a good level of accuracy.

  1. A Two-Pass Exact Algorithm for Selection on Parallel Disk Systems

    PubMed Central

    Mi, Tian; Rajasekaran, Sanguthevar

    2014-01-01

    Numerous OLAP queries process selection operations of “top N”, median, “top 5%”, in data warehousing applications. Selection is a well-studied problem that has numerous applications in the management of data and databases since, typically, any complex data query can be reduced to a series of basic operations such as sorting and selection. The parallel selection has also become an important fundamental operation, especially after parallel databases were introduced. In this paper, we present a deterministic algorithm Recursive Sampling Selection (RSS) to solve the exact out-of-core selection problem, which we show needs no more than (2 + ε) passes (ε being a very small fraction). We have compared our RSS algorithm with two other algorithms in the literature, namely, the Deterministic Sampling Selection and QuickSelect on the Parallel Disks Systems. Our analysis shows that DSS is a (2 + ε)-pass algorithm when the total number of input elements N is a polynomial in the memory size M (i.e., N = Mc for some constant c). While, our proposed algorithm RSS runs in (2 + ε) passes without any assumptions. Experimental results indicate that both RSS and DSS outperform QuickSelect on the Parallel Disks Systems. Especially, the proposed algorithm RSS is more scalable and robust to handle big data when the input size is far greater than the core memory size, including the case of N ≫ Mc. PMID:25374478

  2. Temporal high-pass non-uniformity correction algorithm based on grayscale mapping and hardware implementation

    NASA Astrophysics Data System (ADS)

    Jin, Minglei; Jin, Weiqi; Li, Yiyang; Li, Shuo

    2015-08-01

    In this paper, we propose a novel scene-based non-uniformity correction algorithm for infrared image processing-temporal high-pass non-uniformity correction algorithm based on grayscale mapping (THP and GM). The main sources of non-uniformity are: (1) detector fabrication inaccuracies; (2) non-linearity and variations in the read-out electronics and (3) optical path effects. The non-uniformity will be reduced by non-uniformity correction (NUC) algorithms. The NUC algorithms are often divided into calibration-based non-uniformity correction (CBNUC) algorithms and scene-based non-uniformity correction (SBNUC) algorithms. As non-uniformity drifts temporally, CBNUC algorithms must be repeated by inserting a uniform radiation source which SBNUC algorithms do not need into the view, so the SBNUC algorithm becomes an essential part of infrared imaging system. The SBNUC algorithms' poor robustness often leads two defects: artifacts and over-correction, meanwhile due to complicated calculation process and large storage consumption, hardware implementation of the SBNUC algorithms is difficult, especially in Field Programmable Gate Array (FPGA) platform. The THP and GM algorithm proposed in this paper can eliminate the non-uniformity without causing defects. The hardware implementation of the algorithm only based on FPGA has two advantages: (1) low resources consumption, and (2) small hardware delay: less than 20 lines, it can be transplanted to a variety of infrared detectors equipped with FPGA image processing module, it can reduce the stripe non-uniformity and the ripple non-uniformity.

  3. Phase Response Design of Recursive All-Pass Digital Filters Using a Modified PSO Algorithm

    PubMed Central

    Chang, Wei-Der

    2015-01-01

    This paper develops a new design scheme for the phase response of an all-pass recursive digital filter. A variant of particle swarm optimization (PSO) algorithm will be utilized for solving this kind of filter design problem. It is here called the modified PSO (MPSO) algorithm in which another adjusting factor is more introduced in the velocity updating formula of the algorithm in order to improve the searching ability. In the proposed method, all of the designed filter coefficients are firstly collected to be a parameter vector and this vector is regarded as a particle of the algorithm. The MPSO with a modified velocity formula will force all particles into moving toward the optimal or near optimal solution by minimizing some defined objective function of the optimization problem. To show the effectiveness of the proposed method, two different kinds of linear phase response design examples are illustrated and the general PSO algorithm is compared as well. The obtained results show that the MPSO is superior to the general PSO for the phase response design of digital recursive all-pass filter. PMID:26366168

  4. AUTOmatic Message PACKing Facility

    Energy Science and Technology Software Center (ESTSC)

    2004-07-01

    AUTOPACK is a library that provides several useful features for programs using the Message Passing Interface (MPI). Features included are: 1. automatic message packing facility 2. management of send and receive requests. 3. management of message buffer memory. 4. determination of the number of anticipated messages from a set of arbitrary sends, and 5. deterministic message delivery for testing purposes.

  5. Scaling and performance of a 3-D radiation hydrodynamics code on message-passing parallel computers: final report

    SciTech Connect

    Hayes, J C; Norman, M

    1999-10-28

    This report details an investigation into the efficacy of two approaches to solving the radiation diffusion equation within a radiation hydrodynamic simulation. Because leading-edge scientific computing platforms have evolved from large single-node vector processors to parallel aggregates containing tens to thousands of individual CPU's, the ability of an algorithm to maintain high compute efficiency when distributed over a large array of nodes is critically important. The viability of an algorithm thus hinges upon the tripartite question of numerical accuracy, total time to solution, and parallel efficiency.

  6. One-Sided Communication on the Myrinet-Based SMP Clusters Using the GM Message-Passing Library

    SciTech Connect

    Nieplocha, Jaroslaw; Ju, Jialin; Apra, Edoardo

    2001-12-07

    he paper describes an efficient implementation of one-sided communication on top of GM messagre passing library and Pthreads for the Myrinet-based SMP clusters. This approach avoids polling, is compatible with shared memory, and exploits pipelining, nonblocking communication, and overlapping memory registration with memory copy to maximize the transfer rate. Our implementation uses the standard distribution of GM and is compatible with MPICH/GM. Performance of our two applications was very good, and the GM port allowed them to avoid performance anomalies of the standard TCP/IP implementation when running on Myrinet.

  7. Optimal message log reclamation for uncoordinated checkpointing

    NASA Technical Reports Server (NTRS)

    Wang, Yi-Min; Fuchs, W. K.

    1994-01-01

    Uncoordinated checkpointing for message-passing systems allows maximum process autonomy and general nondeterministic execution, but suffers from potential domino effect and the large space overhead for maintaining checkpoints and message logs. Traditionally, it has been assumed that only obsolete checkpoints and message logs before the global recovery line can be garbage-collected. Recently, an approach to identifying all garbage checkpoints based on recovery line transformation and decomposition has been developed. We show in this paper that the same approach can be applied to the problem of identifying all garbage message logs for systems requiring message logging to record in-transit messages. Communication trace-driven simulation for several parallel programs is used to evaluate the proposed algorithm.

  8. An algorithm used for quality criterion automatic measurement of band-pass filters and its device implementation

    NASA Astrophysics Data System (ADS)

    Liu, Qianshun; Liu, Yan; Yu, Feihong

    2013-08-01

    As a kind of film device, band-pass filter is widely used in pattern recognition, infrared detection, optical fiber communication, etc. In this paper, an algorithm for automatic measurement of band-pass filter quality criterion is proposed based on the proven theory calculation of derivate spectral transmittance of filter formula. Firstly, wavelet transform to reduce spectrum data noises is used. Secondly, combining with the Gaussian curve fitting and least squares method, the algorithm fits spectrum curve and searches the peak. Finally, some parameters for judging band-pass filter quality are figure out. Based on the algorithm, a pipeline for band-pass filters automatic measurement system has been designed that can scan the filter array automatically and display spectral transmittance of each filter. At the same time, the system compares the measuring result with the user defined standards to determine if the filter is qualified or not. The qualified product will be market with green color, and the unqualified product will be marked with red color. With the experiments verification, the automatic measurement system basically realized comprehensive, accurate and rapid measurement of band-pass filter quality and achieved the expected results.

  9. Multiple node remote messaging

    DOEpatents

    Blumrich, Matthias A.; Chen, Dong; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Ohmacht, Martin; Salapura, Valentina; Steinmacher-Burow, Burkhard; Vranas, Pavlos

    2010-08-31

    A method for passing remote messages in a parallel computer system formed as a network of interconnected compute nodes includes that a first compute node (A) sends a single remote message to a remote second compute node (B) in order to control the remote second compute node (B) to send at least one remote message. The method includes various steps including controlling a DMA engine at first compute node (A) to prepare the single remote message to include a first message descriptor and at least one remote message descriptor for controlling the remote second compute node (B) to send at least one remote message, including putting the first message descriptor into an injection FIFO at the first compute node (A) and sending the single remote message and the at least one remote message descriptor to the second compute node (B).

  10. Development of an HL7 interface engine, based on tree structure and streaming algorithm, for large-size messages which include image data.

    PubMed

    Um, Ki Sung; Kwak, Yun Sik; Cho, Hune; Kim, Il Kon

    2005-11-01

    A basic assumption of Health Level Seven (HL7) protocol is 'No limitation of message length'. However, most existing commercial HL7 interface engines do limit message length because they use the string array method, which is run in the main memory for the HL7 message parsing process. Specifically, messages with image and multi-media data create a long string array and thus cause the computer system to raise critical and fatal problem. Consequently, HL7 messages cannot handle the image and multi-media data necessary in modern medical records. This study aims to solve this problem with the 'streaming algorithm' method. This new method for HL7 message parsing applies the character-stream object which process character by character between the main memory and hard disk device with the consequence that the processing load on main memory could be alleviated. The main functions of this new engine are generating, parsing, validating, browsing, sending, and receiving HL7 messages. Also, the engine can parse and generate XML-formatted HL7 messages. This new HL7 engine successfully exchanged HL7 messages with 10 megabyte size images and discharge summary information between two university hospitals. PMID:16181703

  11. Improved Noise Minimum Statistics Estimation Algorithm for Using in a Speech-Passing Noise-Rejecting Headset

    NASA Astrophysics Data System (ADS)

    Seyedtabaee, Saeed; Moazami Goodarzi, Hamze

    2010-12-01

    This paper deals with configuration of an algorithm to be used in a speech-passing angle grinder noise-canceling headset. Angle grinder noise is annoying and interrupts ordinary oral communication. Meaning that, low SNR noisy condition is ahead. Since variation in angle grinder working condition changes noise statistics, the noise will be nonstationary with possible jumps in its power. Studies are conducted for picking an appropriate algorithm. A modified version of the well-known spectral subtraction shows superior performance against alternate methods. Noise estimation is calculated through a multi-band fast adapting scheme. The algorithm is adapted very quickly to the non-stationary noise environment while inflecting minimum musical noise and speech distortion on the processed signal. Objective and subjective measures illustrating the performance of the proposed method are introduced.

  12. Compared performance of different centroiding algorithms for high-pass filtered laser guide star Shack-Hartmann wavefront sensors

    NASA Astrophysics Data System (ADS)

    Lardière, Olivier; Conan, Rodolphe; Clare, Richard; Bradley, Colin; Hubin, Norbert

    2010-07-01

    Variations of the sodium layer altitude and atom density profile induce errors on laser-guide-star (LGS) adaptive optics systems. These errors must be mitigated by (i), optimizing the LGS wavefront sensor (WFS) and the centroiding algorithm, and (ii), by adding a high-pass filter on the LGS path and a low-bandwidth natural-guide-star WFS. In the context of the ESO E-ELT project, five centroiding algorithms, namely the centre-of-gravity (CoG), the weighted CoG, the matched filter, the quad-cell and the correlation, have been evaluated in closedloop on the University of Victoria LGS wavefront sensing test bed. Each centroiding algorithm performance is compared for a central versus side-launch laser, different fields of view, pixel sampling, and LGS flux.

  13. Effects of spectrometer band pass, sampling, and signal-to-noise ratio on spectral identification using the Tetracorder algorithm

    NASA Astrophysics Data System (ADS)

    Swayze, Gregg A.; Clark, Roger N.; Goetz, Alexander F. H.; Chrien, Thomas G.; Gorelick, Noel S.

    2003-09-01

    Estimates of spectrometer band pass, sampling interval, and signal-to-noise ratio required for identification of pure minerals and plants were derived using reflectance spectra convolved to AVIRIS, HYDICE, MIVIS, VIMS, and other imaging spectrometers. For each spectral simulation, various levels of random noise were added to the reflectance spectra after convolution, and then each was analyzed with the Tetracorder spectral identification algorithm [Clark et al., 2003]. The outcome of each identification attempt was tabulated to provide an estimate of the signal-to-noise ratio at which a given percentage of the noisy spectra were identified correctly. Results show that spectral identification is most sensitive to the signal-to-noise ratio at narrow sampling interval values but is more sensitive to the sampling interval itself at broad sampling interval values because of spectral aliasing, a condition when absorption features of different materials can resemble one another. The band pass is less critical to spectral identification than the sampling interval or signal-to-noise ratio because broadening the band pass does not induce spectral aliasing. These conclusions are empirically corroborated by analysis of mineral maps of AVIRIS data collected at Cuprite, Nevada, between 1990 and 1995, a period during which the sensor signal-to-noise ratio increased up to sixfold. There are values of spectrometer sampling and band pass beyond which spectral identification of materials will require an abrupt increase in sensor signal-to-noise ratio due to the effects of spectral aliasing. Factors that control this threshold are the uniqueness of a material's diagnostic absorptions in terms of shape and wavelength isolation, and the spectral diversity of the materials found in nature and in the spectral library used for comparison. Array spectrometers provide the best data for identification when they critically sample spectra. The sampling interval should not be broadened to

  14. Effects of spectrometer band pass, sampling, and signal-to-noise ratio on spectral identification using the Tetracorder algorithm

    USGS Publications Warehouse

    Swayze, G.A.; Clark, R.N.; Goetz, A.F.H.; Chrien, T.H.; Gorelick, N.S.

    2003-01-01

    Estimates of spectrometer band pass, sampling interval, and signal-to-noise ratio required for identification of pure minerals and plants were derived using reflectance spectra convolved to AVIRIS, HYDICE, MIVIS, VIMS, and other imaging spectrometers. For each spectral simulation, various levels of random noise were added to the reflectance spectra after convolution, and then each was analyzed with the Tetracorder spectra identification algorithm [Clark et al., 2003]. The outcome of each identification attempt was tabulated to provide an estimate of the signal-to-noise ratio at which a given percentage of the noisy spectra were identified correctly. Results show that spectral identification is most sensitive to the signal-to-noise ratio at narrow sampling interval values but is more sensitive to the sampling interval itself at broad sampling interval values because of spectral aliasing, a condition when absorption features of different materials can resemble one another. The band pass is less critical to spectral identification than the sampling interval or signal-to-noise ratio because broadening the band pass does not induce spectral aliasing. These conclusions are empirically corroborated by analysis of mineral maps of AVIRIS data collected at Cuprite, Nevada, between 1990 and 1995, a period during which the sensor signal-to-noise ratio increased up to sixfold. There are values of spectrometer sampling and band pass beyond which spectral identification of materials will require an abrupt increase in sensor signal-to-noise ratio due to the effects of spectral aliasing. Factors that control this threshold are the uniqueness of a material's diagnostic absorptions in terms of shape and wavelength isolation, and the spectral diversity of the materials found in nature and in the spectral library used for comparison. Array spectrometers provide the best data for identification when they critically sample spectra. The sampling interval should not be broadened to

  15. Simple Algorithms for Distributed Leader Election in Anonymous Synchronous Rings and Complete Networks Inspired by Neural Development in Fruit Flies.

    PubMed

    Xu, Lei; Jeavons, Peter

    2015-11-01

    Leader election in anonymous rings and complete networks is a very practical problem in distributed computing. Previous algorithms for this problem are generally designed for a classical message passing model where complex messages are exchanged. However, the need to send and receive complex messages makes such algorithms less practical for some real applications. We present some simple synchronous algorithms for distributed leader election in anonymous rings and complete networks that are inspired by the development of the neural system of the fruit fly. Our leader election algorithms all assume that only one-bit messages are broadcast by nodes in the network and processors are only able to distinguish between silence and the arrival of one or more messages. These restrictions allow implementations to use a simpler message-passing architecture. Even with these harsh restrictions our algorithms are shown to achieve good time and message complexity both analytically and experimentally. PMID:26173905

  16. Computations of two passing-by high-speed trains by a relaxation overset-grid algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Jenn-Long

    2004-04-01

    This paper presents a relaxation algorithm, which is based on the overset grid technology, an unsteady three-dimensional Navier-Stokes flow solver, and an inner- and outer-relaxation method, for simulation of the unsteady flows of moving high-speed trains. The flow solutions on the overlapped grids can be accurately updated by introducing a grid tracking technique and the inner- and outer-relaxation method. To evaluate the capability and solution accuracy of the present algorithm, the computational static pressure distribution of a single stationary TGV high-speed train inside a long tunnel is investigated numerically, and is compared with the experimental data from low-speed wind tunnel test. Further, the unsteady flows of two TGV high-speed trains passing by each other inside a long tunnel and at the tunnel entrance are simulated. A series of time histories of pressure distributions and aerodynamic loads acting on the train and tunnel surfaces are depicted for detailed discussions.

  17. Dynamic Message Routing Using Processes

    NASA Astrophysics Data System (ADS)

    Scheibler, Thorsten; Karastoyanova, Dimka; Leymann, Frank

    The Enterprise Service Bus (ESB) is composable middleware that provides applications with services such as message routing and transformation, service composition, dynamic discovery, transactional support, coordination, security features, and others. In an ESB supporting SOAP message exchange, routing algorithms typically follow the sequential SOAP message processing model, where SOAP headers are the main artefacts used to specify the message route and the processing of the payload by intermediaries along that route. This model supports neither alternative nor parallel message routes. In the case of a failing intermediary node this leads to a failure in the message delivery. Moreover, the execution order of services on SOAP message payloads at the intermediaries cannot be prescribed. In this paper, we demonstrate how these deficiencies of the SOAP message processing model can be addressed. We introduce an approach that allows for specifying SOAP message routing logic in terms of BPEL processes. We show that parallel and alternative routes for SOAP messages can be modelled and executed, and the order of services that process a message at intermediaries can be predefined to accommodate the correct processing sequence as required by the concrete application domain. Features like dynamic discovery of services and flexible service composition are leveraged to enable flexible SOAP message routing.

  18. President's Message

    ERIC Educational Resources Information Center

    Stephenson, Andy

    2007-01-01

    In this message from the International Technology Education Association (ITEA) president, Andy Stephenson stresses the need for technology, innovation, design, and engineering (TIDE) education. He cites the recent report--"Preparing for the Perfect Storm, a Report on the Forum, Taking Action Together: Developing a National Plan to Address the "T &…

  19. Parameter optimization for a high-order band-pass continuous-time sigma-delta modulator MEMS gyroscope using a genetic algorithm approach

    NASA Astrophysics Data System (ADS)

    Chen, Fang; Chang, Honglong; Yuan, Weizheng; Wilcock, Reuben; Kraft, Michael

    2012-10-01

    This paper describes a novel multiobjective parameter optimization method based on a genetic algorithm (GA) for the design of a sixth-order continuous-time, force feedback band-pass sigma-delta modulator (BP-ΣΔM) interface for the sense mode of a MEMS gyroscope. The design procedure starts by deriving a parameterized Simulink model of the BP-ΣΔM gyroscope interface. The system parameters are then optimized by the GA. Consequently, the optimized design is tested for robustness by a Monte Carlo analysis to find a solution that is both optimal and robust. System level simulations result in a signal-to-noise ratio (SNR) larger than 90 dB in a bandwidth of 64 Hz with a 200° s-1 angular rate input signal; the noise floor is about -100 dBV Hz-1/2. The simulations are compared to measured data from a hardware implementation. For zero input rotation with the gyroscope operating at atmospheric pressure, the spectrum of the output bitstream shows an obvious band-pass noise shaping and a deep notch at the gyroscope resonant frequency. The noise floor of measured power spectral density (PSD) of the output bitstream agrees well with simulation of the optimized system level model. The bias stability, rate sensitivity and nonlinearity of the gyroscope controlled by an optimized BP-ΣΔM closed-loop interface are 34.15° h-1, 22.3 mV °-1 s-1, 98 ppm, respectively. This compares to a simple open-loop interface for which the corresponding values are 89° h-1, 14.3 mV °-1 s-1, 7600 ppm, and a nonoptimized BP-ΣΔM closed-loop interface with corresponding values of 60° h-1, 17 mV °-1 s-1, 200 ppm.

  20. Radiation transport calculations on unstructured grids using a spatially decomposed and threaded algorithm

    SciTech Connect

    Nemanic, M K; Nowak, P

    1999-04-12

    We consider the solution of time-dependent, energy-dependent, discrete ordinates, and nonlinear radiative transfer problems on three-dimensional unstructured spatial grids. We discuss the solution of this class of transport problems, using the code TETON, on large distributed-memory multinode computers having multiple processors per ''node'' (e.g. the IBM-SP). We discuss the use of both spatial decomposition using message passing between ''nodes'' and a threading algorithm in angle on each ''node''. We present timing studies to show how this algorithm scales to hundreds and thousands of processors. We also present an energy group ''batching'' algorithm that greatly enhances cache performance. Our conclusion, after considering cache performance, storage limitations and dependencies inherent in the physics, is that a model that uses a combination of message-passing and threading is superior to one that uses message-passing alone. We present numerical evidence to support our conclusion.

  1. Join-Graph Propagation Algorithms

    PubMed Central

    Mateescu, Robert; Kask, Kalev; Gogate, Vibhav; Dechter, Rina

    2010-01-01

    The paper investigates parameterized approximate message-passing schemes that are based on bounded inference and are inspired by Pearl's belief propagation algorithm (BP). We start with the bounded inference mini-clustering algorithm and then move to the iterative scheme called Iterative Join-Graph Propagation (IJGP), that combines both iteration and bounded inference. Algorithm IJGP belongs to the class of Generalized Belief Propagation algorithms, a framework that allowed connections with approximate algorithms from statistical physics and is shown empirically to surpass the performance of mini-clustering and belief propagation, as well as a number of other state-of-the-art algorithms on several classes of networks. We also provide insight into the accuracy of iterative BP and IJGP by relating these algorithms to well known classes of constraint propagation schemes. PMID:20740057

  2. Mixed messages

    PubMed Central

    Chen, Christopher B.; Hall, Kevin; Tsuyuki, Ross T.

    2014-01-01

    Background: More than 5 years ago, the Blueprint for Pharmacy developed a plan for transitioning pharmacy practice toward more patient-centred care. Much of the strategy for change involves communicating the new vision. Objective: To evaluate the communication of the Vision for Pharmacy by the organizations and corporations that signed the Blueprint for Pharmacy’s Commitment to Act. Methods: The list of 88 signatories of the Commitment to Act was obtained from the Blueprint for Pharmacy document. The website of each of these signatories was searched for all references to the Blueprint for Pharmacy or Vision for Pharmacy. Each of the identified references was then analyzed using summative content analysis. Results: A total of 934 references were identified from the webpages of the 88 signatories. Of these references, 549 were merely links to the Blueprint for Pharmacy’s website, 350 of the references provided some detailed information about the Blueprint for Pharmacy and only 35 references provided any specific plans to transition pharmacy practice. Conclusion: Widespread proliferation of the Vision for Pharmacy has not been achieved. One possible explanation for this is that communication of the vision by the signatories has been incomplete. To ensure the success of future communications, change leaders must develop strategies that consider how individual pharmacists and pharmacies understand the message. PMID:24660012

  3. Optimal message log reclamation for independent checkpointing

    NASA Technical Reports Server (NTRS)

    Wang, Yi-Min; Fuchs, W. Kent

    1993-01-01

    Independent (uncoordinated) check pointing for parallel and distributed systems allows maximum process autonomy but suffers from possible domino effects and the associated storage space overhead for maintaining multiple checkpoints and message logs. In most research on check pointing and recovery, it was assumed that only the checkpoints and message logs older than the global recovery line can be discarded. It is shown how recovery line transformation and decomposition can be applied to the problem of efficiently identifying all discardable message logs, thereby achieving optimal garbage collection. Communication trace-driven simulation for several parallel programs is used to show the benefits of the proposed algorithm for message log reclamation.

  4. Passing excellence

    NASA Astrophysics Data System (ADS)

    Tsoupikova, Daria

    2007-02-01

    This paper describes the research and development of a virtual reality visualization project "Passing excellence" about the world famous architectural ensemble "Kizhi". The Kizhi Pogost is located on an island in Lake Onega in northern Karelia in Russia. It is an authentic museum of an ancient wood building tradition which presents a unique artistic achievement. This ensemble preserves a concentration of masterpieces of the Russian heritage and is included in the List of Most Endangered Sites of the World Monuments Watch protected by World Heritage List of UNESCO. The project strives to create a unique virtual observation of the dynamics of the architectural changes of the museum area beginning from the 15th Century up to the 21st Century. The visualization is being created to restore the original architecture of Kizhi island based on the detailed photographs, architectural and geometric measurements, textural data, video surveys and resources from the Kizhi State Open-Air Museum archives. The project is being developed using Electro, an application development environment for the tiled display high-resolution graphics visualization system and can be shown on the virtual reality systems such as the GeoWall TM and the C-Wall.

  5. Full tensor gravity gradiometry data inversion: Performance analysis of parallel computing algorithms

    NASA Astrophysics Data System (ADS)

    Hou, Zhen-Long; Wei, Xiao-Hui; Huang, Da-Nian; Sun, Xu

    2015-09-01

    We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine MPI with CUDA to formulate a hybrid algorithm. Parallel computing performance metrics are introduced to analyze and compare the performance of the algorithms. We summarize the rules for the performance evaluation of parallel algorithms. We use model and real data from the Vinton salt dome to test the algorithms. We find good match between model and real density data, and verify the high efficiency and feasibility of parallel computing algorithms in the inversion of full tensor gravity gradiometry data.

  6. Data communications in a parallel active messaging interface of a parallel computer

    DOEpatents

    Davis, Kristan D.; Faraj, Daniel A.

    2014-07-22

    Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and ranges of message sizes so that each algorithm is associated with a separate range of message sizes; receiving in an origin endpoint of the PAMI a data communications instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint, the data communications message characterized by a message size; selecting, from among the associated algorithms and ranges, a data communications algorithm in dependence upon the message size; and transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

  7. Data communications in a parallel active messaging interface of a parallel computer

    DOEpatents

    Davis, Kristan D; Faraj, Daniel A

    2013-07-09

    Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and ranges of message sizes so that each algorithm is associated with a separate range of message sizes; receiving in an origin endpoint of the PAMI a data communications instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint, the data communications message characterized by a message size; selecting, from among the associated algorithms and ranges, a data communications algorithm in dependence upon the message size; and transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

  8. Preparing EBS messages

    SciTech Connect

    Vogt, B.M., Sorensen, J.H.

    1992-09-01

    Warning messages transmitted to populations at risk from an accidental release of chemical agent must be carefully designed to maximize appropriate responses from affected publics. This guide develops an approach for preparing Emergency Broadcast System (EBS) messages for the Chemical Stockpile Emergency Preparedness Program (CSEPP). Sample messages illustrate the application of this approach. While the sample messages do not cover every emergency situation, the texts are generic in that accident and location specific factors can be incorporated into the final message developed by local emergency planners. Thus they provide a starting point, not an end product, for emergency planners.

  9. Automated Performance Prediction of Message-Passing Parallel Programs

    NASA Technical Reports Server (NTRS)

    Block, Robert J.; Sarukkai, Sekhar; Mehra, Pankaj; Woodrow, Thomas S. (Technical Monitor)

    1995-01-01

    The increasing use of massively parallel supercomputers to solve large-scale scientific problems has generated a need for tools that can predict scalability trends of applications written for these machines. Much work has been done to create simple models that represent important characteristics of parallel programs, such as latency, network contention, and communication volume. But many of these methods still require substantial manual effort to represent an application in the model's format. The NIK toolkit described in this paper is the result of an on-going effort to automate the formation of analytic expressions of program execution time, with a minimum of programmer assistance. In this paper we demonstrate the feasibility of our approach, by extending previous work to detect and model communication patterns automatically, with and without overlapped computations. The predictions derived from these models agree, within reasonable limits, with execution times of programs measured on the Intel iPSC/860 and Paragon. Further, we demonstrate the use of MK in selecting optimal computational grain size and studying various scalability metrics.

  10. Increasing fault resiliency in a message-passing environment.

    SciTech Connect

    Stearley, Jon R.; Riesen, Rolf E.; Laros, James H., III; Ferreira, Kurt Brian; Pedretti, Kevin Thomas Tauke; Oldfield, Ron A.; Kordenbrock, Todd; Brightwell, Ronald Brian

    2009-10-01

    Petaflops systems will have tens to hundreds of thousands of compute nodes which increases the likelihood of faults. Applications use checkpoint/restart to recover from these faults, but even under ideal conditions, applications running on more than 30,000 nodes will likely spend more than half of their total run time saving checkpoints, restarting, and redoing work that was lost. We created a library that performs redundant computations on additional nodes allocated to the application. An active node and its redundant partner form a node bundle which will only fail, and cause an application restart, when both nodes in the bundle fail. The goal of this library is to learn whether this can be done entirely at the user level, what requirements this library places on a Reliability, Availability, and Serviceability (RAS) system, and what its impact on performance and run time is. We find that our redundant MPI layer library imposes a relatively modest performance penalty for applications, but that it greatly reduces the number of applications interrupts. This reduction in interrupts leads to huge savings in restart and rework time. For large-scale applications the savings compensate for the performance loss and the additional nodes required for redundant computations.

  11. Information Management and Learning in Computer Conferences: Coping with Irrelevant and Unconnected Messages.

    ERIC Educational Resources Information Center

    Schwan, Stephan; Straub, Daniela; Hesse, Friedrich W.

    2002-01-01

    Describes a study of computer conferencing where learners interacted over the course of four log-in sessions to acquire the knowledge sufficient to pass a learning test. Studied the number of messages irrelevant to the topic, explicit threading of messages, reading times of relevant messages, and learning outcomes. (LRW)

  12. Scalable Replay with Partial-Order Dependencies for Message-Logging Fault Tolerance

    SciTech Connect

    Lifflander, Jonathan; Meneses, Esteban; Menon, Harshita; Miller, Phil; Krishnamoorthy, Sriram; Kale, Laxmikant

    2014-09-22

    Deterministic replay of a parallel application is commonly used for discovering bugs or to recover from a hard fault with message-logging fault tolerance. For message passing programs, a major source of overhead during forward execution is recording the order in which messages are sent and received. During replay, this ordering must be used to deterministically reproduce the execution. Previous work in replay algorithms often makes minimal assumptions about the programming model and application in order to maintain generality. However, in many cases, only a partial order must be recorded due to determinism intrinsic in the code, ordering constraints imposed by the execution model, and events that are commutative (their relative execution order during replay does not need to be reproduced exactly). In this paper, we present a novel algebraic framework for reasoning about the minimum dependencies required to represent the partial order for different concurrent orderings and interleavings. By exploiting this theory, we improve on an existing scalable message-logging fault tolerance scheme. The improved scheme scales to 131,072 cores on an IBM BlueGene/P with up to 2x lower overhead than one that records a total order.

  13. Error message recording and reporting in the SLC control system

    SciTech Connect

    Spencer, N.; Bogart, J.; Phinney, N.; Thompson, K.

    1985-04-01

    Error or information messages that are signaled by control software either in the VAX host computer or the local microprocessor clusters are handled by a dedicated VAX process (PARANOIA). Messages are recorded on disk for further analysis and displayed at the appropriate console. Another VAX process (ERRLOG) can be used to sort, list and histogram various categories of messages. The functions performed by these processes and the algorithms used are discussed.

  14. Launching Family Message Journals.

    ERIC Educational Resources Information Center

    Wollman-Bonilla, Julie

    This lesson introduces Family Message Journals, a tool for encouraging family involvement and supporting writing to reflect and learn. First and second graders are led into composing through demonstration, guided writing, and finally independent writing of messages that they will bring home for family to read and write a reply. During the three…

  15. Message in a molecule.

    PubMed

    Sarkar, Tanmay; Selvakumar, Karuthapandi; Motiei, Leila; Margulies, David

    2016-01-01

    Since ancient times, steganography, the art of concealing information, has largely relied on secret inks as a tool for hiding messages. However, as the methods for detecting these inks improved, the use of simple and accessible chemicals as a means to secure communication was practically abolished. Here, we describe a method that enables one to conceal multiple different messages within the emission spectra of a unimolecular fluorescent sensor. Similar to secret inks, this molecular-scale messaging sensor (m-SMS) can be hidden on regular paper and the messages can be encoded or decoded within seconds using common chemicals, including commercial ingredients that can be obtained in grocery stores or pharmacies. Unlike with invisible inks, however, uncovering these messages by an unauthorized user is almost impossible because they are protected by three different defence mechanisms: steganography, cryptography and by entering a password, which are used to hide, encrypt or prevent access to the information, respectively. PMID:27138465

  16. Message in a molecule

    PubMed Central

    Sarkar, Tanmay; Selvakumar, Karuthapandi; Motiei, Leila; Margulies, David

    2016-01-01

    Since ancient times, steganography, the art of concealing information, has largely relied on secret inks as a tool for hiding messages. However, as the methods for detecting these inks improved, the use of simple and accessible chemicals as a means to secure communication was practically abolished. Here, we describe a method that enables one to conceal multiple different messages within the emission spectra of a unimolecular fluorescent sensor. Similar to secret inks, this molecular-scale messaging sensor (m-SMS) can be hidden on regular paper and the messages can be encoded or decoded within seconds using common chemicals, including commercial ingredients that can be obtained in grocery stores or pharmacies. Unlike with invisible inks, however, uncovering these messages by an unauthorized user is almost impossible because they are protected by three different defence mechanisms: steganography, cryptography and by entering a password, which are used to hide, encrypt or prevent access to the information, respectively. PMID:27138465

  17. Passing crisis and emergency risk communications: the effects of communication channel, information type, and repetition.

    PubMed

    Edworthy, Judy; Hellier, Elizabeth; Newbold, Lex; Titchener, Kirsteen

    2015-05-01

    Three experiments explore several factors which influence information transmission when warning messages are passed from person to person. In Experiment 1, messages were passed down chains of participants using five different modes of communication. Written communication channels resulted in more accurate message transmission than verbal. In addition, some elements of the message endured further down the chain than others. Experiment 2 largely replicated these effects and also demonstrated that simple repetition of a message eliminated differences between written and spoken communication. In a final field experiment, chains of participants passed information however they wanted to, with the proviso that half of the chains could not use telephones. Here, the lack of ability to use a telephone did not affect accuracy, but did slow down the speed of transmission from the recipient of the message to the last person in the chain. Implications of the findings for crisis and emergency risk communication are discussed. PMID:25683552

  18. Expedition 34 Thanksgiving Message

    NASA Video Gallery

    Expedition 34 Commander Kevin Ford shares a Thanksgiving message from the International Space Station. Ford demonstrates how the crew will spend the holiday on orbit and describes the menu he and h...

  19. The Prodiguer Messaging Platform

    NASA Astrophysics Data System (ADS)

    Greenslade, Mark; Denvil, Sebastien; Raciazek, Jerome; Carenton, Nicolas; Levavasseur, Guillame

    2014-05-01

    CONVERGENCE is a French multi-partner national project designed to gather HPC and informatics expertise to innovate in the context of running French climate models with differing grids and at differing resolutions. Efficient and reliable execution of these models and the management and dissemination of model output (data and meta-data) are just some of the complexities that CONVERGENCE aims to resolve. The Institut Pierre Simon Laplace (IPSL) is responsible for running climate simulations upon a set of heterogenous HPC environments within France. With heterogeneity comes added complexity in terms of simulation instrumentation and control. Obtaining a global perspective upon the state of all simulations running upon all HPC environments has hitherto been problematic. In this presentation we detail how, within the context of CONVERGENCE, the implementation of the Prodiguer messaging platform resolves complexity and permits the development of real-time applications such as: 1. a simulation monitoring dashboard; 2. a simulation metrics visualizer; 3. an automated simulation runtime notifier; 4. an automated output data & meta-data publishing pipeline; The Prodiguer messaging platform leverages a widely used open source message broker software called RabbitMQ. RabbitMQ itself implements the Advanced Message Queue Protocol (AMPQ). Hence it will be demonstrated that the Prodiguer messaging platform is built upon both open source and open standards.

  20. LBNL SecureMessaging

    SciTech Connect

    Pery, Marcia; Agarwal, Deb

    2003-03-17

    The LBNLSecureMessaging application enables collaboration among colocated or geograhically dispersed users by supporting secure synchronous and asynchronous communication. This application is the graphical user interface client that is meant to be used in conjunction with servers (LBNL's PCCEServer and a customized IRC server) to allow group and one-to-one conversations via text-based instant messaging. Conversations may be private (by invitation only) or public (open to any member of a collaboratory group_ and they may be permanent and on-going or temporary and ad hoc. Users may leave notes for other people who are online or offline. By providing presence and awareness information, collaborators can easily locate each other and rendezvous. Written in Java/Swing, this application is cross-platform. To gain access to functionality, users have to be registered with an authorization server (PCCEServer) that maintains an access control list. Thus a collaboration group is comprised of a set of PCCE-registered users. Registered users can log in via either X.509 certificate or a username and password combination. PKI and SSL are used to authenticate servers and clients and to encrypt messages sent over the network. The LBNLSecureMessaging application offers instant messaging capabilities in a secure environment that provides data integrity, privacyk authorization, and authentication.

  1. LBNL SecureMessaging

    Energy Science and Technology Software Center (ESTSC)

    2003-03-17

    The LBNLSecureMessaging application enables collaboration among colocated or geograhically dispersed users by supporting secure synchronous and asynchronous communication. This application is the graphical user interface client that is meant to be used in conjunction with servers (LBNL's PCCEServer and a customized IRC server) to allow group and one-to-one conversations via text-based instant messaging. Conversations may be private (by invitation only) or public (open to any member of a collaboratory group_ and they may be permanentmore » and on-going or temporary and ad hoc. Users may leave notes for other people who are online or offline. By providing presence and awareness information, collaborators can easily locate each other and rendezvous. Written in Java/Swing, this application is cross-platform. To gain access to functionality, users have to be registered with an authorization server (PCCEServer) that maintains an access control list. Thus a collaboration group is comprised of a set of PCCE-registered users. Registered users can log in via either X.509 certificate or a username and password combination. PKI and SSL are used to authenticate servers and clients and to encrypt messages sent over the network. The LBNLSecureMessaging application offers instant messaging capabilities in a secure environment that provides data integrity, privacyk authorization, and authentication.« less

  2. Optimizing Adherence Through Provider and Patient Messaging.

    PubMed

    Millman, Mark D; Den Hartog, Kevin S

    2016-08-01

    Health care organizations continue to look for cost-effective ways to modify patient behaviors toward a healthier lifestyle, including improving compliance with evidence-based treatment guidelines. This study evaluated the impact on compliance to evidence-based guidelines associated with a member messaging program (MMP) that is delivered via hard copy through the mail and also electronically via web portals. Anonymized member data were reviewed using disease-specific algorithms designed to find gaps in evidence-based care. Gap closure was monitored over a 6-month period after identification and was the main outcome under study. MMP members received at least 1 message describing a specific gap in care identified via claims data. In addition, if a match was possible, the same message also was sent to the member's physician. MMP members were then compared to a cohort not receiving messages but having the same gaps in care. Multiple regression analysis was performed using a generalized linear model with gap closure as the outcome to infer the relationship between receiving a notification and closing a gap in care. Of the 140 gaps addressed in the study, 23 showed a statistically significant (P < 0.05) difference in gap closure rates between the messaged group and the non-messaged group. Diabetes-related gap closures accounted for 10 of the 23 significant outcomes. Messages notifying of a gap in care can influence member health care adherence to evidence-based guidelines, particularly with diabetes-related gaps in care. (Population Health Management 2016;19:264-271). PMID:26451807

  3. A parallelization of the row-searching algorithm

    NASA Astrophysics Data System (ADS)

    Yaici, Malika; Khaled, Hayet; Khaled, Zakia; Bentahar, Athmane

    2012-11-01

    The problem dealt in this paper concerns the parallelization of the row-searching algorithm which allows the search for linearly dependant rows on a given matrix and its implementation on MPI (Message Passing Interface) environment. This algorithm is largely used in control theory and more specifically in solving the famous diophantine equation. An introduction to the diophantine equation is presented, then two parallelization approaches of the algorithm are detailed. The first distributes a set of rows on processes (processors) and the second makes a distribution per blocks. The sequential algorithm and its two parallel forms are implemented using MPI routines, then modelled using UML (Unified Modelling Language) and finally evaluated using algorithmic complexity.

  4. Authentication of quantum messages.

    SciTech Connect

    Barnum, Howard; Crépeau, Jean-Claude; Gottesman, D.; Smith, A.; Tapp, Alan

    2001-01-01

    Authentication is a well-studied area of classical cryptography: a sender A and a receiver B sharing a classical private key want to exchange a classical message with the guarantee that the message has not been modified or replaced by a dishonest party with control of the communication line. In this paper we study the authentication of messages composed of quantum states. We give a formal definition of authentication in the quantum setting. Assuming A and B have access to an insecure quantum channel and share a private, classical random key, we provide a non-interactive scheme that both enables A to encrypt and authenticate (with unconditional security) an m qubit message by encoding it into m + s qubits, where the probability decreases exponentially in the security parameter s. The scheme requires a private key of size 2m + O(s). To achieve this, we give a highly efficient protocol for testing the purity of shared EPR pairs. It has long been known that learning information about a general quantum state will necessarily disturb it. We refine this result to show that such a disturbance can be done with few side effects, allowing it to circumvent cryptographic protections. Consequently, any scheme to authenticate quantum messages must also encrypt them. In contrast, no such constraint exists classically: authentication and encryption are independent tasks, and one can authenticate a message while leaving it publicly readable. This reasoning has two important consequences: On one hand, it allows us to give a lower bound of 2m key bits for authenticating m qubits, which makes our protocol asymptotically optimal. On the other hand, we use it to show that digitally signing quantum states is impossible, even with only computational security.

  5. Increasing the Operational Value of Event Messages

    NASA Technical Reports Server (NTRS)

    Li, Zhenping; Savkli, Cetin; Smith, Dan

    2003-01-01

    Assessing the health of a space mission has traditionally been performed using telemetry analysis tools. Parameter values are compared to known operational limits and are plotted over various time periods. This presentation begins with the notion that there is an incredible amount of untapped information contained within the mission s event message logs. Through creative advancements in message handling tools, the event message logs can be used to better assess spacecraft and ground system status and to highlight and report on conditions not readily apparent when messages are evaluated one-at-a-time during a real-time pass. Work in this area is being funded as part of a larger NASA effort at the Goddard Space Flight Center to create component-based, middleware-based, standards-based general purpose ground system architecture referred to as GMSEC - the GSFC Mission Services Evolution Center. The new capabilities and operational concepts for event display, event data analyses and data mining are being developed by Lockheed Martin and the new subsystem has been named GREAT - the GMSEC Reusable Event Analysis Toolkit. Planned for use on existing and future missions, GREAT has the potential to increase operational efficiency in areas of problem detection and analysis, general status reporting, and real-time situational awareness.

  6. YAMPA: Yet Another Matching Pursuit Algorithm for compressive sensing

    NASA Astrophysics Data System (ADS)

    Lodhi, Muhammad A.; Voronin, Sergey; Bajwa, Waheed U.

    2016-05-01

    State-of-the-art sparse recovery methods often rely on the restricted isometry property for their theoretical guarantees. However, they cannot explicitly incorporate metrics such as restricted isometry constants within their recovery procedures due to the computational intractability of calculating such metrics. This paper formulates an iterative algorithm, termed yet another matching pursuit algorithm (YAMPA), for recovery of sparse signals from compressive measurements. YAMPA differs from other pursuit algorithms in that: (i) it adapts to the measurement matrix using a threshold that is explicitly dependent on two computable coherence metrics of the matrix, and (ii) it does not require knowledge of the signal sparsity. Performance comparisons of YAMPA against other matching pursuit and approximate message passing algorithms are made for several types of measurement matrices. These results show that while state-of-the-art approximate message passing algorithms outperform other algorithms (including YAMPA) in the case of well-conditioned random matrices, they completely break down in the case of ill-conditioned measurement matrices. On the other hand, YAMPA and comparable pursuit algorithms not only result in reasonable performance for well-conditioned matrices, but their performance also degrades gracefully for ill-conditioned matrices. The paper also shows that YAMPA uniformly outperforms other pursuit algorithms for the case of thresholding parameters chosen in a clairvoyant fashion. Further, when combined with a simple and fast technique for selecting thresholding parameters in the case of ill-conditioned matrices, YAMPA outperforms other pursuit algorithms in the regime of low undersampling, although some of these algorithms can outperform YAMPA in the regime of high undersampling in this setting.

  7. A System for Exchanging Control and Status Messages in the NOvA Data Acquisition

    SciTech Connect

    Biery, K.A.; Cooper, R.G.; Foulkes, S.C.; Guglielmo, G.M.; Piccoli, L.P.; Votava, M.E.V.; /Fermilab

    2007-04-01

    In preparation for NOvA, a future neutrino experiment at Fermilab, we are developing a system for passing control and status messages in the data acquisition system. The DAQ system will consist of applications running on approximately 450 nodes. The message passing system will use a publish-subscribe model and will provide support for sending messages and receiving the associated replies. Additional features of the system include a layered architecture with custom APIs tailored to the needs of a DAQ system, the use of an open source messaging system for handling the reliable delivery of messages, the ability to send broadcasts to groups of applications, and APIs in Java, C++, and Python. Our choice for the open source system to deliver messages is EPICS. We will discuss the architecture of the system, our experience with EPICS, and preliminary test results.

  8. The Prodiguer Messaging Platform

    NASA Astrophysics Data System (ADS)

    Denvil, S.; Greenslade, M. A.; Carenton, N.; Levavasseur, G.; Raciazek, J.

    2015-12-01

    CONVERGENCE is a French multi-partner national project designed to gather HPC and informatics expertise to innovate in the context of running French global climate models with differing grids and at differing resolutions. Efficient and reliable execution of these models and the management and dissemination of model output are some of the complexities that CONVERGENCE aims to resolve.At any one moment in time, researchers affiliated with the Institut Pierre Simon Laplace (IPSL) climate modeling group, are running hundreds of global climate simulations. These simulations execute upon a heterogeneous set of French High Performance Computing (HPC) environments. The IPSL's simulation execution runtime libIGCM (library for IPSL Global Climate Modeling group) has recently been enhanced so as to support hitherto impossible realtime use cases such as simulation monitoring, data publication, metrics collection, simulation control, visualizations … etc. At the core of this enhancement is Prodiguer: an AMQP (Advanced Message Queue Protocol) based event driven asynchronous distributed messaging platform. libIGCM now dispatches copious amounts of information, in the form of messages, to the platform for remote processing by Prodiguer software agents at IPSL servers in Paris. Such processing takes several forms: Persisting message content to database(s); Launching rollback jobs upon simulation failure; Notifying downstream applications; Automation of visualization pipelines; We will describe and/or demonstrate the platform's: Technical implementation; Inherent ease of scalability; Inherent adaptiveness in respect to supervising simulations; Web portal receiving simulation notifications in realtime.

  9. Evaluating Personalized Risk Messages.

    ERIC Educational Resources Information Center

    Weinstein, Neil D.; And Others

    1992-01-01

    An experiment with 766 homeowners compared 3 strategies for delivering radon test results to homeowners. Small improvements in consumer satisfaction were found for personalized messages (a telephone call or personal letter) over a form letter. No detectable improvement was found in recall of advice or compliance for any strategy. (SLD)

  10. Message in a Bottle

    ERIC Educational Resources Information Center

    Gallagher, Joy

    2008-01-01

    In this article, the author shares a lesson that uses the Message in a Bottle concept. This lesson combines social studies, language arts, technology, and art, particularly studying and drawing portraits and utilizing values within a drawing. As part of their grade-four art curriculum, students are required to correctly proportion the face and the…

  11. Listening and Message Interpretation

    ERIC Educational Resources Information Center

    Edwards, Renee

    2011-01-01

    Message interpretation, the notion that individuals assign meaning to stimuli, is related to listening presage, listening process, and listening product. As a central notion of communication, meaning includes (a) denotation and connotation, and (b) content and relational meanings, which can vary in ambiguity and vagueness. Past research on message…

  12. Are Instant Messages Speech?

    NASA Astrophysics Data System (ADS)

    Baron, Naomi S.

    Instant messaging (IM) is commonly viewed as a “spoken” medium, in light of its reputation for informality, non-standard spelling and punctuation, and use of lexical shortenings and emoticons. However, the actual nature of IM is an empirical issue that bears linguistic analysis.

  13. Research Messages 2011

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2012

    2012-01-01

    "Research messages 2011" is a collection of summaries of research projects published by National Centre for Vocational Education Research (NCVER) in 2011. The publication also has an overview essay that captures the themes and highlights from the research for the year, including: (1) the initial education and training of young people and their…

  14. Research Messages 2014

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2015

    2015-01-01

    "Research Messages 2014" is a collection of summaries of research published by the National Centre for Vocational Education Research (NCVER) in 2014 in the context of changing economic, industrial, social and education conditions, organised under the following broad categories: (1) Productivity: to sustain and build Australia's human…

  15. Grounding in Instant Messaging

    ERIC Educational Resources Information Center

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  16. Music's unspoken messages.

    PubMed

    Briggs, Tami

    2011-01-01

    Today, integrative medicine encompasses many healing arts therapies, including music. The universal language of music is simple, yet often forgotten, and communicates unspoken messages. The healing power of music in the health care setting creates a healing environment, distracts from pain, relaxes and de-stresses, and helps with sleep. PMID:22403857

  17. Research Messages 2010

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2011

    2011-01-01

    Research messages 2010 is a collection of summaries of research projects published by the National Centre for Vocational Education Research (NCVER). The summaries are clustered under five broad themes used by NCVER to organise its research and analysis: Industry and employers; Students and individuals; Teaching and learning: VET system; and VET in…

  18. Couriers in the Inca Empire: Getting Your Message Across. [Lesson Plan].

    ERIC Educational Resources Information Center

    2002

    This lesson shows how the Inca communicated across the vast stretches of their mountain realm, the largest empire of the pre-industrial world. The lesson explains how couriers carried messages along mountain-ridge roads, up and down stone steps, and over chasm-spanning footbridges. It states that couriers could pass a message from Quito (Ecuador)…

  19. Remote Asynchronous Message Service Gateway

    NASA Technical Reports Server (NTRS)

    Wang, Shin-Ywan; Burleigh, Scott C.

    2011-01-01

    The Remote Asynchronous Message Service (RAMS) gateway is a special-purpose AMS application node that enables exchange of AMS messages between nodes residing in different AMS "continua," notionally in different geographical locations. JPL s implementation of RAMS gateway functionality is integrated with the ION (Interplanetary Overlay Network) implementation of the DTN (Delay-Tolerant Networking) bundle protocol, and with JPL s implementation of AMS itself. RAMS protocol data units are encapsulated in ION bundles and are forwarded to the neighboring RAMS gateways identified in the source gateway s AMS management information base. Each RAMS gateway has interfaces in two communication environments: the AMS message space it serves, and the RAMS network - the grid or tree of mutually aware RAMS gateways - that enables AMS messages produced in one message space to be forwarded to other message spaces of the same venture. Each gateway opens persistent, private RAMS network communication channels to the RAMS gateways of other message spaces for the same venture, in other continua. The interconnected RAMS gateways use these communication channels to forward message petition assertions and cancellations among themselves. Each RAMS gateway subscribes locally to all subjects that are of interest in any of the linked message spaces. On receiving its copy of a message on any of these subjects, the RAMS gateway node uses the RAMS network to forward the message to every other RAMS gateway whose message space contains at least one node that has subscribed to messages on that subject. On receiving a message via the RAMS network from some other RAMS gateway, the RAMS gateway node forwards the message to all subscribers in its own message space.

  20. Passing and Catching in Rugby.

    ERIC Educational Resources Information Center

    Namudu, Mike M.

    This booklet contains the fundamentals for rugby at the primary school level. It deals primarily with passing and catching the ball. It contains instructions on (1) holding the ball for passing, (2) passing the ball to the left--standing, (3) passing the ball to the left--running, (4) making a switch pass, (5) the scrum half's normal pass, (6) the…

  1. Message based event specification for debugging nondeterministic parallel programs

    SciTech Connect

    Damohdaran-Kamal, S.K.; Francioni, J.M.

    1995-02-01

    Portability and reliability of parallel programs can be severely impaired by their nondeterministic behavior. Therefore, an effective means to precisely and accurately specify unacceptable nondeterministic behavior is necessary for testing and debugging parallel programs. In this paper we describe a class of expressions, called Message Expressions that can be used to specify nondeterministic behavior of message passing parallel programs. Specification of program behavior with Message Expressions is easier than pattern based specification techniques in that the former does not require knowledge of run-time event order, whereas that later depends on the user`s knowledge of the run-time event order for correct specification. We also discuss our adaptation of Message Expressions for use in a dynamic distributed testing and debugging tool, called mdb, for programs written for PVM (Parallel Virtual Machine).

  2. Sequoia Messaging Rate Benchmark

    SciTech Connect

    Friedley, Andrew

    2008-01-22

    The purpose of this benchmark is to measure the maximal message rate of a single compute node. The first num_cores ranks are expected to reside on the 'core' compute node for which message rate is being tested. After that, the next num_nbors ranks are neighbors for the first core rank, the next set of num_nbors ranks are neighbors for the second core rank, and so on. For example, testing an 8-core node (num_cores = 8) with 4 neighbors (num_nbors = 4) requires 8 + 8 * 4 - 40 ranks. The first 8 of those 40 ranks are expected to be on the 'core' node being benchmarked, while the rest of the ranks are on separate nodes.

  3. Sequoia Messaging Rate Benchmark

    Energy Science and Technology Software Center (ESTSC)

    2008-01-22

    The purpose of this benchmark is to measure the maximal message rate of a single compute node. The first num_cores ranks are expected to reside on the 'core' compute node for which message rate is being tested. After that, the next num_nbors ranks are neighbors for the first core rank, the next set of num_nbors ranks are neighbors for the second core rank, and so on. For example, testing an 8-core node (num_cores = 8)more » with 4 neighbors (num_nbors = 4) requires 8 + 8 * 4 - 40 ranks. The first 8 of those 40 ranks are expected to be on the 'core' node being benchmarked, while the rest of the ranks are on separate nodes.« less

  4. Extracting hidden messages in steganographic images

    DOE PAGESBeta

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residualsmore » contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.« less

  5. Extracting hidden messages in steganographic images

    SciTech Connect

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residuals contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.

  6. Secret Message Science Goggles

    ERIC Educational Resources Information Center

    DeVita, Christina; Ruppert, Sarah

    2007-01-01

    Light is radiation in wavelengths composed of many colors that are visible to the eyes. These wavelengths can be separated. One way to separate colors is with a filter. Filters keep certain wavelengths out and allow other wavelengths to pass through. In this article, the authors discuss an activity to provide students the opportunity to build a…

  7. Parallel S{sub n} Sweeps on Unstructured Grids: Algorithms for Prioritization, Grid Partitioning, and Cycle Detection

    SciTech Connect

    Plimpton, Steven J.; Hendrickson, Bruce; Burns, Shawn P.; McLendon, William III; Rauchwerger, Lawrence

    2005-07-15

    The method of discrete ordinates is commonly used to solve the Boltzmann transport equation. The solution in each ordinate direction is most efficiently computed by sweeping the radiation flux across the computational grid. For unstructured grids this poses many challenges, particularly when implemented on distributed-memory parallel machines where the grid geometry is spread across processors. We present several algorithms relevant to this approach: (a) an asynchronous message-passing algorithm that performs sweeps simultaneously in multiple ordinate directions, (b) a simple geometric heuristic to prioritize the computational tasks that a processor works on, (c) a partitioning algorithm that creates columnar-style decompositions for unstructured grids, and (d) an algorithm for detecting and eliminating cycles that sometimes exist in unstructured grids and can prevent sweeps from successfully completing. Algorithms (a) and (d) are fully parallel; algorithms (b) and (c) can be used in conjunction with (a) to achieve higher parallel efficiencies. We describe our message-passing implementations of these algorithms within a radiation transport package. Performance and scalability results are given for unstructured grids with up to 3 million elements (500 million unknowns) running on thousands of processors of Sandia National Laboratories' Intel Tflops machine and DEC-Alpha CPlant cluster.

  8. No Pass, No Drive?

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2001-01-01

    Discusses basis for Kentucky appellate court decision that state's no-pass, no-drive statute did not violate due-process and equal-protection clauses of the Kentucky and federal constitutions, but did violate the federal Family Education Rights and Privacy Act, but nevertheless did not invalidate the statute. Explains why the decision is…

  9. PASS and Reading Achievement.

    ERIC Educational Resources Information Center

    Kirby, John R.

    Two studies examined the effectiveness of the PASS (Planning, Attention, Simultaneous, and Successive cognitive processes) theory of intelligence in predicting reading achievement scores of normally achieving children and distinguishing children with reading disabilities from normally achieving children. The first study dealt with predicting…

  10. A Messaging Infrastructure for WLCG

    NASA Astrophysics Data System (ADS)

    Casey, James; Cons, Lionel; Lapka, Wojciech; Paladin, Massimo; Skaburskas, Konstantin

    2011-12-01

    During the EGEE-III project operational tools such as SAM, Nagios, Gridview, the regional Dashboard and GGUS moved to a communication architecture based on ActiveMQ, an open-source enterprise messaging solution. LHC experiments, in particular ATLAS, developed prototypes of systems using the same messaging infrastructure, validating the system for their use-cases. In this paper we describe the WLCG messaging use cases and outline an improved messaging architecture based on the experience gained during the EGEE-III period. We show how this provides a solid basis for many applications, including the grid middleware, to improve their resilience and reliability.

  11. Automatic Classification of E-Mail Messages by Message Type.

    ERIC Educational Resources Information Center

    May, Andrew D.

    1997-01-01

    Describes a system that automatically classifies e-mail messages in the HUMANIST electronic discussion group into one of four classes: question, response, announcement, or administrative. The system's ability to accurately classify a message was compared against manually assigned codes. Results suggested that there was a statistical agreement in…

  12. Modeling node bandwidth limits and their effects on vector combining algorithms

    SciTech Connect

    Littlefield, R.J.

    1992-01-13

    Each node in a message-passing multicomputer typically has several communication links. However, the maximum aggregate communication speed of a node is often less than the sum of its individual link speeds. Such computers are called node bandwidth limited (NBL). The NBL constraint is important when choosing algorithms because it can change the relative performance of different algorithms that accomplish the same task. This paper introduces a model of communication performance for NBL computers and uses the model to analyze the overall performance of three algorithms for vector combining (global sum) on the Intel Touchstone DELTA computer. Each of the three algorithms is found to be at least 33% faster than the other two for some combinations of machine size and vector length. The NBL constraint is shown to significantly affect the conditions under which each algorithm is fastest.

  13. Implementing the ICPD's message.

    PubMed

    Jain, A

    1995-01-01

    The International Conference on Population and Development held in Cairo in September 1994 recognized the need for reducing unwanted fertility and promoting smaller families within reproductive health services along with improving women's equality in education, health, and economic opportunity. The implementation of the main message would require an ideological transformation both for the population and for the development establishments. The implementation of a broadened population policy must incorporate the reduction of gender disparities as the primary goal. The problem is that the UNFPA has no influence over resources allocated to child health, female education, economic opportunities for women, or empowerment of women. Reproductive health and family planning programs should be integrated within the broader health services; however, reproductive health may not receive the desired high priority. Family planning programs are also expected to solve two problems: to improve individual well-being and to reduce overall fertility. Managers are likely to implement the reproductive health approach if it is a cost-effective way of reducing total fertility. However, no evidence exists to show that treating reproductive tract infections is a cost-effective way of reducing fertility. The primary objective of family planning programs should be empowerment of individuals to achieve their own reproductive goals in a healthful manner. Fertility reduction should be linked to fertility reduction by focusing on unwanted childbirth and to reproductive health services. The redesign of contraceptive services from a reproductive health perspective would deal with the contraindications of each method by developing standards for screening and focusing as well on the diagnosis and treatment of these conditions. The suggested role of the population sector in the tasks of development and family planning lies in promoting the main message to a wider national and international audience

  14. Modern Messaging for Distributed Sytems

    NASA Astrophysics Data System (ADS)

    Magnoni, L.

    2015-05-01

    Modern software applications rarely live in isolation and nowadays it is common practice to rely on services or consume information provided by remote entities. In such a distributed architecture, integration is key. Messaging, for more than a decade, is the reference solution to tackle challenges of a distributed nature, such as network unreliability, strong-coupling of producers and consumers and the heterogeneity of applications. Thanks to a strong community and a common effort towards standards and consolidation, message brokers are today the transport layer building blocks in many projects and services, both within the physics community and outside. Moreover, in recent years, a new generation of messaging services has appeared, with a focus on low-latency and high-performance use cases, pushing the boundaries of messaging applications. This paper will present messaging solutions for distributed applications going through an overview of the main concepts, technologies and services.

  15. Patient-Physician Web Messaging

    PubMed Central

    Liederman, Eric M; Lee, Jerry C; Baquero, Victor H; Seites, Paul G

    2005-01-01

    BACKGROUND Patients want electronic access to providers. Providers fear being overwhelmed by unreimbursed messages. OBJECTIVE Measure the effects of patient-physician web messaging on primary care practices. DESIGN/SETTING Retrospective analysis of 6 case and 9 control internal medicine (IM) and family practice (FP) physicians' message volume, and a survey of 5,971 patients' web messaging with 267 providers and staff in 16 community primary care clinics in the Sacramento, CA region. MEASUREMENTS AND MAIN RESULTS Case telephone volume was 18.2% lower (P =.002) and fell 6.50 times faster than control. Case total telephone plus web message volume was 13.7% lower (P =.025) and fell 5.84 times faster than control. Surveys were responded to by 40.3% (1,743/4,320) of patients and 61.4% (164/267) of providers and staff. Patients were overwhelmingly satisfied and providers and staff were generally satisfied; both found the system easy to use. Patient satisfaction correlated strongly with provider response time (Γ=0.557), and provider/staff satisfaction with computer skills (Γ=0.626) (Goodman-Kruskal Gamma [Γ] measure of ordinal association). CONCLUSIONS Secure web messaging improves on e-mail with encryption, access controls, message templates, customized message and prescription routing, knowledge content, and reimbursement. Further study is needed to determine whether reducing telephone traffic through the use of web messaging decreases provider interruptions and increases clinical efficiency during the workday. Satisfaction with web messaging may increase patient retention. PMID:15693928

  16. Improving scalability with loop transformations and message aggregation in parallel object-oriented frameworks for scientific computing

    SciTech Connect

    Bassetti, F.; Davis, K.; Quinlan, D.

    1998-09-01

    Application codes reliably achieve performance far less than the advertised capabilities of existing architectures, and this problem is worsening with increasingly-parallel machines. For large-scale numerical applications, stencil operations often impose the great part of the computational cost, and the primary sources of inefficiency are the costs of message passing and poor cache utilization. This paper proposes and demonstrates optimizations for stencil and stencil-like computations for both serial and parallel environments that ameliorate these sources of inefficiency. Achieving scalability, they believe, requires both algorithm design and compile-time support. The optimizations they present are automatable because the stencil-like computations are implemented at a high level of abstraction using object-oriented parallel array class libraries. These optimizations, which are beyond the capabilities of today compilers, may be performed automatically by a preprocessor such as the one they are currently developing.

  17. Priority nutrition messages.

    PubMed

    1991-01-01

    The Philippine Food and Nutrition Program deliver priority short, simple, clear, and action filled nutrition messages in different languages and dialects to different audiences. Its 1st priority task is to promote breast feeding. It informs mothers that breast milk is the most nutritious food for infants and that it protects them from infectious diseases. The program also encourages breast feeding as long as possible. If mothers cannot breast feed, they should talk to an infant nutrition expert to help them choose the best formula and learn about proper preparation. A 4-6 month infant needs to begin eating small amounts of semisolid nutritious foods. Moreover these foods must include body building foods, such as meat and eggs, and energy providing foods, such as corn and rice. Mothers must 1st attend to food needs of infants and preschoolers since they are more likely to suffer malnutrition than older children and adults. This is especially important when they suffer from an infection. Specifically, the very young need a variety of foods each day including the vitamin and mineral rich vegetables and fruits. In fact, families should grow their own fruits and vegetables to ensure an adequate supply. Hands must be cleaned with soap and water after defecation and before preparing foods. Mothers should add fats and oils when preparing foods because they provide concentrated energy, fatty acids, and fat soluble vitamins. Pregnant mothers must consume increased amounts of fish, beans, and other body building foods as well as regulating foods (vegetables and fruits). Mothers must also space births. They should weigh children each month to monitor nutritional levels. Moreover they must pay attention to signs indicating inadequate and insufficient food intake e.g., underweight and night blindness. PMID:12284666

  18. Congress passes space year

    NASA Astrophysics Data System (ADS)

    The year 1992 will mark the 500th anniversary of Christopher Columbus' arrival in America and the 35th anniversary of both the International Geophysical Year and the launch of Sputnik. The U.S. Senate passed a joint resolution (S.J.Res. 177) on November 21 recommending that the President endorse an International Space Year (ISY) in 1992. A similar resolution introduced in the House of Representatives was incorporated into the conference report (House Report 99-379) accompanying the authorization bill for the National Aeronautics and Space Administration (NASA) and approved by both houses, also on November 21. As Eos went to press, the NASA authorization bill (H.R. 1714) awaited President Ronald Reagan's signature.

  19. Education Bill passes

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    On March 2 the U.S. House of Representatives passed a bill authorizing $425 million for science and mathematics education in fiscal 1984; the authorization is $350 million more than President Ronald Reagan requested in his budget proposal (Eos, February 15, 1983, p. 65).H.R. 1310 allocates $295 million to the Department of Education not only to improve precollege instruction in science and math, but to beef up foreign language training to aid in improving international communication among scientists. The bill also allots $130 million to the National Science Foundation for a variety of programs, the lion's share of which aims to upgrade research equipment at colleges and universities. It is hoped that industry will match the $100 million targeted for this program.

  20. Broadcasting a message in a parallel computer

    DOEpatents

    Archer, Charles J; Faraj, Daniel A

    2014-11-18

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

  1. Broadcasting a message in a parallel computer

    DOEpatents

    Archer, Charles J; Faraj, Ahmad A

    2013-04-16

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

  2. Efficient implementation of Jacobi algorithms and Jacobi sets on distributed memory architectures

    SciTech Connect

    Eberlein, P.J. ); Park, H. )

    1990-04-01

    One-sided methods for implementing Jacobi diagonalization algorithms have been recently proposed for both distributed memory and vector machines. These methods are naturally well suited to distributed memory and vector architectures because of their inherent parallelism and their abundance of vector operations. Also, one-sided methods require substantially less message passing than the two-sided methods, and thus can achieve higher efficiency. The authors describe in detail the use of the one-sided Jacobi rotation as opposed to the rotation used in the Hestenes algorithm; they perceive the difference to have been widely misunderstood. Furthermore, the one-sided algorithm generalizes to other problems such as the nonsymmetric eigenvalue problem while the Hestenes algorithm does not. The authors discuss two new implementations for Jacobi sets for a ring connected array of processors and show their isomorphism to the round-robin ordering.

  3. Using Text Messages to Communicate with Patrons

    ERIC Educational Resources Information Center

    Konshak, Peter

    2009-01-01

    Text messaging is an ideal communications method for libraries, which often want to send short, concise messages to their patrons near and far. Uses for text messaging in libraries include reminders about items' due dates, hold pickup notices, program reminders, and even short messages of content. Some libraries are already using text messaging…

  4. Simultaneous message framing and error detection

    NASA Technical Reports Server (NTRS)

    Frey, A. H., Jr.

    1968-01-01

    Circuitry simultaneously inserts message framing information and detects noise errors in binary code data transmissions. Separate message groups are framed without requiring both framing bits and error-checking bits, and predetermined message sequence are separated from other message sequences without being hampered by intervening noise.

  5. Mission Services Evolution Center Message Bus

    NASA Technical Reports Server (NTRS)

    Mayorga, Arturo; Bristow, John O.; Butschky, Mike

    2011-01-01

    The Goddard Mission Services Evolution Center (GMSEC) Message Bus is a robust, lightweight, fault-tolerant middleware implementation that supports all messaging capabilities of the GMSEC API. This architecture is a distributed software system that routes messages based on message subject names and knowledge of the locations in the network of the interested software components.

  6. A parallel adaptive mesh refinement algorithm

    NASA Technical Reports Server (NTRS)

    Quirk, James J.; Hanebutte, Ulf R.

    1993-01-01

    Over recent years, Adaptive Mesh Refinement (AMR) algorithms which dynamically match the local resolution of the computational grid to the numerical solution being sought have emerged as powerful tools for solving problems that contain disparate length and time scales. In particular, several workers have demonstrated the effectiveness of employing an adaptive, block-structured hierarchical grid system for simulations of complex shock wave phenomena. Unfortunately, from the parallel algorithm developer's viewpoint, this class of scheme is quite involved; these schemes cannot be distilled down to a small kernel upon which various parallelizing strategies may be tested. However, because of their block-structured nature such schemes are inherently parallel, so all is not lost. In this paper we describe the method by which Quirk's AMR algorithm has been parallelized. This method is built upon just a few simple message passing routines and so it may be implemented across a broad class of MIMD machines. Moreover, the method of parallelization is such that the original serial code is left virtually intact, and so we are left with just a single product to support. The importance of this fact should not be underestimated given the size and complexity of the original algorithm.

  7. MessageSpace: a messaging system for health research

    NASA Astrophysics Data System (ADS)

    Escobar, Rodrigo D.; Akopian, David; Parra-Medina, Deborah; Esparza, Laura

    2013-03-01

    Mobile Health (mHealth) has emerged as a promising direction for delivery of healthcare services via mobile communication devices such as cell phones. Examples include texting-based interventions for chronic disease monitoring, diabetes management, control of hypertension, smoking cessation, monitoring medication adherence, appointment keeping and medical test result delivery; as well as improving patient-provider communication, health information communication, data collection and access to health records. While existing messaging systems very well support bulk messaging and some polling applications, they are not designed for data collection and processing of health research oriented studies. For that reason known studies based on text-messaging campaigns have been constrained in participant numbers. In order to empower healthcare promotion and education research, this paper presents a system dedicated for healthcare research. It is designed for convenient communication with various study groups, feedback collection and automated processing.

  8. Reactions to threatening health messages

    PubMed Central

    2012-01-01

    Background Threatening health messages that focus on severity are popular, but frequently have no effect or even a counterproductive effect on behavior change. This paradox (i.e. wide application despite low effectiveness) may be partly explained by the intuitive appeal of threatening communication: it may be hard to predict the defensive reactions occurring in response to fear appeals. We examine this hypothesis by using two studies by Brown and colleagues, which provide evidence that threatening health messages in the form of distressing imagery in anti-smoking and anti-alcohol campaigns cause defensive reactions. Methods We simulated both Brown et al. experiments, asking participants to estimate the reactions of the original study subjects to the threatening health information (n = 93). Afterwards, we presented the actual original study outcomes. One week later, we assessed whether this knowledge of the actual study outcomes helped participants to more successfully estimate the effectiveness of the threatening health information (n = 72). Results Results showed that participants were initially convinced of the effectiveness of threatening health messages and were unable to anticipate the defensive reactions that in fact occurred. Furthermore, these estimates did not improve after participants had been explained the dynamics of threatening communication as well as what the effects of the threatening communication had been in reality. Conclusions These findings are consistent with the hypothesis that the effectiveness of threatening health messages is intuitively appealing. What is more, providing empirical evidence against the use of threatening health messages has very little effect on this intuitive appeal. PMID:23171445

  9. Data communications for a collective operation in a parallel active messaging interface of a parallel computer

    SciTech Connect

    Faraj, Daniel A.

    2015-11-19

    Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and bit masks; receiving in an origin endpoint of the PAMI a collective instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint; constructing a bit mask for the received collective instruction; selecting, from among the associated algorithms and bit masks, a data communications algorithm in dependence upon the constructed bit mask; and executing the collective instruction, transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

  10. Data communications for a collective operation in a parallel active messaging interface of a parallel computer

    DOEpatents

    Faraj, Daniel A

    2013-07-16

    Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and bit masks; receiving in an origin endpoint of the PAMI a collective instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint; constructing a bit mask for the received collective instruction; selecting, from among the associated algorithms and bit masks, a data communications algorithm in dependence upon the constructed bit mask; and executing the collective instruction, transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

  11. Distributed-Memory Computing With the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA)

    NASA Technical Reports Server (NTRS)

    Riley, Christopher J.; Cheatwood, F. McNeil

    1997-01-01

    The Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA), a Navier-Stokes solver, has been modified for use in a parallel, distributed-memory environment using the Message-Passing Interface (MPI) standard. A standard domain decomposition strategy is used in which the computational domain is divided into subdomains with each subdomain assigned to a processor. Performance is examined on dedicated parallel machines and a network of desktop workstations. The effect of domain decomposition and frequency of boundary updates on performance and convergence is also examined for several realistic configurations and conditions typical of large-scale computational fluid dynamic analysis.

  12. Scheduling real-time messages in combat vehicle LANs

    NASA Astrophysics Data System (ADS)

    Richardson, Paul; Sarkar, Susanta P.

    1999-07-01

    The emergence of LAN architectures in Combat Vehicle computer system is part of an emerging new class of LAN systems. These systems operate in harsh, non-deterministic environments, and are expected to sustain faults and continue operating. The computer system perform dual functions of system control and real-time information exchange. The LANs in these systems have a hybrid message set consisting of vehicle control messages with crisply defined time constraints and real-time information with vaguely defined time constraints. Among platforms of this type, we find combat vehicles of all types, systems involved in the clean up of hazardous materials, space vehicles, and special anti-terrorist vehicles. We present the Adaptive Earliest Deadline First (AEDF) scheduling algorithm and a benefit metric for measuring performance. The AEDF scheduler was developed for the message sets found in combat vehicle LANs. This scheduler guarantees 100 percent of message time constraints under nominal conditions and optimizes scheduling under overload conditions induced by faults. The benefit metric provides an accurate means of evaluating scheduler performance based on message importance, timeliness and state.

  13. The mushroom message.

    PubMed

    Zimmerman, M

    1992-04-28

    A basic law of ecology is that living things are tightly dependent on one another, often in ways that are not easy to imagine. Who, for example, would have predicted that when the last dodo was killed in 1675, that death would lead to the slow extermination of the tambalocoque tree, whose fruits germinate only after passing through the dodo's digestive system? Now no natural strands of tambalocoque younger than 300 years can be found. Or who would have predicted that clear-cutting tropical rainforests would so significantly alter local weather patterns that the tropical rainforest biome itself and its vast diversity of life might not survive? Such interactions are worth noting because of the possible ramifications of a phenomenon that ecologists have just begun to document. Mushrooms worldwide appear to be in a catastrophic state of decline. Throughout Europe, in countries with terrains as diverse as Holland, Germany, Austria, Czechoslovakia, Poland and England, wild mushrooms are becoming increasingly difficult to find. Those fungi that are found are significantly smaller than those found years ago. Preliminary data suggest that the same troubling situation is occurring throughout North American as well. The decline has been so precipitous that biologists have begun to refer to it as a mass extinction. The 2 obvious explanations for the demise of the mushrooms--habitat destruction and overpicking of edible types by an ever growing human population--have been ruled out. Sophisticated sampling schemes designed by ecologists control for the fact that there is less land available for wild mushrooms; they have been declining at a rate that far exceeds the rate at which land is being developed. The fact that the decline has affected both edible and inedible mushrooms equally indicates that humans hunting for tasty treats are not the main cause of the problem. The loss of wild mushrooms worldwide might not seem like that big a deal, but the consequences may well be grave

  14. Sarsat location algorithms

    NASA Astrophysics Data System (ADS)

    Nardi, Jerry

    The Satellite Aided Search and Rescue (Sarsat) is designed to detect and locate distress beacons using satellite receivers. Algorithms used for calculating the positions of 406 MHz beacons and 121.5/243 MHz beacons are presented. The techniques for matching, resolving and averaging calculated locations from multiple satellite passes are also described along with results pertaining to single pass and multiple pass location estimate accuracy.

  15. Fast parallel algorithms for short-range molecular dynamics

    SciTech Connect

    Plimpton, S.

    1993-05-01

    Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a subset of atoms; the second assigns each a subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently -- those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 10,000,000 atoms on three parallel supercomputers, the nCUBE 2, Intel iPSC/860, and Intel Delta. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and the Intel Delta performs about 30 times faster than a single Y-MP processor and 12 times faster than a single C90 processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

  16. EDITORIAL: Message from the Editor

    NASA Astrophysics Data System (ADS)

    Thomas, Paul

    2009-01-01

    The end of 2008 cannot pass without remarking that the economic news has repeatedly strengthened the case for nuclear fusion; not perhaps to solve the immediate crises but to offer long-term security of energy supply. Although temporary, the passage of the price of oil through 100 per barrel is a portent of things to come and should bolster our collective determination to develop nuclear fusion into a viable energy source. It is with great pride, therefore, that I can highlight the contributions that the Nuclear Fusion journal has made to the research programme and the consolidation of its position as the lead journal in the field. Of course, the journal would be nothing without its authors and referees and I would like to pass on my sincere thanks to them all for their work in 2008 and look forward to a continuing, successful collaboration in 2009. Refereeing The Nuclear Fusion Editorial Office understands how much effort is required of our referees. The Editorial Board decided that an expression of thanks to our most loyal referees is appropriate and so, since January 2005, we have been offering the top ten most loyal referees over the past year a personal subscription to Nuclear Fusion with electronic access for one year, free of charge. To select the top referees we have adopted the criterion that a researcher should have acted as a referee or adjudicator for at least two different manuscripts during the period from November 2007 to November 2008 and provided particularly detailed advice to the authors. We have excluded our Board members and those referees who were already listed in the last four years. According to our records the following people met this criterion. Congratulations and many, many thanks! T. Hino (Hokkaido University, Japan) M. Sugihara (ITER Cadarache, France) M. Dreval (Saskatchewan University, Canada) M. Fenstermacher (General Atomics, USA) V.S. Marchenko (Institute for Nuclear Research, Ukraine) G.V. Pereverzev (Max-Planck-Institut fuer

  17. Modularity, reuse and efficiency with message-driven libraries

    SciTech Connect

    Kale, L.V.; Gursoy, A.

    1995-12-01

    Software re-use via libraries is a strategy that allows the cost of software to be amortized. A parallel programming system must support the ability to develop modules that can be {open_quotes}fitted together{close_quotes} in a variety of contexts. Although it is important to be able to reuse parallel libraries, it is also more difficult to use parallel modules in comparison to sequential module. We present a methodology for developing libraries that addresses these issues effectively. The methodology, which is embodied in the Charm system, employs message-driven execution (in contrast to traditional, receive based message passing), information sharing abstractions, the notion of branched objects, and explicit support for modules.

  18. Multiple pass laser amplifier system

    DOEpatents

    Brueckner, Keith A.; Jorna, Siebe; Moncur, N. Kent

    1977-01-01

    A laser amplification method for increasing the energy extraction efficiency from laser amplifiers while reducing the energy flux that passes through a flux limited system which includes apparatus for decomposing a linearly polarized light beam into multiple components, passing the components through an amplifier in delayed time sequence and recombining the amplified components into an in phase linearly polarized beam.

  19. Re: Design Changing the Message

    ERIC Educational Resources Information Center

    Wall, Miranda Wakeman

    2008-01-01

    The advertisements that flood everyone's visual culture are designed to create desire. From the author's experience, most high school students are not aware of the messages that they are bombarded with every day, and if they are, few care or think about them critically. The author's goals for this lesson were to increase students' awareness of the…

  20. Radiating Messages: An International Perspective.

    ERIC Educational Resources Information Center

    Walker, Janet

    2003-01-01

    Negative messages about the detrimental impacts of divorce on children prompted urgent calls in the United Kingdom for a reinstatement of traditional family values. Suggests that although the effects of divorce are real, care should be taken to avoid exaggeration, thus moving the debate to one centered on providing better support, advice, and…

  1. The Media and the Message.

    ERIC Educational Resources Information Center

    Cook, Glenn

    2001-01-01

    The experiences of Columbine and El Cajon high schools with media onslaughts following traumatic shooting incidents underscore the importance of getting the message across and sticking to known facts. In a crisis, speculation can hurt everyone. The most important elements in crisis communications are planning and media relations. (MLH)

  2. Instant Messaging: IM Online! RU?

    ERIC Educational Resources Information Center

    Farmer, Robert

    2005-01-01

    This article discusses the technology of instant messaging (IM), a relatively simple form of communication. It is also--by its very nature--a collaborative communications tool. This collaborative nature is what makes IM ideal for educational and learning environments. With IM playing such a large role in the communication, interactivity, and…

  3. Messages from the Abyss

    NASA Astrophysics Data System (ADS)

    2003-10-01

    . Never before had anybody witnessed the last "scream" from matter in the deadly grip of a black hole, about to pass the point of no return towards an unknown fate. At the border ESO PR Photo 29b/03 ESO PR Photo 29b/03 [Preview - JPEG: 400 x 516 pix - 87k [Normal - JPEG: 800 x 1032 pix - 219k] Captions : PR Photo 29b/03 displays the "light curve" of a light flare from the galactic centre, as observed in the K-band (wavelength 2.2 µm) on June 16, 2003. This and a second flare discovered about 24 hours earlier show variability on a time scale of a few minutes and appear to show larger variations (arrows) with a 17-minute periodicity. The rapid variability implies that the infrared emission comes from just outside (the event horizon of) the black hole. If the periodicity is a fundamental property of the motion of gas orbiting the black hole, the Galactic Centre black hole must rotate with about half the maximum spin rate allowed by General Relativity. The present observations thus probe the space-time structure in the immediate vicinity of that event horizon. A careful analysis of the new observational data, reported in this week's issue of the Nature magazine, has revealed that the infrared emission originates from within a few thousandths of an arcsecond [4] from the position of the black hole (corresponding to a distance of a few light-hours) and that it varies on time scales of minutes ( PR Photo 29b/03 ). This proves that the infrared signals must come from just outside the so-called "event horizon" of the black hole, that is the "surface of no return" from which even light cannot escape. The rapid variability seen in all data obtained by the VLT clearly indicates that the region around this horizon must have chaotic properties - very much like those seen in thunderstorms or solar flares [5]. " Our data give us unprecedented information about what happens just outside the event horizon and let us test the predictions of General Relativity " explains Daniel Rouan , a

  4. Split-C and active messages under SUNMOS on the Intel Paragon

    SciTech Connect

    Reisen, R.; Maccabe, A.B.

    1994-04-01

    The compute power of the individual nodes of massively parallel systems increases steadily, while network latencies and bandwidth have not improved as quickly. Many researches believe that it is necessary to use explicit message passing in order to get the best possible performance out of these systems. High level parallel languages are shunned out of fear they might compromise performance. In this paper we have a look at one such language called Split-C. It fits into a middle ground between efforts such as High Performance Fortran (HPF) and explicit message passing. HPF tries to hide the underlying architecture from the programmer and let the compiler and the run time system make decision about parallelization, location of data, and the mechanisms used to transfer the data from one node to another. On the other hand, explicit message passing leaves all the decision to the programmer. Split-C allows access to a global address space, but leaves the programmer in control of the location of data, and offers a clear cost model for data access. Split-C is based on Active Messages. We have implemented both under the SUNMOS operating system on the Intel Paragon. We will discuss performance issues of Split-C and make direct comparisons to the Thinking Machines CM-5 implementation. We will also scrutinize Active Messages, discuss their properties and drawbacks, and show that other mechanisms can be used to support Split-C.

  5. Representing culture in interstellar messages

    NASA Astrophysics Data System (ADS)

    Vakoch, Douglas A.

    2008-09-01

    As scholars involved with the Search for Extraterrestrial Intelligence (SETI) have contemplated how we might portray humankind in any messages sent to civilizations beyond Earth, one of the challenges they face is adequately representing the diversity of human cultures. For example, in a 2003 workshop in Paris sponsored by the SETI Institute, the International Academy of Astronautics (IAA) SETI Permanent Study Group, the International Society for the Arts, Sciences and Technology (ISAST), and the John Templeton Foundation, a varied group of artists, scientists, and scholars from the humanities considered how to encode notions of altruism in interstellar messages . Though the group represented 10 countries, most were from Europe and North America, leading to the group's recommendation that subsequent discussions on the topic should include more globally representative perspectives. As a result, the IAA Study Group on Interstellar Message Construction and the SETI Institute sponsored a follow-up workshop in Santa Fe, New Mexico, USA in February 2005. The Santa Fe workshop brought together scholars from a range of disciplines including anthropology, archaeology, chemistry, communication science, philosophy, and psychology. Participants included scholars familiar with interstellar message design as well as specialists in cross-cultural research who had participated in the Symposium on Altruism in Cross-cultural Perspective, held just prior to the workshop during the annual conference of the Society for Cross-cultural Research . The workshop included discussion of how cultural understandings of altruism can complement and critique the more biologically based models of altruism proposed for interstellar messages at the 2003 Paris workshop. This paper, written by the chair of both the Paris and Santa Fe workshops, will explore the challenges of communicating concepts of altruism that draw on both biological

  6. Txt2MEDLINE: text-messaging access to MEDLINE/PubMed.

    PubMed

    Fontelo, Paul; Liu, Fang; Muin, Michael; Tolentino, Herman; Ackerman, Michael

    2006-01-01

    We developed a text messaging system for processing incoming Short Message Service (SMS) queries, retrieving medical journal citations from MEDLINE/PubMed and sending them back to the user in the text message format. A database of medical terminology abbreviations and acronyms was developed to reduce the size of text in journal citations and abstracts because of the 160-character per message limit of text messages. Queries may be sent as full-length terms or abbreviations. An algorithm transforms the citations into the SMS format. An abbreviated TBL (the bottom-line) summary instead of the full abstract is sent to the mobile device to shorten the resulting text. The system decreases citation size by 77.5+/-7.9%. Txt2MEDLINE provides physicians and healthcare personnel another rapid and convenient method for searching MEDLINE/PubMed through wireless mobile devices. It is accessible from any location worldwide where GSM wireless service is available. PMID:17238343

  7. Toward Predicting Popularity of Social Marketing Messages

    NASA Astrophysics Data System (ADS)

    Yu, Bei; Chen, Miao; Kwok, Linchi

    Popularity of social marketing messages indicates the effectiveness of the corresponding marketing strategies. This research aims to discover the characteristics of social marketing messages that contribute to different level of popularity. Using messages posted by a sample of restaurants on Facebook as a case study, we measured the message popularity by the number of "likes" voted by fans, and examined the relationship between the message popularity and two properties of the messages: (1) content, and (2) media type. Combining a number of text mining and statistics methods, we have discovered some interesting patterns correlated to "more popular" and "less popular" social marketing messages. This work lays foundation for building computational models to predict the popularity of social marketing messages in the future.

  8. Presentation of dynamically overlapping auditory messages in user interfaces

    SciTech Connect

    Papp, A.L.

    1997-09-01

    This dissertation describes a methodology and example implementation for the dynamic regulation of temporally overlapping auditory messages in computer-user interfaces. The regulation mechanism exists to schedule numerous overlapping auditory messages in such a way that each individual message remains perceptually distinct from all others. The method is based on the research conducted in the area of auditory scene analysis. While numerous applications have been engineered to present the user with temporally overlapped auditory output, they have generally been designed without any structured method of controlling the perceptual aspects of the sound. The method of scheduling temporally overlapping sounds has been extended to function in an environment where numerous applications can present sound independently of each other. The Centralized Audio Presentation System is a global regulation mechanism that controls all audio output requests made from all currently running applications. The notion of multimodal objects is explored in this system as well. Each audio request that represents a particular message can include numerous auditory representations, such as musical motives and voice. The Presentation System scheduling algorithm selects the best representation according to the current global auditory system state, and presents it to the user within the request constraints of priority and maximum acceptable latency. The perceptual conflicts between temporally overlapping audio messages are examined in depth through the Computational Auditory Scene Synthesizer. At the heart of this system is a heuristic-based auditory scene synthesis scheduling method. Different schedules of overlapped sounds are evaluated and assigned penalty scores. High scores represent presentations that include perceptual conflicts between over-lapping sounds. Low scores indicate fewer and less serious conflicts. A user study was conducted to validate that the perceptual difficulties predicted by

  9. A public-key cryptosystem for quantum message transmission

    NASA Astrophysics Data System (ADS)

    Yang, Li

    2005-01-01

    We present a quantum public-key cryptography protocol for quantum message transmission. The private key of this protocol includes three classical matrices: a generator matrix of a Goppa code, an invertible matrix and a permutation matrix. The public key is product of these three matrices. The encryption and decryption algorithms are merely quantum computations related with the transformations between bases of the quantum registers. The security of this protocol is based on the hypothesis that there is no effective algorithm of NP-complete problem.

  10. Race Socialization Messages across Historical Time

    ERIC Educational Resources Information Center

    Brown, Tony N.; Lesane-Brown, Chase L.

    2006-01-01

    In this study we investigated whether the content of race socialization messages varied by birth cohort, using data from a national probability sample. Most respondents recalled receiving messages about what it means to be black from their parents or guardians; these messages were coded into five mutually exclusive content categories: individual…

  11. 78 FR 64202 - Quantitative Messaging Research

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-28

    ... COMMISSION Quantitative Messaging Research AGENCY: Commodity Futures Trading Commission. ACTION: Notice... message testing research (for which CFTC received fast- track OMB approval) and is necessary to identify... comments using only one method and identify that it is for the ``Quantitative Messaging Research.''...

  12. 47 CFR 10.420 - Message elements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Message elements. 10.420 Section 10.420... § 10.420 Message elements. A WEA Alert Message processed by a Participating CMS Provider shall include five mandatory CAP elements—Event Type; Area Affected; Recommended Action; Expiration Time (with...

  13. 47 CFR 10.420 - Message elements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Message elements. 10.420 Section 10.420... § 10.420 Message elements. A WEA Alert Message processed by a Participating CMS Provider shall include five mandatory CAP elements—Event Type; Area Affected; Recommended Action; Expiration Time (with...

  14. 47 CFR 10.420 - Message elements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Message elements. 10.420 Section 10.420... Requirements § 10.420 Message elements. A CMAS Alert Message processed by a Participating CMS Provider shall include five mandatory CAP elements—Event Type; Area Affected; Recommended Action; Expiration Time...

  15. 47 CFR 10.420 - Message elements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Message elements. 10.420 Section 10.420... Requirements § 10.420 Message elements. A CMAS Alert Message processed by a Participating CMS Provider shall include five mandatory CAP elements—Event Type; Area Affected; Recommended Action; Expiration Time...

  16. 47 CFR 10.420 - Message elements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Message elements. 10.420 Section 10.420... Requirements § 10.420 Message elements. A CMAS Alert Message processed by a Participating CMS Provider shall include five mandatory CAP elements—Event Type; Area Affected; Recommended Action; Expiration Time...

  17. Security message exchange interoperability scenarios

    SciTech Connect

    Tarman, Thomas

    1998-07-01

    This contribution describes three interoperability scenarios for the ATM Security Message Exchange (SME) protocol. These scenarios include network-wide signaling support for the Security Services Information Element, partial signaling support wherethe SSIE is only supported in private or workgroup ATM networks, and the case where the SSIE is nonsupported by any network elements (exceptthosethat implement security services). Explanatory text is proposed for inclusion infection 2.3 of the ATM Security Specification, Version 1.0.

  18. Instant Messaging in Dental Education.

    PubMed

    Khatoon, Binish; Hill, Kirsty B; Walmsley, A Damien

    2015-12-01

    Instant messaging (IM) is when users communicate instantly via their mobile devices, and it has become one of the most preferred choices of tools to communicate amongst health professions students. The aim of this study was to understand how dental students communicate via IM, faculty members' perspectives on using IM to communicate with students, and whether such tools are useful in the learning environment. After free-associating themes on online communication, two draft topic guides for structured interviews were designed that focussed on mobile device-related communication activities. A total of 20 students and six faculty members at the University of Birmingham School of Dentistry agreed to take part in the interviews. Students were selected from years 1-5 representing each year group. The most preferred communication tools were emails, social networking, and IM. Emails were used for more formal messages, and IM and social networking sites were used for shorter messages. WhatsApp was the most used IM app because of its popular features such as being able to check if recipients have read and received messages and group work. The students reported that changes were necessary to improve their communication with faculty members. The faculty members reported having mixed feelings toward the use of IM to communicate with students. The students wished to make such tools a permanent part of their learning environment, but only with the approval of faculty members. The faculty members were willing to accept IM as a communication tool only if it is monitored and maintained by the university and has a positive effect on learning. PMID:26632303

  19. Preparing EBS messages. [Emergency Broadcast System (EBS)

    SciTech Connect

    Vogt, B.M., Sorensen, J.H.

    1992-09-01

    Warning messages transmitted to populations at risk from an accidental release of chemical agent must be carefully designed to maximize appropriate responses from affected publics. This guide develops an approach for preparing Emergency Broadcast System (EBS) messages for the Chemical Stockpile Emergency Preparedness Program (CSEPP). Sample messages illustrate the application of this approach. While the sample messages do not cover every emergency situation, the texts are generic in that accident and location specific factors can be incorporated into the final message developed by local emergency planners. Thus they provide a starting point, not an end product, for emergency planners.

  20. Nonblocking and orphan free message logging protocols

    NASA Technical Reports Server (NTRS)

    Alvisi, Lorenzo; Hoppe, Bruce; Marzullo, Keith

    1992-01-01

    Currently existing message logging protocols demonstrate a classic pessimistic vs. optimistic tradeoff. We show that the optimistic-pessimistic tradeoff is not inherent to the problem of message logging. We construct a message-logging protocol that has the positive features of both optimistic and pessimistic protocol: our protocol prevents orphans and allows simple failure recovery; however, it requires no blocking in failure-free runs. Furthermore, this protocol does not introduce any additional message overhead as compared to one implemented for a system in which messages may be lost but processes do not crash.

  1. Distributed parallel messaging for multiprocessor systems

    DOEpatents

    Chen, Dong; Heidelberger, Philip; Salapura, Valentina; Senger, Robert M; Steinmacher-Burrow, Burhard; Sugawara, Yutaka

    2013-06-04

    A method and apparatus for distributed parallel messaging in a parallel computing system. The apparatus includes, at each node of a multiprocessor network, multiple injection messaging engine units and reception messaging engine units, each implementing a DMA engine and each supporting both multiple packet injection into and multiple reception from a network, in parallel. The reception side of the messaging unit (MU) includes a switch interface enabling writing of data of a packet received from the network to the memory system. The transmission side of the messaging unit, includes switch interface for reading from the memory system when injecting packets into the network.

  2. A Decompositional Approach to Executing Quality Data Model Algorithms on the i2b2 Platform.

    PubMed

    Mo, Huan; Jiang, Guoqian; Pacheco, Jennifer A; Kiefer, Richard; Rasmussen, Luke V; Pathak, Jyotishman; Denny, Joshua C; Thompson, William K

    2016-01-01

    The Quality Data Model (QDM) is an established standard for representing electronic clinical quality measures on electronic health record (EHR) repositories. The Informatics for Integrated Biology and the Bedside (i2b2) is a widely used platform for implementing clinical data repositories. However, translation from QDM to i2b2 is challenging, since QDM allows for complex queries beyond the capability of single i2b2 messages. We have developed an approach to decompose complex QDM algorithms into workflows of single i2b2 messages, and execute them on the KNIME data analytics platform. Each workflow operation module is composed of parameter lists, a template for the i2b2 message, an mechanism to create parameter updates, and a web service call to i2b2. The communication between workflow modules relies on passing keys ofi2b2 result sets. As a demonstration of validity, we describe the implementation and execution of a type 2 diabetes mellitus phenotype algorithm against an i2b2 data repository. PMID:27570665

  3. A Decompositional Approach to Executing Quality Data Model Algorithms on the i2b2 Platform

    PubMed Central

    Mo, Huan; Jiang, Guoqian; Pacheco, Jennifer A.; Kiefer, Richard; Rasmussen, Luke V.; Pathak, Jyotishman; Denny, Joshua C.; Thompson, William K.

    2016-01-01

    The Quality Data Model (QDM) is an established standard for representing electronic clinical quality measures on electronic health record (EHR) repositories. The Informatics for Integrated Biology and the Bedside (i2b2) is a widely used platform for implementing clinical data repositories. However, translation from QDM to i2b2 is challenging, since QDM allows for complex queries beyond the capability of single i2b2 messages. We have developed an approach to decompose complex QDM algorithms into workflows of single i2b2 messages, and execute them on the KNIME data analytics platform. Each workflow operation module is composed of parameter lists, a template for the i2b2 message, an mechanism to create parameter updates, and a web service call to i2b2. The communication between workflow modules relies on passing keys ofi2b2 result sets. As a demonstration of validity, we describe the implementation and execution of a type 2 diabetes mellitus phenotype algorithm against an i2b2 data repository. PMID:27570665

  4. Asynchronous Message Service Reference Implementation

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.

    2011-01-01

    This software provides a library of middleware functions with a simple application programming interface, enabling implementation of distributed applications in conformance with the CCSDS AMS (Consultative Committee for Space Data Systems Asynchronous Message Service) specification. The AMS service, and its protocols, implement an architectural concept under which the modules of mission systems may be designed as if they were to operate in isolation, each one producing and consuming mission information without explicit awareness of which other modules are currently operating. Communication relationships among such modules are self-configuring; this tends to minimize complexity in the development and operations of modular data systems. A system built on this model is a society of generally autonomous, inter-operating modules that may fluctuate freely over time in response to changing mission objectives, modules functional upgrades, and recovery from individual module failure. The purpose of AMS, then, is to reduce mission cost and risk by providing standard, reusable infrastructure for the exchange of information among data system modules in a manner that is simple to use, highly automated, flexible, robust, scalable, and efficient. The implementation is designed to spawn multiple threads of AMS functionality under the control of an AMS application program. These threads enable all members of an AMS-based, distributed application to discover one another in real time, subscribe to messages on specific topics, and to publish messages on specific topics. The query/reply (client/server) communication model is also supported. Message exchange is optionally subject to encryption (to support confidentiality) and authorization. Fault tolerance measures in the discovery protocol minimize the likelihood of overall application failure due to any single operational error anywhere in the system. The multi-threaded design simplifies processing while enabling application nodes to

  5. A reduced-complexity data-fusion algorithm using belief propagation for location tracking in heterogeneous observations.

    PubMed

    Chiou, Yih-Shyh; Tsai, Fuan

    2014-06-01

    This paper presents a low-complexity and high-accuracy algorithm to reduce the computational load of the traditional data-fusion algorithm with heterogeneous observations for location tracking. For the location-estimation technique with the data fusion of radio-based ranging measurement and speed-based sensing measurement, the proposed tracking scheme, based on the Bayesian filtering concept, is handled by a state space model. The location tracking problem is divided into many mutual-interaction local constraints with the inherent message- passing features of factor graphs. During each iteration cycle, the messages with reliable information are passed efficiently between the prediction phase and the correction phase to simplify the data-fusion implementation for tracking the location of the mobile terminal. Numerical simulations show that the proposed forward and one-step backward refining tracking approach that combines radio ranging with speed sensing measurements for data fusion not only can achieve an accurate location close to that of the traditional Kalman filtering data-fusion algorithm, but also has much lower computational complexity. PMID:24013831

  6. Run-time scheduling and execution of loops on message passing machines

    NASA Technical Reports Server (NTRS)

    Crowley, Kay; Saltz, Joel; Mirchandaney, Ravi; Berryman, Harry

    1989-01-01

    Sparse system solvers and general purpose codes for solving partial differential equations are examples of the many types of problems whose irregularity can result in poor performance on distributed memory machines. Often, the data structures used in these problems are very flexible. Crucial details concerning loop dependences are encoded in these structures rather than being explicitly represented in the program. Good methods for parallelizing and partitioning these types of problems require assignment of computations in rather arbitrary ways. Naive implementations of programs on distributed memory machines requiring general loop partitions can be extremely inefficient. Instead, the scheduling mechanism needs to capture the data reference patterns of the loops in order to partition the problem. First, the indices assigned to each processor must be locally numbered. Next, it is necessary to precompute what information is needed by each processor at various points in the computation. The precomputed information is then used to generate an execution template designed to carry out the computation, communication, and partitioning of data, in an optimized manner. The design is presented for a general preprocessor and schedule executer, the structures of which do not vary, even though the details of the computation and of the type of information are problem dependent.

  7. Run-time scheduling and execution of loops on message passing machines

    NASA Technical Reports Server (NTRS)

    Saltz, Joel; Crowley, Kathleen; Mirchandaney, Ravi; Berryman, Harry

    1990-01-01

    Sparse system solvers and general purpose codes for solving partial differential equations are examples of the many types of problems whose irregularity can result in poor performance on distributed memory machines. Often, the data structures used in these problems are very flexible. Crucial details concerning loop dependences are encoded in these structures rather than being explicitly represented in the program. Good methods for parallelizing and partitioning these types of problems require assignment of computations in rather arbitrary ways. Naive implementations of programs on distributed memory machines requiring general loop partitions can be extremely inefficient. Instead, the scheduling mechanism needs to capture the data reference patterns of the loops in order to partition the problem. First, the indices assigned to each processor must be locally numbered. Next, it is necessary to precompute what information is needed by each processor at various points in the computation. The precomputed information is then used to generate an execution template designed to carry out the computation, communication, and partitioning of data, in an optimized manner. The design is presented for a general preprocessor and schedule executer, the structures of which do not vary, even though the details of the computation and of the type of information are problem dependent.

  8. Static analysis techniques for semiautomatic synthesis of message passing software skeletons

    SciTech Connect

    Sottile, Matthew; Dagit, Jason; Zhang, Deli; Hendry, Gilbert; Dechev, Damian

    2015-06-29

    The design of high-performance computing architectures demands performance analysis of large-scale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this article is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed for the purposes of the skeleton. In this work, we develop a semiautomatic approach for extracting program skeletons based on compiler program analysis. Finally, we demonstrate correctness of our skeleton extraction process by comparing details from communication traces, as well as show the performance speedup of using skeletons by running simulations in the SST/macro simulator.

  9. Static analysis techniques for semiautomatic synthesis of message passing software skeletons

    DOE PAGESBeta

    Sottile, Matthew; Dagit, Jason; Zhang, Deli; Hendry, Gilbert; Dechev, Damian

    2015-06-29

    The design of high-performance computing architectures demands performance analysis of large-scale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this article is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed formore » the purposes of the skeleton. In this work, we develop a semiautomatic approach for extracting program skeletons based on compiler program analysis. Finally, we demonstrate correctness of our skeleton extraction process by comparing details from communication traces, as well as show the performance speedup of using skeletons by running simulations in the SST/macro simulator.« less

  10. rMPI : increasing fault resiliency in a message-passing environment.

    SciTech Connect

    Stearley, Jon R.; Laros, James H., III; Ferreira, Kurt Brian; Pedretti, Kevin Thomas Tauke; Oldfield, Ron A.; Riesen, Rolf; Brightwell, Ronald Brian

    2011-04-01

    As High-End Computing machines continue to grow in size, issues such as fault tolerance and reliability limit application scalability. Current techniques to ensure progress across faults, like checkpoint-restart, are unsuitable at these scale due to excessive overheads predicted to more than double an applications time to solution. Redundant computation, long used in distributed and mission critical systems, has been suggested as an alternative to checkpoint-restart on its own. In this paper we describe the rMPI library which enables portable and transparent redundant computation for MPI applications. We detail the design of the library as well as two replica consistency protocols, outline the overheads of this library at scale on a number of real-world applications, and finally outline the significant increase in an applications time to solution at extreme scale as well as show the scenarios in which redundant computation makes sense.

  11. Automated Generation of Message-Passing Programs: An Evaluation Using CAPTools

    NASA Technical Reports Server (NTRS)

    Hribar, Michelle R.; Jin, Haoqiang; Yan, Jerry C.; Saini, Subhash (Technical Monitor)

    1998-01-01

    Scientists at NASA Ames Research Center have been developing computational aeroscience applications on highly parallel architectures over the past ten years. During that same time period, a steady transition of hardware and system software also occurred, forcing us to expend great efforts into migrating and re-coding our applications. As applications and machine architectures become increasingly complex, the cost and time required for this process will become prohibitive. In this paper, we present the first set of results in our evaluation of interactive parallelization tools. In particular, we evaluate CAPTool's ability to parallelize computational aeroscience applications. CAPTools was tested on serial versions of the NAS Parallel Benchmarks and ARC3D, a computational fluid dynamics application, on two platforms: the SGI Origin 2000 and the Cray T3E. This evaluation includes performance, amount of user interaction required, limitations and portability. Based on these results, a discussion on the feasibility of computer aided parallelization of aerospace applications is presented along with suggestions for future work.

  12. Chaos-pass filtering in injection-locked semiconductor lasers

    SciTech Connect

    Murakami, Atsushi; Shore, K. Alan

    2005-11-15

    Chaos-pass filtering (CPF) of semiconductor lasers has been studied theoretically. CPF is a phenomenon which occurs in laser chaos synchronization by injection locking and is a fundamental technique for the extraction of messages at the receiver laser in chaotic communications systems. We employ a simple theory based on driven damped oscillators to clarify the physical background of CPF. The receiver laser is optically driven by injection from the transmitter laser. We have numerically investigated the response characteristics of the receiver when it is driven by periodic (message) and chaotic (carrier) signals. It is thereby revealed that the response of the receiver laser in the two cases is quite different. For the periodic drive, the receiver exhibits a response depending on the signal frequency, while the chaotic drive provides a frequency-independent synchronous response to the receiver laser. We verify that the periodic and chaotic drives occur independently in the CPF response, and, consequently, CPF can be clearly understood in the difference of the two drives. Message extraction using CPF is also examined, and the validity of our theoretical explanation for the physical mechanism underlying CPF is thus verified.

  13. Chaos-pass filtering in injection-locked semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Murakami, Atsushi; Shore, K. Alan

    2005-11-01

    Chaos-pass filtering (CPF) of semiconductor lasers has been studied theoretically. CPF is a phenomenon which occurs in laser chaos synchronization by injection locking and is a fundamental technique for the extraction of messages at the receiver laser in chaotic communications systems. We employ a simple theory based on driven damped oscillators to clarify the physical background of CPF. The receiver laser is optically driven by injection from the transmitter laser. We have numerically investigated the response characteristics of the receiver when it is driven by periodic (message) and chaotic (carrier) signals. It is thereby revealed that the response of the receiver laser in the two cases is quite different. For the periodic drive, the receiver exhibits a response depending on the signal frequency, while the chaotic drive provides a frequency-independent synchronous response to the receiver laser. We verify that the periodic and chaotic drives occur independently in the CPF response, and, consequently, CPF can be clearly understood in the difference of the two drives. Message extraction using CPF is also examined, and the validity of our theoretical explanation for the physical mechanism underlying CPF is thus verified.

  14. NMACA Approach Used to Build a Secure Message Authentication Code

    NASA Astrophysics Data System (ADS)

    Alosaimy, Raed; Alghathbar, Khaled; Hafez, Alaaeldin M.; Eldefrawy, Mohamed H.

    Secure storage systems should consider the integrity and authentication of long-term stored information. When information is transferred through communication channels, different types of digital information can be represented, such as documents, images, and database tables. The authenticity of such information must be verified, especially when it is transferred through communication channels. Authentication verification techniques are used to verify that the information in an archive is authentic and has not been intentionally or maliciously altered. In addition to detecting malicious attacks, verifying the integrity also identifies data corruption. The purpose of Message Authentication Code (MAC) is to authenticate messages, where MAC algorithms are keyed hash functions. In most cases, MAC techniques use iterated hash functions, and these techniques are called iterated MACs. Such techniques usually use a MAC key as an input to the compression function, and this key is involved in the compression function, f, at every stage. Modification detection codes (MDCs) are un-keyed hash functions, and are widely used by authentication techniques such as MD4, MD5, SHA-1, and RIPEMD-160. There have been new attacks on hash functions such as MD5 and SHA-1, which requires the introduction of more secure hash functions. In this paper, we introduce a new MAC methodology that uses an input MAC key in the compression function, to change the order of the message words and shifting operation in the compression function. The new methodology can be used in conjunction with a wide range of modification detection code techniques. Using the SHA-1 algorithm as a model, a new (SHA-1)-MAC algorithm is presented. The (SHA-1)-MAC algorithm uses the MAC key to build the hash functions by defining the order for accessing source words and defining the number of bit positions for circular left shifts.

  15. Orangutan pantomime: elaborating the message

    PubMed Central

    Russon, Anne; Andrews, Kristin

    2011-01-01

    We present an exploratory study of forest-living orangutan pantomiming, i.e. gesturing in which they act out their meaning, focusing on its occurrence, communicative functions, and complexities. Studies show that captive great apes may elaborate messages if communication fails, and isolated reports suggest that great apes occasionally pantomime. We predicted forest-living orangutans would pantomime spontaneously to communicate, especially to elaborate after communication failures. Mining existing databases on free-ranging rehabilitant orangutans' behaviour identified 18 salient pantomimes. These pantomimes most often functioned as elaborations of failed requests, but also as deceptions and declaratives. Complexities identified include multimodality, re-enactments of past events and several features of language (productivity, compositionality, systematicity). These findings confirm that free-ranging rehabilitant orangutans pantomime and use pantomime to elaborate on their messages. Further, they use pantomime for multiple functions and create complex pantomimes that can express propositionally structured content. Thus, orangutan pantomime serves as a medium for communication, not a particular function. Mining cases of complex great ape communication originally reported in functional terms may then yield more evidence of pantomime. PMID:20702451

  16. Multi-pass light amplifier

    NASA Technical Reports Server (NTRS)

    Plaessmann, Henry (Inventor); Grossman, William M. (Inventor)

    1997-01-01

    A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A confocal resonator or White Cell resonator is provided, including two or three curvilinearly shaped mirrors facing each other along a resonator axis and an optical gain medium positioned on the resonator axis between the mirrors (confocal resonator) or adjacent to one of the mirrors (White Cell). In a first embodiment, two mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. The optical gain medium may be solid-state, liquid or gaseous medium and may be pumped longitudinally or transversely. In a second embodiment, first and second mirrors face a third mirror in a White Cell configuration, and the optical gain medium is positioned at or adjacent to one of the mirrors. Defocusing means and optical gain medium cooling means are optionally provided with either embodiment, to controllably defocus the light beam, to cool the optical gain medium and to suppress thermal lensing in the gain medium.

  17. The WLCG Messaging Service and its Future

    NASA Astrophysics Data System (ADS)

    Cons, Lionel; Paladin, Massimo

    2012-12-01

    Enterprise messaging is seen as an attractive mechanism to simplify and extend several portions of the Grid middleware, from low level monitoring to experiments dashboards. The production messaging service currently used by WLCG includes four tightly coupled brokers operated by EGI (running Apache ActiveMQ and designed to host the Grid operational tools such as SAM) as well as two dedicated services for ATLAS-DDM and experiments dashboards (currently also running Apache ActiveMQ). In the future, this service is expected to grow in numbers of applications supported, brokers and technologies. The WLCG Messaging Roadmap identified three areas with room for improvement (security, scalability and availability/reliability) as well as ten practical recommendations to address them. This paper describes a messaging service architecture that is in line with these recommendations as well as a software architecture based on reusable components that ease interactions with the messaging service. These two architectures will support the growth of the WLCG messaging service.

  18. CMLOG: A common message logging system

    SciTech Connect

    Chen, J.; Akers, W.; Bickley, M.; Wu, D.; Watson, W. III

    1997-12-01

    The Common Message Logging (CMLOG) system is an object-oriented and distributed system that not only allows applications and systems to log data (messages) of any type into a centralized database but also lets applications view incoming messages in real-time or retrieve stored data from the database according to selection rules. It consists of a concurrent Unix server that handles incoming logging or searching messages, a Motif browser that can view incoming messages in real-time or display stored data in the database, a client daemon that buffers and sends logging messages to the server, and libraries that can be used by applications to send data to or retrieve data from the database via the server. This paper presents the design and implementation of the CMLOG system meanwhile it will also address the issue of integration of CMLOG into existing control systems.

  19. Grammatical style of nutrition education messages.

    PubMed

    Geddes, F; Wise, A

    2001-01-01

    Nutrition education messages were written about eight different foods or food products in eight different styles. Styles were suggestions, instructions using 'should', rhetorical questions using 'how about' or 'why not', statements of fact, positive commands, positive commands followed by negative commands or vice versa. Subjects (n 160) rated messages for persuasiveness and also stated how often they already complied with each message. Scores were adjusted to remove the contributions related to sex, age group, social class, reported compliance and food about which the message had been written. The main factor influencing score for persuasiveness was the extent to which subjects claimed to be already complying with the messages. There were no significant effects of the method of construction of messages on score using one-way analysis of variance. PMID:11225184

  20. Algorithms and Algorithmic Languages.

    ERIC Educational Resources Information Center

    Veselov, V. M.; Koprov, V. M.

    This paper is intended as an introduction to a number of problems connected with the description of algorithms and algorithmic languages, particularly the syntaxes and semantics of algorithmic languages. The terms "letter, word, alphabet" are defined and described. The concept of the algorithm is defined and the relation between the algorithm and…

  1. Application of a Tsunami Warning Message Metric to refine NOAA NWS Tsunami Warning Messages

    NASA Astrophysics Data System (ADS)

    Gregg, C. E.; Johnston, D.; Sorensen, J.; Whitmore, P.

    2013-12-01

    In 2010, the U.S. National Weather Service (NWS) funded a three year project to integrate social science into their Tsunami Program. One of three primary requirements of the grant was to make improvements to tsunami warning messages of the NWS' two Tsunami Warning Centers- the West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii. We conducted focus group meetings with a purposive sample of local, state and Federal stakeholders and emergency managers in six states (AK, WA, OR, CA, HI and NC) and two US Territories (US Virgin Islands and American Samoa) to qualitatively asses information needs in tsunami warning messages using WCATWC tsunami messages for the March 2011 Tohoku earthquake and tsunami event. We also reviewed research literature on behavioral response to warnings to develop a tsunami warning message metric that could be used to guide revisions to tsunami warning messages of both warning centers. The message metric is divided into categories of Message Content, Style, Order and Formatting and Receiver Characteristics. A message is evaluated by cross-referencing the message with the operational definitions of metric factors. Findings are then used to guide revisions of the message until the characteristics of each factor are met. Using findings from this project and findings from a parallel NWS Warning Tiger Team study led by T. Nicolini, the WCATWC implemented the first of two phases of revisions to their warning messages in November 2012. A second phase of additional changes, which will fully implement the redesign of messages based on the metric, is in progress. The resulting messages will reflect current state-of-the-art knowledge on warning message effectiveness. Here we present the message metric; evidence-based rational for message factors; and examples of previous, existing and proposed messages.

  2. Evaluation of Sexual Communication Message Strategies

    PubMed Central

    2011-01-01

    Parent-child communication about sex is an important proximal reproductive health outcome. But while campaigns to promote it such as the Parents Speak Up National Campaign (PSUNC) have been effective, little is known about how messages influence parental cognitions and behavior. This study examines which message features explain responses to sexual communication messages. We content analyzed 4 PSUNC ads to identify specific, measurable message and advertising execution features. We then develop quantitative measures of those features, including message strategies, marketing strategies, and voice and other stylistic features, and merged the resulting data into a dataset drawn from a national media tracking survey of the campaign. Finally, we conducted multivariable logistic regression models to identify relationships between message content and ad reactions/receptivity, and between ad reactions/receptivity and parents' cognitions related to sexual communication included in the campaign's conceptual model. We found that overall parents were highly receptive to the PSUNC ads. We did not find significant associations between message content and ad reactions/receptivity. However, we found that reactions/receptivity to specific PSUNC ads were associated with increased norms, self-efficacy, short- and long-term expectations about parent-child sexual communication, as theorized in the conceptual model. This study extends previous research and methods to analyze message content and reactions/receptivity. The results confirm and extend previous PSUNC campaign evaluation and provide further evidence for the conceptual model. Future research should examine additional message content features and the effects of reactions/receptivity. PMID:21599875

  3. Identification of SPAM messages using an approach inspired on the immune system.

    PubMed

    Guzella, T S; Mota-Santos, T A; Uchôa, J Q; Caminhas, W M

    2008-06-01

    In this paper, an immune-inspired model, named innate and adaptive artificial immune system (IA-AIS) is proposed and applied to the problem of identification of unsolicited bulk e-mail messages (SPAM). It integrates entities analogous to macrophages, B and T lymphocytes, modeling both the innate and the adaptive immune systems. An implementation of the algorithm was capable of identifying more than 99% of legitimate or SPAM messages in particular parameter configurations. It was compared to an optimized version of the naive Bayes classifier, which has been attained extremely high correct classification rates. It has been concluded that IA-AIS has a greater ability to identify SPAM messages, although the identification of legitimate messages is not as high as that of the implemented naive Bayes classifier. PMID:18395967

  4. A new collage steganographic algorithm using cartoon design

    NASA Astrophysics Data System (ADS)

    Yi, Shuang; Zhou, Yicong; Pun, Chi-Man; Chen, C. L. Philip

    2014-02-01

    Existing collage steganographic methods suffer from low payload of embedding messages. To improve the payload while providing a high level of security protection to messages, this paper introduces a new collage steganographic algorithm using cartoon design. It embeds messages into the least significant bits (LSBs) of color cartoon objects, applies different permutations to each object, and adds objects to a cartoon cover image to obtain the stego image. Computer simulations and comparisons demonstrate that the proposed algorithm shows significantly higher capacity of embedding messages compared with existing collage steganographic methods.

  5. Efficient one-pass 3-D time migration

    SciTech Connect

    Brzostowski, M.A.; Snyder, F.F.C.; Smith, P.J.

    1996-11-01

    An efficient one-pass 3-D time migration algorithm is introduced as an alternative to Ristow`s splitting approach. This algorithm extends Black and Leong`s k{sub y}-separation approach with a time-dependent Stolt stretch operation called dilation. Migration using k{sub y} dilation consists of a single pass over the 3-D data volume after k{sub y} slices are formed with each k{sub y} slice downward continued independently. A number of downward continuation algorithms based upon the 3-D wave equation may be used. Dilation accommodates any lateral variations in velocity before the 3-D data volume is decomposed into k{sub y} slices via a Fourier transform. An inverse dilation operation is performed after the downward-continuation operation and after the data volume have been inverse Fourier transformed subsequently along the k{sub y} direction. Migration using the k{sub y}-dilation approach yields a one-pass 3-D time migration algorithm that is practical and efficient where the medium velocity is smoothly varying.

  6. Messages about Sexuality: An Ecological Perspective

    ERIC Educational Resources Information Center

    Boone, Tanya L.

    2015-01-01

    The goal of this two-part study was to identify the perceived influence of sexuality messages from parents, peers, school and the media--four microsystems within the Ecological Model--on emerging adult US college women's sexual attitudes. Findings suggest that parents were the most likely source of the message to "remain abstinent until…

  7. Hidden Messages: Instructional Materials for Investigating Culture.

    ERIC Educational Resources Information Center

    Finkelstein, Barbara, Ed.; Eder, Elizabeth K., Ed.

    This book, intended to be used in the middle and high school classroom, provides teachers with unique ideas and lesson plans for exploring culture and adding a multicultural perspective to diverse subjects. "Hidden messages" are the messages of culture that are entwined in everyday lives, but which are seldom recognized or appreciated for the…

  8. Message T-Shirts and School Safety

    ERIC Educational Resources Information Center

    Workman, Jane E.; Webb, Ashley L.; Freeburg, Beth Winfrey

    2011-01-01

    The purpose of this study was to investigate message T-shirts and school safety as rated by high school teachers (n = 47) and students (n = 275). Wearing message T-shirts displaying offensive statements/images may contribute to perceptions of a psychologically and/or physically unsafe school environment. Participants gave their impressions of 12…

  9. Context, Text, Message and Forms of Discourse.

    ERIC Educational Resources Information Center

    Britton, James

    This paper discusses the notion that comprehension of language involves an active interpretative process entailing both a generating of expectations and a matching of expectations to the "incoming message." There are, however, two forms of discourse in which the relation of text to message differs from that holding in ordinary language. One of…

  10. Literacy Messages, the Messenger and the Receiver.

    ERIC Educational Resources Information Center

    Fagan, William T.

    The message about general literacy standards in Canada (as reported in the Southam Literacy Survey) is that approximately five million Canadians are illiterate. The validity of this message must be challenged because a group of middle-class Canadians with middle-class values established the criteria for being "literate" and felt that all other…

  11. Memorable Messages for Navigating College Life

    ERIC Educational Resources Information Center

    Nazione, Samantha; Laplante, Carolyn; Smith, Sandi W.; Cornacchione, Jennifer; Russell, Jessica; Stohl, Cynthia

    2011-01-01

    This manuscript details an investigation of memorable messages that help students navigate college life using a control theory framework. Researchers conducted face-to-face interviews with 61 undergraduate students who recalled a specific memorable message that helped them as they navigated college. Results of this formative study show the…

  12. 78 FR 52166 - Quantitative Messaging Research

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-22

    ... COMMISSION Quantitative Messaging Research AGENCY: Commodity Futures Trading Commission. ACTION: Notice... qualitative message testing research (for which CFTC received fast-track OMB approval) and is necessary to... may deem to be inappropriate for publication, such as obscene language. All submissions that have...

  13. Text Messaging for Student Communication and Voting

    ERIC Educational Resources Information Center

    McClean, Stephen; Hagan, Paul; Morgan, Jason

    2010-01-01

    Text messaging has gained widespread popularity in higher education as a communication tool and as a means of engaging students in the learning process. In this study we report on the use of text messaging in a large, year-one introductory chemistry module where students were encouraged to send questions and queries to a dedicated text number both…

  14. Correlating Log Messages for System Diagnostics

    SciTech Connect

    Gunasekaran, Raghul; Dillow, David A; Shipman, Galen M; Maxwell, Don E; Hill, Jason J; Park, Byung H; Geist, Al

    2010-01-01

    In large-scale computing systems, the sheer volume of log data generated presents daunting challenges for debugging and monitoring of these systems. The Oak Ridge Leadership Computing Facility s premier simulation platform, the Cray XT5 known as Jaguar, can generate a few hundred thousand log entries in less than a minute for many system level events. Determining the root cause of such system events requires analyzing and interpretation of a large number of log messages. Most often, the log messages are best understood when they are interpreted collectively rather than individually. In this paper, we present our approach to interpreting log messages by identifying their commonalities and grouping them into clusters. Given a set of log messages within a time interval, we group the messages based on source, target, and/or error type, and correlate the messages with hardware and application information. We monitor the Lustre log messages in the XT5 console log and show that such grouping of log messages assists in detecting the source of system events. By intelligent grouping and correlation of events in the log, we are able to provide system administrators with meaningful information in a concise format for root cause analysis.

  15. Should We Ban Instant Messaging In School?

    ERIC Educational Resources Information Center

    Texley, Sharon; DeGennaro, Donna

    2005-01-01

    This article is a brief debate on the pros and cons of allowing students to use instant messaging (IM) in school. On one hand, teenagers' desire to socialize can overcome other priorities and schools may set policies to ban instant messaging. The contrary view is that schools should embrace the IM technology being popularized by youth and find…

  16. Developments in Children's Persuasive Message Practices.

    ERIC Educational Resources Information Center

    Kline, Susan L.; Clinton, Barbara L.

    1998-01-01

    Finds developmentally based systematic age changes in four of six persuasive-message practices in middle childhood: creating consensus about a problem, advocating a proposal, motivating the other to act, and building the other's self-concept. Notes that these age effects reflect children's evolving views about communication and messages as they…

  17. Coding for Parallel Links to Maximize the Expected Value of Decodable Messages

    NASA Technical Reports Server (NTRS)

    Klimesh, Matthew A.; Chang, Christopher S.

    2011-01-01

    When multiple parallel communication links are available, it is useful to consider link-utilization strategies that provide tradeoffs between reliability and throughput. Interesting cases arise when there are three or more available links. Under the model considered, the links have known probabilities of being in working order, and each link has a known capacity. The sender has a number of messages to send to the receiver. Each message has a size and a value (i.e., a worth or priority). Messages may be divided into pieces arbitrarily, and the value of each piece is proportional to its size. The goal is to choose combinations of messages to send on the links so that the expected value of the messages decodable by the receiver is maximized. There are three parts to the innovation: (1) Applying coding to parallel links under the model; (2) Linear programming formulation for finding the optimal combinations of messages to send on the links; and (3) Algorithms for assisting in finding feasible combinations of messages, as support for the linear programming formulation. There are similarities between this innovation and methods developed in the field of network coding. However, network coding has generally been concerned with either maximizing throughput in a fixed network, or robust communication of a fixed volume of data. In contrast, under this model, the throughput is expected to vary depending on the state of the network. Examples of error-correcting codes that are useful under this model but which are not needed under previous models have been found. This model can represent either a one-shot communication attempt, or a stream of communications. Under the one-shot model, message sizes and link capacities are quantities of information (e.g., measured in bits), while under the communications stream model, message sizes and link capacities are information rates (e.g., measured in bits/second). This work has the potential to increase the value of data returned from

  18. AMS: Area Message Service for SLC

    SciTech Connect

    Crane, M.; Mackenzie, R.; Millsom, D.; Zelazny, M.

    1993-04-01

    The Area Message Service (AMS) is a TCP/IP based messaging service currently in use at SLAC. A number of projects under development here at SLAC require and application level interface to the 4.3BSD UNIX socket level communications functions using TCP/IP over ethernet. AMS provides connection management, solicited message transfer, unsolicited message transfer, and asynchronous notification of pending messages. AMS is written completely in ANSI `C` and is currently portable over three hardware/operating system/network manager platforms, VAX/VMS/Multinet, PC/MS-DOS/Pathworks, VME 68K/pSOS/pNA. The basic architecture is a client-server connection where either end of the interface may be the server. This allows for connections and data flow to be initiated from either end of the interface. Included in the paper are details concerning the connection management, the handling of the multi-platform code, and the implementation process.

  19. Using franking machine messages to promote health.

    PubMed

    Harvey, J

    1988-01-01

    Over a 12-month period, the Oxfordshire Health Unit experimented with the addition of four different health promotion messages to all franked mail leaving the unit. Each message was evaluated by enclosing a return questionnaire in a sample of the mail. More than half the respondents read the messages (before seeing the questionnaire). Of all those who read the messages, 40 per cent said they would take some action as a result. Four out of five people thought the idea a good one. Using the evaluation results--including observed differences between the messages--some guidelines were created on the use of this relatively cost-effective form of health promotion. PMID:10288143

  20. Message from the Editor Message from the Editor

    NASA Astrophysics Data System (ADS)

    Thomas, Paul

    2012-04-01

    Whilst travelling to Vienna to hand over the Editorship of Nuclear Fusion to Ron Stambaugh, I jotted down a few ideas to put in a farewell message. Somewhat unsurprisingly, I find them almost identical to the remarks that Chris Schueller made in handing over to me five years ago. Both of us served in this role for five years, which seems like a good timescale to replace presidents and editors alike; just to allow a fresh approach. In addition, since I have been directly involved in ITER, I have found it increasingly difficult, due to time pressure, to give the journal the attention that it deserves. Therefore, I am very pleased that Ron Stambaugh has agreed to take over as Editor. Not only does he bring the experience as a leading figure in the US fusion programme but, in addition, he has all the contacts, worldwide, from his leadership of the ITPA. I am completely assured that the journal is in a highly competent pair of hands. Such a farewell should not lack my heartfelt thanks to all of those who have made being Editor of Nuclear Fusion so enjoyable and stimulating; readership, authors, referees, the Editorial Board and the NF Office alike. I wish Ron all the best for his tenure and have offered such help and support as I am able to give.

  1. A parallel dynamic programming algorithm for multi-reservoir system optimization

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Wei, Jiahua; Li, Tiejian; Wang, Guangqian; Yeh, William W.-G.

    2014-05-01

    This paper develops a parallel dynamic programming algorithm to optimize the joint operation of a multi-reservoir system. First, a multi-dimensional dynamic programming (DP) model is formulated for a multi-reservoir system. Second, the DP algorithm is parallelized using a peer-to-peer parallel paradigm. The parallelization is based on the distributed memory architecture and the message passing interface (MPI) protocol. We consider both the distributed computing and distributed computer memory in the parallelization. The parallel paradigm aims at reducing the computation time as well as alleviating the computer memory requirement associated with running a multi-dimensional DP model. Next, we test the parallel DP algorithm on the classic, benchmark four-reservoir problem on a high-performance computing (HPC) system with up to 350 cores. Results indicate that the parallel DP algorithm exhibits good performance in parallel efficiency; the parallel DP algorithm is scalable and will not be restricted by the number of cores. Finally, the parallel DP algorithm is applied to a real-world, five-reservoir system in China. The results demonstrate the parallel efficiency and practical utility of the proposed methodology.

  2. Portable and Transparent Message Compression in MPI Libraries to Improve the Performance and Scalability of Parallel Applications

    SciTech Connect

    Albonesi, David; Burtscher, Martin

    2009-04-17

    The goal of this project has been to develop a lossless compression algorithm for message-passing libraries that can accelerate HPC systems by reducing the communication time. Because both compression and decompression have to be performed in software in real time, the algorithm has to be extremely fast while still delivering a good compression ratio. During the first half of this project, they designed a new compression algorithm called FPC for scientific double-precision data, made the source code available on the web, and published two papers describing its operation, the first in the proceedings of the Data Compression Conference and the second in the IEEE Transactions on Computers. At comparable average compression ratios, this algorithm compresses and decompresses 10 to 100 times faster than BZIP2, DFCM, FSD, GZIP, and PLMI on the three architectures tested. With prediction tables that fit into the CPU's L1 data acache, FPC delivers a guaranteed throughput of six gigabits per second on a 1.6 GHz Itanium 2 system. The C source code and documentation of FPC are posted on-line and have already been downloaded hundreds of times. To evaluate FPC, they gathered 13 real-world scientific datasets from around the globe, including satellite data, crash-simulation data, and messages from HPC systems. Based on the large number of requests they received, they also made these datasets available to the community (with permission of the original sources). While FPC represents a great step forward, it soon became clear that its throughput was too slow for the emerging 10 gigabits per second networks. Hence, no speedup can be gained by including this algorithm in an MPI library. They therefore changed the aim of the second half of the project. Instead of implementing FPC in an MPI library, they refocused their efforts to develop a parallel compression algorithm to further boost the throughput. After all, all modern high-end microprocessors contain multiple CPUs on a single die

  3. Message communications of particular message types between compute nodes using DMA shadow buffers

    SciTech Connect

    Blocksome, Michael A.; Parker, Jeffrey J.

    2010-11-16

    Message communications of particular message types between compute nodes using DMA shadow buffers includes: receiving a buffer identifier specifying an application buffer having a message of a particular type for transmission to a target compute node through a network; selecting one of a plurality of shadow buffers for a DMA engine on the compute node for storing the message, each shadow buffer corresponding to a slot of an injection FIFO buffer maintained by the DMA engine; storing the message in the selected shadow buffer; creating a data descriptor for the message stored in the selected shadow buffer; injecting the data descriptor into the slot of the injection FIFO buffer corresponding to the selected shadow buffer; selecting the data descriptor from the injection FIFO buffer; and transmitting the message specified by the selected data descriptor through the data communications network to the target compute node.

  4. Improving the Effectiveness of Fundraising Messages: The Impact of Charity Goal Attainment, Message Framing, and Evidence on Persuasion

    ERIC Educational Resources Information Center

    Das, Enny; Kerkhof, Peter; Kuiper, Joyce

    2008-01-01

    This experimental study assessed the effectiveness of fundraising messages. Based on recent findings regarding the effects of message framing and evidence, effective fundraising messages should combine abstract, statistical information with a negative message frame and anecdotal evidence with a positive message frame. In addition, building on…

  5. Multi-pass light amplifier

    NASA Technical Reports Server (NTRS)

    Plaessmann, Henry (Inventor); Grossman, William M. (Inventor); Olson, Todd E. (Inventor)

    1996-01-01

    A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A resonator or a White Cell cavity is provided, including two or more mirrors (planar or curvilinearly shaped) facing each other along a resonator axis and an optical gain medium positioned on a resonator axis between the mirrors or adjacent to one of the mirrors. In a first embodiment, two curvilinear mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. A second embodiment uses two curvilinear mirrors and one planar mirror, with a gain medium positioned in the optical path between each curvilinear mirror and the planar mirror. A third embodiment uses two curvilinear mirrors and two planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses a curvilinear mirror and three planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses four planar mirrors and a focusing lens system, with a gain medium positioned between the four mirrors. A fifth embodiment uses first and second planar mirrors, a focusing lens system and a third mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the third mirror. A sixth embodiment uses two planar mirrors and a curvilinear mirror and a fourth mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the fourth mirror. In a seventh embodiment, first and second mirrors face a third

  6. Message Variability and Heterogeneity: A Core Challenge for Communication Research

    PubMed Central

    Slater, Michael D.; Peter, Jochen; Valkenberg, Patti

    2015-01-01

    Messages are central to human social experience, and pose key conceptual and methodological challenges in the study of communication. In response to these challenges, we outline a systematic approach to conceptualizing, operationalizing, and analyzing messages. At the conceptual level, we distinguish between two core aspects of messages: message variability (the defined and operationalized features of messages) and message heterogeneity (the undefined and unmeasured features of messages), and suggest preferred approaches to defining message variables. At the operational level, we identify message sampling, selection, and research design strategies responsive to issues of message variability and heterogeneity in experimental and survey research. At the analytical level, we highlight effective techniques to deal with message variability and heterogeneity. We conclude with seven recommendations to increase rigor in the study of communication through appropriately addressing the challenges presented by messages. PMID:26681816

  7. Communicating Concepts about Altruism in Interstellar Messages

    NASA Astrophysics Data System (ADS)

    Vakoch, Douglas A.

    2002-01-01

    This project identifies key principles of altruism that can be translated into interstellar messages for communication with extraterrestrial intelligence. The message contents will focus specifically on the evolution of altruism, drawing on recent insights in evolutionary biology, with particular emphasis on sociobiological accounts of kin selection and reciprocal altruism. This focus on altruism for message contents has several advantages. First, the subject can be translated into interstellar messages both via an existing formal interstellar language and via pictorial messages. For example, aspects of reciprocal altruism can be described through mathematical modeling, such as game theoretic approaches, which in turn can be described readily in the interstellar language Lincos. Second, concentrating on altruism as a message content may facilitate communications with extraterrestrial intelligence. Some scientists have argued that humans may be expected to communicate something about their moral status and development in an exchange with extraterrestrials. One of the most salient ways that terrestrial and extraterrestrial civilizations might be expected to evaluate one another is in terms of ethical motivations. Indeed, current search strategies assume some measure of altruism on the part of transmitting civilizations; with no guarantee of a response, the other civilization would be providing information to us with no direct payoff. Thus, concepts about altruism provide an appropriate content for interstellar messages, because the concepts themselves might be understood by extraterrestrial civilizations.

  8. A single pass electron accelerator

    NASA Astrophysics Data System (ADS)

    Schuetz, Marlin N.; Vroom, David A.

    1995-02-01

    Higher volumes, increasing competition and the need to improve quality have led us to re-examine the process for irradiation of tubing and wire. Traditionallyin Raychem, product irradiation has involved the use of large multi-purpose facilities that were designed to handle relatively small volumes of a large variety of products as a separate process. Today, with larger volumes of certain products, there is an interest in combining processes to improve quality and reduce cost. We have recently designed and constructed a small, low voltage accelerator system that can be placed in-line with another manufacturing process and can uniformly irradiate a tube or wire product in a single pass. The system is comprised of two conventional accelerator systems having elongated filaments and placed on opposite sides of a linear product path. The ribbon shaped electron beams from these two accelerators are scanned, after acceleration toward the product path, in a conventional manner and 180 degrees out of phase from each other. The two accelerated electron beams then enter a third magnetic field that is synchronous with the scanning magnets and whose oscillating polarity is such that the ribbon beams are converged onto a tubular shaped window close to and around a segment of the product path. Trials with a prototype system have produced tubing having a dose concentricity of better than ± 10 percent on a single pass through the system.

  9. A secure transmission scheme of streaming media based on the encrypted control message

    NASA Astrophysics Data System (ADS)

    Li, Bing; Jin, Zhigang; Shu, Yantai; Yu, Li

    2007-09-01

    As the use of streaming media applications increased dramatically in recent years, streaming media security becomes an important presumption, protecting the privacy. This paper proposes a new encryption scheme in view of characteristics of streaming media and the disadvantage of the living method: encrypt the control message in the streaming media with the high security lever and permute and confuse the data which is non control message according to the corresponding control message. Here the so-called control message refers to the key data of the streaming media, including the streaming media header and the header of the video frame, and the seed key. We encrypt the control message using the public key encryption algorithm which can provide high security lever, such as RSA. At the same time we make use of the seed key to generate key stream, from which the permutation list P responding to GOP (group of picture) is derived. The plain text of the non-control message XORs the key stream and gets the middle cipher text. And then obtained one is permutated according to P. In contrast the decryption process is the inverse process of the above. We have set up a testbed for the above scheme and found our scheme is six to eight times faster than the conventional method. It can be applied not only between PCs but also between handheld devices.

  10. Senate passes clean air bill

    NASA Astrophysics Data System (ADS)

    In an 89 to 11 vote the Senate passed a clean air bill aimed at reducing pollution by the turn of the century by imposing tougher controls on American industry. The bill is the first revision of the Clean Air Act of 1970 in 13 years and calls for new limits on auto pollution to clean up smog in most U.S. cities, decreasing by half emissions by power plants that cause acid rain to protect the ecology, and increasing technological controls on factories to protect against cancer-causing and toxic substances. The bill will add about $20 billion per year to the estimated $33 billion cost of complying with current pollution laws.

  11. LSB Based Quantum Image Steganography Algorithm

    NASA Astrophysics Data System (ADS)

    Jiang, Nan; Zhao, Na; Wang, Luo

    2016-01-01

    Quantum steganography is the technique which hides a secret message into quantum covers such as quantum images. In this paper, two blind LSB steganography algorithms in the form of quantum circuits are proposed based on the novel enhanced quantum representation (NEQR) for quantum images. One algorithm is plain LSB which uses the message bits to substitute for the pixels' LSB directly. The other is block LSB which embeds a message bit into a number of pixels that belong to one image block. The extracting circuits can regain the secret message only according to the stego cover. Analysis and simulation-based experimental results demonstrate that the invisibility is good, and the balance between the capacity and the robustness can be adjusted according to the needs of applications.

  12. Six-Message Electromechanical Display System

    NASA Technical Reports Server (NTRS)

    Howard, Richard T.

    2007-01-01

    A proposed electromechanical display system would be capable of presenting as many as six distinct messages. In the proposed system, each display element would include a cylinder having a regular hexagonal cross section.

  13. Message for Heart Failure Patients: Exercise

    MedlinePlus

    ... fullstory_159059.html Message for Heart Failure Patients: Exercise You'll feel better and maybe even live ... with heart failure should not be scared of exercise damaging them or killing them," said principal investigator ...

  14. Books about Teen Parents: Messages and Omissions.

    ERIC Educational Resources Information Center

    Davis, Joy B.; MacGillivray, Laurie

    2001-01-01

    Examines narratives and novels written for young adults that deal with teenage pregnancy and parenting. Discusses eight common messages found in 17 such short stories and books, and notes three areas of significant silence. (SR)

  15. Fear, threat and efficacy in threat appeals: message involvement as a key mediator to message acceptance.

    PubMed

    Cauberghe, Verolien; De Pelsmacker, Patrick; Janssens, Wim; Dens, Nathalie

    2009-03-01

    In a sample of 170 youngsters, the effect of two versions of a public service announcement (PSA) threat appeal against speeding, placed in four different contexts, on evoked fear, perceived threat (severity and probability of occurrence), perceived response efficacy and self-efficacy, message involvement and anti-speeding attitude and anti-speeding intention is investigated. Evoked fear and perceived threat and efficacy independently influence message involvement. Message involvement is a full mediator between evoked fear, perceived threat and efficacy perception on the one hand, and attitudes towards the message and behavioral intention to accept the message on the other. Speeding experience has a significantly negative impact on anti-speeding attitudes. Message and medium context threat levels and context thematic congruency have a significant effect on evoked fear and to a lesser extent on perceived threat. PMID:19245886

  16. The effect of bioterrorism messages on anxiety levels.

    PubMed

    Lightstone, Sandra N; Swencionis, Charles; Cohen, Hillel W

    Public health messages sometimes use graphic language to discourage health-adverse behaviors. However, such messages could provoke adverse stress and anxiety reactions. To assess whether public health messages on bioterrorism might measurably increase stress and anxiety, we conducted a randomized controlled trial in which potent and neutral messages were randomly allocated to 116 graduate students. Pre- and post-message anxiety scores of the State-Trait Anxiety Inventory (STAI), a validated instrument, were recorded, and within- and between-group score changes compared. Reading the potent message significantly (p=.003) elevated STAI anxiety scores, while reading the neutral messages decreased scores (p<.001). The between-group difference was also statistically significant (p=.001). Potent smoking and drunk-driving cessation messages have clear benefits, but messages about bioterrorism do not. Our findings provide evidence that such messages have at least the potential of harm, so that weighing benefits and risks of such messages is warranted. PMID:17686681

  17. Mood and processing of proattitudinal and counterattitudinal messages.

    PubMed

    Ziegler, Rene

    2013-04-01

    Existing research has established the effects of mood on processing of clearly mood-elevating proattitudinal messages and clearly mood-threatening counterattitudinal messages (i.e., mood-relevant messages). Little is known, however, about mood effects on processing of less mood-elevating proattitudinal messages and less mood-threatening counterattitudinal messages (i.e., mood-irrelevant messages). The present research tested hypotheses regarding processing of mood-irrelevant messages based on a mood-congruent expectancies approach. Specifically, two studies were conducted in which prior attitudes were measured (Study 1) or manipulated (Study 2). As predicted, results showed higher scrutiny in negative mood given a proattitudinal message and in positive mood given a counterattitudinal message than in negative mood given a counterattitudinal message and in positive mood given a proattitudinal message. Discussion focuses on implications regarding the accumulated literature, different accounts proposed to understand mood effects on processing effort, and further research. PMID:23436770

  18. Send-side matching of data communications messages

    SciTech Connect

    Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

    2014-06-17

    Send-side matching of data communications messages in a distributed computing system comprising a plurality of compute nodes, including: issuing by a receiving node to source nodes a receive message that specifies receipt of a single message to be sent from any source node, the receive message including message matching information, a specification of a hardware-level mutual exclusion device, and an identification of a receive buffer; matching by two or more of the source nodes the receive message with pending send messages in the two or more source nodes; operating by one of the source nodes having a matching send message the mutual exclusion device, excluding messages from other source nodes with matching send messages and identifying to the receiving node the source node operating the mutual exclusion device; and sending to the receiving node from the source node operating the mutual exclusion device a matched pending message.

  19. Send-side matching of data communications messages

    SciTech Connect

    Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

    2014-07-01

    Send-side matching of data communications messages includes a plurality of compute nodes organized for collective operations, including: issuing by a receiving node to source nodes a receive message that specifies receipt of a single message to be sent from any source node, the receive message including message matching information, a specification of a hardware-level mutual exclusion device, and an identification of a receive buffer; matching by two or more of the source nodes the receive message with pending send messages in the two or more source nodes; operating by one of the source nodes having a matching send message the mutual exclusion device, excluding messages from other source nodes with matching send messages and identifying to the receiving node the source node operating the mutual exclusion device; and sending to the receiving node from the source node operating the mutual exclusion device a matched pending message.

  20. Effect of multiple extrusion passes on zein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zein was repeatedly processed up to seven times using a single screw extruder at a temperature of 145 °C and at approximately 15 grams per minute to determine the extent of degradation that occurs with multiple extrusion passes. SDS-PAGE shows that with the second pass, and each additional pass, the...

  1. Cockpit Interfaces, Displays, and Alerting Messages for the Interval Management Alternative Clearances (IMAC) Experiment

    NASA Technical Reports Server (NTRS)

    Baxley, Brian T.; Palmer, Michael T.; Swieringa, Kurt A.

    2015-01-01

    This document describes the IM cockpit interfaces, displays, and alerting capabilities that were developed for and used in the IMAC experiment, which was conducted at NASA Langley in the summer of 2015. Specifically, this document includes: (1) screen layouts for each page of the interface; (2) step-by-step instructions for data entry, data verification and input error correction; (3) algorithm state messages and error condition alerting messages; (4) aircraft speed guidance and deviation indications; and (5) graphical display of the spatial relationships between the Ownship aircraft and the Target aircraft. The controller displays for IM will be described in a separate document.

  2. Iterative pass optimization of sequence data

    NASA Technical Reports Server (NTRS)

    Wheeler, Ward C.

    2003-01-01

    The problem of determining the minimum-cost hypothetical ancestral sequences for a given cladogram is known to be NP-complete. This "tree alignment" problem has motivated the considerable effort placed in multiple sequence alignment procedures. Wheeler in 1996 proposed a heuristic method, direct optimization, to calculate cladogram costs without the intervention of multiple sequence alignment. This method, though more efficient in time and more effective in cladogram length than many alignment-based procedures, greedily optimizes nodes based on descendent information only. In their proposal of an exact multiple alignment solution, Sankoff et al. in 1976 described a heuristic procedure--the iterative improvement method--to create alignments at internal nodes by solving a series of median problems. The combination of a three-sequence direct optimization with iterative improvement and a branch-length-based cladogram cost procedure, provides an algorithm that frequently results in superior (i.e., lower) cladogram costs. This iterative pass optimization is both computation and memory intensive, but economies can be made to reduce this burden. An example in arthropod systematics is discussed. c2003 The Willi Hennig Society. Published by Elsevier Science (USA). All rights reserved.

  3. Iterative pass optimization of sequence data.

    PubMed

    Wheeler, Ward C

    2003-06-01

    The problem of determining the minimum-cost hypothetical ancestral sequences for a given cladogram is known to be NP-complete. This "tree alignment" problem has motivated the considerable effort placed in multiple sequence alignment procedures. Wheeler in 1996 proposed a heuristic method, direct optimization, to calculate cladogram costs without the intervention of multiple sequence alignment. This method, though more efficient in time and more effective in cladogram length than many alignment-based procedures, greedily optimizes nodes based on descendent information only. In their proposal of an exact multiple alignment solution, Sankoff et al. in 1976 described a heuristic procedure--the iterative improvement method--to create alignments at internal nodes by solving a series of median problems. The combination of a three-sequence direct optimization with iterative improvement and a branch-length-based cladogram cost procedure, provides an algorithm that frequently results in superior (i.e., lower) cladogram costs. This iterative pass optimization is both computation and memory intensive, but economies can be made to reduce this burden. An example in arthropod systematics is discussed. PMID:12901382

  4. A De-Centralized Scheduling and Load Balancing Algorithm for Heterogeneous Grid Environments

    NASA Technical Reports Server (NTRS)

    Arora, Manish; Das, Sajal K.; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2002-01-01

    In the past two decades, numerous scheduling and load balancing techniques have been proposed for locally distributed multiprocessor systems. However, they all suffer from significant deficiencies when extended to a Grid environment: some use a centralized approach that renders the algorithm unscalable, while others assume the overhead involved in searching for appropriate resources to be negligible. Furthermore, classical scheduling algorithms do not consider a Grid node to be N-resource rich and merely work towards maximizing the utilization of one of the resources. In this paper we propose a new scheduling and load balancing algorithm for a generalized Grid model of N-resource nodes that not only takes into account the node and network heterogeneity, but also considers the overhead involved in coordinating among the nodes. Our algorithm is de-centralized, scalable, and overlaps the node coordination time of the actual processing of ready jobs, thus saving valuable clock cycles needed for making decisions. The proposed algorithm is studied by conducting simulations using the Message Passing Interface (MPI) paradigm.

  5. A De-centralized Scheduling and Load Balancing Algorithm for Heterogeneous Grid Environments

    NASA Technical Reports Server (NTRS)

    Arora, Manish; Das, Sajal K.; Biswas, Rupak

    2002-01-01

    In the past two decades, numerous scheduling and load balancing techniques have been proposed for locally distributed multiprocessor systems. However, they all suffer from significant deficiencies when extended to a Grid environment: some use a centralized approach that renders the algorithm unscalable, while others assume the overhead involved in searching for appropriate resources to be negligible. Furthermore, classical scheduling algorithms do not consider a Grid node to be N-resource rich and merely work towards maximizing the utilization of one of the resources. In this paper, we propose a new scheduling and load balancing algorithm for a generalized Grid model of N-resource nodes that not only takes into account the node and network heterogeneity, but also considers the overhead involved in coordinating among the nodes. Our algorithm is decentralized, scalable, and overlaps the node coordination time with that of the actual processing of ready jobs, thus saving valuable clock cycles needed for making decisions. The proposed algorithm is studied by conducting simulations using the Message Passing Interface (MPI) paradigm.

  6. Efficient implementation of Jacobi algorithms and Jacobi sets on distributed memory architectures

    NASA Astrophysics Data System (ADS)

    Eberlein, P. J.; Park, Haesun

    1990-04-01

    One-sided methods for implementing Jacobi diagonalization algorithms have been recently proposed for both distributed memory and vector machines. These methods are naturally well suited to distributed memory and vector architectures because of their inherent parallelism and their abundance of vector operations. Also, one-sided methods require substantially less message passing than the two-sided methods, and thus can achieve higher efficiency. We describe in detail the use of the one-sided Jacobi rotation as opposed to the rotation used in the ``Hestenes'' algorithm; we perceive this difference to have been widely misunderstood. Furthermore the one-sided algorithm generalizes to other problems such as the nonsymmetric eigenvalue problem while the Hestenes algorithm does not. We discuss two new implementations for Jacobi sets for a ring connected array of processors and show their isomorphism to the round-robin ordering. Moreover, we show that two implementations produce Jacobi sets in identical orders up to a relabeling. These orderings are optimal in the sense that they complete each sweep in a minimum number of stages with minimal communication. We present implementation results of one-sided Jacobi algorithms using these orderings on the NCUBE/seven hypercube as well as the Intel iPSC/2 hypercube. Finally, we mention how other orderings, and can be, implemented. The number of nonisomorphic Jacobi sets has recently been shown to become infinite with increasing n. The work of this author was supported by National Science Foundation Grant CCR-8813493.

  7. Information Theory, Inference and Learning Algorithms

    NASA Astrophysics Data System (ADS)

    Mackay, David J. C.

    2003-10-01

    Information theory and inference, often taught separately, are here united in one entertaining textbook. These topics lie at the heart of many exciting areas of contemporary science and engineering - communication, signal processing, data mining, machine learning, pattern recognition, computational neuroscience, bioinformatics, and cryptography. This textbook introduces theory in tandem with applications. Information theory is taught alongside practical communication systems, such as arithmetic coding for data compression and sparse-graph codes for error-correction. A toolbox of inference techniques, including message-passing algorithms, Monte Carlo methods, and variational approximations, are developed alongside applications of these tools to clustering, convolutional codes, independent component analysis, and neural networks. The final part of the book describes the state of the art in error-correcting codes, including low-density parity-check codes, turbo codes, and digital fountain codes -- the twenty-first century standards for satellite communications, disk drives, and data broadcast. Richly illustrated, filled with worked examples and over 400 exercises, some with detailed solutions, David MacKay's groundbreaking book is ideal for self-learning and for undergraduate or graduate courses. Interludes on crosswords, evolution, and sex provide entertainment along the way. In sum, this is a textbook on information, communication, and coding for a new generation of students, and an unparalleled entry point into these subjects for professionals in areas as diverse as computational biology, financial engineering, and machine learning.

  8. 47 CFR 32.5100 - Long distance message revenue.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Long distance message revenue. 32.5100 Section... Long distance message revenue. This account shall include revenue derived from message services that... includes those message services which utilize the public long distance switching network and the...

  9. 47 CFR 32.5100 - Long distance message revenue.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Long distance message revenue. 32.5100 Section... Long distance message revenue. This account shall include revenue derived from message services that... includes those message services which utilize the public long distance switching network and the...

  10. 47 CFR 32.5100 - Long distance message revenue.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Long distance message revenue. 32.5100 Section... Long distance message revenue. This account shall include revenue derived from message services that... includes those message services which utilize the public long distance switching network and the...

  11. 47 CFR 32.5100 - Long distance message revenue.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Long distance message revenue. 32.5100 Section... Long distance message revenue. This account shall include revenue derived from message services that... includes those message services which utilize the public long distance switching network and the...

  12. Dynamic hybrid algorithms for MAP inference in discrete MRFs.

    PubMed

    Alahari, Karteek; Kohli, Pushmeet; Torr, Philip H S

    2010-10-01

    In this paper, we present novel techniques that improve the computational and memory efficiency of algorithms for solving multilabel energy functions arising from discrete mrfs or crfs. These methods are motivated by the observations that the performance of minimization algorithms depends on: 1) the initialization used for the primal and dual variables and 2) the number of primal variables involved in the energy function. Our first method (dynamic alpha-expansion) works by "recycling" results from previous problem instances. The second method simplifies the energy function by "reducing" the number of unknown variables present in the problem. Further, we show that it can also be used to generate a good initialization for the dynamic alpha-expansion algorithm by "reusing" dual variables. We test the performance of our methods on energy functions encountered in the problems of stereo matching and color and object-based segmentation. Experimental results show that our methods achieve a substantial improvement in the performance of alpha-expansion, as well as other popular algorithms such as sequential tree-reweighted message passing and max-product belief propagation. We also demonstrate the applicability of our schemes for certain higher order energy functions, such as the one described in [1], for interactive texture-based image and video segmentation. In most cases, we achieve a 10-15 times speed-up in the computation time. Our modified alpha-expansion algorithm provides similar performance to Fast-PD, but is conceptually much simpler. Both alpha-expansion and Fast-PD can be made orders of magnitude faster when used in conjunction with the "reduce" scheme proposed in this paper. PMID:20724761

  13. Relational Uncertainty and Message Production within Courtship: Features of Date Request Messages

    ERIC Educational Resources Information Center

    Knobloch, Leanne K.

    2006-01-01

    This paper theorizes about how relational uncertainty may predict features of date request messages within courtship. It reports a study in which 248 individuals role-played leaving a date request voice mail message for their partner. Relational uncertainty was negatively associated with the fluency (H1), affiliativeness (H2), relationship focus…

  14. Can Messages Make a Difference? The Association between E-Mail Messages and Health Outcomes in Diabetes Patients

    ERIC Educational Resources Information Center

    Turner, Jeanine Warisse; Robinson, James D.; Tian, Yan; Neustadtl, Alan; Angelus, Pam; Russell, Marie; Mun, Seong K.; Levine, Betty

    2013-01-01

    This investigation examined the impact of social support messages on patient health outcomes. Forty-one American Indian, Alaska Native, and Native Hawaiian patients received a total of 618 e-mail messages from their healthcare provider (HCP). The e-mail messages were divided into 3,565 message units and coded for instances of emotional social…

  15. Supervising simulations with the Prodiguer Messaging Platform

    NASA Astrophysics Data System (ADS)

    Greenslade, Mark; Carenton, Nicolas; Denvil, Sebastien

    2015-04-01

    At any one moment in time, researchers affiliated with the Institut Pierre Simon Laplace (IPSL) climate modeling group, are running hundreds of global climate simulations. These simulations execute upon a heterogeneous set of High Performance Computing (HPC) environments spread throughout France. The IPSL's simulation execution runtime is called libIGCM (library for IPSL Global Climate Modeling group). libIGCM has recently been enhanced so as to support realtime operational use cases. Such use cases include simulation monitoring, data publication, environment metrics collection, automated simulation control … etc. At the core of this enhancement is the Prodiguer messaging platform. libIGCM now emits information, in the form of messages, for remote processing at IPSL servers in Paris. The remote message processing takes several forms, for example: 1. Persisting message content to database(s); 2. Notifying an operator of changes in a simulation's execution status; 3. Launching rollback jobs upon simulation failure; 4. Dynamically updating controlled vocabularies; 5. Notifying downstream applications such as the Prodiguer web portal; We will describe how the messaging platform has been implemented from a technical perspective and demonstrate the Prodiguer web portal receiving realtime notifications.

  16. Positive messaging promotes walking in older adults

    PubMed Central

    Notthoff, Nanna; Carstensen, Laura L.

    2014-01-01

    Walking is among the most cost-effective and accessible means of exercise. Mounting evidence suggests that walking may help to maintain physical and cognitive independence in old age by preventing a variety of health problems. However, older Americans fall far short of meeting the daily recommendations for walking. In two studies, we examined whether considering older adults’ preferential attention to positive information may effectively enhance interventions aimed at promoting walking. In Study 1, we compared the effectiveness of positive, negative, and neutral messages to encourage walking (as measured with pedometers). Older adults who were informed about the benefits of walking walked more than those who were informed about the negative consequences of failing to walk, whereas younger adults were unaffected by framing valence. In Study 2, we examined within-person change in walking in older adults in response to positively- or negatively-framed messages over a 28-day period. Once again, positively-framed messages more effectively promoted walking than negatively-framed messages, and the effect was sustained across the intervention period. Together, these studies suggest that consideration of age-related changes in preferences for positive and negative information may inform the design of effective interventions to promote healthy lifestyles. Future research is needed to examine the mechanisms underlying the greater effectiveness of positively as opposed to negatively framed messages and the generalizability of findings to other intervention targets and other subpopulations of older adults. PMID:24956001

  17. Low Latency Messages on Distributed Memory Multiprocessors

    DOE PAGESBeta

    Rosing, Matt; Saltz, Joel

    1995-01-01

    This article describes many of the issues in developing an efficient interface for communication on distributed memory machines. Although the hardware component of message latency is less than 1 ws on many distributed memory machines, the software latency associated with sending and receiving typed messages is on the order of 50 μs. The reason for this imbalance is that the software interface does not match the hardware. By changing the interface to match the hardware more closely, applications with fine grained communication can be put on these machines. This article describes several tests performed and many of the issues involvedmore » in supporting low latency messages on distributed memory machines.« less

  18. Broadcasting a message in a parallel computer

    DOEpatents

    Berg, Jeremy E.; Faraj, Ahmad A.

    2011-08-02

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer. The parallel computer includes a plurality of compute nodes connected together using a data communications network. The data communications network optimized for point to point data communications and is characterized by at least two dimensions. The compute nodes are organized into at least one operational group of compute nodes for collective parallel operations of the parallel computer. One compute node of the operational group assigned to be a logical root. Broadcasting a message in a parallel computer includes: establishing a Hamiltonian path along all of the compute nodes in at least one plane of the data communications network and in the operational group; and broadcasting, by the logical root to the remaining compute nodes, the logical root's message along the established Hamiltonian path.

  19. Pass-transistor very large scale integration

    NASA Technical Reports Server (NTRS)

    Maki, Gary K. (Inventor); Bhatia, Prakash R. (Inventor)

    2004-01-01

    Logic elements are provided that permit reductions in layout size and avoidance of hazards. Such logic elements may be included in libraries of logic cells. A logical function to be implemented by the logic element is decomposed about logical variables to identify factors corresponding to combinations of the logical variables and their complements. A pass transistor network is provided for implementing the pass network function in accordance with this decomposition. The pass transistor network includes ordered arrangements of pass transistors that correspond to the combinations of variables and complements resulting from the logical decomposition. The logic elements may act as selection circuits and be integrated with memory and buffer elements.

  20. Photoacoustic Soot Spectrometer (PASS) Instrument Handbook

    SciTech Connect

    Dubey, M; Springston, S; Koontz, A; Aiken, A

    2013-01-17

    The photoacoustic soot spectrometer (PASS) measures light absorption by aerosol particles. As the particles pass through a laser beam, the absorbed energy heats the particles and in turn the surrounding air, which sets off a pressure wave that can be detected by a microphone. The PASS instruments deployed by ARM can also simultaneously measure the scattered laser light at three wavelengths and therefore provide a direct measure of the single-scattering albedo. The Operator Manual for the PASS-3100 is included here with the permission of Droplet Measurement Technologies, the instrument’s manufacturer.

  1. EDITORIAL: Message from the Editor Message from the Editor

    NASA Astrophysics Data System (ADS)

    Thomas, Paul

    2010-02-01

    passing away of the following former members of the Board of Editors: Ravindra Sudan (1975 to 1984), Joe Di Marco (1984 to 1991) and Roy Bickerton (1975 to 1986). The Nuclear Fusion Office and IOP Publishing Just as the journal depends on the authors and referees, so its success is also due to the tireless and largely unsung efforts of the Nuclear Fusion Office in Vienna and IOP Publishing in Bristol. I would like to express my personal thanks to Maria Bergamini-Roedler, Katja Haslinger, Sophy Le Masurier, Yasmin McGlashan, Caroline Wilkinson, Sarah Ryder, Rachael Kriefman and Katie Gerrard for the support that they have given to me, the authors and the referees. Season's Greetings The January special edition delayed this editorial for a month. Nevertheless, I would like belatedly to wish our readers, authors, referees and Board of Editors the season's greetings and thank them for their contributions to Nuclear Fusion in 2009.

  2. Developing effective messages about potable recycled water: The importance of message structure and content

    NASA Astrophysics Data System (ADS)

    Price, J.; Fielding, K. S.; Gardner, J.; Leviston, Z.; Green, M.

    2015-04-01

    Community opposition is a barrier to potable recycled water schemes. Effective communication strategies about such schemes are needed. Drawing on social psychological literature, two experimental studies are presented, which explore messages that improve public perceptions of potable recycled water. The Elaboration-Likelihood Model of information processing and attitude change is tested and supported. Study 1 (N = 415) premeasured support for recycled water, and trust in government information at Time 1. Messages varied in complexity and sidedness were presented at Time 2 (3 weeks later), and support and trust were remeasured. Support increased after receiving information, provided that participants received complex rather than simple information. Trust in government was also higher after receiving information. There was tentative evidence of this in response to two-sided messages rather than one-sided messages. Initial attitudes to recycled water moderated responses to information. Those initially neutral or ambivalent responded differently to simple and one-sided messages, compared to participants with positive or negative attitudes. Study 2 (N = 957) tested the effectiveness of information about the low relative risks, and/or benefits of potable recycled water, compared to control groups. Messages about the low risks resulted in higher support when the issue of recycled water was relevant. Messages about benefits resulted in higher perceived issue relevance, but did not translate into greater support. The results highlight the importance of understanding people's motivation to process information, and need to tailor communication to match attitudes and stage of recycled water schemes' development.

  3. A Parallel, Finite-Volume Algorithm for Large-Eddy Simulation of Turbulent Flows

    NASA Technical Reports Server (NTRS)

    Bui, Trong T.

    1999-01-01

    A parallel, finite-volume algorithm has been developed for large-eddy simulation (LES) of compressible turbulent flows. This algorithm includes piecewise linear least-square reconstruction, trilinear finite-element interpolation, Roe flux-difference splitting, and second-order MacCormack time marching. Parallel implementation is done using the message-passing programming model. In this paper, the numerical algorithm is described. To validate the numerical method for turbulence simulation, LES of fully developed turbulent flow in a square duct is performed for a Reynolds number of 320 based on the average friction velocity and the hydraulic diameter of the duct. Direct numerical simulation (DNS) results are available for this test case, and the accuracy of this algorithm for turbulence simulations can be ascertained by comparing the LES solutions with the DNS results. The effects of grid resolution, upwind numerical dissipation, and subgrid-scale dissipation on the accuracy of the LES are examined. Comparison with DNS results shows that the standard Roe flux-difference splitting dissipation adversely affects the accuracy of the turbulence simulation. For accurate turbulence simulations, only 3-5 percent of the standard Roe flux-difference splitting dissipation is needed.

  4. An events based algorithm for distributing concurrent tasks on multi-core architectures

    NASA Astrophysics Data System (ADS)

    Holmes, David W.; Williams, John R.; Tilke, Peter

    2010-02-01

    In this paper, a programming model is presented which enables scalable parallel performance on multi-core shared memory architectures. The model has been developed for application to a wide range of numerical simulation problems. Such problems involve time stepping or iteration algorithms where synchronization of multiple threads of execution is required. It is shown that traditional approaches to parallelism including message passing and scatter-gather can be improved upon in terms of speed-up and memory management. Using spatial decomposition to create orthogonal computational tasks, a new task management algorithm called H-Dispatch is developed. This algorithm makes efficient use of memory resources by limiting the need for garbage collection and takes optimal advantage of multiple cores by employing a "hungry" pull strategy. The technique is demonstrated on a simple finite difference solver and results are compared to traditional MPI and scatter-gather approaches. The H-Dispatch approach achieves near linear speed-up with results for efficiency of 85% on a 24-core machine. It is noted that the H-Dispatch algorithm is quite general and can be applied to a wide class of computational tasks on heterogeneous architectures involving multi-core and GPGPU hardware.

  5. A scalable projective scaling algorithm for l(p) loss with convex penalizations.

    PubMed

    Zhou, Hongbo; Cheng, Qiang

    2015-02-01

    This paper presents an accurate, efficient, and scalable algorithm for minimizing a special family of convex functions, which have a lp loss function as an additive component. For this problem, well-known learning algorithms often have well-established results on accuracy and efficiency, but there exists rarely any report on explicit linear scalability with respect to the problem size. The proposed approach starts with developing a second-order learning procedure with iterative descent for general convex penalization functions, and then builds efficient algorithms for a restricted family of functions, which satisfy the Karmarkar's projective scaling condition. Under this condition, a light weight, scalable message passing algorithm (MPA) is further developed by constructing a series of simpler equivalent problems. The proposed MPA is intrinsically scalable because it only involves matrix-vector multiplication and avoids matrix inversion operations. The MPA is proven to be globally convergent for convex formulations; for nonconvex situations, it converges to a stationary point. The accuracy, efficiency, scalability, and applicability of the proposed method are verified through extensive experiments on sparse signal recovery, face image classification, and over-complete dictionary learning problems. PMID:25608289

  6. What's in a message? Delivering sexual health promotion to young people in Australia via text messaging

    PubMed Central

    2010-01-01

    Background Advances in communication technologies have dramatically changed how individuals access information and communicate. Recent studies have found that mobile phone text messages (SMS) can be used successfully for short-term behaviour change. However there is no published information examining the acceptability, utility and efficacy of different characteristics of health promotion SMS. This paper presents the results of evaluation focus groups among participants who received twelve sexual health related SMS as part of a study examining the impact of text messaging for sexual health promotion to on young people in Victoria, Australia. Methods Eight gender-segregated focus groups were held with 21 males and 22 females in August 2008. Transcripts of audio recordings were analysed using thematic analysis. Data were coded under one or more themes. Results Text messages were viewed as an acceptable and 'personal' means of health promotion, with participants particularly valuing the informal language. There was a preference for messages that were positive, relevant and short and for messages to cover a variety of topics. Participants were more likely to remember and share messages that were funny, rhymed and/or tied into particular annual events. The message broadcasting, generally fortnightly on Friday afternoons, was viewed as appropriate. Participants said the messages provided new information, a reminder of existing information and reduced apprehension about testing for sexually transmitted infections. Conclusions Mobile phones, in particular SMS, offer health promoters an exciting opportunity to engage personally with a huge number of individuals for low cost. The key elements emerging from this evaluation, such as message style, language and broadcast schedule are directly relevant to future studies using SMS for health promotion, as well as for future health promotion interventions in other mediums that require short formats, such as social networking sites

  7. UAVSAR: Airborne L-band Radar for Repeat Pass Interferometry

    NASA Technical Reports Server (NTRS)

    Moes, Timothy R.

    2009-01-01

    The primary objectives of the UAVSAR Project were to: a) develop a miniaturized polarimetric L-band synthetic aperture radar (SAR) for use on an unmanned aerial vehicle (UAV) or piloted vehicle. b) develop the associated processing algorithms for repeat-pass differential interferometric measurements using a single antenna. c) conduct measurements of geophysical interest, particularly changes of rapidly deforming surfaces such as volcanoes or earthquakes. Two complete systems were developed. Operational Science Missions began on February 18, 2009 ... concurrent development and testing of the radar system continues.

  8. Alcohol Messages in Prime-Time Television Series

    PubMed Central

    RUSSELL, CRISTEL ANTONIA; RUSSELL, DALE W.

    2010-01-01

    Alcohol messages contained in television programming serve as sources of information about drinking. To better understand the ways embedded messages about alcohol are communicated, it is crucial to objectively monitor and analyze television alcohol depictions. This article presents a content analysis of an eight-week sample of eighteen prime-time programs. Alcohol messages were coded based on modalities of presentation, level of plot connection, and valence. The analysis reveals that mixed messages about alcohol often coexist but the ways in which they are presented differ: whereas negative messages are tied to the plot and communicated verbally, positive messages are associated with subtle visual portrayals. PMID:21188281

  9. Secure Web-Site Access with Tickets and Message-Dependent Digests

    USGS Publications Warehouse

    Donato, David I.

    2008-01-01

    Although there are various methods for restricting access to documents stored on a World Wide Web (WWW) site (a Web site), none of the widely used methods is completely suitable for restricting access to Web applications hosted on an otherwise publicly accessible Web site. A new technique, however, provides a mix of features well suited for restricting Web-site or Web-application access to authorized users, including the following: secure user authentication, tamper-resistant sessions, simple access to user state variables by server-side applications, and clean session terminations. This technique, called message-dependent digests with tickets, or MDDT, maintains secure user sessions by passing single-use nonces (tickets) and message-dependent digests of user credentials back and forth between client and server. Appendix 2 provides a working implementation of MDDT with PHP server-side code and JavaScript client-side code.

  10. Low-Noise Band-Pass Amplifier

    NASA Technical Reports Server (NTRS)

    Kleinberg, L.

    1982-01-01

    Circuit uses standard components to overcome common limitation of JFET amplifiers. Low-noise band-pass amplifier employs JFET and operational amplifier. High gain and band-pass characteristics are achieved with suitable choice of resistances and capacitances. Circuit should find use as low-noise amplifier, for example as first stage instrumentation systems.

  11. PASS--Placement/Advisement for Student Success.

    ERIC Educational Resources Information Center

    Shreve, Chuck; Wildie, Avace

    In 1985-86, Northern Michigan College (NMC) used funds received from the United States Department of Education to develop a system of assessment, advisement, and placement--Placement/Advisement for Student Success (PASS), an integrated system designed to improve student retention. PASS currently consists of three components: summer orientation,…

  12. Multifrequency, single pass free electron laser

    DOEpatents

    Szoke, Abraham; Prosnitz, Donald

    1985-01-01

    A method for simultaneous amplification of laser beams with a sequence of frequencies in a single pass, using a relativistic beam of electrons grouped in a sequence of energies corresponding to the sequence of laser beam frequencies. The method allows electrons to pass from one potential well or "bucket" to another adjacent bucket, thus increasing efficiency of trapping and energy conversion.

  13. Pass transistor implementations of multivalued logic

    NASA Technical Reports Server (NTRS)

    Maki, G.; Whitaker, S.

    1990-01-01

    A simple straight-forward Karnaugh map logic design procedure for realization of multiple-valued logic circuits is presented in this paper. Pass transistor logic gates are used to realize multiple-valued networks. This work is an extension of pass transistor implementations for binary-valued logic.

  14. Learning Messages Notification System to Mobile Devices

    ERIC Educational Resources Information Center

    Jimenez, M. Lourdes

    2005-01-01

    The work presents a new method to send educational messages in e-learning systems. The communication tools are one of the main characteristics of the virtual formative actions, in addition of the contents and the evaluation. The system must help to motivate the students, mainly those who do not leave the formative action and continue it until the…

  15. Business Professionals Workplace Message Quality Perceptions

    ERIC Educational Resources Information Center

    Roach, Joy L.; Anderson, Marcia A.

    2007-01-01

    In light of today's large amount of written workplace communication, this study attempted to reveal information regarding the quality in which business messages are encoded on the job. Data were gathered through a questionnaire administered to a sample of 1994-2004 MBA graduates of three AACSB-accredited programs. Findings suggest that business…

  16. Multicultural Messages: Nonverbal Communication in the Classroom.

    ERIC Educational Resources Information Center

    Pitton, Debra; And Others

    In the drive to facilitate inclusion in the classroom, one often overlooked factor that affects the environment of all classrooms is nonverbal interaction. This study was conducted to identify some specific nonverbal messages that are often culturally bound; to help educators and others involved in education understand nonverbal signals and avoid…

  17. Princess Picture Books: Content and Messages

    ERIC Educational Resources Information Center

    Dale, Lourdes P.; Higgins, Brittany E.; Pinkerton, Nick; Couto, Michelle; Mansolillo, Victoria; Weisinger, Nica; Flores, Marci

    2016-01-01

    Because many girls develop their understanding of what it means to be a girl from books about princesses, the researchers coded the messages and content in 58 princess books (picture, fairy tales, and fractured fairy tales). Results indicate that gender stereotypes are present in the books--the princesses were more likely to be nurturing, in…

  18. The Effects of Dogmatism on Message Formulation.

    ERIC Educational Resources Information Center

    Smith, Craig Allen

    This paper presents two research studies on the use of dogmatism as a predictor of verbal communication behavior. The studies examined the effects of dogmatism on the formulation of written and oral persuasive messages by comparing college students' scores on the Rokeach D and California F Scales with a content analysis of the written or oral…

  19. Kids Paint Mural to Send Message!

    ERIC Educational Resources Information Center

    Myers, Callie; Adams, Alexis

    1994-01-01

    Describes the efforts of a group called Teens Networking Together (TNT) to paint a mural and send a message to their neighbors about taking care of the environment and taking pride in their cultural history. The teens focused on the importance of clean water and waste disposal issues. (LZ)

  20. Creating an Instant Messaging Reference System.

    ERIC Educational Resources Information Center

    Fagan, Jody Condit; Calloway, Michele

    2001-01-01

    Discussion of library digital reference services focuses on the features of instant messaging reference systems and the in-house development of a system that incorporates them at Southern Illinois University at Carbondale. Summarizes and evaluates library chat system features and compares commercial software that is available. (Author/LRW)

  1. Type of Message and Attitude Change.

    ERIC Educational Resources Information Center

    Edwards, John; Smith-Bandy, Kerry

    A study compared people's reactions to different types of assertions concerning social issues. For purposes of the study, assertion was defined as having three components: a reference to the issue itself, an attribute having evaluative implications and a verb phrase linking the issue with the attribute. Eight types of messages were composed…

  2. Message Integrity Model for Wireless Sensor Networks

    ERIC Educational Resources Information Center

    Qleibo, Haider W.

    2009-01-01

    WSNs are susceptible to a variety of attacks. These attacks vary in the way they are performed and executed; they include but not limited to node capture, physical tampering, denial of service, and message alteration. It is of paramount importance to protect gathered data by WSNs and defend the network against illegal access and malicious…

  3. Further Conceptualization of Explanation in Negative Messages.

    ERIC Educational Resources Information Center

    Limaye, Mohan R.

    1997-01-01

    Makes two suggestions for presentation in the classroom and in textbooks of business communication regarding explanation in negative messages: (1) providing a reasonable explanation is the sender's moral obligation, and receiving such explanation is a natural right of the target; and (2) explanation should be presented on two levels: general and…

  4. 47 CFR 80.95 - Message charges.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Message charges. 80.95 Section 80.95... charges. (a) Except as specified in § 20.15(c) of this chapter with respect to commercial mobile radio service providers, charges must not be made for service of: (1) Any public coast station unless...

  5. 47 CFR 80.95 - Message charges.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Message charges. 80.95 Section 80.95... charges. (a) Except as specified in § 20.15(c) of this chapter with respect to commercial mobile radio service providers, charges must not be made for service of: (1) Any public coast station unless...

  6. Instant Messaging Reference: How Does It Compare?

    ERIC Educational Resources Information Center

    Desai, Christina M.

    2003-01-01

    Compares a digital reference service that uses instant messaging with traditional, face-to-face reference based on experiences at the Southern Illinois University library. Addresses differences in reference questions asked, changes in the reference transaction, student expectations, bibliographic instruction, and librarian attitudes and procedures…

  7. An approach for message exchange using archetypes.

    PubMed

    Moraes, João L C; Souza, Wanderley L; Cavalini, Luciana T; Pires, Luís F; Prado, Antonio F

    2013-01-01

    The application of ICT on the whole range of health sector activities, known as e-health, can simplify the access to health care services and will only be acceptable for realistic scenarios if it supports efficient information exchange amongst the caregivers and their patients. The aim of this paper is present an approach for message exchange to realistic scenarios. PMID:23920910

  8. Procedural Messages in Small Group Interaction.

    ERIC Educational Resources Information Center

    Putnam, Linda L.

    Three studies were conducted to ascertain the relationship between predisposition for group work climate and the types of procedural messages that group members employ. In the studies, expectations about group work procedures fell into two categories: high procedural order (HPO) and low procedural order (LPO). Each category consisted of four…

  9. Educational Messages in Tevfik Fikret's Poems

    ERIC Educational Resources Information Center

    Erdal, Kelime

    2011-01-01

    Being in the education community for long years, Tevfik Fikret aims to educate children and teenagers with the works he has written while he is carrying out his profession. Knowing child's world very well, the poet gives messages which can be counted valid in today's education perception. Emphasizing the basic humanistic and moral values such as…

  10. Risk-based scheduling of multiple search passes for UUVs

    NASA Astrophysics Data System (ADS)

    Baylog, John G.; Wettergren, Thomas A.

    2016-05-01

    This paper addresses selected computational aspects of collaborative search planning when multiple search agents seek to find hidden objects (i.e. mines) in operating environments where the detection process is prone to false alarms. A Receiver Operator Characteristic (ROC) analysis is applied to construct a Bayesian cost objective function that weighs and combines missed detection and false alarm probabilities. It is shown that for fixed ROC operating points and a validation criterion consisting of a prerequisite number of detection outcomes, an interval exists in the number of conducted search passes over which the risk objective function is supermodular. We show that this property is not retained beyond validation criterion boundaries. We investigate the use of greedy algorithms for distributing search effort and, in particular, examine the double greedy algorithm for its applicability under conditions of varying criteria. Numerical results are provided to demonstrate the effectiveness of the approach.

  11. Middleware for Processing Message Queues with Elasticity Support and Sequential Integrity of Asynchronous Message Processing

    NASA Astrophysics Data System (ADS)

    Henrique Teixeira, Eduardo; Patrícia Favacho de Araújo, Aletéia

    2015-10-01

    Elasticity in computing refers to dynamically adjusting the amount of allocated resources to process a distributed application. In order to achieve this, mechanisms are needed to avoid the phenomenon of the elasticity threshold detection moving constantly up or down. The existing work fails to deliver sequential integrity of asynchronous messages processing and the asymmetries of data distribution to achieve parallel consumption. This paper fills this gaps and proposes a middleware solution to dynamically analyze the flow of message queue, and a mechanism to increase the parallelized consumption based on the output behavior. An architecture for IOD (Increase On Demand) middleware is presented, with support for the increase and decrease of thread's to cope with the growth of message queues, using the technique of limit-based heuristics over a given period of time and grouping messages into sub-queues based on classification criteria.

  12. Assessing prosocial message effectiveness: effects of message quality, production quality, and persuasiveness.

    PubMed

    Austin, E W; Pinkleton, B; Fujioka, Y

    1999-01-01

    The purpose of this study was to determine whether the effectiveness of prosocial messages is compromised by poor design. A receiver-oriented content analysis (N = 246) was used to assess college students' perceptions of the message quality, production quality, and persuasiveness of advertisements and prosocial advertisements regarding alcohol. After providing background information, respondents rated a series of video clips on a variety of criteria guided by the Message Interpretation Process (MIP) model. Results indicated that prosocial advertisements were rated as higher in quality than were commercial advertisements overall and on logic-based criteria, but prosocial advertisements nevertheless had weaker relationships to viewers' beliefs and reported behaviors relevant to drinking alcohol. Heavier drinkers rated commercial advertisements more positively than did lighter/nondrinkers. They were less skeptical of persuasive messages and rated prosocial advertisements lower in effectiveness and commercial advertisements higher in effectiveness. PMID:10977288

  13. An improved coarse-grained parallel algorithm for computational acceleration of ordinary Kriging interpolation

    NASA Astrophysics Data System (ADS)

    Hu, Hongda; Shu, Hong

    2015-05-01

    Heavy computation limits the use of Kriging interpolation methods in many real-time applications, especially with the ever-increasing problem size. Many researchers have realized that parallel processing techniques are critical to fully exploit computational resources and feasibly solve computation-intensive problems like Kriging. Much research has addressed the parallelization of traditional approach to Kriging, but this computation-intensive procedure may not be suitable for high-resolution interpolation of spatial data. On the basis of a more effective serial approach, we propose an improved coarse-grained parallel algorithm to accelerate ordinary Kriging interpolation. In particular, the interpolation task of each unobserved point is considered as a basic parallel unit. To reduce time complexity and memory consumption, the large right hand side matrix in the Kriging linear system is transformed and fixed at only two columns and therefore no longer directly relevant to the number of unobserved points. The MPI (Message Passing Interface) model is employed to implement our parallel programs in a homogeneous distributed memory system. Experimentally, the improved parallel algorithm performs better than the traditional one in spatial interpolation of annual average precipitation in Victoria, Australia. For example, when the number of processors is 24, the improved algorithm keeps speed-up at 20.8 while the speed-up of the traditional algorithm only reaches 9.3. Likewise, the weak scaling efficiency of the improved algorithm is nearly 90% while that of the traditional algorithm almost drops to 40% with 16 processors. Experimental results also demonstrate that the performance of the improved algorithm is enhanced by increasing the problem size.

  14. Using Publish-Subscribe Messaging for System Status and Automation

    NASA Technical Reports Server (NTRS)

    Smith, Danford S.

    2015-01-01

    The NASA Goddard Mission Services Evolution Center (GMSEC) system is a message-based plug-and-play open system architecture used in many of NASA mission operations centers. This presentation will focus on the use of GMSEC standard messages to report and analyze the status of a system and enable the automation of the system's components. In GMSEC systems, each component reports its status using a keep-alive message and also publishes status and activities as log messages. In addition, the components can accept functional directive messages from the GMSEC message bus. Over the past several years, development teams have found ways to utilize these messages to create innovative display pages and increasingly sophisticated approaches to automation. This presentation will show the flexibility and value of the message-based approach to system awareness and automation.

  15. Effects of Instant Messaging on School Performance in Adolescents.

    PubMed

    Grover, Karan; Pecor, Keith; Malkowski, Michael; Kang, Lilia; Machado, Sasha; Lulla, Roshni; Heisey, David; Ming, Xue

    2016-06-01

    Instant messaging may compromise sleep quality and school performance in adolescents. We aimed to determine associations between nighttime messaging and daytime sleepiness, self-reported sleep parameters, and/or school performance. Students from 3 high schools in New Jersey completed anonymous questionnaires assessing sleep duration, daytime sleepiness, messaging habits, and academic performance. Of the 2,352 students sampled, 1,537 responses were contrasted among grades, sexes, and messaging duration, both before and after lights out. Students who reported longer duration of messaging after lights out were more likely to report a shorter sleep duration, higher rate of daytime sleepiness, and poorer academic performance. Messaging before lights out was not associated with higher rates of daytime sleepiness or poorer academic performance. Females reported more messaging, more daytime sleepiness, and better academic performance than males. There may be an association between text messaging and school performance in this cohort of students. PMID:26762509

  16. Effects of Verbal-Vocal Message Discrepancy on Teacher Credibility.

    ERIC Educational Resources Information Center

    Karr, P. J.; Beatty, Michael

    1979-01-01

    Vocal cues which were inconsistent with verbal messages and their effects on teacher credibility were examined. Results suggested that teacher credibility was at least partially dependent upon the degree of verbal vocal consistency in teachers' messages. (Author/MH)

  17. Preventing messaging queue deadlocks in a DMA environment

    DOEpatents

    Blocksome, Michael A; Chen, Dong; Gooding, Thomas; Heidelberger, Philip; Parker, Jeff

    2014-01-14

    Embodiments of the invention may be used to manage message queues in a parallel computing environment to prevent message queue deadlock. A direct memory access controller of a compute node may determine when a messaging queue is full. In response, the DMA may generate and interrupt. An interrupt handler may stop the DMA and swap all descriptors from the full messaging queue into a larger queue (or enlarge the original queue). The interrupt handler then restarts the DMA. Alternatively, the interrupt handler stops the DMA, allocates a memory block to hold queue data, and then moves descriptors from the full messaging queue into the allocated memory block. The interrupt handler then restarts the DMA. During a normal messaging advance cycle, a messaging manager attempts to inject the descriptors in the memory block into other messaging queues until the descriptors have all been processed.

  18. 14 CFR 189.3 - Kinds of messages accepted or relayed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... communication systems any messages concerning international or overseas aircraft operations described in... address: (1) Distress messages and distress traffic. (2) Messages concerning the safety of human life....

  19. Developing a Pass 8 Cosmic-Ray Proton Event Class

    NASA Astrophysics Data System (ADS)

    Green, David M.; Hays, Elizabeth A.; Fermi Large Area Telescope Collaboration

    2015-04-01

    The Pass 8 improved gamma-ray simulation and reconstruction package for the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope has drastically enhanced the ability of the LAT to perform gamma-ray science. The Pass 8 improvements have also allowed for the development of a new cosmic-ray proton analysis. Using these new algorithms, we are able to create a proton event class which can be used for future studies, including spectral and anisotropy analyses. This developing event selection has a high acceptance with energies from 50 GeV to over 1 TeV and, with over 6 years of data, will give high statistics for future analyses. Currently, energy reconstruction and systematic errors in the acceptance are being investigated. A future anisotropy study is of interest because of less dependence on these factors than a spectral analysis. We present a detailed study of this new proton event class for the Pass 8 proton analysis.

  20. The Message Reporting System in the ATLAS DAQ System

    NASA Astrophysics Data System (ADS)

    Caprini, M.; Fedorko, I.; Kolos, S.

    2008-06-01

    The Message Reporting System (MRS) in the ATLAS data acquisition system (DAQ) is one package of the Online Software which acts as a glue of various elements of DAQ, High Level Trigger (HLT) and Detector Control System (DCS). The aim of the MRS is to provide a facility which allows all software components in ATLAS to report messages to other components of the distributed DAQ system. The processes requiring a MRS are on one hand applications that report error conditions or information and on the other hand message processors that receive reported messages. A message reporting application can inject one or more messages into the MRS at any time. An application wishing to receive messages can subscribe to a message group according to defined criteria. The application receives messages that fulfill the subscription criteria when they are reported to MRS. The receiver message processing can consist of anything from simply logging the messages in a file/terminal to performing message analysis. The inter-process communication is achieved using the CORBA technology. The design, architecture and the used technology of MRS are reviewed in this paper.

  1. Lol: New Language and Spelling in Instant Messaging

    ERIC Educational Resources Information Center

    Varnhagen, Connie K.; McFall, G. Peggy; Pugh, Nicole; Routledge, Lisa; Sumida-MacDonald, Heather; Kwong, Trudy E.

    2010-01-01

    Written communication in instant messaging, text messaging, chat, and other forms of electronic communication appears to have generated a "new language" of abbreviations, acronyms, word combinations, and punctuation. In this naturalistic study, adolescents collected their instant messaging conversations for a 1-week period and then completed a…

  2. 47 CFR 11.44 - EAS message priorities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false EAS message priorities. 11.44 Section 11.44 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EMERGENCY ALERT SYSTEM (EAS) Organization § 11.44 EAS message priorities. (a) A national activation of the EAS for a Presidential message with the Event...

  3. 47 CFR 11.44 - EAS message priorities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false EAS message priorities. 11.44 Section 11.44 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EMERGENCY ALERT SYSTEM (EAS) Organization § 11.44 EAS message priorities. (a) A national activation of the EAS for a Presidential message with the Event...

  4. Potential Nutrition Messages in Magazines Read by College Students.

    ERIC Educational Resources Information Center

    Hertzler, Ann A.; Grun, Ingolf

    1990-01-01

    Surveyed advertisements in magazines read by college students in nutrition class for hidden food and nutrition messages. Hidden messages for females could imply beauty through fashion products, beauty aids, and supplements but with nutrition slimming plan. Males may be receiving subtle message that food choices do not matter and that alcohol and…

  5. Teaching Students the Persuasive Message through Small Group Activity

    ERIC Educational Resources Information Center

    Creelman, Valerie

    2008-01-01

    Teaching students to write persuasive messages is a critical feature of any undergraduate business communications course. For the persuasive writing module in the author's course, students write a persuasive message on the basis of the four-part indirect pattern often used for sales or fund-raising messages. The course text she uses identifies…

  6. Internet and Mobile Phone Text Messaging Intervention for College Smokers

    ERIC Educational Resources Information Center

    Riley, William; Obermayer, Jami; Jean-Mary, Jersino

    2008-01-01

    Objective: The authors developed a smoking cessation program using mobile phone text messaging to provide tailored and stage-specific messages to college smokers. Participants and Methods: The authors recruited 31 daily smokers who desired to quit from a college campus and asked them to use an Internet and mobile phone text messaging program to…

  7. Information Networks: A Probablistic Model for Hierarchical Message Transfer.

    ERIC Educational Resources Information Center

    Bhat, U. Narayan; And Others

    A strictly hierarchical message transfer scheme requires that a message follow a specified referral path unless finally it is either rejected or filled at any one of the information centers of the network. Thus at each node in the network three decisions can be made: satisfy, reject or refer the message to the succeeding node in the hierarchy.…

  8. Using Text-Messaging in the Secondary Classroom

    ERIC Educational Resources Information Center

    Thomas, Kevin; Orthober, Corrie

    2011-01-01

    To examine the potential uses of and barriers to text-messaging in secondary schools, three classes (66 students) of high school students used their personal mobile phones to receive out of school, course-related text-messages from teachers. Forty-six students (70%) agreed to receive text-messages. Findings indicate that participants found…

  9. Message Efficient Checkpointing and Rollback Recovery in Heterogeneous Mobile Networks

    NASA Astrophysics Data System (ADS)

    Jaggi, Parmeet Kaur; Singh, Awadhesh Kumar

    2016-06-01

    Heterogeneous networks provide an appealing way of expanding the computing capability of mobile networks by combining infrastructure-less mobile ad-hoc networks with the infrastructure-based cellular mobile networks. The nodes in such a network range from low-power nodes to macro base stations and thus, vary greatly in their capabilities such as computation power and battery power. The nodes are susceptible to different types of transient and permanent failures and therefore, the algorithms designed for such networks need to be fault-tolerant. The article presents a checkpointing algorithm for the rollback recovery of mobile hosts in a heterogeneous mobile network. Checkpointing is a well established approach to provide fault tolerance in static and cellular mobile distributed systems. However, the use of checkpointing for fault tolerance in a heterogeneous environment remains to be explored. The proposed protocol is based on the results of zigzag paths and zigzag cycles by Netzer-Xu. Considering the heterogeneity prevalent in the network, an uncoordinated checkpointing technique is employed. Yet, useless checkpoints are avoided without causing a high message overhead.

  10. Content analysis of antismoking videos on YouTube: message sensation value, message appeals, and their relationships with viewer responses.

    PubMed

    Paek, Hye-Jin; Kim, Kyongseok; Hove, Thomas

    2010-12-01

    Focusing on several message features that are prominent in antismoking campaign literature, this content-analytic study examines 934 antismoking video clips on YouTube for the following characteristics: message sensation value (MSV) and three types of message appeal (threat, social and humor). These four characteristics are then linked to YouTube's interactive audience response mechanisms (number of viewers, viewer ratings and number of comments) to capture message reach, viewer preference and viewer engagement. The findings suggest the following: (i) antismoking messages are prevalent on YouTube, (ii) MSV levels of online antismoking videos are relatively low compared with MSV levels of televised antismoking messages, (iii) threat appeals are the videos' predominant message strategy and (iv) message characteristics are related to viewer reach and viewer preference. PMID:20923913

  11. Hurricane Sandy -- Pass 1, Oct. 29, 2012

    NASA Video Gallery

    Hurricane Sandy was viewed Monday morning from the International Space Station as it orbited 260 miles above the Atlantic Ocean. Sandy had sustained winds of 90 miles an hour as the station passed ...

  12. Automated Procedure for Roll Pass Design

    NASA Astrophysics Data System (ADS)

    Lambiase, F.; Langella, A.

    2009-04-01

    The aim of this work has been to develop an automatic roll pass design method, capable of minimizing the number of roll passes. The adoption of artificial intelligence technologies, particularly expert systems, and a hybrid model for the surface profile evaluation of rolled bars, has allowed us to model the search for the minimal sequence with a tree path search. This approach permitted a geometrical optimization of roll passes while allowing automation of the roll pass design process. Moreover, the heuristic nature of the inferential engine contributes a great deal toward reducing search time, thus allowing such a system to be employed for industrial purposes. Finally, this new approach was compared with other recently developed automatic systems to validate and measure possible improvements among them.

  13. Text Messaging for Addiction: A Review

    PubMed Central

    Keoleian, Victoria; Polcin, Douglas; Galloway, Gantt P.

    2015-01-01

    Individuals seeking treatment for addiction often experience barriers due to cost, lack of local treatment resources, or either school or work schedule conflicts. Text messaging-based addiction treatment is inexpensive and has the potential to be widely accessible in real time. We conducted a comprehensive literature review identifying 11 published randomized controlled trials (RCTs) evaluating text messaging-based interventions for tobacco smoking, 4 studies for reducing alcohol consumption, 1 pilot study in former methamphetamine (MA) users, and 1 study based on qualitative interviews with cannabis users. Abstinence outcome results in RCTs of smokers willing to make a quit attempt have been positive overall in the short term and as far out as at 6 and 12 months. Studies aimed at reducing alcohol consumption have been promising. More data are needed to evaluate the feasibility, acceptability, and efficacy of this approach for other substance use problems. PMID:25950596

  14. Mobile text messaging solutions for obesity prevention

    NASA Astrophysics Data System (ADS)

    Akopian, David; Jayaram, Varun; Aaleswara, Lakshmipathi; Esfahanian, Moosa; Mojica, Cynthia; Parra-Medina, Deborah; Kaghyan, Sahak

    2011-02-01

    Cellular telephony has become a bright example of co-evolution of human society and information technology. This trend has also been reflected in health care and health promotion projects which included cell phones in data collection and communication chain. While many successful projects have been realized, the review of phone-based data collection techniques reveals that the existing technologies do not completely address health promotion research needs. The paper presents approaches which close this gap by extending existing versatile platforms. The messaging systems are designed for a health-promotion research to prevent obesity and obesity-related health disparities among low-income Latino adolescent girls. Messaging and polling mechanisms are used to communicate and automatically process response data for the target constituency. Preliminary survey data provide an insight on phone availability and technology perception for the study group.

  15. Ritual, meaningfulness, and interstellar message construction

    NASA Astrophysics Data System (ADS)

    Traphagan, John W.

    2010-10-01

    In this paper, I am interested in exploring the potential of ritual performance as a means of communication with ETI. I argue that the study of ritual and ritualized behavior, understood as a technique for representation of meaning and meaningfulness about the world, has potential to inform how scientists think about the construction and interpretation of interstellar messages. I do not suggest that ritual activities themselves provide more than limited potential for communication with ETI. However, the structural elements of ritual and the manner in which meaning is conveyed through the formality and repetition of ritual is at least to some extent decipherable cross-culturally and provides one way to think about how to express important aspects of humans and their cultures to ETI and to represent, if not specific meanings themselves, the fact that a message is meaningful.

  16. Text messaging for addiction: a review.

    PubMed

    Keoleian, Victoria; Polcin, Douglas; Galloway, Gantt P

    2015-01-01

    Individuals seeking treatment for addiction often experience barriers due to cost, lack of local treatment resources, or either school or work schedule conflicts. Text-messaging-based addiction treatment is inexpensive and has the potential to be widely accessible in real time. We conducted a comprehensive literature review identifying 11 published, randomized controlled trials (RCTs) evaluating text-messaging-based interventions for tobacco smoking, four studies for reducing alcohol consumption, one pilot study in former methamphetamine (MA) users, and one study based on qualitative interviews with cannabis users. Abstinence outcome results in RCTs of smokers willing to make a quit attempt have been positive overall in the short term and as far out as at six and 12 months. Studies aimed at reducing alcohol consumption have been promising. More data are needed to evaluate the feasibility, acceptability, and efficacy of this approach for other substance use problems. PMID:25950596

  17. The perfect message at the perfect moment.

    PubMed

    Kalyanam, Kirthi; Zweben, Monte

    2005-11-01

    Marketers planning promotional campaigns ask questions to boost the odds that the messages will be accepted: Who should receive each message? What should be its content? How should we deliver it? The one question they rarely ask is, when should we deliver it? That's too bad, because in marketing, timing is arguably the most important variable of all. Indeed, there are moments in a customer's relationship with a business when she wants to communicate with that business because something has changed. If the company contacts her with the right message in the right format at the right time, there's a good chance of a warm reception. The question of "when" can be answered by a new computer-based model called "dialogue marketing," which is, to date, the highest rung on an evolutionary ladder that ascends from database marketing to relationship marketing to one-to-one marketing. Its principle advantages over older approaches are that it is completely interactive, exploits many communication channels, and is "relationship aware": that is, it continuously tracks every nuance of the customer's interaction with the business. Thus, dialogue marketing responds to each transition in that relationship at the moment the customer requires attention. Turning a traditional marketing strategy into a dialogue-marketing program is a straightforward matter. Begin by identifying the batch communications you make with customers, then ask yourself what events could trigger those communications to make them more timely. Add a question or call to action to each message and prepare a different treatment or response for each possible answer. Finally, create a series of increasingly urgent calls to action that kick in if the question or call to action goes unanswered by the customer. As dialogue marketing proliferates, it may provide the solid new footing that Madison Avenue seeks. PMID:16299965

  18. Washington Commentary: Spinning the Message on NCLB

    ERIC Educational Resources Information Center

    Lewis, Anne C.

    2004-01-01

    This column is about a city with two tales--one of spin and the other of sputter. No matter who occupies the White House for the next four years, the past four have borne witness to some of the most ludicrous uses of taxpayer money ever, as the U.S. Department of Education (ED) has tried to spin its message on No Child Left Behind (NCLB) across…

  19. The Physical Therapy and Society Summit (PASS) Meeting: observations and opportunities.

    PubMed

    Kigin, Colleen M; Rodgers, Mary M; Wolf, Steven L

    2010-11-01

    The construct of delivering high-quality and cost-effective health care is in flux, and the profession must strategically plan how to meet the needs of society. In 2006, the House of Delegates of the American Physical Therapy Association passed a motion to convene a summit on "how physical therapists can meet current, evolving, and future societal health care needs." The Physical Therapy and Society Summit (PASS) meeting on February 27-28, 2009, in Leesburg, Virginia, sent a clear message that for physical therapists to be effective and thrive in the health care environment of the future, a paradigm shift is required. During the PASS meeting, participants reframed our traditional focus on the physical therapist and the patient/client (consumer) to one in which physical therapists are an integral part of a collaborative, multidisciplinary health care team with the health care consumer as its focus. The PASS Steering Committee recognized that some of the opportunities that surfaced during the PASS meeting may be disruptive or may not be within the profession's present strategic or tactical plans. Thus, adopting a framework that helps to establish the need for change that is provocative and potentially disruptive to our present care delivery, yet prioritizes opportunities, is a critical and essential step. Each of us in the physical therapy profession must take on post-PASS roles and responsibilities to accomplish the systemic change that is so intimately intertwined with our destiny. This article offers a perspective of the dynamic dialogue and suggestions that emerged from the PASS event, providing further opportunities for discussion and action within our profession. PMID:20829448

  20. Audience readings of media messages about MRSA.

    PubMed

    Washer, P; Joffe, H; Solberg, C

    2008-09-01

    This paper explores whether, and to what extent, national newspaper messages tally with public perceptions about meticillin-resistant Staphylococcus aureus (MRSA). It compares research on media messages about MRSA with interview data gathered from a demographically diverse sample of 60 people interviewed from the Greater London area. Across the interview sample there was a shared consensus that most people associated MRSA not with the history of antibiotic use, but with dirty and poorly managed hospitals. Some media messages, such as blaming MRSA on the alleged 'management culture' of the NHS, seemed to capture the Zeitgeist, whereas others, in particular the 'celebrity victims' of MRSA, did not seem to resonate with the audience. This study also found that ideas based on scientific understandings about germ theory and the immune system were held alongside folklore such as miasmic theory. The comparison of media and mind thus points to the existence of pre-scientific understandings of germs, contagion and blame in parallel with the biomedical story in the minds of the public. The findings contribute to our understanding of the public and patients' views of this infection. PMID:18621438

  1. Low latency messages on distributed memory multiprocessors

    NASA Technical Reports Server (NTRS)

    Rosing, Matthew; Saltz, Joel

    1993-01-01

    Many of the issues in developing an efficient interface for communication on distributed memory machines are described and a portable interface is proposed. Although the hardware component of message latency is less than one microsecond on many distributed memory machines, the software latency associated with sending and receiving typed messages is on the order of 50 microseconds. The reason for this imbalance is that the software interface does not match the hardware. By changing the interface to match the hardware more closely, applications with fine grained communication can be put on these machines. Based on several tests that were run on the iPSC/860, an interface that will better match current distributed memory machines is proposed. The model used in the proposed interface consists of a computation processor and a communication processor on each node. Communication between these processors and other nodes in the system is done through a buffered network. Information that is transmitted is either data or procedures to be executed on the remote processor. The dual processor system is better suited for efficiently handling asynchronous communications compared to a single processor system. The ability to send data or procedure is very flexible for minimizing message latency, based on the type of communication being performed. The test performed and the proposed interface are described.

  2. Crowdsourced Peer- Versus Expert-Written Smoking-Cessation Messages

    PubMed Central

    Coley, Heather L.; Sadasivam, Rajani S.; Williams, Jessica H.; Volkman, Julie E.; Schoenberger, Yu-Mei; Kohler, Connie; Sobko, Heather; Ray, Midge N.; Allison, Jeroan J.; Epi, MS; Ford, Daniel E.; Gilbert, Gregg H.; Houston, Thomas K.

    2013-01-01

    Background Tailored, web-assisted interventions can reach many smokers. Content from other smokers (peers) through crowdsourcing could enhance relevance. Purpose To evaluate whether peers can generate tailored messages encouraging other smokers to use a web-assisted tobacco intervention (Decide2Quit.org). Methods Phase 1: In 2009, smokers wrote messages in response to scenarios for peer advice. These smoker-to-smoker (S2S) messages were coded to identify themes. Phase 2: resulting S2S messages, and comparison expert messages, were then emailed to newly registered smokers. In 2012, subsequent Decide2Quit.org visits following S2S or expert-written e-mails were compared. Results Phase 1: a total of 39 smokers produced 2886 messages (message themes: attitudes and expectations, improvements in quality of life, seeking help, and behavioral strategies). For not-ready-to-quit scenarios, S2S messages focused more on expectations around a quit attempt and how quitting would change an individual’s quality of life. In contrast, for ready-to-quit scenarios, S2S messages focused on behavioral strategies for quitting. Phase 2: In multivariable analysis, S2S messages were more likely to generate a return visit (OR=2.03, 95% CI=1.74, 2.35), compared to expert messages. A significant effect modification of this association was found, by time-from-registration and message codes (both interaction terms p<0.01). In stratified analyses, S2S codes that were related more to “social” and “real-life” aspects of smoking were driving the main association of S2S and increased return visits. Conclusions S2S peer messages that increased longitudinal engagement in a web-assisted tobacco intervention were successfully collected and delivered. S2S messages expanded beyond the biomedical model to enhance relevance of messages. PMID:24139766

  3. A Personalized Automated Messaging System to Improve Adherence to Prostate Cancer Screening: Research Protocol

    PubMed Central

    2012-01-01

    Background Public adherence to cancer screening guidelines is poor. Patient confusion over multiple recommendations and modalities for cancer screening has been found to be a major barrier to screening adherence. Such problems will only increase as screening guidelines and timetables become individualized. Objective We propose to increase compliance with cancer screening through two-way rich media mobile messaging based on personalized risk assessment. Methods We propose to develop and test a product that will store algorithms required to personalize cancer screening in a central database managed by a rule-based workflow engine, and implemented via messaging to the patient’s mobile phone. We will conduct a randomized controlled trial focusing on prostate cancer screening to study the hypothesis that mobile reminders improve adherence to screening guidelines. We will also explore a secondary hypothesis that patients who reply to the messaging reminders are more engaged and at lower risk of non-adherence. We will conduct a randomized controlled trial in a sample of males between 40 and 75 years (eligible for prostate cancer screening) who are willing to receive text messages, email, or automated voice messages. Participants will be recruited from a primary care clinic and asked to schedule prostate cancer screening at the clinic within the next 3 weeks. The intervention group will receive reminders and confirmation communications for making an appointment, keeping the appointment, and reporting the test results back to the investigators. Three outcomes will be evaluated: (1) the proportion of participants who make an appointment with a physician following a mobile message reminder, (2) the proportion of participants who keep the appointment, and (3) the proportion of participants who report the results of the screening (via text or Web). Results This is an ongoing project, supported by by a small business commercialization grant from the National Center for

  4. Source Similarity and Social Media Health Messages: Extending Construal Level Theory to Message Sources.

    PubMed

    Young, Rachel

    2015-09-01

    Social media users post messages about health goals and behaviors to online social networks. Compared with more traditional sources of health communication such as physicians or health journalists, peer sources are likely to be perceived as more socially close or similar, which influences how messages are processed. This experimental study uses construal level theory of psychological distance to predict how mediated health messages from peers influence health-related cognition and behavioral intention. Participants were exposed to source cues that identified peer sources as being either highly attitudinally and demographically similar to or different from participants. As predicted by construal level theory, participants who perceived sources of social media health messages as highly similar listed a greater proportion of beliefs about the feasibility of health behaviors and a greater proportion of negative beliefs, while participants who perceived sources as more dissimilar listed a greater proportion of positive beliefs about the health behaviors. Results of the study could be useful in determining how health messages from peers could encourage individuals to set realistic health goals. PMID:26348816

  5. The message development tool: a case for effective operationalization of messaging in social marketing practice.

    PubMed

    Mattson, Marifran; Basu, Ambar

    2010-07-01

    That messages are essential, if not the most critical component of any communicative process, seems like an obvious claim. More so when the communication is about health--one of the most vital and elemental of human experiences (Babrow & Mattson, 2003). Any communication campaign that aims to change a target audience's health behaviors needs to centralize messages. Even though messaging strategies are an essential component of social marketing and are a widely used campaign model, health campaigns based on this framework have not always been able to effectively operationalize this key component, leading to cases where initiating and sustaining prescribed health behavior has been difficult (MacStravic, 2000). Based on an examination of the VERB campaign and an Australian breastfeeding promotion campaign, we propose a message development tool within the ambit of the social marketing framework that aims to extend the framework and ensure that the messaging component of the model is contextualized at the core of planning, implementation, and evaluation efforts. PMID:20706895

  6. Quantum messages with signatures forgeable in arbitrated quantum signature schemes

    NASA Astrophysics Data System (ADS)

    Kim, Taewan; Choi, Jeong Woon; Jho, Nam-Su; Lee, Soojoon

    2015-02-01

    Even though a method to perfectly sign quantum messages has not been known, the arbitrated quantum signature scheme has been considered as one of the good candidates. However, its forgery problem has been an obstacle to the scheme becoming a successful method. In this paper, we consider one situation, which is slightly different from the forgery problem, that we use to check whether at least one quantum message with signature can be forged in a given scheme, although all the messages cannot be forged. If there are only a finite number of forgeable quantum messages in the scheme, then the scheme can be secured against the forgery attack by not sending forgeable quantum messages, and so our situation does not directly imply that we check whether the scheme is secure against the attack. However, if users run a given scheme without any consideration of forgeable quantum messages, then a sender might transmit such forgeable messages to a receiver and in such a case an attacker can forge the messages if the attacker knows them. Thus it is important and necessary to look into forgeable quantum messages. We show here that there always exists such a forgeable quantum message-signature pair for every known scheme with quantum encryption and rotation, and numerically show that there are no forgeable quantum message-signature pairs that exist in an arbitrated quantum signature scheme.

  7. Collective Influence Algorithm to find influencers via optimal percolation in massively large social media.

    PubMed

    Morone, Flaviano; Min, Byungjoon; Bo, Lin; Mari, Romain; Makse, Hernán A

    2016-01-01

    We elaborate on a linear-time implementation of Collective-Influence (CI) algorithm introduced by Morone, Makse, Nature 524, 65 (2015) to find the minimal set of influencers in networks via optimal percolation. The computational complexity of CI is O(N log N) when removing nodes one-by-one, made possible through an appropriate data structure to process CI. We introduce two Belief-Propagation (BP) variants of CI that consider global optimization via message-passing: CI propagation (CIP) and Collective-Immunization-Belief-Propagation algorithm (CIBP) based on optimal immunization. Both identify a slightly smaller fraction of influencers than CI and, remarkably, reproduce the exact analytical optimal percolation threshold obtained in Random Struct. Alg. 21, 397 (2002) for cubic random regular graphs, leaving little room for improvement for random graphs. However, the small augmented performance comes at the expense of increasing running time to O(N(2)), rendering BP prohibitive for modern-day big-data. For instance, for big-data social networks of 200 million users (e.g., Twitter users sending 500 million tweets/day), CI finds influencers in 2.5 hours on a single CPU, while all BP algorithms (CIP, CIBP and BDP) would take more than 3,000 years to accomplish the same task. PMID:27455878

  8. Collective Influence Algorithm to find influencers via optimal percolation in massively large social media

    PubMed Central

    Morone, Flaviano; Min, Byungjoon; Bo, Lin; Mari, Romain; Makse, Hernán A.

    2016-01-01

    We elaborate on a linear-time implementation of Collective-Influence (CI) algorithm introduced by Morone, Makse, Nature 524, 65 (2015) to find the minimal set of influencers in networks via optimal percolation. The computational complexity of CI is O(N log N) when removing nodes one-by-one, made possible through an appropriate data structure to process CI. We introduce two Belief-Propagation (BP) variants of CI that consider global optimization via message-passing: CI propagation (CIP) and Collective-Immunization-Belief-Propagation algorithm (CIBP) based on optimal immunization. Both identify a slightly smaller fraction of influencers than CI and, remarkably, reproduce the exact analytical optimal percolation threshold obtained in Random Struct. Alg. 21, 397 (2002) for cubic random regular graphs, leaving little room for improvement for random graphs. However, the small augmented performance comes at the expense of increasing running time to O(N2), rendering BP prohibitive for modern-day big-data. For instance, for big-data social networks of 200 million users (e.g., Twitter users sending 500 million tweets/day), CI finds influencers in 2.5 hours on a single CPU, while all BP algorithms (CIP, CIBP and BDP) would take more than 3,000 years to accomplish the same task. PMID:27455878

  9. Collective Influence Algorithm to find influencers via optimal percolation in massively large social media

    NASA Astrophysics Data System (ADS)

    Morone, Flaviano; Min, Byungjoon; Bo, Lin; Mari, Romain; Makse, Hernán A.

    2016-07-01

    We elaborate on a linear-time implementation of Collective-Influence (CI) algorithm introduced by Morone, Makse, Nature 524, 65 (2015) to find the minimal set of influencers in networks via optimal percolation. The computational complexity of CI is O(N log N) when removing nodes one-by-one, made possible through an appropriate data structure to process CI. We introduce two Belief-Propagation (BP) variants of CI that consider global optimization via message-passing: CI propagation (CIP) and Collective-Immunization-Belief-Propagation algorithm (CIBP) based on optimal immunization. Both identify a slightly smaller fraction of influencers than CI and, remarkably, reproduce the exact analytical optimal percolation threshold obtained in Random Struct. Alg. 21, 397 (2002) for cubic random regular graphs, leaving little room for improvement for random graphs. However, the small augmented performance comes at the expense of increasing running time to O(N2), rendering BP prohibitive for modern-day big-data. For instance, for big-data social networks of 200 million users (e.g., Twitter users sending 500 million tweets/day), CI finds influencers in 2.5 hours on a single CPU, while all BP algorithms (CIP, CIBP and BDP) would take more than 3,000 years to accomplish the same task.

  10. Using text messaging in an undergraduate nursing course.

    PubMed

    Richardson, April; Littrell, Ofelia M; Challman, Sandra; Stein, Pamela

    2011-02-01

    Text messaging is a popular means of communication among young adults. Consequently, this mode of communication may be used to positively influence students in their academic studies. In this study, students were given the opportunity to receive text or e-mail messages regarding lecture content. Short message reminders, in the form of texts or e-mails, were used to send bite-sized course content to undergraduate nursing students. Messages included questions that would be answered in the next day's lecture or reiterated a main point presented in the previous day's lecture. Following a survey at the end of the course, text users responded positively toward this pedagogical approach and felt the use of text messaging enhanced their learning experience. E-mail users reported a short message reminder was moderately useful to their study of anatomy. These results suggest text messaging may be a valuable tool for educators as they seek to incorporate technology into the classroom. PMID:21210609

  11. Symmetrical band-pass loudspeaker systems

    NASA Astrophysics Data System (ADS)

    Matusiak, Grzegorz Piotr

    2001-12-01

    Loudspeaker systems are analyzed in a doctoral dissertation. The dissertation concerns loudspeaker systems, which are known as subwoofers or band-pass loudspeaker systems. Their advantages include: high- quality sound reproduction in the low-frequency range, small dimensions, small nonlinear distortions and the fact that they can be placed anywhere in a room or car. Band-pass loudspeaker systems are used widely in the so- called Home Theatre as well as to provide sound in cinema, theatre, concert, discotheque, opera, operetta, philharmonic and amphitheater halls, at open-air concerts, and so on. Various designs are mass-produced by a large number of manufacturers. The study covers an analysis of band-pass loudspeaker systems to which the frequency transformation, i.e. the reactance transformation, has been applied. Since this is a symmetrical transformation, amplitude frequency responses of the studied band-pass systems are also symmetrical (logarithmic scale of a frequency). As a result, the high-pass loudspeaker system design method, known as the Thiele-Small, Benson analysis, can be employed. The investigations include the formulation of band-pass system equations (fourth, sixth and eighth-order polynomials) and the subsequent derivation of relations for the calculation of system parameters. The obtained results enable the calculation of optimum designs for prescribed alignments, e.g. (Chebyshev) equal-ripple, (Butterworth) maximally flat, or quasi-maximally flat (QB). The analysis covers fourth, sixth and eighth-order symmetrical systems. Eighth-order systems have been divided into three kinds according to three ways of physical realization. The doctoral dissertation includes band-pass loudspeaker systems, which can be designed with active or passive filters or without the filter. Designed systems consist of a loudspeaker whose front of a diaphragm is loaded with a Helmholtz resonator, i.e. an enclosure with a vent, which radiates sound outwards. The back is

  12. Corpus Linguistics and the Design of a Response Message

    NASA Astrophysics Data System (ADS)

    Atwell, E.

    2002-01-01

    Most research related to SETI, the Search for Extra-Terrestrial Intelligence, is focussed on techniques for detection of possible incoming signals from extra-terrestrial intelligent sources (e.g. Turnbull et al. 1999), and algorithms for analysis of these signals to identify intelligent language-like characteristics (e.g. Elliott and Atwell 1999, 2000). However, another issue for research and debate is the nature of our response, should a signal arrive and be detected. The design of potentially the most significant communicative act in history should not be decided solely by astrophysicists; the Corpus Linguistics research community has a contribution to make to what is essentially a Corpus design and implementation project. (Vakoch 1998) advocated that the message constructed to transmit to extraterrestrials should include a broad, representative collection of perspectives rather than a single viewpoint or genre; this should strike a chord with Corpus Linguists for whom a central principle is that a corpus must be "balanced" to be representative (Meyer 2001). One idea favoured by SETI researchers is to transmit an encyclopaedia summarising human knowledge, such as the Encyclopaedia Britannica, to give ET communicators an overview and "training set" key to analysis of subsequent messages. Furthermore, this should be sent in several versions in parallel: the text; page-images, to include illustrations left out of the text-file and perhaps some sort of abstract linguistic representation of the text, using a functional or logic language (Ollongren 1999, Freudenthal 1960). The idea of "enriching" the message corpus with annotations at several levels should also strike a chord with Corpus Linguists who have long known that Natural language exhibits highly complex multi-layering sequencing, structural and functional patterns, as difficult to model as sequences and structures found in more traditional physical and biological sciences. Some corpora have been annotated with

  13. An aerosol absorption remote sensing algorithm

    NASA Astrophysics Data System (ADS)

    Zhai, P.; Winker, D. M.; Hu, Y.; Trepte, C. R.; Lucker, P. L.

    2013-12-01

    Aerosol absorption plays an important role in the climate by modulating atmospheric radiative forcing processes. Unfortunately aerosol absorption is very difficult to obtain via satellite remote sensing techniques. In this work we have built an algorithm to obtain aerosol absorption optical depth using both measurements from a passive O2 A-band spectrometer and an active lidar. The instrument protocols for these two satellite instruments are the O2 A-band spectrometer onboard the Orbiting Carbon Observatory (OCO-2) and the CALIOP onboard CALIPSO. The aerosol height and typing information is obtained from the CALIOP measurement. The aerosol extinction and absorption optical depths are then retrieved by fitting the forward model simulations to the O2 A-band spectrometer measurements. The forward model simulates the scattering and absorption of solar light at high spectral resolution in the O2 A-band region. The O2 and other gas absorption coefficients near 0.76 micron are calculated by either the line-by-line code (for instance, the Atmospheric Radiative Transfer Simulator) or the OCO2 ABSCO Look-Up-Table. The line parameters used are from the HITRAN 2008 database (http://www.cfa.harvard.edu/hitran/). The multiple light scattering by molecules, aerosols, and clouds is handled by the radiative transfer model based on the successive order of scattering method (Zhai et al, JQSRT, Vol. 111, pp. 1025-1040, 2010). The code is parallelized with Message Passing Interface (MPI) for better efficiency. The aerosol model is based on Shettle and Fenn (AFGL-TR 790214, 1979) with variant relative humidity. The vertical distribution of the aerosols and clouds will be read in from the CALIPSO product (http://www-calipso.larc.nasa.gov). The surface albedo is estimated by the continuum of the three bands of OCO2 payloads. Sensitivity study shows that the Gaussian quadrature (stream) number should be at least 12 to ensure the reflectance error is within 0.5% at the top of the atmosphere

  14. Improved multiple-pass Raman spectrometer.

    PubMed

    KC, Utsav; Silver, Joel A; Hovde, David C; Varghese, Philip L

    2011-08-20

    An improved Raman gain spectrometer for flame measurements of gas temperature and species concentrations is described. This instrument uses a multiple-pass optical cell to enhance the incident light intensity in the measurement volume. The Raman signal is 83 times larger than from a single pass, and the Raman signal-to-noise ratio (SNR) in room-temperature air of 153 is an improvement over that from a single-pass cell by a factor of 9.3 when the cell is operated with 100 passes and the signal is integrated over 20 laser shots. The SNR improvement with the multipass cell is even higher for flame measurements at atmospheric pressure, because detector readout noise is more significant for single-pass measurements when the gas density is lower. Raman scattering is collected and dispersed in a spectrograph with a transmission grating and recorded with a fast gated CCD array detector to help eliminate flame interferences. The instrument is used to record spontaneous Raman spectra from N(2), CO(2), O(2), and CO in a methane-air flame. Curve fits of the recorded Raman spectra to detailed simulations of nitrogen spectra are used to determine the flame temperature from the shapes of the spectral signatures and from the ratio of the total intensities of the Stokes and anti-Stokes signals. The temperatures measured are in good agreement with radiation-corrected thermocouple measurements for a range of equivalence ratios. PMID:21857704

  15. Assessing clarity of message communication for mandated USEPA drinking water quality reports.

    PubMed

    Phetxumphou, Katherine; Roy, Siddhartha; Davy, Brenda M; Estabrooks, Paul A; You, Wen; Dietrich, Andrea M

    2016-04-01

    The United States Environmental Protection Agency mandates that community water systems (CWSs), or drinking water utilities, provide annual consumer confidence reports (CCRs) reporting on water quality, compliance with regulations, source water, and consumer education. While certain report formats are prescribed, there are no criteria ensuring that consumers understand messages in these reports. To assess clarity of message, trained raters evaluated a national sample of 30 CCRs using the Centers for Disease Control Clear Communication Index (Index) indices: (1) Main Message/Call to Action; (2) Language; (3) Information Design; (4) State of the Science; (5) Behavioral Recommendations; (6) Numbers; and (7) Risk. Communication materials are considered qualifying if they achieve a 90% Index score. Overall mean score across CCRs was 50 ± 14% and none scored 90% or higher. CCRs did not differ significantly by water system size. State of the Science (3 ± 15%) and Behavioral Recommendations (77 ± 36%) indices were the lowest and highest, respectively. Only 63% of CCRs explicitly stated if the water was safe to drink according to federal and state standards and regulations. None of the CCRs had passing Index scores, signaling that CWSs are not effectively communicating with their consumers; thus, the Index can serve as an evaluation tool for CCR effectiveness and a guide to improve water quality communications. PMID:27105408

  16. Tobacco industry manipulation messages in anti-smoking public service announcements: the effect of explicitly versus implicitly delivering messages.

    PubMed

    Shadel, William G; Fryer, Craig S; Tharp-Taylor, Shannah

    2010-05-01

    Message content in anti-smoking public service announcements (PSAs) can be delivered explicitly (directly with concrete statements) or implicitly (indirectly via metaphor), and the method of delivery may affect the efficacy of those PSAs. The purpose of this study was to conduct an initial test of this idea using tobacco industry manipulation PSAs in adolescents. A 2 (age: 11-14 years old; 15-17 years old)x2 (message delivery: implicit, explicit) mixed model design was used. There was a significant main effect of message delivery: Tobacco industry manipulation PSAs that delivered their messages explicitly were associated with stronger levels of smoking resistance self-efficacy compared to tobacco industry manipulation PSAs that delivered their messages implicitly. No significant main effects of age were found nor were any interactions between age and message delivery. These results suggest that message delivery factors should be taken into account when designing anti-smoking PSAs. PMID:20071100

  17. Short message service (SMS) text messaging as an intervention medium for weight loss: A literature review

    PubMed Central

    Shaw, Ryan; Bosworth, Hayden

    2013-01-01

    Nearly 68% of American adults are obese or overweight. Mobile devices such as mobile phones have emerged as a mode of intervention delivery to help people improve their health, particularly in relation to weight loss. This literature review examines the relationship between the use of short message service (SMS) text messaging as an intervention medium and weight loss. Results from this literature review (n = 14) suggest that SMS as an intervention tool for weight loss is still in its infancy. Initial results are promising but continued investigation is needed. We offer several recommendations for future research. PMID:23257055

  18. Genetic algorithms

    NASA Technical Reports Server (NTRS)

    Wang, Lui; Bayer, Steven E.

    1991-01-01

    Genetic algorithms are mathematical, highly parallel, adaptive search procedures (i.e., problem solving methods) based loosely on the processes of natural genetics and Darwinian survival of the fittest. Basic genetic algorithms concepts are introduced, genetic algorithm applications are introduced, and results are presented from a project to develop a software tool that will enable the widespread use of genetic algorithm technology.

  19. Generalized access control strategies for integrated services token passing systems

    NASA Astrophysics Data System (ADS)

    Pang, Joseph W. M.; Tobagi, Fouad A.; Boyd, Stephen

    1994-08-01

    The demand for integrated services local area networks is increasing at a rapid pace with the advent of many new and exciting applications: office and factory automation, distributed computing, and multimedia communications. To support these new applications, it is imperative to integrate traffic with diverse statistical characteristics and differing delay requirements on the same network. An attractive approach for integrating traffic has been adopted in two token passing local area network standards, the IEEE 802.4 token bus standard and FDDI. The idea is to control the transmissions of each station based on a distributed timing algorithm, so as to achieve the following goals: (1) to limit the token cycles so that time-critical traffic can be accommodated, and (2) to allocate pre-specified bandwidths to different stations when the network is overloaded. We have investigated the analysis and design of this protocol. In this paper, we generalize the transmission control algorithm used previously. The major advantages of the generalization over the original protocol are: (1) it provides a much expanded design space, (2) it guarantees convergent behavior, and (3) it gives meaningful insights into the dynamics of the basic control algorithm.

  20. Over-under double-pass interferometer

    NASA Technical Reports Server (NTRS)

    Schindler, R. A. (Inventor)

    1977-01-01

    An over-under double pass interferometer in which the beamsplitter area and thickness can be reduced to conform only with optical flatness considerations was achieved by offsetting the optical center line of one cat's-eye retroreflector relative to the optical center line of the other in order that one split beam be folded into a plane distinct from the other folded split beam. The beamsplitter is made transparent in one area for a first folded beam to be passed to a mirror for doubling back and is made totally reflective in another area for the second folded beam to be reflected to a mirror for doubling back. The two beams thus doubled back are combined in the central, beamsplitting area of the beamsplitting and passed to a detector. This makes the beamsplitter insensitive to minimum thickness requirements and selection of material.

  1. Getting your message out with social marketing.

    PubMed

    Manoff, R K

    1997-09-01

    This article was based on a speech presented at a Plenary Session of the 1996 Annual Meeting of the American Society of Tropical Medicine and Hygiene. The address describes the nature of social marketing with examples and some lessons learned in developing countries. The earliest social marketers were Moses with the Ten Commandments of God and Indian religious authorities with fertility motifs inscribed on temple walls. Modern marketers of beer and snack food preempted the ancients and made social marketing more ingenious. The strategy shifted to supplying a product to satisfy a consumer want. Messages became a two-way process that minimized feedback shock. Focus groups were used to probe consumers' thoughts. Research must probe the total environment of the "problem." In Brazil, breast feeding promotions revealed that the perceived problem may not be the real problem, and there was no single magic solution. Most tropical disease prevention approaches do not rely on multistage strategies. The oral rehydration therapy (ORT) strategy became a world-wide model when strategists realized that the formula had to be easy to remember, diarrhea had to be recognized as a disease, and the function of ORT had to be clearly defined. The Bangladesh Social Marketing Campaign was successful in getting men to discuss family planning with their wives and establishing the family planning worker as a heroine. Effective messages must uncover points of resistance to the message. Public health advances in the 19th century were due to social policy to improve water supply, sanitation, and nutrition. The iodization of salt in Ecuador was possible with political will, public awareness, redirection of perception, and motivation of demand. Social marketing resources exist in all countries nowadays. Only medical and scientific professionals can promote concern about tropical diseases and raise the prevention priority on the public agenda. PMID:9311633

  2. 78 FR 62344 - Sabine Pass Liquefaction Expansion, LLC, Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-18

    ... Sabine Pass LNG, L.P., Cheniere Creole Trail Pipeline, L.P.; Notice of Application Take notice that on... Commission an application under section 3(a) of the Natural Gas Act (NGA) for authorization to site...) filed, in the same application, a request under section 7(c) of the NGA, for authorization to...

  3. Continuity of the San Andreas Fault at San Gorgonio Pass

    NASA Astrophysics Data System (ADS)

    Carena, S.; Suppe, J.

    2002-12-01

    The San Andreas fault at San Gorgonio Pass does not have a clear surface trace and is considered aseismic. Our findings suggest in fact that the existence of a through-going vertical or near-vertical San Andreas fault between Yucaipa and North Palm Springs is highly unlikely. We mapped over 70 faults in the San Gorgonio Pass-San Bernardino Mountains region using the catalog of 43,500 relocated 1975-1998 earthquakes of Richards-Dinger and Shearer (2000). A clustering algorithm was applied to the relocated earthquakes in order to obtain tighter earthquake clouds and thus better-defined fault surfaces. The earthquakes were then imported into Gocad, a 3D modeling software that allowed us to separate earthquakes into coplanar clusters associated with different faults and fault strands and to fit optimized surfaces to them. We also used the catalog of 13,000 focal mechanisms of Hauksson (2000) to confirm the nature of the mapped faults. We were able to constrain the 3D geometry of the San Andreas fault near San Gorgonio Pass from the 3D geometry of the fault network surrounding it. None of these faults show any displacement due to an hypothetical sub-vertical San Andreas. The San Andreas fault must therefore rotate to much shallower dips, or lose its continuity at depths between 3 and 15 km The most likely configuration is the one where the San Andreas fault merges into the shallow-dipping San Gorgonio Pass thrust W of North Palm Springs. Strike-slip motion is taken up by both the thrust (the slip vector on the N. Palm Springs segment is reverse/right-lateral strike-slip) and by a series of NW striking faults in the footwall of the thrust. The W termination of the most active part of the San Gorgonio Pass thrust coincides with one of these footwall faults at depth, and with the south bend in the San Andreas fault strand N of Banning. This boundary also marks a change in the stress field, with a dominant strike-slip regime to the E (and localized thrusting between San

  4. The message processing and distribution system development

    NASA Astrophysics Data System (ADS)

    Whitten, K. L.

    1981-06-01

    A historical approach is used in presenting the life cycle development of the Navy's message processing and distribution system beginning with the planning phase and ending with the integrated logistic support phase. Several maintenance problems which occurred after the system was accepted for fleet use were examined to determine if they resulted from errors in the acquisition process. The critical decision points of the acquisition process are examined and constructive recommendations are made for avoiding the problems which hindered the successful development of this system.

  5. Research in Parallel Algorithms and Software for Computational Aerosciences

    NASA Technical Reports Server (NTRS)

    Domel, Neal D.

    1996-01-01

    Phase 1 is complete for the development of a computational fluid dynamics CFD) parallel code with automatic grid generation and adaptation for the Euler analysis of flow over complex geometries. SPLITFLOW, an unstructured Cartesian grid code developed at Lockheed Martin Tactical Aircraft Systems, has been modified for a distributed memory/massively parallel computing environment. The parallel code is operational on an SGI network, Cray J90 and C90 vector machines, SGI Power Challenge, and Cray T3D and IBM SP2 massively parallel machines. Parallel Virtual Machine (PVM) is the message passing protocol for portability to various architectures. A domain decomposition technique was developed which enforces dynamic load balancing to improve solution speed and memory requirements. A host/node algorithm distributes the tasks. The solver parallelizes very well, and scales with the number of processors. Partially parallelized and non-parallelized tasks consume most of the wall clock time in a very fine grain environment. Timing comparisons on a Cray C90 demonstrate that Parallel SPLITFLOW runs 2.4 times faster on 8 processors than its non-parallel counterpart autotasked over 8 processors.

  6. Research in Parallel Algorithms and Software for Computational Aerosciences

    NASA Technical Reports Server (NTRS)

    Domel, Neal D.

    1996-01-01

    Phase I is complete for the development of a Computational Fluid Dynamics parallel code with automatic grid generation and adaptation for the Euler analysis of flow over complex geometries. SPLITFLOW, an unstructured Cartesian grid code developed at Lockheed Martin Tactical Aircraft Systems, has been modified for a distributed memory/massively parallel computing environment. The parallel code is operational on an SGI network, Cray J90 and C90 vector machines, SGI Power Challenge, and Cray T3D and IBM SP2 massively parallel machines. Parallel Virtual Machine (PVM) is the message passing protocol for portability to various architectures. A domain decomposition technique was developed which enforces dynamic load balancing to improve solution speed and memory requirements. A host/node algorithm distributes the tasks. The solver parallelizes very well, and scales with the number of processors. Partially parallelized and non-parallelized tasks consume most of the wall clock time in a very fine grain environment. Timing comparisons on a Cray C90 demonstrate that Parallel SPLITFLOW runs 2.4 times faster on 8 processors than its non-parallel counterpart autotasked over 8 processors.

  7. 77 FR 65546 - Sabine Pass Liquefaction, LLC; Sabine Pass LNG, L.P.; Notice of Petition To Amend Authorizations...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ... Energy Regulatory Commission Sabine Pass Liquefaction, LLC; Sabine Pass LNG, L.P.; Notice of Petition To... Pass Liquefaction, LLC and Sabine Pass LNG, L.P. (collectively, Sabine Pass), 700 Milam Street, Suite... authorizations granted on April 16, 2012 in Docket No. CP11-72-000 (Liquefaction Project) in order to...

  8. 78 FR 66909 - Sabine Pass Liquefaction, LLC; Sabine Pass LNG, L.P.; Notice of Application to Amend...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... Energy Regulatory Commission Sabine Pass Liquefaction, LLC; Sabine Pass LNG, L.P.; Notice of Application... Sabine Pass Liquefaction, LLC and Sabine Pass LNG, L.P. (collectively, Sabine Pass), 700 Milam Street... authorizations granted on April 16, 2012 in Docket No. CP11-72-000 (Liquefaction Project), as amended in...

  9. Language Implications for Advertising in International Markets: A Model for Message Content and Message Execution.

    ERIC Educational Resources Information Center

    Beard, John; Yaprak, Attila

    A content analysis model for assessing advertising themes and messages generated primarily for United States markets to overcome barriers in the cultural environment of international markets was developed and tested. The model is based on three primary categories for generating, evaluating, and executing advertisements: rational, emotional, and…

  10. Source Credibility in Tobacco Control Messaging

    PubMed Central

    Schmidt, Allison M.; Ranney, Leah M.; Pepper, Jessica K.; Goldstein, Adam O.

    2016-01-01

    Objectives Perceived credibility of a message’s source can affect persuasion. This paper reviews how beliefs about the source of tobacco control messages may encourage attitude and behavior change. Methods We conducted a series of searches of the peer-reviewed literature using terms from communication and public health fields. We reviewed research on source credibility, its underlying concepts, and its relation to the persuasiveness of tobacco control messages. Results We recommend an agenda for future research to bridge the gaps between communication literature on source credibility and tobacco control research. Our recommendations are to study the impact of source credibility on persuasion with long-term behavior change outcomes, in different populations and demographic groups, by developing new credibility measures that are topic- and organization-specific, by measuring how credibility operates across media platforms, and by identifying factors that enhance credibility and persuasion. Conclusions This manuscript reviews the state of research on source credibility and identifies gaps that are maximally relevant to tobacco control communication. Knowing first whether a source is perceived as credible, and second, how to enhance perceived credibility, can inform the development of future tobacco control campaigns and regulatory communications. PMID:27525298

  11. Independent communication messages: methodology and applications

    SciTech Connect

    Cooper, J.A.

    1997-09-01

    Information flowing on communication buses is ordinarily ``non-random`` in the sense that data entities are not equally likely and independent. This is because they have relationships to each other and to physical occurrences to which they may be responding. Random data would convey no information or meaning. From a different viewpoint, there can be applications for creating randomness characteristics, and four of these are described in this paper. Two examples derive from cryptology and the other two from safety. One cryptology application described is the generation of random numbers for use as, for example, keys, hash functions, nonces, and seeds. The other is for inter-message ``padding`` to resist traffic analysis by masking when data are being transmitted and when the channel is conveying no information. One of the safety applications described is the ``unique signal`` approach used in modern nuclear weapon electrical safety. The other is the use of unique signals as non-weapon critical-operation control functions. Both of these safety applications require provisions to help assure randomness characteristics in any inadvertently occurring inputs. In order to satisfy these cryptology and safety needs, communication strategies are described that generate or selectively encourage independent (unrelated) symbols or messages.

  12. Passing the Bond Issue (with Related Video)

    ERIC Educational Resources Information Center

    Erickson, Paul W.

    2011-01-01

    When a bond referendum comes around for a school district, it often is the culmination of years of planning, strategizing and communicating to the public. Especially in these economic times, passing a building referendum is challenging. Complete transparency among the superintendent, school board and community is essential to communicate the…

  13. PASS: Creating Physically Active School Systems

    ERIC Educational Resources Information Center

    Ciotto, Carol M.; Fede, Marybeth H.

    2014-01-01

    PASS, a Physically Active School System, is a program by which school districts and schools utilize opportunities for school-based physical activity that enhance overall fitness and cognition, which can be broken down into four integral parts consisting of connecting, communicating, collaborating, and cooperating. There needs to be an…

  14. The Physics of "String Passing through Ice"

    ERIC Educational Resources Information Center

    Mohazzabi, Pirooz

    2011-01-01

    One of the oldest yet interesting experiments related to heat and thermodynamics is placing a string on a block of ice and hanging two masses from the ends of the string. Sometime later, it is discovered that the string has passed through the ice without cutting it in half. A simple explanation of this effect is that the pressure caused by the…

  15. Program for Access to Science Study (PASS).

    ERIC Educational Resources Information Center

    Roth, Millicent; Weiner, Michael

    The Program for Access to Science Study (PASS) consists of a preparatory science course which is taught in tandem with a special counseling seminar. Problem solving is taught using content in chemistry and physics. The curriculum is divided into cycles, each built around a single topic. A problem set related to the topic and an illustrative lab…

  16. Generalizing Galileo's Passe-Dix Game

    ERIC Educational Resources Information Center

    Hombas, Vassilios

    2012-01-01

    This article shows a generalization of Galileo's "passe-dix" game. The game was born following one of Galileo's [G. Galileo, "Sopra le Scoperte dei Dadi" (Galileo, Opere, Firenze, Barbera, Vol. 8). Translated by E.H. Thorne, 1898, pp. 591-594] explanations on a paradox that occurred in the experiment of tossing three fair "six-sided" dice.…

  17. PASS: Promoting Academic Student Success. Final Report.

    ERIC Educational Resources Information Center

    Miller, Kenneth; Sonner, Bruce

    Active between 1993 and 1996, the Promoting Academic Student Success (PASS) Program was aimed at reducing the high percentage of failure experienced by academic probation students at Corning Community College (New York). These students typically came from non supportive environments, possessed academic deficiencies, and suffered from feelings of…

  18. 34 CFR 668.147 - Passing scores.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be representative of the population of high school graduates in the United States. (Authority: 20 U.S... 34 Education 3 2011-07-01 2011-07-01 false Passing scores. 668.147 Section 668.147 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY...

  19. 34 CFR 668.147 - Passing scores.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... be representative of the population of high school graduates in the United States. (Authority: 20 U.S... 34 Education 3 2014-07-01 2014-07-01 false Passing scores. 668.147 Section 668.147 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY...

  20. 34 CFR 668.147 - Passing scores.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... be representative of the population of high school graduates in the United States. (Authority: 20 U.S... 34 Education 3 2012-07-01 2012-07-01 false Passing scores. 668.147 Section 668.147 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY...

  1. 34 CFR 668.147 - Passing scores.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be representative of the population of high school graduates in the United States. (Authority: 20 U.S... 34 Education 3 2013-07-01 2013-07-01 false Passing scores. 668.147 Section 668.147 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY...

  2. 34 CFR 668.147 - Passing scores.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standard deviation below the mean for students with high school diplomas who have taken the test within... 34 Education 3 2010-07-01 2010-07-01 false Passing scores. 668.147 Section 668.147 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY...

  3. On the Conceptual Ambiguity Surrounding Perceived Message Effectiveness

    PubMed Central

    Yzer, Marco; LoRusso, Susan; Nagler, Rebekah H.

    2015-01-01

    Health message quality is best understood in terms of a message’s ability to effectively produce change in the variables that it was designed to change. The importance of determining a message’s effectiveness in producing change prior to implementation is clear: The better a message’s potential effectiveness is understood, the better able interventionists are to distinguish effective from ineffective messages before allocating scarce resources to message implementation. For this purpose, research has relied on perceived message effectiveness measures as a proxy of a message’s potential effectiveness. Remarkably, however, very little conceptual work has been done on perceived message effectiveness, which renders its measures under-informed and inconsistent across studies. To encourage greater conceptual work on this important construct, we review several threats to the validity of existing measures and consider strategies for improving our understanding of perceived message effectiveness. PMID:25470437

  4. Breast cancer messaging for younger women: gender, femininity, and risk.

    PubMed

    Haines, Rebecca J; Bottorff, Joan L; Barclay McKeown, Stephanie; Ptolemy, Erin; Carey, Joanne; Sullivan, Kelli

    2010-06-01

    Evidence linking both active smoking and secondhand smoke exposure to premenopausal breast cancer makes the development of health messages specific to younger women a pressing priority. To determine how to communicate information about this modifiable breast cancer risk to young women, we analyzed a selection of 32 recent English-language breast cancer messages and campaigns that targeted young women. In addition, we obtained young women's responses to three breast cancer campaign images during focus group discussions. A visual analysis of messages points to an explicitly gendered discourse within contemporary campaigns, one that entails conflicting messages regarding breast cancer, health, feminine beauty, and risk. Although the intent might be to educate and empower young women to "fight" against breast cancer, paradoxically, the messages employ imagery that sexually objectifies young women's breasts and bodies. Recommendations are made for messaging about tobacco and breast cancer risk to avoid reproducing one-dimensional or stereotypical presentations of gender and femininity. PMID:20354237

  5. Music carries a message to youths.

    PubMed

    Coleman, P L

    1986-01-01

    The most widely played song in Mexico in March 1986 is a special record designed to encourage young people to be sexually responsible and not to bring into the world children they cannot care for. "It's OK to say 'no,'" is the message of a unique new family planning and health communication project designed to reach young people in 11 Spanish speaking countries of Latin America and the Caribbean. What makes this ambitious regional project so unique is not just the message or the remarkable success of the 1st song but the combination of materials that were produced, the way they were produced, and how they are now being used throughout the region. The Population Communication Services project in the Johns Hopkins School of Hygiene and Public Health (JHU/PCS) has been working in Latin America and elsewhere for 4 years to support innovative family planning communication projects. It became evident that 1 key group was not being reached, i.e., young people aged 13-18 who comprise approximately 30% of the total population in Latin America. The fertility and sexual behavior of young people have a significant impact on their own lives, their community, their country, and the region. Early pregnancy is a major health and social problem throughout the region and the world. To address this problem, the JHU/PCS decided to develop a regional Latin American project to make young people more sharply aware of the personal advantages to them of responsible parenthood. JHU/PCS put together a financial, marketing, and institutional package. The US Agency for International Development (USAID) provided the finances. Analysis showed that the common denominator for young people throughout the region is music. The decision was made to produce 2 songs, each with a music video, pressed on each side of 45 rpm single records and enclosed in a full-size, full-color, 2-sided record jacket which folds out into a poster. The next step was to refine the general message of sexual responsibility to

  6. Tabletop Molecular Communication: Text Messages through Chemical Signals

    PubMed Central

    Farsad, Nariman; Guo, Weisi; Eckford, Andrew W.

    2013-01-01

    In this work, we describe the first modular, and programmable platform capable of transmitting a text message using chemical signalling – a method also known as molecular communication. This form of communication is attractive for applications where conventional wireless systems perform poorly, from nanotechnology to urban health monitoring. Using examples, we demonstrate the use of our platform as a testbed for molecular communication, and illustrate the features of these communication systems using experiments. By providing a simple and inexpensive means of performing experiments, our system fills an important gap in the molecular communication literature, where much current work is done in simulation with simplified system models. A key finding in this paper is that these systems are often nonlinear in practice, whereas current simulations and analysis often assume that the system is linear. However, as we show in this work, despite the nonlinearity, reliable communication is still possible. Furthermore, this work motivates future studies on more realistic modelling, analysis, and design of theoretical models and algorithms for these systems. PMID:24367571

  7. Tabletop molecular communication: text messages through chemical signals.

    PubMed

    Farsad, Nariman; Guo, Weisi; Eckford, Andrew W

    2013-01-01

    In this work, we describe the first modular, and programmable platform capable of transmitting a text message using chemical signalling - a method also known as molecular communication. This form of communication is attractive for applications where conventional wireless systems perform poorly, from nanotechnology to urban health monitoring. Using examples, we demonstrate the use of our platform as a testbed for molecular communication, and illustrate the features of these communication systems using experiments. By providing a simple and inexpensive means of performing experiments, our system fills an important gap in the molecular communication literature, where much current work is done in simulation with simplified system models. A key finding in this paper is that these systems are often nonlinear in practice, whereas current simulations and analysis often assume that the system is linear. However, as we show in this work, despite the nonlinearity, reliable communication is still possible. Furthermore, this work motivates future studies on more realistic modelling, analysis, and design of theoretical models and algorithms for these systems. PMID:24367571

  8. Event Driven Messaging with Role-Based Subscriptions

    NASA Technical Reports Server (NTRS)

    Bui, Tung; Bui, Bach; Malhotra, Shantanu; Chen, Fannie; Kim, rachel; Allen, Christopher; Luong, Ivy; Chang, George; Zendejas, Silvino; Sadaqathulla, Syed

    2009-01-01

    Event Driven Messaging with Role-Based Subscriptions (EDM-RBS) is a framework integrated into the Service Management Database (SMDB) to allow for role-based and subscription-based delivery of synchronous and asynchronous messages over JMS (Java Messaging Service), SMTP (Simple Mail Transfer Protocol), or SMS (Short Messaging Service). This allows for 24/7 operation with users in all parts of the world. The software classifies messages by triggering data type, application source, owner of data triggering event (mission), classification, sub-classification and various other secondary classifying tags. Messages are routed to applications or users based on subscription rules using a combination of the above message attributes. This program provides a framework for identifying connected users and their applications for targeted delivery of messages over JMS to the client applications the user is logged into. EDMRBS provides the ability to send notifications over e-mail or pager rather than having to rely on a live human to do it. It is implemented as an Oracle application that uses Oracle relational database management system intrinsic functions. It is configurable to use Oracle AQ JMS API or an external JMS provider for messaging. It fully integrates into the event-logging framework of SMDB (Subnet Management Database).

  9. Belief propagation vs. TAP for decoding corrupted messages

    NASA Astrophysics Data System (ADS)

    Kabashima, Y.; Saad, D.

    1998-12-01

    We employ two different methods, based on belief propagation and TAP, for decoding corrupted messages encoded by employing Sourlas's method, where the code word comprises products of K bits selected randomly from the original message. We show that the equations obtained by the two approaches are similar and provide the same solution as the one obtained by the replica approach in some cases (K = 2). However, we also show that for K >= 3 and unbiased messages the iterative solution is sensitive to the initial conditions and is likely to provide erroneous solutions; and that it is generally beneficial to use Nishimori's temperature, especially in the case of biased messages.

  10. A uGNI-Based Asynchronous Message-driven Runtime System for Cray Supercomputers with Gemini Interconnect

    SciTech Connect

    Sun, Yanhua; Zheng, Gengbin; Olson, Ryan M; Jones, Terry R; Kale, Laxmikant V

    2012-01-01

    Gemini as the network for new Cray XE/XT systems features low latency, high bandwidth and strong scalability. Its hardware support for remote direct memory access enables efficient implementation of the global address space programming languages. Although the Generic Network Interface (GNI) is designed to support message-passing applications, it is still challenging to attain good performance for applications written in alternative programming models, such as the message-driven programming model. In our earlier work we showed that CHARM++, an object-oriented message-driven programming model, scales up to the full Jaguar Cray machine. In this paper, we describe a general and light-weight asynchronous Low-level RunTime System (LRTS) for CHARM+, and its implementation on the uGNI software stack for Cray XE systems. Several techniques are presented to exploit the uGNI capability by reducing memory copy and registration overhead, taking advantage of persistent communication, and improving intra-node communication. Our micro-benchmark results demonstrate that the uGNI-based runtime system outperforms the MPI-based implementation by up to 50% in terms of message latency. For communication intensive applications such as N-Queens, this implementation scales up to 15,360 cores of a Cray XE6 machine and is 70% faster than an MPI-based implementation. In molecular dynamics application NAMD, the performance is also considerably improved by as high as 18%.

  11. Bilingual Text Messaging Translation: Translating Text Messages From English Into Spanish for the Text4Walking Program

    PubMed Central

    Sandi, Giselle; Ingram, Diana; Welch, Mary Jane; Ocampo, Edith V

    2015-01-01

    Background Hispanic adults in the United States are at particular risk for diabetes and inadequate blood pressure control. Physical activity improves these health problems; however Hispanic adults also have a low rate of recommended aerobic physical activity. To address improving physical inactivity, one area of rapidly growing technology that can be utilized is text messaging (short message service, SMS). A physical activity research team, Text4Walking, had previously developed an initial database of motivational physical activity text messages in English that could be used for physical activity text messaging interventions. However, the team needed to translate these existing English physical activity text messages into Spanish in order to have culturally meaningful and useful text messages for those adults within the Hispanic population who would prefer to receive text messages in Spanish. Objective The aim of this study was to translate a database of English motivational physical activity messages into Spanish and review these text messages with a group of Spanish speaking adults to inform the use of these text messages in an intervention study. Methods The consent form and study documents, including the existing English physical activity text messages, were translated from English into Spanish, and received translation certification as well as Institutional Review Board approval. The translated text messages were placed into PowerPoint, accompanied by a set of culturally appropriate photos depicting barriers to walking, as well as walking scenarios. At the focus group, eligibility criteria for this study included being an adult between 30 to 65 years old who spoke Spanish as their primary language. After a general group introduction, participants were placed into smaller groups of two or three. Each small group was asked to review a segment of the translated text messages for accuracy and meaningfulness. After the break out, the group was brought back together

  12. Message transfer service for space applications

    NASA Technical Reports Server (NTRS)

    Shames, P.

    2002-01-01

    Spacecraft applications that interact with on-board sensors, effectors, and major components have traditionally used private interfaces which are tightly bound to the interface details of the data links connecting these sub-systems. The latest spacecraft, which often include several powerful processors running real time operating systems, high-speed on-board networks, and intelligent peripherals, can support a more layered networked environment. Use of standard interfaces and networked elements is expected to yield reusable software and hardware components. Within CCSDS Panel 1K we have been developing such on-board interface standards. This paper will present a Message Transfer Service that defines a common API for use within a single spacecraft or among spacecraft flying in a constellation.

  13. Protocols for Handling Messages Between Simulation Computers

    NASA Technical Reports Server (NTRS)

    Balcerowski, John P.; Dunnam, Milton

    2006-01-01

    Practical Simulator Network (PSimNet) is a set of data-communication protocols designed especially for use in handling messages between computers that are engaging cooperatively in real-time or nearly-real-time training simulations. In a typical application, computers that provide individualized training at widely dispersed locations would communicate, by use of PSimNet, with a central host computer that would provide a common computational- simulation environment and common data. Originally intended for use in supporting interfaces between training computers and computers that simulate the responses of spacecraft scientific payloads, PSimNet could be especially well suited for a variety of other applications -- for example, group automobile-driver training in a classroom. Another potential application might lie in networking of automobile-diagnostic computers at repair facilities to a central computer that would compile the expertise of numerous technicians and engineers and act as an expert consulting technician.

  14. Pass-Fail: How Is It Working?

    ERIC Educational Resources Information Center

    Chase, Clinton I.; And Others

    This study investigates the pass/fail (P/F) grading system. A sample of 154 Indiana University students was interviewed. Half of the group, 77 students, had not taken any P/F courses. Of the remaining 77 students, 42% had taken only one P/F course and most of the rest from two to five courses. Results of the student interview questionnaire…

  15. Battery Cell By-Pass Circuit

    NASA Technical Reports Server (NTRS)

    Mumaw, Susan J. (Inventor); Evers, Jeffrey (Inventor); Craig, Calvin L., Jr. (Inventor); Walker, Stuart D. (Inventor)

    2001-01-01

    The invention is a circuit and method of limiting the charging current voltage from a power supply net work applied to an individual cell of a plurality of cells making up a battery being charged in series. It is particularly designed for use with batteries that can be damaged by overcharging, such as Lithium-ion type batteries. In detail. the method includes the following steps: 1) sensing the actual voltage level of the individual cell; 2) comparing the actual voltage level of the individual cell with a reference value and providing an error signal representative thereof; and 3) by-passing the charging current around individual cell necessary to keep the individual cell voltage level generally equal a specific voltage level while continuing to charge the remaining cells. Preferably this is accomplished by by-passing the charging current around the individual cell if said actual voltage level is above the specific voltage level and allowing the charging current to the individual cell if the actual voltage level is equal or less than the specific voltage level. In the step of bypassing the charging current, the by-passed current is transferred at a proper voltage level to the power supply. The by-pass circuit a voltage comparison circuit is used to compare the actual voltage level of the individual cell with a reference value and to provide an error signal representative thereof. A third circuit, designed to be responsive to the error signal, is provided for maintaining the individual cell voltage level generally equal to the specific voltage level. Circuitry is provided in the third circuit for bypassing charging current around the individual cell if the actual voltage level is above the specific voltage level and transfers the excess charging current to the power supply net work. The circuitry also allows charging of the individual cell if the actual voltage level is equal or less than the specific voltage level.

  16. TE and TM pass integrated optic polarizers

    NASA Astrophysics Data System (ADS)

    Madaan, Divya; Kaur, Davinder; Sharma, V. K.; Kapoor, A.

    2016-05-01

    A four layer integrated optical waveguide is studied, in which a high index buffer is used along with the metal cladding. The structure can act both as TE and TM pass polarizer. We have designed it for λ=1.55 µm which corresponds to telecommunication wavelength. TiO2 is used as a buffer layer with Au as metal cladding. When metal clad optical waveguides with a high index buffer layer are used there is periodic coupling between lossless modes of waveguide and the lossy modes supported by high index buffer layer with metal clad. We present theoretical results of the effect of buffer thickness on the mode index and the losses. The TM Pass polarizer with TE and TM losses, 1029.19dB/cm and 59.67dB/cm respectively are obtained. Also, TE Pass polarizer with TM and TE losses 1444.74dB/cm and 238.51dB/cm respectively are obtained.

  17. Adaptive Numerical Algorithms in Space Weather Modeling

    NASA Technical Reports Server (NTRS)

    Toth, Gabor; vanderHolst, Bart; Sokolov, Igor V.; DeZeeuw, Darren; Gombosi, Tamas I.; Fang, Fang; Manchester, Ward B.; Meng, Xing; Nakib, Dalal; Powell, Kenneth G.; Stout, Quentin F.; Glocer, Alex; Ma, Ying-Juan; Opher, Merav

    2010-01-01

    Space weather describes the various processes in the Sun-Earth system that present danger to human health and technology. The goal of space weather forecasting is to provide an opportunity to mitigate these negative effects. Physics-based space weather modeling is characterized by disparate temporal and spatial scales as well as by different physics in different domains. A multi-physics system can be modeled by a software framework comprising of several components. Each component corresponds to a physics domain, and each component is represented by one or more numerical models. The publicly available Space Weather Modeling Framework (SWMF) can execute and couple together several components distributed over a parallel machine in a flexible and efficient manner. The framework also allows resolving disparate spatial and temporal scales with independent spatial and temporal discretizations in the various models. Several of the computationally most expensive domains of the framework are modeled by the Block-Adaptive Tree Solar wind Roe Upwind Scheme (BATS-R-US) code that can solve various forms of the magnetohydrodynamics (MHD) equations, including Hall, semi-relativistic, multi-species and multi-fluid MHD, anisotropic pressure, radiative transport and heat conduction. Modeling disparate scales within BATS-R-US is achieved by a block-adaptive mesh both in Cartesian and generalized coordinates. Most recently we have created a new core for BATS-R-US: the Block-Adaptive Tree Library (BATL) that provides a general toolkit for creating, load balancing and message passing in a 1, 2 or 3 dimensional block-adaptive grid. We describe the algorithms of BATL and demonstrate its efficiency and scaling properties for various problems. BATS-R-US uses several time-integration schemes to address multiple time-scales: explicit time stepping with fixed or local time steps, partially steady-state evolution, point-implicit, semi-implicit, explicit/implicit, and fully implicit numerical

  18. Adaptive numerical algorithms in space weather modeling

    NASA Astrophysics Data System (ADS)

    Tóth, Gábor; van der Holst, Bart; Sokolov, Igor V.; De Zeeuw, Darren L.; Gombosi, Tamas I.; Fang, Fang; Manchester, Ward B.; Meng, Xing; Najib, Dalal; Powell, Kenneth G.; Stout, Quentin F.; Glocer, Alex; Ma, Ying-Juan; Opher, Merav

    2012-02-01

    Space weather describes the various processes in the Sun-Earth system that present danger to human health and technology. The goal of space weather forecasting is to provide an opportunity to mitigate these negative effects. Physics-based space weather modeling is characterized by disparate temporal and spatial scales as well as by different relevant physics in different domains. A multi-physics system can be modeled by a software framework comprising several components. Each component corresponds to a physics domain, and each component is represented by one or more numerical models. The publicly available Space Weather Modeling Framework (SWMF) can execute and couple together several components distributed over a parallel machine in a flexible and efficient manner. The framework also allows resolving disparate spatial and temporal scales with independent spatial and temporal discretizations in the various models. Several of the computationally most expensive domains of the framework are modeled by the Block-Adaptive Tree Solarwind Roe-type Upwind Scheme (BATS-R-US) code that can solve various forms of the magnetohydrodynamic (MHD) equations, including Hall, semi-relativistic, multi-species and multi-fluid MHD, anisotropic pressure, radiative transport and heat conduction. Modeling disparate scales within BATS-R-US is achieved by a block-adaptive mesh both in Cartesian and generalized coordinates. Most recently we have created a new core for BATS-R-US: the Block-Adaptive Tree Library (BATL) that provides a general toolkit for creating, load balancing and message passing in a 1, 2 or 3 dimensional block-adaptive grid. We describe the algorithms of BATL and demonstrate its efficiency and scaling properties for various problems. BATS-R-US uses several time-integration schemes to address multiple time-scales: explicit time stepping with fixed or local time steps, partially steady-state evolution, point-implicit, semi-implicit, explicit/implicit, and fully implicit

  19. Individual differences in drivers' cognitive processing of road safety messages.

    PubMed

    Kaye, Sherrie-Anne; White, Melanie J; Lewis, Ioni M

    2013-01-01

    Using Gray and McNaughton's (2000) revised reinforcement sensitivity theory (r-RST), we examined the influence of personality on processing of words presented in gain-framed and loss-framed anti-speeding messages and how the processing biases associated with personality influenced message acceptance. The r-RST predicts that the nervous system regulates personality and that behaviour is dependent upon the activation of the behavioural activation system (BAS), activated by reward cues and the fight-flight-freeze system (FFFS), activated by punishment cues. According to r-RST, individuals differ in the sensitivities of their BAS and FFFS (i.e., weak to strong), which in turn leads to stable patterns of behaviour in the presence of rewards and punishments, respectively. It was hypothesised that individual differences in personality (i.e., strength of the BAS and the FFFS) would influence the degree of both message processing (as measured by reaction time to previously viewed message words) and message acceptance (measured three ways by perceived message effectiveness, behavioural intentions, and attitudes). Specifically, it was anticipated that, individuals with a stronger BAS would process the words presented in the gain-frame messages faster than those with a weaker BAS and individuals with a stronger FFFS would process the words presented in the loss-frame messages faster than those with a weaker FFFS. Further, it was expected that greater processing (faster reaction times) would be associated with greater acceptance for that message. Driver licence holding students (N=108) were recruited to view one of four anti-speeding messages (i.e., social gain-frame, social loss-frame, physical gain-frame, and physical loss-frame). A computerised lexical decision task assessed participants' subsequent reaction times to message words, as an indicator of the extent of processing of the previously viewed message. Self-report measures assessed personality and the three message

  20. 7 CFR 29.97 - Who shall pass upon appeals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Who shall pass upon appeals. 29.97 Section 29.97... REGULATIONS TOBACCO INSPECTION Regulations Appeal § 29.97 Who shall pass upon appeals. Appeals shall be passed... shall pass upon an appeal involving the correctness of a certificate issued or sample prepared by him....

  1. A massively parallel algorithm for the collision probability calculations in the Apollo-II code using the PVM library

    SciTech Connect

    Stankovski, Z.

    1995-12-31

    The collision probability method in neutron transport, as applied to 2D geometries, consume a great amount of computer time, for a typical 2D assembly calculation about 90% of the computing time is consumed in the collision probability evaluations. Consequently RZ or 3D calculations became prohibitive. In this paper the author presents a simple but efficient parallel algorithm based on the message passing host/node programmation model. Parallelization was applied to the energy group treatment. Such approach permits parallelization of the existing code, requiring only limited modifications. Sequential/parallel computer portability is preserved, which is a necessary condition for a industrial code. Sequential performances are also preserved. The algorithm is implemented on a CRAY 90 coupled to a 128 processor T3D computer, a 16 processor IBM SPI and a network of workstations, using the Public Domain PVM library. The tests were executed for a 2D geometry with the standard 99-group library. All results were very satisfactory, the best ones with IBM SPI. Because of heterogeneity of the workstation network, the author did not ask high performances for this architecture. The same source code was used for all computers. A more impressive advantage of this algorithm will appear in the calculations of the SAPHYR project (with the future fine multigroup library of about 8000 groups) with a massively parallel computer, using several hundreds of processors.

  2. A master-slave parallel hybrid multi-objective evolutionary algorithm for groundwater remediation design under general hydrogeological conditions

    NASA Astrophysics Data System (ADS)

    Wu, J.; Yang, Y.; Luo, Q.; Wu, J.

    2012-12-01

    This study presents a new hybrid multi-objective evolutionary algorithm, the niched Pareto tabu search combined with a genetic algorithm (NPTSGA), whereby the global search ability of niched Pareto tabu search (NPTS) is improved by the diversification of candidate solutions arose from the evolving nondominated sorting genetic algorithm II (NSGA-II) population. Also, the NPTSGA coupled with the commonly used groundwater flow and transport codes, MODFLOW and MT3DMS, is developed for multi-objective optimal design of groundwater remediation systems. The proposed methodology is then applied to a large-scale field groundwater remediation system for cleanup of large trichloroethylene (TCE) plume at the Massachusetts Military Reservation (MMR) in Cape Cod, Massachusetts. Furthermore, a master-slave (MS) parallelization scheme based on the Message Passing Interface (MPI) is incorporated into the NPTSGA to implement objective function evaluations in distributed processor environment, which can greatly improve the efficiency of the NPTSGA in finding Pareto-optimal solutions to the real-world application. This study shows that the MS parallel NPTSGA in comparison with the original NPTS and NSGA-II can balance the tradeoff between diversity and optimality of solutions during the search process and is an efficient and effective tool for optimizing the multi-objective design of groundwater remediation systems under complicated hydrogeologic conditions.

  3. A Parallel Non-Overlapping Domain-Decomposition Algorithm for Compressible Fluid Flow Problems on Triangulated Domains

    NASA Technical Reports Server (NTRS)

    Barth, Timothy J.; Chan, Tony F.; Tang, Wei-Pai

    1998-01-01

    This paper considers an algebraic preconditioning algorithm for hyperbolic-elliptic fluid flow problems. The algorithm is based on a parallel non-overlapping Schur complement domain-decomposition technique for triangulated domains. In the Schur complement technique, the triangulation is first partitioned into a number of non-overlapping subdomains and interfaces. This suggests a reordering of triangulation vertices which separates subdomain and interface solution unknowns. The reordering induces a natural 2 x 2 block partitioning of the discretization matrix. Exact LU factorization of this block system yields a Schur complement matrix which couples subdomains and the interface together. The remaining sections of this paper present a family of approximate techniques for both constructing and applying the Schur complement as a domain-decomposition preconditioner. The approximate Schur complement serves as an algebraic coarse space operator, thus avoiding the known difficulties associated with the direct formation of a coarse space discretization. In developing Schur complement approximations, particular attention has been given to improving sequential and parallel efficiency of implementations without significantly degrading the quality of the preconditioner. A computer code based on these developments has been tested on the IBM SP2 using MPI message passing protocol. A number of 2-D calculations are presented for both scalar advection-diffusion equations as well as the Euler equations governing compressible fluid flow to demonstrate performance of the preconditioning algorithm.

  4. Effects of Targeted Sales Messages on Subscription Sales and Retention.

    ERIC Educational Resources Information Center

    Gamst, Glenn; And Others

    1987-01-01

    Investigates the effects of targeted sales messages on newspaper subscription sales and retention by combining two large research projects--a demographic market segmentation scheme, and a readership-lifestyle survey. Proposes that the content of sales messages influences new subscriptions but does not affect retention. (MM)

  5. Resonant Messages to Prevent Prescription Drug Misuse by Teens

    ERIC Educational Resources Information Center

    Twombly, Eric C.; Holtz, Kristen D.; Agnew, Christine B.

    2011-01-01

    Prescription drug misuse is a major health problem, particularly among teens. A key step in curbing misuse is the development of effective prescription drug prevention messages. This paper explores the elements of prescription drug misuse prevention messages that resonate with teens using data from focus groups with seventh and eighth grade…

  6. Persuasion with Unintelligible Messages: A Cognitive Response Analysis.

    ERIC Educational Resources Information Center

    Padgett, Vernon R.; Brock, Timothy C.

    Theories of persuasion have long assumed a process which includes comprehension of the message by the recipient. Several hundred undergraduates at Ohio State University and Marshall University (Ohio) participated in six experiments examining persuasion and the use of unintelligible messages. Subjects in individual cubicles of a university language…

  7. 47 CFR 36.379 - Message processing expense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Customer Operations Expenses § 36.379 Message processing expense. (a) This classification includes the salary and machine expense of data processing equipment, including supervision, general accounting... 47 Telecommunication 2 2011-10-01 2011-10-01 false Message processing expense. 36.379 Section...

  8. 47 CFR 36.379 - Message processing expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Customer Operations Expenses § 36.379 Message processing expense. (a) This classification includes the salary and machine expense of data processing equipment, including supervision, general accounting... 47 Telecommunication 2 2012-10-01 2012-10-01 false Message processing expense. 36.379 Section...

  9. 47 CFR 36.379 - Message processing expense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Customer Operations Expenses § 36.379 Message processing expense. (a) This classification includes the salary and machine expense of data processing equipment, including supervision, general accounting... 47 Telecommunication 2 2014-10-01 2014-10-01 false Message processing expense. 36.379 Section...

  10. 47 CFR 97.219 - Message forwarding system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Message forwarding system. 97.219 Section 97.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station...

  11. 47 CFR 97.219 - Message forwarding system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Message forwarding system. 97.219 Section 97.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station...

  12. 47 CFR 97.219 - Message forwarding system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Message forwarding system. 97.219 Section 97.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station...

  13. 47 CFR 97.219 - Message forwarding system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Message forwarding system. 97.219 Section 97.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station...

  14. 47 CFR 97.219 - Message forwarding system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Message forwarding system. 97.219 Section 97.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station...

  15. Emotional Responses to Environmental Messages and Future Behavioral Intentions

    ERIC Educational Resources Information Center

    Perrin, Jeffrey L.

    2011-01-01

    The present research investigated effects of message framing (losses-framed or gains-framed), message modality (video with text or text-only) and emotional arousal on environmentally responsible behavioral intentions. The sample consisted of 161 college students. The present research did not find a significant difference in behavioral intentions…

  16. Gender and Student Reception of a Seminary's Dominant Messages

    ERIC Educational Resources Information Center

    Lincoln, Timothy D.

    2012-01-01

    Theological schools seek to educate both women and men to serve the church and promote the study of religion. This education involves constant messaging through multiple channels. This article explores the central messages received by theological students at one free-standing Presbyterian seminary in the United States. Women commonly reported two…

  17. Using Text Messaging to Support Administrative Communication in Higher Education

    ERIC Educational Resources Information Center

    Naismith, Laura

    2007-01-01

    To be effective in higher education, text messaging must be effectively integrated into both the student and staff experience. These user groups provided input into the design of StudyLink, an email to text message service. A small-scale trial was conducted over a period of two academic terms to investigate the feasibility of using this system in…

  18. Getting Your Message out (And Why It's Not Enough)

    ERIC Educational Resources Information Center

    Johnson, Jean

    2015-01-01

    Sometimes, education leaders are so intent on getting their message out that they neglect the other side of the equation--listening. In this article, Jean Johnson of Public Agenda describes the conditions that make "messaging" a perilous undertaking today. "These are skeptical times," she explains, in which Americans are…

  19. International Students, University Health Centers, and Memorable Messages about Health

    ERIC Educational Resources Information Center

    Carmack, Heather J.; Bedi, Shireen; Heiss, Sarah N.

    2016-01-01

    International students entering US universities often experience a variety of important socialization messages. One important message is learning about and using the US health system. International students often first encounter the US health system through their experiences with university health centers. The authors explore the memorable…

  20. And Now, a Message for Today's Students from Ben Franklin.

    ERIC Educational Resources Information Center

    Levy, Tedd

    1991-01-01

    Suggests that Benjamin Franklin's autobiography contains many useful messages for today's students. Discusses Franklin's list of virtues that he followed in an attempt at attaining moral perfection. Includes temperance, industry, justice, tranquillity, and humility. Describes the message of Franklin's lesson as one of achieving through effort…

  1. Multiculturalism and AIDS: different communities mean different educational messages required

    PubMed Central

    Lechky, O

    1997-01-01

    Having a multitude of different ethnic communities forces Canada's AIDS educators to use many different methods to deliver their messages. These range from an AIDS bingo game that has been used to educate natives in northern Manitoba to attempts to take AIDS education to the streets of Toronto. With AIDS education, reports Olga Lechky, one message definitely does not fit all. PMID:9164407

  2. Text Messaging as a Tool for Engaging Chemical Engineering Students

    ERIC Educational Resources Information Center

    Walton, S. Patrick; Briedis, Daina; Lindeman, Stephen D.; Malefyt, Amanda P.; Sticklen, Jon

    2012-01-01

    Maximizing student learning is first about engaging students. We investigated whether allowing students to use text messaging for course communication would enhance student instructor communication and concomitantly student engagement. We found that students did not prefer using text messaging for communicating with their instructor but that the…

  3. College Students' Text Messaging, Use of Textese and Literacy Skills

    ERIC Educational Resources Information Center

    Drouin, M. A.

    2011-01-01

    In this study, I examined reported frequency of text messaging, use of textese and literacy skills (reading accuracy, spelling and reading fluency) in a sample of American college students. Participants reported using text messaging, social networking sites and textese more often than was reported in previous (2009) research, and their frequency…

  4. The Operation of Categorization and Consistency Rules in Message Interpretation.

    ERIC Educational Resources Information Center

    Street, Richard L., Jr.

    Sacks's description-by-categorization theory was tested in a study to determine how contextual information influences the interpretation of verbal messages. The technique of enjambed conversation (a transcription of a conversation void of punctuation and speaker designation) was used to produce two verbal messages, one "more related" the other…

  5. Toward a Hierarchical Processing Model of Audio Advertising Messages.

    ERIC Educational Resources Information Center

    Stacks, Don W.; Melson, William H.

    Research shows that information received by one brain hemisphere (e.g., auditory messages entering the right ear) is processed and transferred to the other, interpretation being a combination of right and left brain processing, with high intensity messages shifting control from the left to the right brain. If information is received by one…

  6. Message framing and credibility: application in dental services.

    PubMed

    Arora, R

    2000-01-01

    This study uses an experimental approach to test the influence of message framing and credibility on the attitude toward a dental exam and consumers' intention to use the dental office. The findings indicate a strong effect of credibility on attitude as well as intention. The influence of framing is also statistically significant. Implications for marketers in terms of message strategy are discussed. PMID:11184434

  7. A Study Comparing Electronic Mail and Voice Messaging Channels.

    ERIC Educational Resources Information Center

    Gluck, Myke; And Others

    1991-01-01

    Describes a study that explored differences in computer-mediated communication messaging by comparing electronic mail and voice messaging used for giving directions. Highlights include a computational linguistic framework that examines differences between written and oral English, models of direction provision, and hypotheses based on preliminary…

  8. Seventh Grade Students and the Visual Messages They Love

    ERIC Educational Resources Information Center

    De Abreu, Belinha

    2008-01-01

    Most seventh grade students partially define themselves through everyday media messages. As a part of understanding how these images and the media impacts their lives, the author collaborated with her colleagues to develop a unit to help teens learn how visual messages such as those in pictures, media icons, logos, slogans, clothing, toys, and…

  9. Children's Text Messaging: Abbreviations, Input Methods and Links with Literacy

    ERIC Educational Resources Information Center

    Kemp, N.; Bushnell, C.

    2011-01-01

    This study investigated the effects of mobile phone text-messaging method (predictive and multi-press) and experience (in texters and non-texters) on children's textism use and understanding. It also examined popular claims that the use of text-message abbreviations, or "textese" spelling, is associated with poor literacy skills. A sample of 86…

  10. Undergraduates' Text Messaging Language and Literacy Skills

    ERIC Educational Resources Information Center

    Grace, Abbie; Kemp, Nenagh; Martin, Frances Heritage; Parrila, Rauno

    2014-01-01

    Research investigating whether people's literacy skill is being affected by the use of text messaging language has produced largely positive results for children, but mixed results for adults. We asked 150 undergraduate university students in Western Canada and 86 in South Eastern Australia to supply naturalistic text messages and to complete…

  11. Message frames interact with motivational systems to determine depth of message processing.

    PubMed

    Shen, Lijiang; Dillard, James Price

    2009-09-01

    Although several theoretical perspectives predict that negatively framed messages will be processed more deeply than positively framed messages, a recent meta-analysis found no such difference. In this article, the authors explore 2 explanations for this inconsistency. One possibility is methodological: the statistics used in the primary studies underestimated framing effects on depth of message processing because the data were maldistributed. The other is theoretical: the absence of a main effect is veridical, but framing interacts with individual differences that predispose individuals to greater or lesser depth of processing. Data from 2 experiments (Ns = 286 and 252) were analyzed via tobit regression, a technique designed to overcome the limitations of maldistributed data. One study showed the predicted main effect for framing, but the other did not. Both studies showed the anticipated interaction: Depth of processing correlated positively with a measure of the behavioral activation system in the advantage framing condition, whereas depth of processing correlated positively with the behavioral inhibition system in the disadvantage framing condition. PMID:19735028

  12. Two-dimensional inversion of spectral induced polarization data using MPI parallel algorithm in data space

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi-Yong; Tan, Han-Dong; Wang, Kun-Peng; Lin, Chang-Hong; Zhang, Bin; Xie, Mao-Bi

    2016-03-01

    Traditional two-dimensional (2D) complex resistivity forward modeling is based on Poisson's equation but spectral induced polarization (SIP) data are the coproducts of the induced polarization (IP) and the electromagnetic induction (EMI) effects. This is especially true under high frequencies, where the EMI effect can exceed the IP effect. 2D inversion that only considers the IP effect reduces the reliability of the inversion data. In this paper, we derive differential equations using Maxwell's equations. With the introduction of the Cole-Cole model, we use the finite-element method to conduct 2D SIP forward modeling that considers the EMI and IP effects simultaneously. The data-space Occam method, in which different constraints to the model smoothness and parametric boundaries are introduced, is then used to simultaneously obtain the four parameters of the Cole—Cole model using multi-array electric field data. This approach not only improves the stability of the inversion but also significantly reduces the solution ambiguity. To improve the computational efficiency, message passing interface programming was used to accelerate the 2D SIP forward modeling and inversion. Synthetic datasets were tested using both serial and parallel algorithms, and the tests suggest that the proposed parallel algorithm is robust and efficient.

  13. Design and implementation of a hybrid MPI-CUDA model for the Smith-Waterman algorithm.

    PubMed

    Khaled, Heba; Faheem, Hossam El Deen Mostafa; El Gohary, Rania

    2015-01-01

    This paper provides a novel hybrid model for solving the multiple pair-wise sequence alignment problem combining message passing interface and CUDA, the parallel computing platform and programming model invented by NVIDIA. The proposed model targets homogeneous cluster nodes equipped with similar Graphical Processing Unit (GPU) cards. The model consists of the Master Node Dispatcher (MND) and the Worker GPU Nodes (WGN). The MND distributes the workload among the cluster working nodes and then aggregates the results. The WGN performs the multiple pair-wise sequence alignments using the Smith-Waterman algorithm. We also propose a modified implementation to the Smith-Waterman algorithm based on computing the alignment matrices row-wise. The experimental results demonstrate a considerable reduction in the running time by increasing the number of the working GPU nodes. The proposed model achieved a performance of about 12 Giga cell updates per second when we tested against the SWISS-PROT protein knowledge base running on four nodes. PMID:26510289

  14. Enhancing the effectiveness of media messages promoting regular breast self-examination: messages based on innovation adoption principles.

    PubMed

    Howe, H L

    1981-01-01

    As public health departments have come to rely more and more on the mass media for the promotion of healthful behavior, it has become increasingly desirable to determine the motivating capability of the messages used in this promotion. A fact that is well understood is that many times any message at all is better than none. However, the effectiveness of various media health messages has not been well researched.A study was therefore undertaken of the comparative effectiveness of two different messages describing how to do a breast self-examination. An "experimental message" for the study was designed by applying the principles that facilitate innovation adoption to the message's format and presentation. This message's impact was then compared with that of the American Cancer Society's pamphlet "How To Examine Your Breasts." This pamphlet had been mailed to a sample of women similar to those receiving the experimental message, but who lived in a different geographic area. The use in each area of control groups who had received no messages afforded an opportunity to study maturation effects (other factors than the mailings that might have influenced study results).The experimental message proved more successful in persuading women to adopt breast self-examination than the comparison message. The women who reported a change in breast self-examination practice following the mailing could be characterized as having a more extensive social support system to promote breast examinations and as having a pre-experiment perception that breast self-examination was a complex practice to perform repeatedly at regular intervals. PMID:7208797

  15. Feelings about Verbal Aggression: Justifications for Sending and Hurt from Receiving Verbally Aggressive Messages.

    ERIC Educational Resources Information Center

    Martin, Matthew M.; And Others

    1996-01-01

    Investigates whether receiving verbally aggressive messages was more hurtful depending on the source of the message; whether trait verbal aggression is justified; and whether the perceived hurt of verbally aggressive messages is related to a tendency to be verbally aggressive. Finds that messages from friends caused more hurt than messages from…

  16. Efficient algorithms for distributed simulation and related problems

    SciTech Connect

    Kumar, D.

    1987-01-01

    This thesis presents efficient algorithms for distributed simulation, and for the related problems of termination detection and sequential simulation. Distributed simulation algorithms applicable to the simulation of special classes of systems, such that almost no overhead messages are required are presented. By contrast, previous distributed simulation algorithms, although applicable to the general class of any discrete-event system, usually require too many overhead messages. First, a simple distributed simulation algorithm is defined with nearly zero overhead messages for simulating feedforward systems. An approximate method is developed to predict its performance in simulating a class of feedforward-queuing networks. Performance of the scheme is evaluated in simulating specific subclasses of these queuing networks. It is shown that the scheme offers a high performance for serial-parallel networks. Next, another distributed simulation scheme is defined for a class of distributed systems whose topologies may have cycles. One important problem in devising distributed simulation algorithms is that of efficient detection of termination. With this in mind, a class of termination-detection algorithms using markers is devised. Finally, a new sequential simulation algorithm is developed, based on a distributed one. This algorithm often reduces the event-list manipulations of traditional-event list-driven simulation.

  17. Developing Concurrency Messages for the Black Community in Seattle, Washington

    PubMed Central

    Chapman, Caitlin Hughes; Clad, Rachel; Murray, Kate; Foster, Jennifer; Morris, Martina; Parks, Malcolm R.; Kurth, Ann Elizabeth

    2013-01-01

    In the United States, Blacks are disproportionately impacted by HIV/AIDS. Sexual networks and concurrent relationships have emerged as important contributors to the heterosexual transmission of HIV. To date, Africa is the only continent where an understanding of the impact of sexual concurrency has been conveyed in HIV prevention messaging. This project was developed by researchers and members of the Seattle, WA African American and African-Born communities, using the principles of community-based participatory research (CBPR). Interest in developing concurrency messaging came from the community and resulted in the successful submission of a community-academic partnership proposal to develop and disseminate HIV prevention messaging around concurrency. We describe: (a) the development of concurrency messaging through the integration of collected formative data and findings from the scientific literature; (b) the process of disseminating the message in the local Black community; and (c) important factors to consider in the development of similar campaigns. PMID:23206202

  18. Framing Effects in Narrative and Non-Narrative Risk Messages.

    PubMed

    Steinhardt, Joseph; Shapiro, Michael A

    2015-08-01

    Narrative messages are increasingly popular in health and risk campaigns, yet gain/loss framing effects have never been tested with such messages. Three experiments examined framing in narrative messages. Experiment 1 found that only the character's decision, not framing, influenced judgments about characters in a narrative derived from a prospect theory context. Experiment 2 found that a framing effect that occurred when presented in a decision format did not occur when the same situation was presented as a narrative. Using a different story/decision context, Experiment 3 found no significant difference in preference for surgery over radiation therapy in a narrative presentation compared to a non-narrative presentation. The results suggest that health and risk campaigns cannot assume that framing effects will be the same in narrative messages and non-narrative messages. Potential reasons for these differences and suggestions for future research are discussed. PMID:25809457

  19. Impact of nutrition messages on children's food choice: pilot study.

    PubMed

    Bannon, Katie; Schwartz, Marlene B

    2006-03-01

    This pilot study tested the influence of nutrition message framing on snack choice among kindergarteners. Three classrooms were randomly assigned to watch one of the following 60s videos: (a) a gain-framed nutrition message (i.e. the positive benefits of eating apples) (n=14); (b) a loss-framed message (i.e. the negative consequences of not eating apples) (n=18); or (c) a control scene (children playing a game) (n=18). Following this, the children were offered a choice between animal crackers and an apple for their snack. Among the children who saw one of the nutrition message videos, 56% chose apples rather than animal crackers; in the control condition only 33% chose apples. This difference was statistically significant (chi2=7.56, p<0.01). These results suggest that videos containing nutritional messages may have a positive influence on children's short-term food choices. PMID:16442667

  20. Creating buzz: the neural correlates of effective message propagation.

    PubMed

    Falk, Emily B; Morelli, Sylvia A; Welborn, B Locke; Dambacher, Karl; Lieberman, Matthew D

    2013-07-01

    Social interaction promotes the spread of values, attitudes, and behaviors. Here, we report on neural responses to ideas that are destined to spread. We scanned message communicators using functional MRI during their initial exposure to the to-be-communicated ideas. These message communicators then had the opportunity to spread the messages and their corresponding subjective evaluations to message recipients outside the scanner. Successful ideas were associated with neural responses in the communicators' mentalizing systems and reward systems when they first heard the messages, prior to spreading them. Similarly, individuals more able to spread their own views to others produced greater mentalizing-system activity during initial encoding. Unlike prior social-influence studies that focused on the individuals being influenced, this investigation focused on the brains of influencers. Successful social influence is reliably associated with an influencer-to-be's state of mind when first encoding ideas. PMID:23722983

  1. Flow of Emotional Messages in Artificial Social Networks

    NASA Astrophysics Data System (ADS)

    Chmiel, Anna; Hołyst, Janusz A.

    Models of message flows in an artificial group of users communicating via the Internet are introduced and investigated using numerical simulations. We assumed that messages possess an emotional character with a positive valence and that the willingness to send the next affective message to a given person increases with the number of messages received from this person. As a result, the weights of links between group members evolve over time. Memory effects are introduced, taking into account that the preferential selection of message receivers depends on the communication intensity during the recent period only. We also model the phenomenon of secondary social sharing when the reception of an emotional e-mail triggers the distribution of several emotional e-mails to other people.

  2. Vested interest, disaster preparedness, and strategic campaign message design.

    PubMed

    Adame, Bradley J; Miller, Claude H

    2015-01-01

    In recent years, the United States has recognized an increasing need for individual-level disaster preparedness, with federal, state, and local government agencies finding only limited success in instituting campaign-based disaster preparedness programs. Extant research indicates Americans generally remain poorly informed and badly unprepared for imminent disasters. Vested interest theory (Crano, 1997) is presented as a framework for designing and testing the effectiveness of television-based disaster preparedness campaign messages. High- and low-vested versions of an extant control message are compared to assess message efficacy as indicated by behavioral intentions, message acceptance, and preparedness related attitudes. Results indicate television-based video public service announcements manipulated with subtle message variations can be effective at influencing critical preparedness-related attitudes. The high-vested condition performed significantly better than the low-vested and control conditions for both behavioral intentions and perceptions of self-efficacy, two vitally important outcome variables associated with disaster preparedness. PMID:24837442

  3. Two-pass rate-distortion optimized rate control technique for H.264/AVC video

    NASA Astrophysics Data System (ADS)

    Lie, Wen-Nung; Chen, Chih-Fan; Lin, Tom C.

    2005-07-01

    Rate control for video encoders can be partitioned into procedures of rate allocation and bit achievement at several levels. For non-real-time applications, we propose to adopt a two-pass video encoding mechanism, where the framelevel rate allocation in the second pass is characterized of using content-aware models constructed by using information collected in the first pass. In our proposed scheme, a video sequence is divided into units of non-overlapping window, where a two-pass procedure is sequentially applied. The goal of the first pass is to find the encoding modes and motion vectors (MVs) for each MB and generate the proposed R-λ (rate vs. Lagrangian multiplier) and D-λ (distortion vs. Lagrangian multiplier) models to represent content characteristics of each frame. In the second pass, the encoding modes and MVs for MBs found in the first pass are retained, but the QPs are re-assigned MB-by-MB according to bit-rate and distortion predictions based on the above-constructed models. The performance of the proposed two-pass video encoder was compared with the H.264 reference model JM8.0. From the results, the proposed method outperforms JM 8.0 in PSNR by up to 1.38 dB for the test images used. Besides, the proposed algorithm is capable of keeping a controlled bit rate of much more precision (< 0.017% of error, two orders better than JM8.0), as well as a slightly smoother video quality, than that obtained by JM 8.0.

  4. Effect of Ball Mass on Dribble, Pass, and Pass Reception in 9-11-Year-Old Boys' Basketball

    ERIC Educational Resources Information Center

    Arias, Jose L.; Argudo, Francisco M.; Alonso, Jose I.

    2012-01-01

    The objective of the study was to analyze the effect of ball mass on dribble, pass, and pass reception in real game situations in 9-11-year-old boys' basketball. Participants were 54 boys identified from six federated teams. The independent variable was ball mass, and dependent variables were number of dribbles, passes, and pass receptions. Three…

  5. 78 FR 25432 - Sabine Pass LNG, L.P., Sabine Pass Liquefaction, LLC; Notice of Availability of the Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-01

    ... Energy Regulatory Commission Sabine Pass LNG, L.P., Sabine Pass Liquefaction, LLC; Notice of Availability of the Environmental Assessment for the Proposed Sabine Pass Liquefaction Project Modification The... assessment (EA) for the Sabine Pass Liquefaction Project Modification (Modification Project), proposed...

  6. 76 FR 9573 - Sabine Pass Liquefaction, LLC and Sabine Pass LNG, L.P.; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... Energy Regulatory Commission Sabine Pass Liquefaction, LLC and Sabine Pass LNG, L.P.; Notice of Application Take notice that on January 31, 2011, Sabine Pass Liquefaction, LLC and Sabine Pass LNG, L.P... the Commission's Regulations, to site, construct, and operate liquefaction and export...

  7. Algorithms for improved performance in cryptographic protocols.

    SciTech Connect

    Schroeppel, Richard Crabtree; Beaver, Cheryl Lynn

    2003-11-01

    Public key cryptographic algorithms provide data authentication and non-repudiation for electronic transmissions. The mathematical nature of the algorithms, however, means they require a significant amount of computation, and encrypted messages and digital signatures possess high bandwidth. Accordingly, there are many environments (e.g. wireless, ad-hoc, remote sensing networks) where public-key requirements are prohibitive and cannot be used. The use of elliptic curves in public-key computations has provided a means by which computations and bandwidth can be somewhat reduced. We report here on the research conducted in an LDRD aimed to find even more efficient algorithms and to make public-key cryptography available to a wider range of computing environments. We improved upon several algorithms, including one for which a patent has been applied. Further we discovered some new problems and relations on which future cryptographic algorithms may be based.

  8. Effect of Reinforcement of Oral Health Education Message through Short Messaging Service in Mobile Phones: A Quasi-Experimental Trial.

    PubMed

    Jadhav, Harish C; Dodamani, Arun S; Karibasappa, G N; Naik, Rahul G; Khairnar, Mahesh R; Deshmukh, Manjiri A; Vishwakarma, Prashanth

    2016-01-01

    Objective. This paper aims to assess the effectiveness of reinforcement of oral health education message through short messaging service (SMS) in mobile phones. Material and Methods. 400 subjects from two colleges (200 from each college) belonging to 18-20 years age group possessing mobile phones were randomly selected and baseline examination of oral hygiene and gingival status was carried out using Oral Hygiene Index (OHI) and Gingival Index (GI). Oral health education was provided to all the subjects. Oral health education message was reinforced through short messaging service (SMS) in mobile phones for the subjects belonging to the intervention group. There was no such reinforcement for the control group. Follow-up examinations were done at the end of 1st, 2nd, 3rd, and 6th month. After the 3rd month, subjects of the intervention group did not receive oral health education message through short messaging service (SMS) and were followed up after next three months. Compiled data was analyzed using SPSS version 16 statistical software. Result. Mean OHI and GI scores in intervention group were significantly (p < 0.01) less than those of control group after the 2nd, 3rd, and 6th month. Conclusion. Reinforcement of oral health education message through short messaging service (SMS) is effective media to improve oral health. PMID:26941793

  9. Effect of Reinforcement of Oral Health Education Message through Short Messaging Service in Mobile Phones: A Quasi-Experimental Trial

    PubMed Central

    Jadhav, Harish C.; Dodamani, Arun S.; Karibasappa, G. N.; Naik, Rahul G.; Khairnar, Mahesh R.; Deshmukh, Manjiri A.; Vishwakarma, Prashanth

    2016-01-01

    Objective. This paper aims to assess the effectiveness of reinforcement of oral health education message through short messaging service (SMS) in mobile phones. Material and Methods. 400 subjects from two colleges (200 from each college) belonging to 18–20 years age group possessing mobile phones were randomly selected and baseline examination of oral hygiene and gingival status was carried out using Oral Hygiene Index (OHI) and Gingival Index (GI). Oral health education was provided to all the subjects. Oral health education message was reinforced through short messaging service (SMS) in mobile phones for the subjects belonging to the intervention group. There was no such reinforcement for the control group. Follow-up examinations were done at the end of 1st, 2nd, 3rd, and 6th month. After the 3rd month, subjects of the intervention group did not receive oral health education message through short messaging service (SMS) and were followed up after next three months. Compiled data was analyzed using SPSS version 16 statistical software. Result. Mean OHI and GI scores in intervention group were significantly (p < 0.01) less than those of control group after the 2nd, 3rd, and 6th month. Conclusion. Reinforcement of oral health education message through short messaging service (SMS) is effective media to improve oral health. PMID:26941793

  10. Short Message Service (SMS) Texting Symbols: A Functional Analysis of 10,000 Cellular Phone Text Messages

    ERIC Educational Resources Information Center

    Beasley, Robert E.

    2009-01-01

    The purpose of this study was to investigate the use of symbolic expressions (e.g., "BTW," "LOL," "UR") in an SMS text messaging corpus consisting of over 10,000 text messages. More specifically, the purpose was to determine, not only how frequently these symbolic expressions are used, but how they are utilized in terms of the language functions…

  11. Scientific Message Translation and the Heuristic Systematic Model: Insights for Designing Educational Messages About Progesterone and Breast Cancer Risks.

    PubMed

    Hitt, Rose; Perrault, Evan; Smith, Sandi; Keating, David M; Nazione, Samantha; Silk, Kami; Russell, Jessica

    2016-06-01

    Results of ongoing scientific research on environmental determinants of breast cancer are not typically presented to the public in ways they can easily understand and use to take preventive actions. In this study, results of scientific studies on progesterone exposure as a risk factor for breast cancer were translated into high and low literacy level messages. Using the heuristic systematic model, this study examined how ability, motivation, and message processing (heuristic and systematic) influenced perceptions of risk beliefs and negative attitudes about progesterone exposure among women who read the translated scientific messages. Among the 1254 participants, those given the higher literacy level message had greater perceptions of risk about progesterone. Heuristic message cues of source credibility and perceived message quality, as well as motivation, also predicted risk beliefs. Finally, risk beliefs were a strong predictor of negative attitudes about exposure to progesterone. The results can help improve health education message design in terms of practitioners having better knowledge of message features that are the most persuasive to the target audiences on this topic. PMID:25903053

  12. Online Discussion Processes: Effects of Earlier Messages' Evaluations, Knowledge Content, Social Cues and Personal Information on Later Messages

    ERIC Educational Resources Information Center

    Chen, Gaowei; Chiu, Ming Ming

    2008-01-01

    This study of the flow of online discussions examined how earlier messages affected later messages along five dimensions: (1) evaluations (agreement, disagreement, or unresponsive actions); (2) knowledge content (contribution, repetition, or null content); (3) social cues (positive, negative, or none); (4) personal information (number of visits);…

  13. Students' Silent Messages: Can Teacher Verbal and Nonverbal Immediacy Moderate Student Use of Text Messaging in Class?

    ERIC Educational Resources Information Center

    Wei, Fang-Yi Flora; Wang, Y. Ken

    2010-01-01

    This study investigated the relationship between teacher immediacy and college students' use of text messaging in class. Using a cross-sectional survey sample (N=228), structural equation model analyses showed that students' learning motivation does not mediate the potential effects of teacher immediacy and students' use of text messaging in…

  14. Application of Feedforward Adaptive Active-Noise Control for Reducing Blade Passing Noise in Centrifugal Fans

    NASA Astrophysics Data System (ADS)

    WU, J.-D.; BAI, M. R.

    2001-02-01

    This paper describes two configurations of feedforward adaptive active-noise control (ANC) technique for reducing blade passing noise in centrifugal fans. In one configuration, the control speaker is installed at the cut-off region of the fan, while in the other configuration at the exit duct. The proposed ANC system is based on the filtered-x least-mean-squares (FXLMS) algorithm with multi-sine synthesized reference signal and frequency counting and is implemented by using a digital signal processor (DSP). Experiments are carried out to evaluate the proposed system for reducing the noise at the blade passing frequency (BPF) and its harmonics at various flow speeds. The results of the experiment indicated that the ANC technique is effective in reducing the blade passing noise for two configurations by using the feedforward adaptive control.

  15. Multichannel, Active Low-Pass Filters

    NASA Technical Reports Server (NTRS)

    Lev, James J.

    1989-01-01

    Multichannel integrated circuits cascaded to obtain matched characteristics. Gain and phase characteristics of channels of multichannel, multistage, active, low-pass filter matched by making filter of cascaded multichannel integrated-circuit operational amplifiers. Concept takes advantage of inherent equality of electrical characteristics of nominally-identical circuit elements made on same integrated-circuit chip. Characteristics of channels vary identically with changes in temperature. If additional matched channels needed, chips containing more than two operational amplifiers apiece (e.g., commercial quad operational amplifliers) used. Concept applicable to variety of equipment requiring matched gain and phase in multiple channels - radar, test instruments, communication circuits, and equipment for electronic countermeasures.

  16. Pass-transistor asynchronous sequential circuits

    NASA Astrophysics Data System (ADS)

    Whitaker, Sterling R.; Maki, Gary K.

    1989-02-01

    Design methods for asynchronous sequential pass-transistor circuits, which result in circuits that are hazard- and critical-race-free and which have added degrees of freedom for the input signals, are discussed. The design procedures are straightforward and easy to implement. Two single-transition-time state assignment methods are presented, and hardware bounds for each are established. A surprising result is that the hardware realizations for each next state variable and output variable is identical for a given flow table. Thus, a state machine with N states and M outputs can be constructed using a single layout replicated N + M times.

  17. Quantum three-pass cryptography protocol

    NASA Astrophysics Data System (ADS)

    Yang, Li; Wu, Ling-An; Liu, Songhao

    2002-09-01

    We present a new kind of quantum cryptography protocol based on Shamir's three-pass protocol of classical cryptography, which allows the transmission of qubits directly and secretly via the aid of an unjammable classical channel. In this protocol we implement the encryption and decryption transformations via rotations on the Poincare sphere of the photons polarization parameters. The key technique is that Bob's encryption rotation must be commutative with Alice s decryption rotation; this means that the axes of these two rotations must be parallel. We also present a security analysis of the protocol under a man-in-the-middle attack.

  18. Fabrication of seamless calandria tubes by cold pilgering route using 3-pass and 2-pass schedules

    NASA Astrophysics Data System (ADS)

    Saibaba, N.

    2008-12-01

    Calandria tube is a large diameter, extremely thin walled zirconium alloy tube which has diameter to wall thickness ratio as high as 90-95. Such tubes are conventionally produced by the 'welded route', which involves extrusion of slabs followed by a series of hot and cold rolling passes, intermediate anneals, press forming of sheets into circular shape and closing the gap by TIG welding. Though pilgering is a well established process for the fabrication of seamless tubes, production of extremely thin walled tubes offers several challenges during pilgering. Nuclear fuel complex (NFC), Hyderabad, has successfully developed a process for the production of Zircaloy-4 calandria tubes by adopting the 'seamless route' which involves hot extrusion of mother blanks followed by three-pass pilgering or two-pass pilgering schedules. This paper deals with standardization of the seamless route processes for fabrication of calandria tubes, comparison between the tubes produced by 2-pass and 3-pass pilgering schedules, role of ultrasonic test charts for control of process parameters, development of new testing methods for burst testing and other properties.

  19. Psychology in health risk messages for workers.

    PubMed

    Cohen, A; Colligan, M J; Berger, P

    1985-08-01

    The content, style, and mode of company communications directed to workers regarding job hazards and health risks are frequently based only on concerns for technical accuracy and legal liability. These considerations as shaping factors in informational messages do not ensure worker understanding and responsiveness. Moreover, the uncertainty of health threats posed by many workplace chemical and physical agents, and the delayed, insidious disorders they may portend, present formidable obstacles in this regard. This report describes guidelines that attempt to overcome these difficulties, with specific reference to printed forms of informational material. The guidelines are based on concepts from the cognitive and social psychology literature, with additional input from experts in those fields as well as representatives from management and labor who have responsibilities for worker health education in their respective organizations. Selected guidelines are presented and critiques are offered of samples of hazard information materials directed to workers in light of the guidelines' prescriptions. Field trials are planned as a follow-up. PMID:4032089

  20. WHO KILLED LAIUS?: ON SOPHOCLES' ENIGMATIC MESSAGE.

    PubMed

    Priel, Beatriz

    2002-04-01

    Using Laplanche's basic conceptualisation of the role of the other in unconscious processes, the author proposes a reading of Sophocles' tragedy, Oedipus the King, according to basic principles of dream interpretation. This reading corroborates contemporary literary perspectives suggesting that Sophocles' tragedy may not only convey the myth but also provide a critical analysis of how myths work. Important textual inconsistencies and incoherence, which have been noted through the centuries, suggest the existence of another, repressed story. Moreover, the action of the play points to enigmatic parental messages of infanticide and the silencing of Oedipus's story, as well as their translation into primordial guilt, as the origins of the tragic denouement. Oedipus's self-condemnation of parricide follows these enigmatic codes and is unrelated to, and may even contradict, the evidence offered in the tragedy as to the identity of Laius's murderers. Moreover, Sophocles' text provides a complex intertwining of hermeneutic and deterministic perspectives. Through the use of the mythical deterministic content, the formal characteristics of Sophocles' text, mainly its complex time perspective and extensive use of double meaning, dramatise in the act of reading an acute awareness of interpretation. This reading underscores the fundamental role of the other in the constitution of unconscious processes. PMID:12028701

  1. Who killed Laius?: On Sophocles' enigmatic message.

    PubMed

    Priel, Beatriz

    2002-04-01

    Using Laplanche's basic conceptualisation of the role of the other in unconscious processes, the author proposes a reading of Sophocles' tragedy, Oedipus the King, according to basic principles of dream interpretation. This reading corroborates contemporary literary perspectives suggesting that Sophocles' tragedy may not only convey the myth but also provide a critical analysis of how myths work. Important textual inconsistencies and incoherence, which have been noted through the centuries, suggest the existence of another, repressed story. Moreover, the action of the play points to enigmatic parental messages of infanticide and the silencing of Oedipus's story, as well as their translation into primordial guilt, as the origins of the tragic denouement. Oedipus's self-condemnation of parricide follows these enigmatic codes and is unrelated to, and may even contradict, the evidence offered in the tragedy as to the identity of Laius's murderers. Moreover, Sophocles' text provides a complex intertwining of hermeneutic and deterministic perspectives. Through the use of the mythical deterministic content, the formal characteristics of Sophocles' text, mainly its complex time perspective and extensive use of double meaning, dramatise in the act of reading an acute awareness of interpretation. This reading underscores the fundamental role of the other in the constitution of unconscious processes. PMID:12040706

  2. Brave message from a dead Bhundu Boy.

    PubMed

    Meldrum, A

    The death of David Mankaba, one of Zimbabwe's top pop stars, from AIDS is expected to increase the country's awareness regarding the dangers of the disease. Mankaba is the bass guitarist of The Bhundu Boys whose "Jit" music is popular in both England and US. He was diagnosed to have tuberculosis and was later found to have AIDS. Before his death, he requested for his family to announce to the public that he had died from AIDS. This made him the first well-known Zimbabwean to declare that he is infected with the HIV virus in a country that continues to ignore the threat from AIDS despite its 9000 full-blown cases and an estimated 500,000 to over a million HIV-positive individuals. Mankaba's message is expected to play a major role in educating Zimbabweans against casual, unprotected sex and encourage them to take education campaigns more seriously. Furthermore, Mankaba's announcement is important considering that public awareness campaigns have been shown to be more effective when supported by first hand knowledge of people with AIDS. PMID:12295501

  3. A Vondrak low pass filter for IMU sensor initial alignment on a disturbed base.

    PubMed

    Li, Zengke; Wang, Jian; Gao, Jingxiang; Li, Binghao; Zhou, Feng

    2014-01-01

    The initial alignment of the Inertial Measurement Unit (IMU) is an important process of INS to determine the coordinate transformation matrix which is used in the integration of Global Positioning Systems (GPS) with Inertial Navigation Systems (INS). In this paper a novel alignment method for a disturbed base, such as a vehicle disturbed by wind outdoors, implemented with the aid of a Vondrak low pass filter, is proposed. The basic principle of initial alignment including coarse alignment and fine alignment is introduced first. The spectral analysis is processed to compare the differences between the characteristic error of INS force observation on a stationary base and on disturbed bases. In order to reduce the high frequency noise in the force observation more accurately and more easily, a Vondrak low pass filter is constructed based on the spectral analysis result. The genetic algorithms method is introduced to choose the smoothing factor in the Vondrak filter and the corresponding objective condition is built. The architecture of the proposed alignment method with the Vondrak low pass filter is shown. Furthermore, simulated experiments and actual experiments were performed to validate the new algorithm. The results indicate that, compared with the conventional alignment method, the Vondrak filter could eliminate the high frequency noise in the force observation and the proposed alignment method could improve the attitude accuracy. At the same time, only one parameter needs to be set, which makes the proposed method easier to implement than other low-pass filter methods. PMID:25513826

  4. A Vondrak Low Pass Filter for IMU Sensor Initial Alignment on a Disturbed Base

    PubMed Central

    Li, Zengke; Wang, Jian; Gao, Jingxiang; Li, Binghao; Zhou, Feng

    2014-01-01

    The initial alignment of the Inertial Measurement Unit (IMU) is an important process of INS to determine the coordinate transformation matrix which is used in the integration of Global Positioning Systems (GPS) with Inertial Navigation Systems (INS). In this paper a novel alignment method for a disturbed base, such as a vehicle disturbed by wind outdoors, implemented with the aid of a Vondrak low pass filter, is proposed. The basic principle of initial alignment including coarse alignment and fine alignment is introduced first. The spectral analysis is processed to compare the differences between the characteristic error of INS force observation on a stationary base and on disturbed bases. In order to reduce the high frequency noise in the force observation more accurately and more easily, a Vondrak low pass filter is constructed based on the spectral analysis result. The genetic algorithms method is introduced to choose the smoothing factor in the Vondrak filter and the corresponding objective condition is built. The architecture of the proposed alignment method with the Vondrak low pass filter is shown. Furthermore, simulated experiments and actual experiments were performed to validate the new algorithm. The results indicate that, compared with the conventional alignment method, the Vondrak filter could eliminate the high frequency noise in the force observation and the proposed alignment method could improve the attitude accuracy. At the same time, only one parameter needs to be set, which makes the proposed method easier to implement than other low-pass filter methods. PMID:25513826

  5. High speed polling protocol for multiple node network with sequential flooding of a polling message and a poll-answering message

    NASA Technical Reports Server (NTRS)

    Marvit, Maclen (Inventor); Kirkham, Harold (Inventor)

    1995-01-01

    The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs a remote node polling process performed by a master node by transmitting a polling message generically addressed to all remote nodes associated with the master node. Each remote node responds upon receipt of the generically addressed polling message by sequentially flooding the network with a poll-answering informational message and with the polling message.

  6. ABM Drag_Pass Report Generator

    NASA Technical Reports Server (NTRS)

    Fisher, Forest; Gladden, Roy; Khanampornpan, Teerapat

    2008-01-01

    dragREPORT software was developed in parallel with abmREPORT, which is described in the preceding article. Both programs were built on the capabilities created during that process. This tool generates a drag_pass report that summarizes vital information from the MRO aerobreaking drag_pass build process to facilitate both sequence reviews and provide a high-level summarization of the sequence for mission management. The script extracts information from the ENV, SSF, FRF, SCMFmax, and OPTG files, presenting them in a single, easy-to-check report providing the majority of parameters needed for cross check and verification as part of the sequence review process. Prior to dragReport, all the needed information was spread across a number of different files, each in a different format. This software is a Perl script that extracts vital summarization information and build-process details from a number of source files into a single, concise report format used to aid the MPST sequence review process and to provide a high-level summarization of the sequence for mission management reference. This software could be adapted for future aerobraking missions to provide similar reports, review and summarization information.

  7. Personalised electronic messages to improve sun protection in young adults.

    PubMed

    Mair, Sarah; Soyer, H Peter; Youl, Philippa; Hurst, Cameron; Marshall, Alison; Janda, Monika

    2012-07-01

    We studied the acceptability and feasibility of delivering sun protection messages via electronic media such as short message services (SMS) to people aged 18-40 years. An online survey was conducted using a pre-established panel of volunteers. We compared the characteristics of those who indicated that they would like to be alerted to the UV index, with those who would not, using bivariate logistic regression. Characteristics found to be associated with a desire to receive such advice were entered into a multivariate logistic regression analysis. The median age of the 141 participants was 34 years. Overall, 80% of participants agreed that they would like to receive some form of sun protection advice. Of these, 20% preferred to receive it via SMS and 42% via email. Willingness to receive electronic messages about the UV index was associated with being unsure about whether a suntanned person would look healthy and greater use of sun protection in the past. Careful attention to message framing and timing of message delivery, and focus on the short-term effects of sun exposure such as sunburn and skin ageing should increase the acceptability of such messages to young people. Sun protection messages delivered to young adults via electronic media appear to be feasible and acceptable. PMID:22302765

  8. Loop transformations for performance and message latency hiding in parallel object-oriented frameworks

    SciTech Connect

    Bassetti, F.; Davis, K.; Quinlan, D.

    1998-09-01

    Application codes reliably achieve performance far less than the advertised capabilities of existing architectures, and this problem is worsening with increasingly-parallel machines. For large-scale numerical applications, stencil operations often impose the greater part of the computational cost, and the primary sources of inefficiency are the costs of message passing and poor cache utilization. This paper proposes and demonstrates optimizations for stencil and stencil-like computations for both serial and parallel environments that ameliorate these sources of inefficiency. Additionally, the authors argue that when stencil-like computations are encoded at a high level using object-oriented parallel array class libraries these optimizations, which are beyond the capability of compilers, may be automated.

  9. An Introduction to Message-Bus Architectures for Space Systems

    NASA Technical Reports Server (NTRS)

    Smith, Danford; Gregory, Brian

    2005-01-01

    This course presents technical and programmatic information on the development of message-based architectures for space mission ground and flight software systems. Message-based architecture approaches provide many significant advantages over the more traditional socket-based one-of-a-kind integrated system development approaches. The course provides an overview of publish/subscribe concepts, the use of common isolation layer API's, approaches to message standardization, and other technical topics. Several examples of currently operational systems are discussed and possible changes to the system discussed and time for questions and answers will be provided.

  10. Introduction to Message-Bus Architectures for Space Systems

    NASA Technical Reports Server (NTRS)

    Smith, Dan; Gregory, Brian

    2005-01-01

    This course presents technical and programmatic information on the development of message-based architectures for space mission ground and flight software systems. Message-based architecture approaches provide many significant advantages over the more traditional socket-based one-of-a-kind integrated system development approaches. The course provides an overview of publish/subscribe concepts, the use of common isolation layer API's, approaches to message standardization, and other technical topics. Several examples of currently operational systems are discussed and possible changes to the system development process are presented. Benefits and lessons learned will be discussed and time for questions and answers will be provided.

  11. Packet message communication system using polar orbiting small satellites

    NASA Astrophysics Data System (ADS)

    Suzuki, Ryutaro; Suzuki, Yoshiaki; Arimoto, Yoshinori; Ohmori, Shingo; Kondo, Kimio

    A packet message communication system using small satellites is studied for the worldwide electronic mail type communications. A store and forward type packet communication equipment is installed in a small satellite which rotates in the polar orbit. By using the inter satellite link among the small satellites and/or the data exchange earth station in the polar region, the delay time of the packet message delivery can be shortened. The multibeam phased array technique is applied for the satellite antenna in order to increase the link quality. Four satellites configuration gives a 4.8 kbps data rate message with less than two hours of delay.

  12. An Efficient, Scalable Content-Based Messaging System

    SciTech Connect

    Gorton, Ian; Almquist, Justin P.; Cramer, Nick O.; Haack, Jereme N.; Hoza, Mark

    2003-09-16

    Large-scale information processing environments must rapidly search through massive streams of raw data to locate useful information. These data streams contain textual and numeric data items, and may be highly structured or mostly freeform text. This project aims to create a high performance and scalable engine for locating relevant content in data streams. Based on the J2EE Java Messaging Service (JMS), the content-based messaging (CBM) engine provides highly efficient message formatting and filtering. This paper describes the design of the CBM engine, and presents empirical results that compare the performance with a standard JMS to demonstrate the performance improvements that are achieved.

  13. Students' state motivation and instructors' use of verbally aggressive messages.

    PubMed

    Myers, S A; Rocca, K A

    2000-08-01

    This study examined the relationship between college students' (107 men, 123 women) state motivation and their instructors' perceived use of 10 verbally aggressive messages, e.g., attacks on competence, character, background, and physical appearance; malediction, teasing, ridicule, threats, swearing, or nonverbal symbols. Significant negative correlations were obtained between students' state motivation and instructors' use of seven verbally aggressive messages: attacks on competence, character, or background, malediction, ridicule, threats, and nonverbal symbols. These findings suggest that these types of verbally aggressive messages are related to students' state motivation whereas attacks on physical appearance, teasing, and swearing by the instructor are not related to students' state motivation. PMID:11026427

  14. Bathymetric survey of the nearshore from Belle Pass to Caminada Pass, Louisiana: methods and data report

    USGS Publications Warehouse

    DeWitt, Nancy T.; Flocks, James G.; Hansen, Mark; Kulp, Mark; Reynolds, B.J.

    2007-01-01

    The U.S. Geological Survey (USGS), in cooperation with the University of New Orleans (UNO) and the Louisiana Department of Natural Resources (LDNR), conducted a high-resolution, single-beam bathymetric survey along the Louisiana southern coastal zone from Belle Pass to Caminada Pass. The survey consisted of 483 line kilometers of data acquired in July and August of 2005. This report outlines the methodology and provides the data from the survey. Analysis of the data and comparison to a similar bathymetric survey completed in 1989 show significant loss of seafloor and shoreline retreat, which is consistent with previously published estimates of shoreline change in the study area.

  15. 48 CFR 52.223-18 - Encouraging Contractor Policies To Ban Text Messaging While Driving.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... short message service texting, e-mailing, instant messaging, obtaining navigational information, or... the safety risks associated with texting while driving. (d) Subcontracts. The Contractor shall...

  16. 48 CFR 52.223-18 - Encouraging Contractor Policies To Ban Text Messaging While Driving.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... short message service texting, e-mailing, instant messaging, obtaining navigational information, or... the safety risks associated with texting while driving. (d) Subcontracts. The Contractor shall...

  17. 48 CFR 52.223-18 - Encouraging Contractor Policies To Ban Text Messaging While Driving.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... short message service texting, e-mailing, instant messaging, obtaining navigational information, or... the safety risks associated with texting while driving. (d) Subcontracts. The Contractor shall...

  18. 48 CFR 52.223-18 - Encouraging Contractor Policies To Ban Text Messaging While Driving.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... short message service texting, e-mailing, instant messaging, obtaining navigational information, or... the safety risks associated with texting while driving. (d) Subcontracts. The Contractor shall...

  19. Quantum algorithms

    NASA Astrophysics Data System (ADS)

    Abrams, Daniel S.

    This thesis describes several new quantum algorithms. These include a polynomial time algorithm that uses a quantum fast Fourier transform to find eigenvalues and eigenvectors of a Hamiltonian operator, and that can be applied in cases (commonly found in ab initio physics and chemistry problems) for which all known classical algorithms require exponential time. Fast algorithms for simulating many body Fermi systems are also provided in both first and second quantized descriptions. An efficient quantum algorithm for anti-symmetrization is given as well as a detailed discussion of a simulation of the Hubbard model. In addition, quantum algorithms that calculate numerical integrals and various characteristics of stochastic processes are described. Two techniques are given, both of which obtain an exponential speed increase in comparison to the fastest known classical deterministic algorithms and a quadratic speed increase in comparison to classical Monte Carlo (probabilistic) methods. I derive a simpler and slightly faster version of Grover's mean algorithm, show how to apply quantum counting to the problem, develop some variations of these algorithms, and show how both (apparently distinct) approaches can be understood from the same unified framework. Finally, the relationship between physics and computation is explored in some more depth, and it is shown that computational complexity theory depends very sensitively on physical laws. In particular, it is shown that nonlinear quantum mechanics allows for the polynomial time solution of NP-complete and #P oracle problems. Using the Weinberg model as a simple example, the explicit construction of the necessary gates is derived from the underlying physics. Nonlinear quantum algorithms are also presented using Polchinski type nonlinearities which do not allow for superluminal communication. (Copies available exclusively from MIT Libraries, Rm. 14- 0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  20. Apollo 11 Lunar Message For Mankind- Reproduction

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Millions of people on Earth watched via television as a message for all mankind was delivered to the Mare Tranquilitatis (Sea of Tranquility) region of the Moon during the historic Apollo 11 mission, where it still remains today. This photograph is a reproduction of the commemorative plaque that was attached to the leg of the Lunar Module (LM), Eagle, engraved with the following words: 'Here men from the planet Earth first set foot upon the Moon July, 1969 A.D. We came in peace for all of mankind.' It bears the signatures of the Apollo 11 astronauts Neil A. Armstrong, commander; Michael Collins, Command Module (CM) pilot; and Edwin E. Aldrin, Jr., Lunar Module (LM) pilot along with the signature of the U.S. President Richard M. Nixon. The Apollo 11 mission launched from the Kennedy Space Center (KSC) in Florida via the Marshall Space Flight Center (MSFC) developed Saturn V launch vehicle on July 16, 1969 and safely returned to Earth on July 24, 1969. The CM, 'Columbia', piloted by Collins, remained in a parking orbit around the Moon while the LM, 'Eagle'', carrying astronauts Armstrong and Aldrin, landed on the Moon. On July 20, 1969, Armstrong was the first human to ever stand on the lunar surface, followed by Aldrin. During 2½ hours of surface exploration, the crew collected 47 pounds of lunar surface material for analysis back on Earth. With the success of Apollo 11, the national objective to land men on the Moon and return them safely to Earth had been accomplished.