Communications oriented programming of parallel iterative solutions of sparse linear systems

NASA Technical Reports Server (NTRS)

Patrick, M. L.; Pratt, T. W.

1986-01-01

Parallel algorithms are developed for a class of scientific computational problems by partitioning the problems into smaller problems which may be solved concurrently. The effectiveness of the resulting parallel solutions is determined by the amount and frequency of communication and synchronization and the extent to which communication can be overlapped with computation. Three different parallel algorithms for solving the same class of problems are presented, and their effectiveness is analyzed from this point of view. The algorithms are programmed using a new programming environment. Run-time statistics and experience obtained from the execution of these programs assist in measuring the effectiveness of these algorithms.

Reply to Comments.

PubMed

Sripada, Chandra; Railton, Peter; Baumeister, Roy F; Seligman, Martin E P

2013-03-01

Evidence of prospective processes is increasingly common in psychological research, which suggests the fruitfulness of a theoretical framework for mind and brain built around future orientation. No metaphysics of determinism or indeterminism is presupposed by this framework, nor do considerations of scientific method require determinism-successful scientific theories in the natural sciences all involve probabilistic elements. We speculate that expressive behavior and moral decision making use prospective processes parallel to those used in nonmoral decisions. © The Author(s) 2013.

An outline of object-oriented philosophy.

PubMed

Harman, Graham

2013-01-01

This article summarises the principles of object-oriented philosophy and explains its similarities with, and differences from, the outlook of the natural sciences. Like science, the object-oriented position avoids the notion (quite common in philosophy) that the human-world relation is the ground of all others, such that scientific statements about the world would only be statements about the world as it is for humans. But unlike science, object-oriented metaphysics treats artificial, social, and fictional entities in the same way as natural ones, and also holds that the world can only be known allusively rather than directly.

Synchronous Parallel Emulation and Discrete Event Simulation System with Self-Contained Simulation Objects and Active Event Objects

NASA Technical Reports Server (NTRS)

Steinman, Jeffrey S. (Inventor)

1998-01-01

The present invention is embodied in a method of performing object-oriented simulation and a system having inter-connected processor nodes operating in parallel to simulate mutual interactions of a set of discrete simulation objects distributed among the nodes as a sequence of discrete events changing state variables of respective simulation objects so as to generate new event-defining messages addressed to respective ones of the nodes. The object-oriented simulation is performed at each one of the nodes by assigning passive self-contained simulation objects to each one of the nodes, responding to messages received at one node by generating corresponding active event objects having user-defined inherent capabilities and individual time stamps and corresponding to respective events affecting one of the passive self-contained simulation objects of the one node, restricting the respective passive self-contained simulation objects to only providing and receiving information from die respective active event objects, requesting information and changing variables within a passive self-contained simulation object by the active event object, and producing corresponding messages specifying events resulting therefrom by the active event objects.

Mentat: An object-oriented macro data flow system

NASA Technical Reports Server (NTRS)

Grimshaw, Andrew S.; Liu, Jane W. S.

1988-01-01

Mentat, an object-oriented macro data flow system designed to facilitate parallelism in distributed systems, is presented. The macro data flow model is a model of computation similar to the data flow model with two principal differences: the computational complexity of the actors is much greater than in traditional data flow systems, and there are persistent actors that maintain state information between executions. Mentat is a system that combines the object-oriented programming paradigm and the macro data flow model of computation. Mentat programs use a dynamic structure called a future list to represent the future of computations.

Geopotential Error Analysis from Satellite Gradiometer and Global Positioning System Observables on Parallel Architecture

NASA Technical Reports Server (NTRS)

Schutz, Bob E.; Baker, Gregory A.

1997-01-01

The recovery of a high resolution geopotential from satellite gradiometer observations motivates the examination of high performance computational techniques. The primary subject matter addresses specifically the use of satellite gradiometer and GPS observations to form and invert the normal matrix associated with a large degree and order geopotential solution. Memory resident and out-of-core parallel linear algebra techniques along with data parallel batch algorithms form the foundation of the least squares application structure. A secondary topic includes the adoption of object oriented programming techniques to enhance modularity and reusability of code. Applications implementing the parallel and object oriented methods successfully calculate the degree variance for a degree and order 110 geopotential solution on 32 processors of the Cray T3E. The memory resident gradiometer application exhibits an overall application performance of 5.4 Gflops, and the out-of-core linear solver exhibits an overall performance of 2.4 Gflops. The combination solution derived from a sun synchronous gradiometer orbit produce average geoid height variances of 17 millimeters.

Geopotential error analysis from satellite gradiometer and global positioning system observables on parallel architectures

NASA Astrophysics Data System (ADS)

Baker, Gregory Allen

The recovery of a high resolution geopotential from satellite gradiometer observations motivates the examination of high performance computational techniques. The primary subject matter addresses specifically the use of satellite gradiometer and GPS observations to form and invert the normal matrix associated with a large degree and order geopotential solution. Memory resident and out-of-core parallel linear algebra techniques along with data parallel batch algorithms form the foundation of the least squares application structure. A secondary topic includes the adoption of object oriented programming techniques to enhance modularity and reusability of code. Applications implementing the parallel and object oriented methods successfully calculate the degree variance for a degree and order 110 geopotential solution on 32 processors of the Cray T3E. The memory resident gradiometer application exhibits an overall application performance of 5.4 Gflops, and the out-of-core linear solver exhibits an overall performance of 2.4 Gflops. The combination solution derived from a sun synchronous gradiometer orbit produce average geoid height variances of 17 millimeters.

Parallelization of an Object-Oriented Unstructured Aeroacoustics Solver

NASA Technical Reports Server (NTRS)

Baggag, Abdelkader; Atkins, Harold; Oezturan, Can; Keyes, David

1999-01-01

A computational aeroacoustics code based on the discontinuous Galerkin method is ported to several parallel platforms using MPI. The discontinuous Galerkin method is a compact high-order method that retains its accuracy and robustness on non-smooth unstructured meshes. In its semi-discrete form, the discontinuous Galerkin method can be combined with explicit time marching methods making it well suited to time accurate computations. The compact nature of the discontinuous Galerkin method also makes it well suited for distributed memory parallel platforms. The original serial code was written using an object-oriented approach and was previously optimized for cache-based machines. The port to parallel platforms was achieved simply by treating partition boundaries as a type of boundary condition. Code modifications were minimal because boundary conditions were abstractions in the original program. Scalability results are presented for the SCI Origin, IBM SP2, and clusters of SGI and Sun workstations. Slightly superlinear speedup is achieved on a fixed-size problem on the Origin, due to cache effects.

Perception Of "Features" And "Objects": Applications To The Design Of Instrument Panel Displays

NASA Astrophysics Data System (ADS)

Poynter, Douglas; Czarnomski, Alan J.

1988-10-01

An experiment was conducted to determine whether socalled feature displays allow for faster and more accurate processing compared to object displays. Previous psychological studies indicate that features can be processed in parallel across the visual field, whereas objects must be processed one at a time with the aid of attentional focus. Numbers and letters are examples of objects; line orientation and color are examples of features. In this experiment, subjects were asked to search displays composed of up to 16 elements for the presence of specific elements. The ability to detect, localize, and identify targets was influenced by display format. Digital errors increased with the number of elements, the number of targets, and the distance of the target from the fixation point. Line orientation errors increased only with the number of targets. Several other display types were evaluated, and each produced a pattern of errors similar to either digital or line orientation format. Results of the study were discussed in terms of Feature Integration Theory, which distinguishes between elements that are processed with parallel versus serial mechanisms.

PFLOTRAN User Manual: A Massively Parallel Reactive Flow and Transport Model for Describing Surface and Subsurface Processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lichtner, Peter C.; Hammond, Glenn E.; Lu, Chuan

PFLOTRAN solves a system of generally nonlinear partial differential equations describing multi-phase, multicomponent and multiscale reactive flow and transport in porous materials. The code is designed to run on massively parallel computing architectures as well as workstations and laptops (e.g. Hammond et al., 2011). Parallelization is achieved through domain decomposition using the PETSc (Portable Extensible Toolkit for Scientific Computation) libraries for the parallelization framework (Balay et al., 1997). PFLOTRAN has been developed from the ground up for parallel scalability and has been run on up to 218 processor cores with problem sizes up to 2 billion degrees of freedom. Writtenmore » in object oriented Fortran 90, the code requires the latest compilers compatible with Fortran 2003. At the time of this writing this requires gcc 4.7.x, Intel 12.1.x and PGC compilers. As a requirement of running problems with a large number of degrees of freedom, PFLOTRAN allows reading input data that is too large to fit into memory allotted to a single processor core. The current limitation to the problem size PFLOTRAN can handle is the limitation of the HDF5 file format used for parallel IO to 32 bit integers. Noting that 2 32 = 4; 294; 967; 296, this gives an estimate of the maximum problem size that can be currently run with PFLOTRAN. Hopefully this limitation will be remedied in the near future.« less

Object-oriented structures supporting remote sensing databases

NASA Technical Reports Server (NTRS)

Wichmann, Keith; Cromp, Robert F.

1995-01-01

Object-oriented databases show promise for modeling the complex interrelationships pervasive in scientific domains. To examine the utility of this approach, we have developed an Intelligent Information Fusion System based on this technology, and applied it to the problem of managing an active repository of remotely-sensed satellite scenes. The design and implementation of the system is compared and contrasted with conventional relational database techniques, followed by a presentation of the underlying object-oriented data structures used to enable fast indexing into the data holdings.

Predicted variation of stress orientation with depth near an active fault: application to the Cajon Pass Scientific Drillhole, southern California

USGS Publications Warehouse

Wesson, R.L.

1988-01-01

Preliminary measurements of the stress orientation at a depth of 2 km interpreted to indicate that the regional orientation of the maximum compression is normal to the fault, and taken as evidence for a very weak fault. The orientation expected from plate tectonic arguments is about 66?? NE from the strike of the fault. Geodetic data indicate that the orientation of maximum compressive strain rate is about 43?? NE from the strike of the fault, and show nearly pure right-lateral shear acting parallel to the fault. These apparent conflicts in the inferred orientation of the axis of maximum compression may be explained in part by a model in which the fault zone is locked over a depth interval in the range of 2-5 to 15 km, but is very weak above and below that interval. This solution does require, however, a few mm/yr of creep at the surface on the San Andreas or nearby sub-parallel faults (such as the San Jacinto), which has not yet been observed, or a shallow zone near the faults of distributed deformation. -from Author

Implementing an Affordable High-Performance Computing for Teaching-Oriented Computer Science Curriculum

ERIC Educational Resources Information Center

Abuzaghleh, Omar; Goldschmidt, Kathleen; Elleithy, Yasser; Lee, Jeongkyu

2013-01-01

With the advances in computing power, high-performance computing (HPC) platforms have had an impact on not only scientific research in advanced organizations but also computer science curriculum in the educational community. For example, multicore programming and parallel systems are highly desired courses in the computer science major. However,…

WFIRST: Science from the Guest Investigator and Parallel Observation Programs

NASA Astrophysics Data System (ADS)

Postman, Marc; Nataf, David; Furlanetto, Steve; Milam, Stephanie; Robertson, Brant; Williams, Ben; Teplitz, Harry; Moustakas, Leonidas; Geha, Marla; Gilbert, Karoline; Dickinson, Mark; Scolnic, Daniel; Ravindranath, Swara; Strolger, Louis; Peek, Joshua; Marc Postman

2018-01-01

The Wide Field InfraRed Survey Telescope (WFIRST) mission will provide an extremely rich archival dataset that will enable a broad range of scientific investigations beyond the initial objectives of the proposed key survey programs. The scientific impact of WFIRST will thus be significantly expanded by a robust Guest Investigator (GI) archival research program. We will present examples of GI research opportunities ranging from studies of the properties of a variety of Solar System objects, surveys of the outer Milky Way halo, comprehensive studies of cluster galaxies, to unique and new constraints on the epoch of cosmic re-ionization and the assembly of galaxies in the early universe.WFIRST will also support the acquisition of deep wide-field imaging and slitless spectroscopic data obtained in parallel during campaigns with the coronagraphic instrument (CGI). These parallel wide-field imager (WFI) datasets can provide deep imaging data covering several square degrees at no impact to the scheduling of the CGI program. A competitively selected program of well-designed parallel WFI observation programs will, like the GI science above, maximize the overall scientific impact of WFIRST. We will give two examples of parallel observations that could be conducted during a proposed CGI program centered on a dozen nearby stars.

Parallel Implementation of Triangular Cellular Automata for Computing Two-Dimensional Elastodynamic Response on Arbitrary Domains

NASA Astrophysics Data System (ADS)

Leamy, Michael J.; Springer, Adam C.

In this research we report parallel implementation of a Cellular Automata-based simulation tool for computing elastodynamic response on complex, two-dimensional domains. Elastodynamic simulation using Cellular Automata (CA) has recently been presented as an alternative, inherently object-oriented technique for accurately and efficiently computing linear and nonlinear wave propagation in arbitrarily-shaped geometries. The local, autonomous nature of the method should lead to straight-forward and efficient parallelization. We address this notion on symmetric multiprocessor (SMP) hardware using a Java-based object-oriented CA code implementing triangular state machines (i.e., automata) and the MPI bindings written in Java (MPJ Express). We use MPJ Express to reconfigure our existing CA code to distribute a domain's automata to cores present on a dual quad-core shared-memory system (eight total processors). We note that this message passing parallelization strategy is directly applicable to computer clustered computing, which will be the focus of follow-on research. Results on the shared memory platform indicate nearly-ideal, linear speed-up. We conclude that the CA-based elastodynamic simulator is easily configured to run in parallel, and yields excellent speed-up on SMP hardware.

The utilization of neural nets in populating an object-oriented database

NASA Technical Reports Server (NTRS)

Campbell, William J.; Hill, Scott E.; Cromp, Robert F.

1989-01-01

Existing NASA supported scientific data bases are usually developed, managed and populated in a tedious, error prone and self-limiting way in terms of what can be described in a relational Data Base Management System (DBMS). The next generation Earth remote sensing platforms (i.e., Earth Observation System, (EOS), will be capable of generating data at a rate of over 300 Mbs per second from a suite of instruments designed for different applications. What is needed is an innovative approach that creates object-oriented databases that segment, characterize, catalog and are manageable in a domain-specific context and whose contents are available interactively and in near-real-time to the user community. Described here is work in progress that utilizes an artificial neural net approach to characterize satellite imagery of undefined objects into high-level data objects. The characterized data is then dynamically allocated to an object-oriented data base where it can be reviewed and assessed by a user. The definition, development, and evolution of the overall data system model are steps in the creation of an application-driven knowledge-based scientific information system.

National Laboratory for Advanced Scientific Visualization at UNAM - Mexico

NASA Astrophysics Data System (ADS)

Manea, Marina; Constantin Manea, Vlad; Varela, Alfredo

2016-04-01

In 2015, the National Autonomous University of Mexico (UNAM) joined the family of Universities and Research Centers where advanced visualization and computing plays a key role to promote and advance missions in research, education, community outreach, as well as business-oriented consulting. This initiative provides access to a great variety of advanced hardware and software resources and offers a range of consulting services that spans a variety of areas related to scientific visualization, among which are: neuroanatomy, embryonic development, genome related studies, geosciences, geography, physics and mathematics related disciplines. The National Laboratory for Advanced Scientific Visualization delivers services through three main infrastructure environments: the 3D fully immersive display system Cave, the high resolution parallel visualization system Powerwall, the high resolution spherical displays Earth Simulator. The entire visualization infrastructure is interconnected to a high-performance-computing-cluster (HPCC) called ADA in honor to Ada Lovelace, considered to be the first computer programmer. The Cave is an extra large 3.6m wide room with projected images on the front, left and right, as well as floor walls. Specialized crystal eyes LCD-shutter glasses provide a strong stereo depth perception, and a variety of tracking devices allow software to track the position of a user's hand, head and wand. The Powerwall is designed to bring large amounts of complex data together through parallel computing for team interaction and collaboration. This system is composed by 24 (6x4) high-resolution ultra-thin (2 mm) bezel monitors connected to a high-performance GPU cluster. The Earth Simulator is a large (60") high-resolution spherical display used for global-scale data visualization like geophysical, meteorological, climate and ecology data. The HPCC-ADA, is a 1000+ computing core system, which offers parallel computing resources to applications that requires large quantity of memory as well as large and fast parallel storage systems. The entire system temperature is controlled by an energy and space efficient cooling solution, based on large rear door liquid cooled heat exchangers. This state-of-the-art infrastructure will boost research activities in the region, offer a powerful scientific tool for teaching at undergraduate and graduate levels, and enhance association and cooperation with business-oriented organizations.

pFUnit 3.0 Tutorial Advanced

NASA Technical Reports Server (NTRS)

Clune, Tom

2014-01-01

This tutorial will introduce Fortran developers to unit-testing and test-driven development (TDD) using pFUnit. As with other unit-testing frameworks, pFUnit, simplifies the process of writing, collecting, and executing tests while providing clear diagnostic messages for failing tests. pFUnit specifically targets the development of scientific-technical software written in Fortran and includes customized features such as: assertions for multi-dimensional arrays, distributed (MPI) and thread-based (OpenMP) parallellism, and flexible parameterized tests.These sessions will include numerous examples and hands-on exercises that gradually build in complexity. Attendees are expected to have working knowledge of F90, but familiarity with object-oriented syntax in F2003 and MPI will be of benefit for the more advanced examples. By the end of the tutorial the audience should feel comfortable in applying pFUnit within their own development environment.

Implementation of an Object-Oriented Flight Simulator D.C. Electrical System on a Hypercube Architecture

DTIC Science & Technology

1991-12-01

abstract data type is, what an object-oriented design is and how to apply "software engineering" principles to the design of both of them. I owe a great... Program (ASVP), a research and development effort by two aerospace contractors to redesign and implement subsets of two existing flight simulators in...effort addresses how to implement a simulator designed using the SEI OOD Paradigm on a distributed, parallel, multiple instruction, multiple data (MIMD

Horizontal and vertical integration of academic disciplines in the medical school curriculum.

PubMed

Vidic, Branislav; Weitlauf, Harry M

2002-05-01

A rapid expansion of new scientific information and the introduction of new technology in operative and diagnostic medicine has marked the last several decades. Medical educators, because of and parallel to these developments, initiated a search for a more effective system of presenting core material to medical students. The new educational trends, although varying somewhat from one institution to another, concentrated on the following pedagogical shifts: 1) expansion of conceptual presentation of material at the expense of detail-oriented education; 2) amplification of an integrated approach, as opposed to subject-oriented instruction; 3) scheduling of elective courses to compliment required courses in the curriculum; and 4) institution of small group instruction (i.e., problem-based learning) to actively involve students in the educational process and to develop deductive reasoning based on clinical cases. The future pedagogical system in medical schools will most likely be a combination of "classical" presentation of material combined with concept-oriented, subject-integrated and small group instruction based on either hypothetical or real clinical cases. It is imperative for the success of the new curriculum, however, that certain criteria are satisfied: 1) reorganize basic science departments to determine course ownership; 2) establish a reward system for teaching faculty; and 3) establish new course objectives. Copyright 2002 Wiley-Liss, Inc.

Fortran for the nineties

NASA Technical Reports Server (NTRS)

Himer, J. T.

1992-01-01

Fortran has largely enjoyed prominence for the past few decades as the computer programming language of choice for numerically intensive scientific, engineering, and process control applications. Fortran's well understood static language syntax has allowed resulting parsers and compiler optimizing technologies to often generate among the most efficient and fastest run-time executables, particularly on high-end scalar and vector supercomputers. Computing architectures and paradigms have changed considerably since the last ANSI/ISO Fortran release in 1978, and while FORTRAN 77 has more than survived, it's aged features provide only partial functionality for today's demanding computing environments. The simple block procedural languages have been necessarily evolving, or giving way, to specialized supercomputing, network resource, and object-oriented paradigms. To address these new computing demands, ANSI has worked for the last 12-years with three international public reviews to deliver Fortran 90. Fortran 90 has superseded and replaced ISO FORTRAN 77 internationally as the sole Fortran standard; while in the US, Fortran 90 is expected to be adopted as the ANSI standard this summer, coexisting with ANSI FORTRAN 77 until at least 1996. The development path and current state of Fortran will be briefly described highlighting the many new Fortran 90 syntactic and semantic additions which support (among others): free form source; array syntax; new control structures; modules and interfaces; pointers; derived data types; dynamic memory; enhanced I/O; operator overloading; data abstraction; user optional arguments; new intrinsics for array, bit manipulation, and system inquiry; and enhanced portability through better generic control of underlying system arithmetic models. Examples from dynamical astronomy, signal and image processing will attempt to illustrate Fortran 90's applicability to today's general scalar, vector, and parallel scientific and engineering requirements and object oriented programming paradigms. Time permitting, current work proceeding on the future development of Fortran 2000 and collateral standards will be introduced.

Parallel and Portable Monte Carlo Particle Transport

NASA Astrophysics Data System (ADS)

Lee, S. R.; Cummings, J. C.; Nolen, S. D.; Keen, N. D.

1997-08-01

We have developed a multi-group, Monte Carlo neutron transport code in C++ using object-oriented methods and the Parallel Object-Oriented Methods and Applications (POOMA) class library. This transport code, called MC++, currently computes k and α eigenvalues of the neutron transport equation on a rectilinear computational mesh. It is portable to and runs in parallel on a wide variety of platforms, including MPPs, clustered SMPs, and individual workstations. It contains appropriate classes and abstractions for particle transport and, through the use of POOMA, for portable parallelism. Current capabilities are discussed, along with physics and performance results for several test problems on a variety of hardware, including all three Accelerated Strategic Computing Initiative (ASCI) platforms. Current parallel performance indicates the ability to compute α-eigenvalues in seconds or minutes rather than days or weeks. Current and future work on the implementation of a general transport physics framework (TPF) is also described. This TPF employs modern C++ programming techniques to provide simplified user interfaces, generic STL-style programming, and compile-time performance optimization. Physics capabilities of the TPF will be extended to include continuous energy treatments, implicit Monte Carlo algorithms, and a variety of convergence acceleration techniques such as importance combing.

A Scalable, Open Source Platform for Data Processing, Archiving and Dissemination

DTIC Science & Technology

2016-01-01

Object Oriented Data Technology (OODT) big data toolkit developed by NASA and the Work-flow INstance Generation and Selection (WINGS) scientific work...to several challenge big data problems and demonstrated the utility of OODT-WINGS in addressing them. Specific demonstrated analyses address i...source software, Apache, Object Oriented Data Technology, OODT, semantic work-flows, WINGS, big data , work- flow management 16. SECURITY CLASSIFICATION OF

Creating ensembles of oblique decision trees with evolutionary algorithms and sampling

DOEpatents

Cantu-Paz, Erick [Oakland, CA; Kamath, Chandrika [Tracy, CA

2006-06-13

A decision tree system that is part of a parallel object-oriented pattern recognition system, which in turn is part of an object oriented data mining system. A decision tree process includes the step of reading the data. If necessary, the data is sorted. A potential split of the data is evaluated according to some criterion. An initial split of the data is determined. The final split of the data is determined using evolutionary algorithms and statistical sampling techniques. The data is split. Multiple decision trees are combined in ensembles.

Implementing Access to Data Distributed on Many Processors

NASA Technical Reports Server (NTRS)

James, Mark

2006-01-01

A reference architecture is defined for an object-oriented implementation of domains, arrays, and distributions written in the programming language Chapel. This technology primarily addresses domains that contain arrays that have regular index sets with the low-level implementation details being beyond the scope of this discussion. What is defined is a complete set of object-oriented operators that allows one to perform data distributions for domain arrays involving regular arithmetic index sets. What is unique is that these operators allow for the arbitrary regions of the arrays to be fragmented and distributed across multiple processors with a single point of access giving the programmer the illusion that all the elements are collocated on a single processor. Today's massively parallel High Productivity Computing Systems (HPCS) are characterized by a modular structure, with a large number of processing and memory units connected by a high-speed network. Locality of access as well as load balancing are primary concerns in these systems that are typically used for high-performance scientific computation. Data distributions address these issues by providing a range of methods for spreading large data sets across the components of a system. Over the past two decades, many languages, systems, tools, and libraries have been developed for the support of distributions. Since the performance of data parallel applications is directly influenced by the distribution strategy, users often resort to low-level programming models that allow fine-tuning of the distribution aspects affecting performance, but, at the same time, are tedious and error-prone. This technology presents a reusable design of a data-distribution framework for data parallel high-performance applications. Distributions are a means to express locality in systems composed of large numbers of processor and memory components connected by a network. Since distributions have a great effect on the performance of applications, it is important that the distribution strategy is flexible, so its behavior can change depending on the needs of the application. At the same time, high productivity concerns require that the user be shielded from error-prone, tedious details such as communication and synchronization.

Responses to Orientation Discontinuities in V1 and V2: Physiological Dissociations and Functional Implications

PubMed Central

Purpura, Keith P.; Victor, Jonathan D.

2014-01-01

Segmenting the visual image into objects is a crucial stage of visual processing. Object boundaries are typically associated with differences in luminance, but discontinuities in texture also play an important role. We showed previously that a subpopulation of neurons in V2 in anesthetized macaques responds to orientation discontinuities parallel to their receptive field orientation. Such single-cell responses could be a neurophysiological correlate of texture boundary detection. Neurons in V1, on the other hand, are known to have contextual response modulations such as iso-orientation surround suppression, which also produce responses to orientation discontinuities. Here, we use pseudorandom multiregion grating stimuli of two frame durations (20 and 40 ms) to probe and compare texture boundary responses in V1 and V2 in anesthetized macaque monkeys. In V1, responses to texture boundaries were observed for only the 40 ms frame duration and were independent of the orientation of the texture boundary. However, in transient V2 neurons, responses to such texture boundaries were robust for both frame durations and were stronger for boundaries parallel to the neuron's preferred orientation. The dependence of these processes on stimulus duration and orientation indicates that responses to texture boundaries in V2 arise independently of contextual modulations in V1. In addition, because the responses in transient V2 neurons are sensitive to the orientation of the texture boundary but those of V1 neurons are not, we suggest that V2 responses are the correlate of texture boundary detection, whereas contextual modulation in V1 serves other purposes, possibly related to orientation “pop-out.” PMID:24599456

Possible functions of contextual modulations and receptive field nonlinearities: pop-out and texture segmentation

PubMed Central

Schmid, Anita M.; Victor, Jonathan D.

2014-01-01

When analyzing a visual image, the brain has to achieve several goals quickly. One crucial goal is to rapidly detect parts of the visual scene that might be behaviorally relevant, while another one is to segment the image into objects, to enable an internal representation of the world. Both of these processes can be driven by local variations in any of several image attributes such as luminance, color, and texture. Here, focusing on texture defined by local orientation, we propose that the two processes are mediated by separate mechanisms that function in parallel. More specifically, differences in orientation can cause an object to “pop out” and attract visual attention, if its orientation differs from that of the surrounding objects. Differences in orientation can also signal a boundary between objects and therefore provide useful information for image segmentation. We propose that contextual response modulations in primary visual cortex (V1) are responsible for orientation pop-out, while a different kind of receptive field nonlinearity in secondary visual cortex (V2) is responsible for orientation-based texture segmentation. We review a recent experiment that led us to put forward this hypothesis along with other research literature relevant to this notion. PMID:25064441

A Verification System for Distributed Objects with Asynchronous Method Calls

NASA Astrophysics Data System (ADS)

Ahrendt, Wolfgang; Dylla, Maximilian

We present a verification system for Creol, an object-oriented modeling language for concurrent distributed applications. The system is an instance of KeY, a framework for object-oriented software verification, which has so far been applied foremost to sequential Java. Building on KeY characteristic concepts, like dynamic logic, sequent calculus, explicit substitutions, and the taclet rule language, the system presented in this paper addresses functional correctness of Creol models featuring local cooperative thread parallelism and global communication via asynchronous method calls. The calculus heavily operates on communication histories which describe the interfaces of Creol units. Two example scenarios demonstrate the usage of the system.

Motion streaks in fast motion rivalry cause orientation-selective suppression.

PubMed

Apthorp, Deborah; Wenderoth, Peter; Alais, David

2009-05-14

We studied binocular rivalry between orthogonally translating arrays of random Gaussian blobs and measured the strength of rivalry suppression for static oriented probes. Suppression depth was quantified by expressing monocular probe thresholds during dominance relative to thresholds during suppression. Rivalry between two fast motions or two slow motions was compared in order to test the suggestion that fast-moving objects leave oriented "motion streaks" due to temporal integration (W. S. Geisler, 1999). If fast motions do produce motion streaks, then fast motion rivalry might also entail rivalry between the orthogonal streak orientations. We tested this using a static oriented probe that was aligned either parallel to the motion trajectory (hence collinear with the "streaks") or was orthogonal to the trajectory, predicting that rivalry suppression would be greater for parallel probes, and only for rivalry between fast motions. Results confirmed that suppression depth did depend on probe orientation for fast motion but not for slow motion. Further experiments showed that threshold elevations for the oriented probe during suppression exhibited clear orientation tuning. However, orientation-tuned elevations were also present during dominance, suggesting within-channel masking as the basis of the extra-deep suppression. In sum, the presence of orientation-dependent suppression in fast motion rivalry is consistent with the "motion streaks" hypothesis.

Integrated Task and Data Parallel Programming

NASA Technical Reports Server (NTRS)

Grimshaw, A. S.

1998-01-01

This research investigates the combination of task and data parallel language constructs within a single programming language. There are an number of applications that exhibit properties which would be well served by such an integrated language. Examples include global climate models, aircraft design problems, and multidisciplinary design optimization problems. Our approach incorporates data parallel language constructs into an existing, object oriented, task parallel language. The language will support creation and manipulation of parallel classes and objects of both types (task parallel and data parallel). Ultimately, the language will allow data parallel and task parallel classes to be used either as building blocks or managers of parallel objects of either type, thus allowing the development of single and multi-paradigm parallel applications. 1995 Research Accomplishments In February I presented a paper at Frontiers 1995 describing the design of the data parallel language subset. During the spring I wrote and defended my dissertation proposal. Since that time I have developed a runtime model for the language subset. I have begun implementing the model and hand-coding simple examples which demonstrate the language subset. I have identified an astrophysical fluid flow application which will validate the data parallel language subset. 1996 Research Agenda Milestones for the coming year include implementing a significant portion of the data parallel language subset over the Legion system. Using simple hand-coded methods, I plan to demonstrate (1) concurrent task and data parallel objects and (2) task parallel objects managing both task and data parallel objects. My next steps will focus on constructing a compiler and implementing the fluid flow application with the language. Concurrently, I will conduct a search for a real-world application exhibiting both task and data parallelism within the same program. Additional 1995 Activities During the fall I collaborated with Andrew Grimshaw and Adam Ferrari to write a book chapter which will be included in Parallel Processing in C++ edited by Gregory Wilson. I also finished two courses, Compilers and Advanced Compilers, in 1995. These courses complete my class requirements at the University of Virginia. I have only my dissertation research and defense to complete.

Integrated Task And Data Parallel Programming: Language Design

NASA Technical Reports Server (NTRS)

Grimshaw, Andrew S.; West, Emily A.

1998-01-01

his research investigates the combination of task and data parallel language constructs within a single programming language. There are an number of applications that exhibit properties which would be well served by such an integrated language. Examples include global climate models, aircraft design problems, and multidisciplinary design optimization problems. Our approach incorporates data parallel language constructs into an existing, object oriented, task parallel language. The language will support creation and manipulation of parallel classes and objects of both types (task parallel and data parallel). Ultimately, the language will allow data parallel and task parallel classes to be used either as building blocks or managers of parallel objects of either type, thus allowing the development of single and multi-paradigm parallel applications. 1995 Research Accomplishments In February I presented a paper at Frontiers '95 describing the design of the data parallel language subset. During the spring I wrote and defended my dissertation proposal. Since that time I have developed a runtime model for the language subset. I have begun implementing the model and hand-coding simple examples which demonstrate the language subset. I have identified an astrophysical fluid flow application which will validate the data parallel language subset. 1996 Research Agenda Milestones for the coming year include implementing a significant portion of the data parallel language subset over the Legion system. Using simple hand-coded methods, I plan to demonstrate (1) concurrent task and data parallel objects and (2) task parallel objects managing both task and data parallel objects. My next steps will focus on constructing a compiler and implementing the fluid flow application with the language. Concurrently, I will conduct a search for a real-world application exhibiting both task and data parallelism within the same program m. Additional 1995 Activities During the fall I collaborated with Andrew Grimshaw and Adam Ferrari to write a book chapter which will be included in Parallel Processing in C++ edited by Gregory Wilson. I also finished two courses, Compilers and Advanced Compilers, in 1995. These courses complete my class requirements at the University of Virginia. I have only my dissertation research and defense to complete.

Performance of the Heavy Flavor Tracker (HFT) detector in star experiment at RHIC

NASA Astrophysics Data System (ADS)

Alruwaili, Manal

With the growing technology, the number of the processors is becoming massive. Current supercomputer processing will be available on desktops in the next decade. For mass scale application software development on massive parallel computing available on desktops, existing popular languages with large libraries have to be augmented with new constructs and paradigms that exploit massive parallel computing and distributed memory models while retaining the user-friendliness. Currently, available object oriented languages for massive parallel computing such as Chapel, X10 and UPC++ exploit distributed computing, data parallel computing and thread-parallelism at the process level in the PGAS (Partitioned Global Address Space) memory model. However, they do not incorporate: 1) any extension at for object distribution to exploit PGAS model; 2) the programs lack the flexibility of migrating or cloning an object between places to exploit load balancing; and 3) lack the programming paradigms that will result from the integration of data and thread-level parallelism and object distribution. In the proposed thesis, I compare different languages in PGAS model; propose new constructs that extend C++ with object distribution and object migration; and integrate PGAS based process constructs with these extensions on distributed objects. Object cloning and object migration. Also a new paradigm MIDD (Multiple Invocation Distributed Data) is presented when different copies of the same class can be invoked, and work on different elements of a distributed data concurrently using remote method invocations. I present new constructs, their grammar and their behavior. The new constructs have been explained using simple programs utilizing these constructs.

Parallel object-oriented decision tree system

DOEpatents

Kamath,; Chandrika, Cantu-Paz [Dublin, CA; Erick, [Oakland, CA

2006-02-28

A data mining decision tree system that uncovers patterns, associations, anomalies, and other statistically significant structures in data by reading and displaying data files, extracting relevant features for each of the objects, and using a method of recognizing patterns among the objects based upon object features through a decision tree that reads the data, sorts the data if necessary, determines the best manner to split the data into subsets according to some criterion, and splits the data.

Computational Science in Armenia (Invited Talk)

NASA Astrophysics Data System (ADS)

Marandjian, H.; Shoukourian, Yu.

This survey is devoted to the development of informatics and computer science in Armenia. The results in theoretical computer science (algebraic models, solutions to systems of general form recursive equations, the methods of coding theory, pattern recognition and image processing), constitute the theoretical basis for developing problem-solving-oriented environments. As examples can be mentioned: a synthesizer of optimized distributed recursive programs, software tools for cluster-oriented implementations of two-dimensional cellular automata, a grid-aware web interface with advanced service trading for linear algebra calculations. In the direction of solving scientific problems that require high-performance computing resources, examples of completed projects include the field of physics (parallel computing of complex quantum systems), astrophysics (Armenian virtual laboratory), biology (molecular dynamics study of human red blood cell membrane), meteorology (implementing and evaluating the Weather Research and Forecast Model for the territory of Armenia). The overview also notes that the Institute for Informatics and Automation Problems of the National Academy of Sciences of Armenia has established a scientific and educational infrastructure, uniting computing clusters of scientific and educational institutions of the country and provides the scientific community with access to local and international computational resources, that is a strong support for computational science in Armenia.

Frequent Statement and Dereference Elimination for Imperative and Object-Oriented Distributed Programs

PubMed Central

El-Zawawy, Mohamed A.

2014-01-01

This paper introduces new approaches for the analysis of frequent statement and dereference elimination for imperative and object-oriented distributed programs running on parallel machines equipped with hierarchical memories. The paper uses languages whose address spaces are globally partitioned. Distributed programs allow defining data layout and threads writing to and reading from other thread memories. Three type systems (for imperative distributed programs) are the tools of the proposed techniques. The first type system defines for every program point a set of calculated (ready) statements and memory accesses. The second type system uses an enriched version of types of the first type system and determines which of the ready statements and memory accesses are used later in the program. The third type system uses the information gather so far to eliminate unnecessary statement computations and memory accesses (the analysis of frequent statement and dereference elimination). Extensions to these type systems are also presented to cover object-oriented distributed programs. Two advantages of our work over related work are the following. The hierarchical style of concurrent parallel computers is similar to the memory model used in this paper. In our approach, each analysis result is assigned a type derivation (serves as a correctness proof). PMID:24892098

Angular trapping of anisometric nano-objects in a fluid.

PubMed

Celebrano, Michele; Rosman, Christina; Sönnichsen, Carsten; Krishnan, Madhavi

2012-11-14

We demonstrate the ability to trap, levitate, and orient single anisometric nanoscale objects with high angular precision in a fluid. An electrostatic fluidic trap confines a spherical object at a spatial location defined by the minimum of the electrostatic system free energy. For an anisometric object and a potential well lacking angular symmetry, the system free energy can further strongly depend on the object's orientation in the trap. Engineering the morphology of the trap thus enables precise spatial and angular confinement of a single levitating nano-object, and the process can be massively parallelized. Since the physics of the trap depends strongly on the surface charge of the object, the method is insensitive to the object's dielectric function. Furthermore, levitation of the assembled objects renders them amenable to individual manipulation using externally applied optical, electrical, or hydrodynamic fields, raising prospects for reconfigurable chip-based nano-object assemblies.

Parallel Implementation of the Discontinuous Galerkin Method

NASA Technical Reports Server (NTRS)

Baggag, Abdalkader; Atkins, Harold; Keyes, David

1999-01-01

This paper describes a parallel implementation of the discontinuous Galerkin method. Discontinuous Galerkin is a spatially compact method that retains its accuracy and robustness on non-smooth unstructured grids and is well suited for time dependent simulations. Several parallelization approaches are studied and evaluated. The most natural and symmetric of the approaches has been implemented in all object-oriented code used to simulate aeroacoustic scattering. The parallel implementation is MPI-based and has been tested on various parallel platforms such as the SGI Origin, IBM SP2, and clusters of SGI and Sun workstations. The scalability results presented for the SGI Origin show slightly superlinear speedup on a fixed-size problem due to cache effects.

An object-oriented, coprocessor-accelerated model for ice sheet simulations

NASA Astrophysics Data System (ADS)

Seddik, H.; Greve, R.

2013-12-01

Recently, numerous models capable of modeling the thermo-dynamics of ice sheets have been developed within the ice sheet modeling community. Their capabilities have been characterized by a wide range of features with different numerical methods (finite difference or finite element), different implementations of the ice flow mechanics (shallow-ice, higher-order, full Stokes) and different treatments for the basal and coastal areas (basal hydrology, basal sliding, ice shelves). Shallow-ice models (SICOPOLIS, IcIES, PISM, etc) have been widely used for modeling whole ice sheets (Greenland and Antarctica) due to the relatively low computational cost of the shallow-ice approximation but higher order (ISSM, AIF) and full Stokes (Elmer/Ice) models have been recently used to model the Greenland ice sheet. The advance in processor speed and the decrease in cost for accessing large amount of memory and storage have undoubtedly been the driving force in the commoditization of models with higher capabilities, and the popularity of Elmer/Ice (http://elmerice.elmerfem.com) with an active user base is a notable representation of this trend. Elmer/Ice is a full Stokes model built on top of the multi-physics package Elmer (http://www.csc.fi/english/pages/elmer) which provides the full machinery for the complex finite element procedure and is fully parallel (mesh partitioning with OpenMPI communication). Elmer is mainly written in Fortran 90 and targets essentially traditional processors as the code base was not initially written to run on modern coprocessors (yet adding support for the recently introduced x86 based coprocessors is possible). Furthermore, a truly modular and object-oriented implementation is required for quick adaptation to fast evolving capabilities in hardware (Fortran 2003 provides an object-oriented programming model while not being clean and requiring a tricky refactoring of Elmer code). In this work, the object-oriented, coprocessor-accelerated finite element code Sainou is introduced. Sainou is an Elmer fork which is reimplemented in Objective C and used for experimenting with ice sheet models running on coprocessors, essentially GPU devices. GPUs are highly parallel processors that provide opportunities for fine-grained parallelization of the full Stokes problem using the standard OpenCL language (http://www.khronos.org/opencl/) to access the device. Sainou is built upon a collection of Objective C base classes that service a modular kernel (itself a base class) which provides the core methods to solve the finite element problem. An early implementation of Sainou will be presented with emphasis on the object architecture and the strategies of parallelizations. The computation of a simple heat conduction problem is used to test the implementation which also provides experimental support for running the global matrix assembly on GPU.

An Object-Oriented Network-Centric Software Architecture for Physical Computing

NASA Astrophysics Data System (ADS)

Palmer, Richard

1997-08-01

Recent developments in object-oriented computer languages and infrastructure such as the Internet, Web browsers, and the like provide an opportunity to define a more productive computational environment for scientific programming that is based more closely on the underlying mathematics describing physics than traditional programming languages such as FORTRAN or C++. In this talk I describe an object-oriented software architecture for representing physical problems that includes classes for such common mathematical objects as geometry, boundary conditions, partial differential and integral equations, discretization and numerical solution methods, etc. In practice, a scientific program written using this architecture looks remarkably like the mathematics used to understand the problem, is typically an order of magnitude smaller than traditional FORTRAN or C++ codes, and hence easier to understand, debug, describe, etc. All objects in this architecture are ``network-enabled,'' which means that components of a software solution to a physical problem can be transparently loaded from anywhere on the Internet or other global network. The architecture is expressed as an ``API,'' or application programmers interface specification, with reference embeddings in Java, Python, and C++. A C++ class library for an early version of this API has been implemented for machines ranging from PC's to the IBM SP2, meaning that phidentical codes run on all architectures.

Moose: An Open-Source Framework to Enable Rapid Development of Collaborative, Multi-Scale, Multi-Physics Simulation Tools

NASA Astrophysics Data System (ADS)

Slaughter, A. E.; Permann, C.; Peterson, J. W.; Gaston, D.; Andrs, D.; Miller, J.

2014-12-01

The Idaho National Laboratory (INL)-developed Multiphysics Object Oriented Simulation Environment (MOOSE; www.mooseframework.org), is an open-source, parallel computational framework for enabling the solution of complex, fully implicit multiphysics systems. MOOSE provides a set of computational tools that scientists and engineers can use to create sophisticated multiphysics simulations. Applications built using MOOSE have computed solutions for chemical reaction and transport equations, computational fluid dynamics, solid mechanics, heat conduction, mesoscale materials modeling, geomechanics, and others. To facilitate the coupling of diverse and highly-coupled physical systems, MOOSE employs the Jacobian-free Newton-Krylov (JFNK) method when solving the coupled nonlinear systems of equations arising in multiphysics applications. The MOOSE framework is written in C++, and leverages other high-quality, open-source scientific software packages such as LibMesh, Hypre, and PETSc. MOOSE uses a "hybrid parallel" model which combines both shared memory (thread-based) and distributed memory (MPI-based) parallelism to ensure efficient resource utilization on a wide range of computational hardware. MOOSE-based applications are inherently modular, which allows for simulation expansion (via coupling of additional physics modules) and the creation of multi-scale simulations. Any application developed with MOOSE supports running (in parallel) any other MOOSE-based application. Each application can be developed independently, yet easily communicate with other applications (e.g., conductivity in a slope-scale model could be a constant input, or a complete phase-field micro-structure simulation) without additional code being written. This method of development has proven effective at INL and expedites the development of sophisticated, sustainable, and collaborative simulation tools.

Performance Analysis of an Actor-Based Distributed Simulation

NASA Technical Reports Server (NTRS)

Schoeffler, James D.

1998-01-01

Object-oriented design of simulation programs appears to be very attractive because of the natural association of components in the simulated system with objects. There is great potential in distributing the simulation across several computers for the purpose of parallel computation and its consequent handling of larger problems in less elapsed time. One approach to such a design is to use "actors", that is, active objects with their own thread of control. Because these objects execute concurrently, communication is via messages. This is in contrast to an object-oriented design using passive objects where communication between objects is via method calls (direct calls when they are in the same address space and remote procedure calls when they are in different address spaces or different machines). This paper describes a performance analysis program for the evaluation of a design for distributed simulations based upon actors.

Integrating end-to-end threads of control into object-oriented analysis and design

NASA Technical Reports Server (NTRS)

Mccandlish, Janet E.; Macdonald, James R.; Graves, Sara J.

1993-01-01

Current object-oriented analysis and design methodologies fall short in their use of mechanisms for identifying threads of control for the system being developed. The scenarios which typically describe a system are more global than looking at the individual objects and representing their behavior. Unlike conventional methodologies that use data flow and process-dependency diagrams, object-oriented methodologies do not provide a model for representing these global threads end-to-end. Tracing through threads of control is key to ensuring that a system is complete and timing constraints are addressed. The existence of multiple threads of control in a system necessitates a partitioning of the system into processes. This paper describes the application and representation of end-to-end threads of control to the object-oriented analysis and design process using object-oriented constructs. The issue of representation is viewed as a grouping problem, that is, how to group classes/objects at a higher level of abstraction so that the system may be viewed as a whole with both classes/objects and their associated dynamic behavior. Existing object-oriented development methodology techniques are extended by adding design-level constructs termed logical composite classes and process composite classes. Logical composite classes are design-level classes which group classes/objects both logically and by thread of control information. Process composite classes further refine the logical composite class groupings by using process partitioning criteria to produce optimum concurrent execution results. The goal of these design-level constructs is to ultimately provide the basis for a mechanism that can support the creation of process composite classes in an automated way. Using an automated mechanism makes it easier to partition a system into concurrently executing elements that can be run in parallel on multiple processors.

Automatic labeling and characterization of objects using artificial neural networks

NASA Technical Reports Server (NTRS)

Campbell, William J.; Hill, Scott E.; Cromp, Robert F.

1989-01-01

Existing NASA supported scientific data bases are usually developed, managed and populated in a tedious, error prone and self-limiting way in terms of what can be described in a relational Data Base Management System (DBMS). The next generation Earth remote sensing platforms, i.e., Earth Observation System, (EOS), will be capable of generating data at a rate of over 300 Mbs per second from a suite of instruments designed for different applications. What is needed is an innovative approach that creates object-oriented databases that segment, characterize, catalog and are manageable in a domain-specific context and whose contents are available interactively and in near-real-time to the user community. Described here is work in progress that utilizes an artificial neural net approach to characterize satellite imagery of undefined objects into high-level data objects. The characterized data is then dynamically allocated to an object-oriented data base where it can be reviewed and assessed by a user. The definition, development, and evolution of the overall data system model are steps in the creation of an application-driven knowledge-based scientific information system.

Applying AN Object-Oriented Database Model to a Scientific Database Problem: Managing Experimental Data at Cebaf.

NASA Astrophysics Data System (ADS)

Ehlmann, Bryon K.

Current scientific experiments are often characterized by massive amounts of very complex data and the need for complex data analysis software. Object-oriented database (OODB) systems have the potential of improving the description of the structure and semantics of this data and of integrating the analysis software with the data. This dissertation results from research to enhance OODB functionality and methodology to support scientific databases (SDBs) and, more specifically, to support a nuclear physics experiments database for the Continuous Electron Beam Accelerator Facility (CEBAF). This research to date has identified a number of problems related to the practical application of OODB technology to the conceptual design of the CEBAF experiments database and other SDBs: the lack of a generally accepted OODB design methodology, the lack of a standard OODB model, the lack of a clear conceptual level in existing OODB models, and the limited support in existing OODB systems for many common object relationships inherent in SDBs. To address these problems, the dissertation describes an Object-Relationship Diagram (ORD) and an Object-oriented Database Definition Language (ODDL) that provide tools that allow SDB design and development to proceed systematically and independently of existing OODB systems. These tools define multi-level, conceptual data models for SDB design, which incorporate a simple notation for describing common types of relationships that occur in SDBs. ODDL allows these relationships and other desirable SDB capabilities to be supported by an extended OODB system. A conceptual model of the CEBAF experiments database is presented in terms of ORDs and the ODDL to demonstrate their functionality and use and provide a foundation for future development of experimental nuclear physics software using an OODB approach.

Open-Source Development of the Petascale Reactive Flow and Transport Code PFLOTRAN

NASA Astrophysics Data System (ADS)

Hammond, G. E.; Andre, B.; Bisht, G.; Johnson, T.; Karra, S.; Lichtner, P. C.; Mills, R. T.

2013-12-01

Open-source software development has become increasingly popular in recent years. Open-source encourages collaborative and transparent software development and promotes unlimited free redistribution of source code to the public. Open-source development is good for science as it reveals implementation details that are critical to scientific reproducibility, but generally excluded from journal publications. In addition, research funds that would have been spent on licensing fees can be redirected to code development that benefits more scientists. In 2006, the developers of PFLOTRAN open-sourced their code under the U.S. Department of Energy SciDAC-II program. Since that time, the code has gained popularity among code developers and users from around the world seeking to employ PFLOTRAN to simulate thermal, hydraulic, mechanical and biogeochemical processes in the Earth's surface/subsurface environment. PFLOTRAN is a massively-parallel subsurface reactive multiphase flow and transport simulator designed from the ground up to run efficiently on computing platforms ranging from the laptop to leadership-class supercomputers, all from a single code base. The code employs domain decomposition for parallelism and is founded upon the well-established and open-source parallel PETSc and HDF5 frameworks. PFLOTRAN leverages modern Fortran (i.e. Fortran 2003-2008) in its extensible object-oriented design. The use of this progressive, yet domain-friendly programming language has greatly facilitated collaboration in the code's software development. Over the past year, PFLOTRAN's top-level data structures were refactored as Fortran classes (i.e. extendible derived types) to improve the flexibility of the code, ease the addition of new process models, and enable coupling to external simulators. For instance, PFLOTRAN has been coupled to the parallel electrical resistivity tomography code E4D to enable hydrogeophysical inversion while the same code base can be used as a third-party library to provide hydrologic flow, energy transport, and biogeochemical capability to the community land model, CLM, part of the open-source community earth system model (CESM) for climate. In this presentation, the advantages and disadvantages of open source software development in support of geoscience research at government laboratories, universities, and the private sector are discussed. Since the code is open-source (i.e. it's transparent and readily available to competitors), the PFLOTRAN team's development strategy within a competitive research environment is presented. Finally, the developers discuss their approach to object-oriented programming and the leveraging of modern Fortran in support of collaborative geoscience research as the Fortran standard evolves among compiler vendors.

Performance of OVERFLOW-D Applications based on Hybrid and MPI Paradigms on IBM Power4 System

NASA Technical Reports Server (NTRS)

Djomehri, M. Jahed; Biegel, Bryan (Technical Monitor)

2002-01-01

This report briefly discusses our preliminary performance experiments with parallel versions of OVERFLOW-D applications. These applications are based on MPI and hybrid paradigms on the IBM Power4 system here at the NAS Division. This work is part of an effort to determine the suitability of the system and its parallel libraries (MPI/OpenMP) for specific scientific computing objectives.

Directions in parallel programming: HPF, shared virtual memory and object parallelism in pC++

NASA Technical Reports Server (NTRS)

Bodin, Francois; Priol, Thierry; Mehrotra, Piyush; Gannon, Dennis

1994-01-01

Fortran and C++ are the dominant programming languages used in scientific computation. Consequently, extensions to these languages are the most popular for programming massively parallel computers. We discuss two such approaches to parallel Fortran and one approach to C++. The High Performance Fortran Forum has designed HPF with the intent of supporting data parallelism on Fortran 90 applications. HPF works by asking the user to help the compiler distribute and align the data structures with the distributed memory modules in the system. Fortran-S takes a different approach in which the data distribution is managed by the operating system and the user provides annotations to indicate parallel control regions. In the case of C++, we look at pC++ which is based on a concurrent aggregate parallel model.

Scientific communication in clinical psychology: examining patterns of citations and references.

PubMed

Kiselica, Andrew M; Ruscio, John

2014-01-01

Previous studies of scientific communication used citation mapping, establishing psychology as a 'hub science' from which many other fields draw information. Within psychology, the clinical and counselling discipline is a major 'knowledge broker'. This study analyzed scientific communication among three major subdisciplines of clinical psychology-the cognitive-behavioural, psychodynamic and humanistic schools of thought-by examining patterns of references within and citations to 305 target articles published in leading journals of these subdisciplines. The results suggest that clinical researchers of each theoretical orientation engage in more insular scientific communication than an integrationist would find desirable and that cognitive-behavioural articles are more closely connected to mainstream psychology and related fields. Eclectic practitioners draw on several different theoretical orientations to inform their practice; as such, they should be interested in understanding the patterns of scientific communication within and across theoretical orientations. Practitioners work in a variety of different mental health settings, with a variety of other professionals in psychology-related fields, and should be interested in how much influence their particular theoretical orientation has on the work of colleagues. Many practitioners rely on new, evidence-based research to inform their work. The results of this study provide these individuals with an objective measure of the influence of empirical work in different areas of clinical psychology. Copyright © 2012 John Wiley & Sons, Ltd.

The Dynamo package for tomography and subtomogram averaging: components for MATLAB, GPU computing and EC2 Amazon Web Services

PubMed Central

Castaño-Díez, Daniel

2017-01-01

Dynamo is a package for the processing of tomographic data. As a tool for subtomogram averaging, it includes different alignment and classification strategies. Furthermore, its data-management module allows experiments to be organized in groups of tomograms, while offering specialized three-dimensional tomographic browsers that facilitate visualization, location of regions of interest, modelling and particle extraction in complex geometries. Here, a technical description of the package is presented, focusing on its diverse strategies for optimizing computing performance. Dynamo is built upon mbtools (middle layer toolbox), a general-purpose MATLAB library for object-oriented scientific programming specifically developed to underpin Dynamo but usable as an independent tool. Its structure intertwines a flexible MATLAB codebase with precompiled C++ functions that carry the burden of numerically intensive operations. The package can be delivered as a precompiled standalone ready for execution without a MATLAB license. Multicore parallelization on a single node is directly inherited from the high-level parallelization engine provided for MATLAB, automatically imparting a balanced workload among the threads in computationally intense tasks such as alignment and classification, but also in logistic-oriented tasks such as tomogram binning and particle extraction. Dynamo supports the use of graphical processing units (GPUs), yielding considerable speedup factors both for native Dynamo procedures (such as the numerically intensive subtomogram alignment) and procedures defined by the user through its MATLAB-based GPU library for three-dimensional operations. Cloud-based virtual computing environments supplied with a pre-installed version of Dynamo can be publicly accessed through the Amazon Elastic Compute Cloud (EC2), enabling users to rent GPU computing time on a pay-as-you-go basis, thus avoiding upfront investments in hardware and longterm software maintenance. PMID:28580909

The Dynamo package for tomography and subtomogram averaging: components for MATLAB, GPU computing and EC2 Amazon Web Services.

PubMed

Castaño-Díez, Daniel

2017-06-01

Dynamo is a package for the processing of tomographic data. As a tool for subtomogram averaging, it includes different alignment and classification strategies. Furthermore, its data-management module allows experiments to be organized in groups of tomograms, while offering specialized three-dimensional tomographic browsers that facilitate visualization, location of regions of interest, modelling and particle extraction in complex geometries. Here, a technical description of the package is presented, focusing on its diverse strategies for optimizing computing performance. Dynamo is built upon mbtools (middle layer toolbox), a general-purpose MATLAB library for object-oriented scientific programming specifically developed to underpin Dynamo but usable as an independent tool. Its structure intertwines a flexible MATLAB codebase with precompiled C++ functions that carry the burden of numerically intensive operations. The package can be delivered as a precompiled standalone ready for execution without a MATLAB license. Multicore parallelization on a single node is directly inherited from the high-level parallelization engine provided for MATLAB, automatically imparting a balanced workload among the threads in computationally intense tasks such as alignment and classification, but also in logistic-oriented tasks such as tomogram binning and particle extraction. Dynamo supports the use of graphical processing units (GPUs), yielding considerable speedup factors both for native Dynamo procedures (such as the numerically intensive subtomogram alignment) and procedures defined by the user through its MATLAB-based GPU library for three-dimensional operations. Cloud-based virtual computing environments supplied with a pre-installed version of Dynamo can be publicly accessed through the Amazon Elastic Compute Cloud (EC2), enabling users to rent GPU computing time on a pay-as-you-go basis, thus avoiding upfront investments in hardware and longterm software maintenance.

A software bus for thread objects

NASA Technical Reports Server (NTRS)

Callahan, John R.; Li, Dehuai

1995-01-01

The authors have implemented a software bus for lightweight threads in an object-oriented programming environment that allows for rapid reconfiguration and reuse of thread objects in discrete-event simulation experiments. While previous research in object-oriented, parallel programming environments has focused on direct communication between threads, our lightweight software bus, called the MiniBus, provides a means to isolate threads from their contexts of execution by restricting communications between threads to message-passing via their local ports only. The software bus maintains a topology of connections between these ports. It routes, queues, and delivers messages according to this topology. This approach allows for rapid reconfiguration and reuse of thread objects in other systems without making changes to the specifications or source code. A layered approach that provides the needed transparency to developers is presented. Examples of using the MiniBus are given, and the value of bus architectures in building and conducting simulations of discrete-event systems is discussed.

Single-chip microcomputer application in high-altitude balloon orientation system

NASA Technical Reports Server (NTRS)

Lim, T. S.; Ehrmann, C. H.; Allison, S. R.

1980-01-01

This paper describes the application of a single-chip microcomputer in a high-altitude balloon instrumentation system. The system, consisting of a magnetometer, a stepping motor, a microcomputer and a gray code shaft encoder, is used to provide an orientation reference to point a scientific instrument at an object in space. The single-chip microcomputer, Intel's 8748, consisting of a CPU, program memory, data memory and I/O ports, is used to control the orientation of the system.

Data structures and organisation: Special problems in scientific applications

NASA Astrophysics Data System (ADS)

Read, Brian J.

1989-12-01

In this paper we discuss and offer answers to the following questions: What, really, are the benifits of databases in physics? Are scientific databases essentially different from conventional ones? What are the drawbacks of a commercial database management system for use with scientific data? Do they outweigh the advantages? Do databases systems have adequate graphics facilities, or is a separate graphics package necessary? SQL as a standard language has deficiencies, but what are they for scientific data in particular? Indeed, is the relational model appropriate anyway? Or, should we turn to object oriented databases?

Performance analysis of parallel branch and bound search with the hypercube architecture

NASA Technical Reports Server (NTRS)

Mraz, Richard T.

1987-01-01

With the availability of commercial parallel computers, researchers are examining new classes of problems which might benefit from parallel computing. This paper presents results of an investigation of the class of search intensive problems. The specific problem discussed is the Least-Cost Branch and Bound search method of deadline job scheduling. The object-oriented design methodology was used to map the problem into a parallel solution. While the initial design was good for a prototype, the best performance resulted from fine-tuning the algorithm for a specific computer. The experiments analyze the computation time, the speed up over a VAX 11/785, and the load balance of the problem when using loosely coupled multiprocessor system based on the hypercube architecture.

Paradigms and strategies for scientific computing on distributed memory concurrent computers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foster, I.T.; Walker, D.W.

1994-06-01

In this work we examine recent advances in parallel languages and abstractions that have the potential for improving the programmability and maintainability of large-scale, parallel, scientific applications running on high performance architectures and networks. This paper focuses on Fortran M, a set of extensions to Fortran 77 that supports the modular design of message-passing programs. We describe the Fortran M implementation of a particle-in-cell (PIC) plasma simulation application, and discuss issues in the optimization of the code. The use of two other methodologies for parallelizing the PIC application are considered. The first is based on the shared object abstraction asmore » embodied in the Orca language. The second approach is the Split-C language. In Fortran M, Orca, and Split-C the ability of the programmer to control the granularity of communication is important is designing an efficient implementation.« less

Orbital Debris Characterization via Laboratory Optical Measurements

NASA Technical Reports Server (NTRS)

Cowardin, Healther

2011-01-01

Optical observations of orbital debris offer insights that differ from radar measurements (specifically the size parameter,wavelength regime,and altitude range). For example, time-dependent photometric data yield lightcurves in multiple bandpasses that aid in material identification and possible periodic orientations. These data can also be used to help identify shapes and optical properties at multiple phase angles. Capitalizing on optical data products and applying them to generate a more complete understanding of orbital objects is a key objective of NASA's Optical Measurement Program, and the primary reason for the creation of the Optical Measurements Center(OMC). The OMC attempts to emulate space-based illumination conditions using equipment and techniques that parallel telescopic observations and source-target-sensor orientations.

Transformation of shock-compressed graphite to hexagonal diamond in nanoseconds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turneaure, Stefan J.; Sharma, Surinder M.; Volz, Travis J.

2017-10-01

The graphite-to-diamond transformation under shock compression has been of broad scientific interest since 1961. The formation of hexagonal diamond (HD) is of particular interest because it is expected to be harder than cubic diamond and due to its use in terrestrial sciences as a marker at meteorite impact sites. However, the formation of diamond having a fully hexagonal structure continues to be questioned and remains unresolved. Using real-time (nanosecond), in situ x-ray diffraction measurements, we show unequivocally that highly oriented pyrolytic graphite, shock-compressed along the c axis to 50 GPa, transforms to highly oriented elastically strained HD with the (100)HDmore » plane parallel to the graphite basal plane.« less

Temporal resolution of orientation-defined texture segregation: a VEP study.

PubMed

Lachapelle, Julie; McKerral, Michelle; Jauffret, Colin; Bach, Michael

2008-09-01

Orientation is one of the visual dimensions that subserve figure-ground discrimination. A spatial gradient in orientation leads to "texture segregation", which is thought to be concurrent parallel processing across the visual field, without scanning. In the visual-evoked potential (VEP) a component can be isolated which is related to texture segregation ("tsVEP"). Our objective was to evaluate the temporal frequency dependence of the tsVEP to compare processing speed of low-level features (e.g., orientation, using the VEP, here denoted llVEP) with texture segregation because of a recent literature controversy in that regard. Visual-evoked potentials (VEPs) were recorded in seven normal adults. Oriented line segments of 0.1 degrees x 0.8 degrees at 100% contrast were presented in four different arrangements: either oriented in parallel for two homogeneous stimuli (from which were obtained the low-level VEP (llVEP)) or with a 90 degrees orientation gradient for two textured ones (from which were obtained the texture VEP). The orientation texture condition was presented at eight different temporal frequencies ranging from 7.5 to 45 Hz. Fourier analysis was used to isolate low-level components at the pattern-change frequency and texture-segregation components at half that frequency. For all subjects, there was lower high-cutoff frequency for tsVEP than for llVEPs, on average 12 Hz vs. 17 Hz (P = 0.017). The results suggest that the processing of feature gradients to extract texture segregation requires additional processing time, resulting in a lower fusion frequency.

On Parallel Software Engineering Education Using Python

ERIC Educational Resources Information Center

Marowka, Ami

2018-01-01

Python is gaining popularity in academia as the preferred language to teach novices serial programming. The syntax of Python is clean, easy, and simple to understand. At the same time, it is a high-level programming language that supports multi programming paradigms such as imperative, functional, and object-oriented. Therefore, by default, it is…

Retrieving Enduring Spatial Representations after Disorientation

PubMed Central

Li, Xiaoou; Mou, Weimin; McNamara, Timothy P.

2012-01-01

Four experiments tested whether there are enduring spatial representations of objects’ locations in memory. Previous studies have shown that under certain conditions the internal consistency of pointing to objects using memory is disrupted by disorientation. This disorientation effect has been attributed to an absence of or to imprecise enduring spatial representations of objects’ locations. Experiment 1 replicated the standard disorientation effect. Participants learned locations of objects in an irregular layout and then pointed to objects after physically turning to face an object and after disorientation. The expected disorientation was observed. In Experiment 2, after disorientation, participants were asked to imagine they were facing the original learning direction and then physically turned to adopt the test orientation. In Experiment 3, after disorientation, participants turned to adopt the test orientation and then were informed of the original viewing direction by the experimenter. A disorientation effect was not observed in Experiment 2 or 3. In Experiment 4, after disorientation, participants turned to face the test orientation but were not told the original learning orientation. As in Experiment 1, a disorientation effect was observed. These results suggest that there are enduring spatial representations of objects’ locations specified in terms of a spatial reference direction parallel to the learning view, and that the disorientation effect is caused by uncertainty in recovering the spatial reference direction relative to the testing orientation following disorientation. PMID:22682765

Tiger LDRD final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steich, D J; Brugger, S T; Kallman, J S

2000-02-01

This final report describes our efforts on the Three-Dimensional Massively Parallel CEM Technologies LDRD project (97-ERD-009). Significant need exists for more advanced time domain computational electromagnetics modeling. Bookkeeping details and modifying inflexible software constitute a vast majority of the effort required to address such needs. The required effort escalates rapidly as problem complexity increases. For example, hybrid meshes requiring hybrid numerics on massively parallel platforms (MPPs). This project attempts to alleviate the above limitations by investigating flexible abstractions for these numerical algorithms on MPPs using object-oriented methods, providing a programming environment insulating physics from bookkeeping. The three major design iterationsmore » during the project, known as TIGER-I to TIGER-III, are discussed. Each version of TIGER is briefly discussed along with lessons learned during the development and implementation. An Application Programming Interface (API) of the object-oriented interface for Tiger-III is included in three appendices. The three appendices contain the Utilities, Entity-Attribute, and Mesh libraries developed during the project. The API libraries represent a snapshot of our latest attempt at insulated the physics from the bookkeeping.« less

WaveJava: Wavelet-based network computing

NASA Astrophysics Data System (ADS)

Ma, Kun; Jiao, Licheng; Shi, Zhuoer

1997-04-01

Wavelet is a powerful theory, but its successful application still needs suitable programming tools. Java is a simple, object-oriented, distributed, interpreted, robust, secure, architecture-neutral, portable, high-performance, multi- threaded, dynamic language. This paper addresses the design and development of a cross-platform software environment for experimenting and applying wavelet theory. WaveJava, a wavelet class library designed by the object-orient programming, is developed to take advantage of the wavelets features, such as multi-resolution analysis and parallel processing in the networking computing. A new application architecture is designed for the net-wide distributed client-server environment. The data are transmitted with multi-resolution packets. At the distributed sites around the net, these data packets are done the matching or recognition processing in parallel. The results are fed back to determine the next operation. So, the more robust results can be arrived quickly. The WaveJava is easy to use and expand for special application. This paper gives a solution for the distributed fingerprint information processing system. It also fits for some other net-base multimedia information processing, such as network library, remote teaching and filmless picture archiving and communications.

MOOSE: A parallel computational framework for coupled systems of nonlinear equations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derek Gaston; Chris Newman; Glen Hansen

Systems of coupled, nonlinear partial differential equations (PDEs) often arise in simulation of nuclear processes. MOOSE: Multiphysics Object Oriented Simulation Environment, a parallel computational framework targeted at the solution of such systems, is presented. As opposed to traditional data-flow oriented computational frameworks, MOOSE is instead founded on the mathematical principle of Jacobian-free Newton-Krylov (JFNK) solution methods. Utilizing the mathematical structure present in JFNK, physics expressions are modularized into `Kernels,'' allowing for rapid production of new simulation tools. In addition, systems are solved implicitly and fully coupled, employing physics based preconditioning, which provides great flexibility even with large variance in timemore » scales. A summary of the mathematics, an overview of the structure of MOOSE, and several representative solutions from applications built on the framework are presented.« less

Parallelization of Rocket Engine Simulator Software (PRESS)

NASA Technical Reports Server (NTRS)

Cezzar, Ruknet

1997-01-01

Parallelization of Rocket Engine System Software (PRESS) project is part of a collaborative effort with Southern University at Baton Rouge (SUBR), University of West Florida (UWF), and Jackson State University (JSU). The second-year funding, which supports two graduate students enrolled in our new Master's program in Computer Science at Hampton University and the principal investigator, have been obtained for the period from October 19, 1996 through October 18, 1997. The key part of the interim report was new directions for the second year funding. This came about from discussions during Rocket Engine Numeric Simulator (RENS) project meeting in Pensacola on January 17-18, 1997. At that time, a software agreement between Hampton University and NASA Lewis Research Center had already been concluded. That agreement concerns off-NASA-site experimentation with PUMPDES/TURBDES software. Before this agreement, during the first year of the project, another large-scale FORTRAN-based software, Two-Dimensional Kinetics (TDK), was being used for translation to an object-oriented language and parallelization experiments. However, that package proved to be too complex and lacking sufficient documentation for effective translation effort to the object-oriented C + + source code. The focus, this time with better documented and more manageable PUMPDES/TURBDES package, was still on translation to C + + with design improvements. At the RENS Meeting, however, the new impetus for the RENS projects in general, and PRESS in particular, has shifted in two important ways. One was closer alignment with the work on Numerical Propulsion System Simulator (NPSS) through cooperation and collaboration with LERC ACLU organization. The other was to see whether and how NASA's various rocket design software can be run over local and intra nets without any radical efforts for redesign and translation into object-oriented source code. There were also suggestions that the Fortran based code be encapsulated in C + + code thereby facilitating reuse without undue development effort. The details are covered in the aforementioned section of the interim report filed on April 28, 1997.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bailey, David H.

The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, althoughmore » the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the need for a more rational procedure to select new supercomputers for acquisition by NASA. The emergence of commercially available highly parallel computer systems in the late 1980s offered an attractive alternative to parallel vector supercomputers that had been the mainstay of high-end scientific computing. However, the introduction of highly parallel systems was accompanied by a regrettable level of hype, not only on the part of the commercial vendors but even, in some cases, by scientists using the systems. As a result, it was difficult to discern whether the new systems offered any fundamental performance advantage over vector supercomputers, and, if so, which of the parallel offerings would be most useful in real-world scientific computation. In part to draw attention to some of the performance reporting abuses prevalent at the time, the present author wrote a humorous essay 'Twelve Ways to Fool the Masses,' which described in a light-hearted way a number of the questionable ways in which both vendor marketing people and scientists were inflating and distorting their performance results. All of this underscored the need for an objective and scientifically defensible measure to compare performance on these systems.« less

Design Considerations of a Virtual Laboratory for Advanced X-ray Sources

NASA Astrophysics Data System (ADS)

Luginsland, J. W.; Frese, M. H.; Frese, S. D.; Watrous, J. J.; Heileman, G. L.

2004-11-01

The field of scientific computation has greatly advanced in the last few years, resulting in the ability to perform complex computer simulations that can predict the performance of real-world experiments in a number of fields of study. Among the forces driving this new computational capability is the advent of parallel algorithms, allowing calculations in three-dimensional space with realistic time scales. Electromagnetic radiation sources driven by high-voltage, high-current electron beams offer an area to further push the state-of-the-art in high fidelity, first-principles simulation tools. The physics of these x-ray sources combine kinetic plasma physics (electron beams) with dense fluid-like plasma physics (anode plasmas) and x-ray generation (bremsstrahlung). There are a number of mature techniques and software packages for dealing with the individual aspects of these sources, such as Particle-In-Cell (PIC), Magneto-Hydrodynamics (MHD), and radiation transport codes. The current effort is focused on developing an object-oriented software environment using the Rational© Unified Process and the Unified Modeling Language (UML) to provide a framework where multiple 3D parallel physics packages, such as a PIC code (ICEPIC), a MHD code (MACH), and a x-ray transport code (ITS) can co-exist in a system-of-systems approach to modeling advanced x-ray sources. Initial software design and assessments of the various physics algorithms' fidelity will be presented.

An Object Oriented Extensible Architecture for Affordable Aerospace Propulsion Systems

NASA Technical Reports Server (NTRS)

Follen, Gregory J.; Lytle, John K. (Technical Monitor)

2002-01-01

Driven by a need to explore and develop propulsion systems that exceeded current computing capabilities, NASA Glenn embarked on a novel strategy leading to the development of an architecture that enables propulsion simulations never thought possible before. Full engine 3 Dimensional Computational Fluid Dynamic propulsion system simulations were deemed impossible due to the impracticality of the hardware and software computing systems required. However, with a software paradigm shift and an embracing of parallel and distributed processing, an architecture was designed to meet the needs of future propulsion system modeling. The author suggests that the architecture designed at the NASA Glenn Research Center for propulsion system modeling has potential for impacting the direction of development of affordable weapons systems currently under consideration by the Applied Vehicle Technology Panel (AVT). This paper discusses the salient features of the NPSS Architecture including its interface layer, object layer, implementation for accessing legacy codes, numerical zooming infrastructure and its computing layer. The computing layer focuses on the use and deployment of these propulsion simulations on parallel and distributed computing platforms which has been the focus of NASA Ames. Additional features of the object oriented architecture that support MultiDisciplinary (MD) Coupling, computer aided design (CAD) access and MD coupling objects will be discussed. Included will be a discussion of the successes, challenges and benefits of implementing this architecture.

Optimization of beam orientation in radiotherapy using planar geometry

NASA Astrophysics Data System (ADS)

Haas, O. C. L.; Burnham, K. J.; Mills, J. A.

1998-08-01

This paper proposes a new geometrical formulation of the coplanar beam orientation problem combined with a hybrid multiobjective genetic algorithm. The approach is demonstrated by optimizing the beam orientation in two dimensions, with the objectives being formulated using planar geometry. The traditional formulation of the objectives associated with the organs at risk has been modified to account for the use of complex dose delivery techniques such as beam intensity modulation. The new algorithm attempts to replicate the approach of a treatment planner whilst reducing the amount of computation required. Hybrid genetic search operators have been developed to improve the performance of the genetic algorithm by exploiting problem-specific features. The multiobjective genetic algorithm is formulated around the concept of Pareto optimality which enables the algorithm to search in parallel for different objectives. When the approach is applied without constraining the number of beams, the solution produces an indication of the minimum number of beams required. It is also possible to obtain non-dominated solutions for various numbers of beams, thereby giving the clinicians a choice in terms of the number of beams as well as in the orientation of these beams.

Evidence for parallel consolidation of motion direction and orientation into visual short-term memory.

PubMed

Rideaux, Reuben; Apthorp, Deborah; Edwards, Mark

2015-02-12

Recent findings have indicated the capacity to consolidate multiple items into visual short-term memory in parallel varies as a function of the type of information. That is, while color can be consolidated in parallel, evidence suggests that orientation cannot. Here we investigated the capacity to consolidate multiple motion directions in parallel and reexamined this capacity using orientation. This was achieved by determining the shortest exposure duration necessary to consolidate a single item, then examining whether two items, presented simultaneously, could be consolidated in that time. The results show that parallel consolidation of direction and orientation information is possible, and that parallel consolidation of direction appears to be limited to two. Additionally, we demonstrate the importance of adequate separation between feature intervals used to define items when attempting to consolidate in parallel, suggesting that when multiple items are consolidated in parallel, as opposed to serially, the resolution of representations suffer. Finally, we used facilitation of spatial attention to show that the deterioration of item resolution occurs during parallel consolidation, as opposed to storage. © 2015 ARVO.

Early Visual Cortex Dynamics during Top-Down Modulated Shifts of Feature-Selective Attention.

PubMed

Müller, Matthias M; Trautmann, Mireille; Keitel, Christian

2016-04-01

Shifting attention from one color to another color or from color to another feature dimension such as shape or orientation is imperative when searching for a certain object in a cluttered scene. Most attention models that emphasize feature-based selection implicitly assume that all shifts in feature-selective attention underlie identical temporal dynamics. Here, we recorded time courses of behavioral data and steady-state visual evoked potentials (SSVEPs), an objective electrophysiological measure of neural dynamics in early visual cortex to investigate temporal dynamics when participants shifted attention from color or orientation toward color or orientation, respectively. SSVEPs were elicited by four random dot kinematograms that flickered at different frequencies. Each random dot kinematogram was composed of dashes that uniquely combined two features from the dimensions color (red or blue) and orientation (slash or backslash). Participants were cued to attend to one feature (such as color or orientation) and respond to coherent motion targets of the to-be-attended feature. We found that shifts toward color occurred earlier after the shifting cue compared with shifts toward orientation, regardless of the original feature (i.e., color or orientation). This was paralleled in SSVEP amplitude modulations as well as in the time course of behavioral data. Overall, our results suggest different neural dynamics during shifts of attention from color and orientation and the respective shifting destinations, namely, either toward color or toward orientation.

West Virginia US Department of Energy experimental program to stimulate competitive research. Section 2: Human resource development; Section 3: Carbon-based structural materials research cluster; Section 3: Data parallel algorithms for scientific computing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-02-02

This report consists of three separate but related reports. They are (1) Human Resource Development, (2) Carbon-based Structural Materials Research Cluster, and (3) Data Parallel Algorithms for Scientific Computing. To meet the objectives of the Human Resource Development plan, the plan includes K--12 enrichment activities, undergraduate research opportunities for students at the state`s two Historically Black Colleges and Universities, graduate research through cluster assistantships and through a traineeship program targeted specifically to minorities, women and the disabled, and faculty development through participation in research clusters. One research cluster is the chemistry and physics of carbon-based materials. The objective of thismore » cluster is to develop a self-sustaining group of researchers in carbon-based materials research within the institutions of higher education in the state of West Virginia. The projects will involve analysis of cokes, graphites and other carbons in order to understand the properties that provide desirable structural characteristics including resistance to oxidation, levels of anisotropy and structural characteristics of the carbons themselves. In the proposed cluster on parallel algorithms, research by four WVU faculty and three state liberal arts college faculty are: (1) modeling of self-organized critical systems by cellular automata; (2) multiprefix algorithms and fat-free embeddings; (3) offline and online partitioning of data computation; and (4) manipulating and rendering three dimensional objects. This cluster furthers the state Experimental Program to Stimulate Competitive Research plan by building on existing strengths at WVU in parallel algorithms.« less

Personal experiences and emotionality in health-related knowledge exchange in Internet forums: a randomized controlled field experiment comparing responses to facts vs personal experiences.

PubMed

Kimmerle, Joachim; Bientzle, Martina; Cress, Ulrike

2014-12-04

On the Internet, people share personal experiences as well as facts and objective information. This also holds true for the exchange of health-related information in a variety of Internet forums. In online discussions about health topics, both fact-oriented and strongly personal contributions occur on a regular basis. In this field experiment, we examined in what way the particular type of contribution (ie, factual information vs personal experiences) has an impact on the subsequent communication in health-related Internet forums. For this purpose, we posted parallelized queries to 28 comparable Internet forums; queries were identical with regard to the information contained but included either fact-oriented descriptions or personal experiences related to measles vaccination. In the factual information condition, we posted queries to the forums that contained the neutral summary of a scientific article. In the personal experiences condition, we posted queries to the forums that contained the same information as in the first condition, but were framed as personal experiences We found no evidence that personal experiences evoked more responses (mean 3.79, SD 3.91) from other members of the Internet forums than fact-oriented contributions (mean 2.14, SD 2.93, t26=0.126, P=.219). But personal experiences elicited emotional replies (mean 3.17, SD 1.29) from other users to a greater extent than fact-oriented contributions (mean 2.13, SD 1.29, t81=3.659, P<.001). We suggest that personal experiences elicited more emotional replies due to the process of emotional anchoring of people's own style of communication. We recommend future studies should aim at testing the hypotheses with more general and with less emotionally charged topics, constructing different fact-oriented posts, and examining additional potential factors of influence such as personality factors or particular communication situations.

MODELS-3/CMAQ APPLICATIONS WHICH ILLUSTRATE CAPABILITY AND FUNCTIONALITY

EPA Science Inventory

The Models-3/CMAQ developed by the U.S. Environmental Protections Agency (USEPA) is a third generation multiscale, multi-pollutant air quality modeling system within a high-level, object-oriented computer framework (Models-3). It has been available to the scientific community ...

Implementation of density functional theory method on object-oriented programming (C++) to calculate energy band structure using the projector augmented wave (PAW)

NASA Astrophysics Data System (ADS)

Alfianto, E.; Rusydi, F.; Aisyah, N. D.; Fadilla, R. N.; Dipojono, H. K.; Martoprawiro, M. A.

2017-05-01

This study implemented DFT method into the C++ programming language with object-oriented programming rules (expressive software). The use of expressive software results in getting a simple programming structure, which is similar to mathematical formula. This will facilitate the scientific community to develop the software. We validate our software by calculating the energy band structure of Silica, Carbon, and Germanium with FCC structure using the Projector Augmented Wave (PAW) method then compare the results to Quantum Espresso calculation’s results. This study shows that the accuracy of the software is 85% compared to Quantum Espresso.

International Trade Professional Curriculum System Innovation and Personnel Training Model Exploration

NASA Astrophysics Data System (ADS)

Xiao, Yang

With the rapid development of China's foreign trade, now many universities have set up the International Trade major one after another; The University must be based on our own resources superiority to have the scientific orientation of personnel training objectives, which can make trained students meet needs of society and enterprises better. This paper based on the characteristics of International Trade major in University proposes to take the personnel training model combining with "Work, Certificate and Learning" as the objective, proceeding the orientation of professional personnel and settings of certificate testing module and teaching module, to construct the curriculum system from the innovation of theoretical and practical teaching.

MCdevelop - a universal framework for Stochastic Simulations

NASA Astrophysics Data System (ADS)

Slawinska, M.; Jadach, S.

2011-03-01

We present MCdevelop, a universal computer framework for developing and exploiting the wide class of Stochastic Simulations (SS) software. This powerful universal SS software development tool has been derived from a series of scientific projects for precision calculations in high energy physics (HEP), which feature a wide range of functionality in the SS software needed for advanced precision Quantum Field Theory calculations for the past LEP experiments and for the ongoing LHC experiments at CERN, Geneva. MCdevelop is a "spin-off" product of HEP to be exploited in other areas, while it will still serve to develop new SS software for HEP experiments. Typically SS involve independent generation of large sets of random "events", often requiring considerable CPU power. Since SS jobs usually do not share memory it makes them easy to parallelize. The efficient development, testing and running in parallel SS software requires a convenient framework to develop software source code, deploy and monitor batch jobs, merge and analyse results from multiple parallel jobs, even before the production runs are terminated. Throughout the years of development of stochastic simulations for HEP, a sophisticated framework featuring all the above mentioned functionality has been implemented. MCdevelop represents its latest version, written mostly in C++ (GNU compiler gcc). It uses Autotools to build binaries (optionally managed within the KDevelop 3.5.3 Integrated Development Environment (IDE)). It uses the open-source ROOT package for histogramming, graphics and the mechanism of persistency for the C++ objects. MCdevelop helps to run multiple parallel jobs on any computer cluster with NQS-type batch system. Program summaryProgram title:MCdevelop Catalogue identifier: AEHW_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 48 136 No. of bytes in distributed program, including test data, etc.: 355 698 Distribution format: tar.gz Programming language: ANSI C++ Computer: Any computer system or cluster with C++ compiler and UNIX-like operating system. Operating system: Most UNIX systems, Linux. The application programs were thoroughly tested under Ubuntu 7.04, 8.04 and CERN Scientific Linux 5. Has the code been vectorised or parallelised?: Tools (scripts) for optional parallelisation on a PC farm are included. RAM: 500 bytes Classification: 11.3 External routines: ROOT package version 5.0 or higher ( http://root.cern.ch/drupal/). Nature of problem: Developing any type of stochastic simulation program for high energy physics and other areas. Solution method: Object Oriented programming in C++ with added persistency mechanism, batch scripts for running on PC farms and Autotools.

Using CLIPS in the domain of knowledge-based massively parallel programming

NASA Technical Reports Server (NTRS)

Dvorak, Jiri J.

1994-01-01

The Program Development Environment (PDE) is a tool for massively parallel programming of distributed-memory architectures. Adopting a knowledge-based approach, the PDE eliminates the complexity introduced by parallel hardware with distributed memory and offers complete transparency in respect of parallelism exploitation. The knowledge-based part of the PDE is realized in CLIPS. Its principal task is to find an efficient parallel realization of the application specified by the user in a comfortable, abstract, domain-oriented formalism. A large collection of fine-grain parallel algorithmic skeletons, represented as COOL objects in a tree hierarchy, contains the algorithmic knowledge. A hybrid knowledge base with rule modules and procedural parts, encoding expertise about application domain, parallel programming, software engineering, and parallel hardware, enables a high degree of automation in the software development process. In this paper, important aspects of the implementation of the PDE using CLIPS and COOL are shown, including the embedding of CLIPS with C++-based parts of the PDE. The appropriateness of the chosen approach and of the CLIPS language for knowledge-based software engineering are discussed.

High-performance parallel analysis of coupled problems for aircraft propulsion

NASA Technical Reports Server (NTRS)

Felippa, C. A.; Farhat, C.; Lanteri, S.; Gumaste, U.; Ronaghi, M.

1994-01-01

Applications are described of high-performance parallel, computation for the analysis of complete jet engines, considering its multi-discipline coupled problem. The coupled problem involves interaction of structures with gas dynamics, heat conduction and heat transfer in aircraft engines. The methodology issues addressed include: consistent discrete formulation of coupled problems with emphasis on coupling phenomena; effect of partitioning strategies, augmentation and temporal solution procedures; sensitivity of response to problem parameters; and methods for interfacing multiscale discretizations in different single fields. The computer implementation issues addressed include: parallel treatment of coupled systems; domain decomposition and mesh partitioning strategies; data representation in object-oriented form and mapping to hardware driven representation, and tradeoff studies between partitioning schemes and fully coupled treatment.

A new method for recognizing quadric surfaces from range data and its application to telerobotics and automation

NASA Technical Reports Server (NTRS)

Alvertos, Nicolas; Dcunha, Ivan

1992-01-01

A feature set of two dimensional curves is obtained after intersecting symmetric objects like spheres, cones, cylinders, ellipsoids, paraboloids, and parallelepipeds with two planes. After determining the location and orientation of the objects in space, these objects are aligned so as to lie on a plane parallel to a suitable coordinate system. These objects are then intersected with a horizontal and a vertical plane. Experiments were carried out with range images of sphere and cylinder. The 3-D discriminant approach was used to recognize quadric surfaces made up of simulated data. Its application to real data was also studied.

Automated quantification of neurite outgrowth orientation distributions on patterned surfaces

NASA Astrophysics Data System (ADS)

Payne, Matthew; Wang, Dadong; Sinclair, Catriona M.; Kapsa, Robert M. I.; Quigley, Anita F.; Wallace, Gordon G.; Razal, Joselito M.; Baughman, Ray H.; Münch, Gerald; Vallotton, Pascal

2014-08-01

Objective. We have developed an image analysis methodology for quantifying the anisotropy of neuronal projections on patterned substrates. Approach. Our method is based on the fitting of smoothing splines to the digital traces produced using a non-maximum suppression technique. This enables precise estimates of the local tangents uniformly along the neurite length, and leads to unbiased orientation distributions suitable for objectively assessing the anisotropy induced by tailored surfaces. Main results. In our application, we demonstrate that carbon nanotubes arrayed in parallel bundles over gold surfaces induce a considerable neurite anisotropy; a result which is relevant for regenerative medicine. Significance. Our pipeline is generally applicable to the study of fibrous materials on 2D surfaces and should also find applications in the study of DNA, microtubules, and other polymeric materials.

ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data

DOE PAGES

Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S.; ...

2017-02-23

Here, a newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides,more » important for metal extraction chemistry, are parametrized using ParFit.« less

ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S.

Here, a newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides,more » important for metal extraction chemistry, are parametrized using ParFit.« less

A class Hierarchical, object-oriented approach to virtual memory management

NASA Technical Reports Server (NTRS)

Russo, Vincent F.; Campbell, Roy H.; Johnston, Gary M.

1989-01-01

The Choices family of operating systems exploits class hierarchies and object-oriented programming to facilitate the construction of customized operating systems for shared memory and networked multiprocessors. The software is being used in the Tapestry laboratory to study the performance of algorithms, mechanisms, and policies for parallel systems. Described here are the architectural design and class hierarchy of the Choices virtual memory management system. The software and hardware mechanisms and policies of a virtual memory system implement a memory hierarchy that exploits the trade-off between response times and storage capacities. In Choices, the notion of a memory hierarchy is captured by abstract classes. Concrete subclasses of those abstractions implement a virtual address space, segmentation, paging, physical memory management, secondary storage, and remote (that is, networked) storage. Captured in the notion of a memory hierarchy are classes that represent memory objects. These classes provide a storage mechanism that contains encapsulated data and have methods to read or write the memory object. Each of these classes provides specializations to represent the memory hierarchy.

Polarized object detection in crabs: a two-channel system.

PubMed

Basnak, Melanie Ailín; Pérez-Schuster, Verónica; Hermitte, Gabriela; Berón de Astrada, Martín

2018-05-25

Many animal species take advantage of polarization vision for vital tasks such as orientation, communication and contrast enhancement. Previous studies have suggested that decapod crustaceans use a two-channel polarization system for contrast enhancement. Here, we characterize the polarization contrast sensitivity in a grapsid crab . We estimated the polarization contrast sensitivity of the animals by quantifying both their escape response and changes in heart rate when presented with polarized motion stimuli. The motion stimulus consisted of an expanding disk with an 82 deg polarization difference between the object and the background. More than 90% of animals responded by freezing or trying to avoid the polarized stimulus. In addition, we co-rotated the electric vector (e-vector) orientation of the light from the object and background by increments of 30 deg and found that the animals' escape response varied periodically with a 90 deg period. Maximum escape responses were obtained for object and background e-vectors near the vertical and horizontal orientations. Changes in cardiac response showed parallel results but also a minimum response when e-vectors of object and background were shifted by 45 deg with respect to the maxima. These results are consistent with an orthogonal receptor arrangement for the detection of polarized light, in which two channels are aligned with the vertical and horizontal orientations. It has been hypothesized that animals with object-based polarization vision rely on a two-channel detection system analogous to that of color processing in dichromats. Our results, obtained by systematically varying the e-vectors of object and background, provide strong empirical support for this theoretical model of polarized object detection. © 2018. Published by The Company of Biologists Ltd.

The cost of parallel consolidation into visual working memory.

PubMed

Rideaux, Reuben; Edwards, Mark

2016-01-01

A growing body of evidence indicates that information can be consolidated into visual working memory in parallel. Initially, it was suggested that color information could be consolidated in parallel while orientation was strictly limited to serial consolidation (Liu & Becker, 2013). However, we recently found evidence suggesting that both orientation and motion direction items can be consolidated in parallel, with different levels of accuracy (Rideaux, Apthorp, & Edwards, 2015). Here we examine whether there is a cost associated with parallel consolidation of orientation and direction information by comparing performance, in terms of precision and guess rate, on a target recall task where items are presented either sequentially or simultaneously. The results compellingly indicate that motion direction can be consolidated in parallel, but the evidence for orientation is less conclusive. Further, we find that there is a twofold cost associated with parallel consolidation of direction: Both the probability of failing to consolidate one (or both) item/s increases and the precision at which representations are encoded is reduced. Additionally, we find evidence indicating that the increased consolidation failure may be due to interference between items presented simultaneously, and is moderated by item similarity. These findings suggest that a biased competition model may explain differences in parallel consolidation between features.

Augmented assessment as a means to augmented reality.

PubMed

Bergeron, Bryan

2006-01-01

Rigorous scientific assessment of educational technologies typically lags behind the availability of the technologies by years because of the lack of validated instruments and benchmarks. Even when the appropriate assessment instruments are available, they may not be applied because of time and monetary constraints. Work in augmented reality, instrumented mannequins, serious gaming, and similar promising educational technologies that haven't undergone timely, rigorous evaluation, highlights the need for assessment methodologies that address the limitations of traditional approaches. The most promising augmented assessment solutions incorporate elements of rapid prototyping used in the software industry, simulation-based assessment techniques modeled after methods used in bioinformatics, and object-oriented analysis methods borrowed from object oriented programming.

Parallel basal ganglia circuits for voluntary and automatic behaviour to reach rewards

PubMed Central

Hikosaka, Okihide

2015-01-01

The basal ganglia control body movements, value processing and decision-making. Many studies have shown that the inputs and outputs of each basal ganglia structure are topographically organized, which suggests that the basal ganglia consist of separate circuits that serve distinct functions. A notable example is the circuits that originate from the rostral (head) and caudal (tail) regions of the caudate nucleus, both of which target the superior colliculus. These two caudate regions encode the reward values of visual objects differently: flexible (short-term) values by the caudate head and stable (long-term) values by the caudate tail. These value signals in the caudate guide the orienting of gaze differently: voluntary saccades by the caudate head circuit and automatic saccades by the caudate tail circuit. Moreover, separate groups of dopamine neurons innervate the caudate head and tail and may selectively guide the flexible and stable learning/memory in the caudate regions. Studies focusing on manual handling of objects also suggest that rostrocaudally separated circuits in the basal ganglia control the action differently. These results suggest that the basal ganglia contain parallel circuits for two steps of goal-directed behaviour: finding valuable objects and manipulating the valuable objects. These parallel circuits may underlie voluntary behaviour and automatic skills, enabling animals (including humans) to adapt to both volatile and stable environments. This understanding of the functions and mechanisms of the basal ganglia parallel circuits may inform the differential diagnosis and treatment of basal ganglia disorders. PMID:25981958

Overview of Computer Simulation Modeling Approaches and Methods

Treesearch

Robert E. Manning; Robert M. Itami; David N. Cole; Randy Gimblett

2005-01-01

The field of simulation modeling has grown greatly with recent advances in computer hardware and software. Much of this work has involved large scientific and industrial applications for which substantial financial resources are available. However, advances in object-oriented programming and simulation methodology, concurrent with dramatic increases in computer...

Problem Orientation in Physical Geography Teaching.

ERIC Educational Resources Information Center

Church, Michael

1988-01-01

States that the introduction of real, quantitative problems in classroom and field teaching improves scientific rigor and leads more directly to applied studies. Examines the use of problems in an introductory hydrology course, presenting teaching objectives and the full course structure to illustrate their integration with other teaching modes.…

Core-Oriented Lexical Translation Evaluation (COLTE)

ERIC Educational Resources Information Center

Jahangiri, A. M.

1998-01-01

Objective measurement in translation evaluation is a relatively untouched area, especially at the level of the lexis. No thoroughly worked-out method has been put forward for the scientific evaluation of a translation. Yet few translators would question the potential value of such a device. Certainly translation evaluation is not limited to the…

The open-source movement: an introduction for forestry professionals

Treesearch

Patrick Proctor; Paul C. Van Deusen; Linda S. Heath; Jeffrey H. Gove

2005-01-01

In recent years, the open-source movement has yielded a generous and powerful suite of software and utilities that rivals those developed by many commercial software companies. Open-source programs are available for many scientific needs: operating systems, databases, statistical analysis, Geographic Information System applications, and object-oriented programming....

The future scientific CCD

NASA Technical Reports Server (NTRS)

Janesick, J. R.; Elliott, T.; Collins, S.; Marsh, H.; Blouke, M. M.

1984-01-01

Since the first introduction of charge-coupled devices (CCDs) in 1970, CCDs have been considered for applications related to memories, logic circuits, and the detection of visible radiation. It is pointed out, however, that the mass market orientation of CCD development has left largely untapped the enormous potential of these devices for advanced scientific instrumentation. The present paper has, therefore, the objective to introduce the CCD characteristics to the scientific community, taking into account prospects for further improvement. Attention is given to evaluation criteria, a summary of current CCDs, CCD performance characteristics, absolute calibration tools, quantum efficiency, aspects of charge collection, charge transfer efficiency, read noise, and predictions regarding the characteristics of the next generation of silicon scientific CCD imagers.

Tracking-Data-Conversion Tool

NASA Technical Reports Server (NTRS)

Flora-Adams, Dana; Makihara, Jeanne; Benenyan, Zabel; Berner, Jeff; Kwok, Andrew

2007-01-01

Object Oriented Data Technology (OODT) is a software framework for creating a Web-based system for exchange of scientific data that are stored in diverse formats on computers at different sites under the management of scientific peers. OODT software consists of a set of cooperating, distributed peer components that provide distributed peer-topeer (P2P) services that enable one peer to search and retrieve data managed by another peer. In effect, computers running OODT software at different locations become parts of an integrated data-management system.

Software Framework for Peer Data-Management Services

NASA Technical Reports Server (NTRS)

Hughes, John; Hardman, Sean; Crichton, Daniel; Hyon, Jason; Kelly, Sean; Tran, Thuy

2007-01-01

Object Oriented Data Technology (OODT) is a software framework for creating a Web-based system for exchange of scientific data that are stored in diverse formats on computers at different sites under the management of scientific peers. OODT software consists of a set of cooperating, distributed peer components that provide distributed peer-to-peer (P2P) services that enable one peer to search and retrieve data managed by another peer. In effect, computers running OODT software at different locations become parts of an integrated data-management system.

The effects of incidence angle on film dosimetry and their consequences in IMRT dose verification.

PubMed

Srivastava, R P; De Wagter, C

2012-10-01

The dosimetric accuracy of EDR2 radiographic film has been rigorously assessed in regular and intensity modulated beams for various incidence angles, including the parallel and perpendicular orientation. There clearly exists confusion in literature regarding the effect of film orientation. The primary aim is to clarify potential sources of the confusion and to gain physical insight into the film orientation effect with a link to radiochromic film as well. An inverse pyramid IMRT field, consisting of six regular and elongated 3 × 20 cm(2) field segments, was studied in perpendicular and parallel orientation. Assessment of film self-perturbation and intrinsic directional sensitivity were also included in the experiments. Finally, the authors investigated the orientational effect in composite beams in the two extreme orientations, i.e., perpendicular and parallel. The study of an inverse pyramid dose profile revealed good agreement between the perpendicular film and the diamond detector within 0.5% in the low-scatter regions for both 6 and 18 MV. The parallel oriented film demonstrated a 3% under-response at 5-cm (6 MV) depth against the perpendicular orientation, but both orientations over responded equally in the central region, which received only scattered dose, at both 5- and 20-cm depths. In a regular 6-MV 5 × 5 cm(2) field, a 4.1% lower film response was observed in the parallel orientation compared to perpendicular orientation. The under response gradually increased to 6% when reducing the field size to 0.5 × 5 cm(2). On the other hand, the film showed a 1.7% lower response in parallel orientation for the large field size of 20 × 20 cm(2) at 5-cm depth but the difference disappeared at 10 cm. At 18 MV, similar but somewhat lower differences were found between the two orientations. The directional sensitivity of the film diminishes with increasing field size and depth. Surprisingly a composite IMRT beam consisting of 20 adjacent strip segments also produced a significant orientational dependence of film response, notwithstanding the large total field size of 20 × 20 cm(2). This analysis allowed the development of a hypothesis about the physics behind the orientational dependence of film response in general and to formulate precautions when using film dosimetry in the dosimetric verification of multibeam treatments.

[Three-dimensional parallel collagen scaffold promotes tendon extracellular matrix formation].

PubMed

Zheng, Zefeng; Shen, Weiliang; Le, Huihui; Dai, Xuesong; Ouyang, Hongwei; Chen, Weishan

2016-03-01

To investigate the effects of three-dimensional parallel collagen scaffold on the cell shape, arrangement and extracellular matrix formation of tendon stem cells. Parallel collagen scaffold was fabricated by unidirectional freezing technique, while random collagen scaffold was fabricated by freeze-drying technique. The effects of two scaffolds on cell shape and extracellular matrix formation were investigated in vitro by seeding tendon stem/progenitor cells and in vivo by ectopic implantation. Parallel and random collagen scaffolds were produced successfully. Parallel collagen scaffold was more akin to tendon than random collagen scaffold. Tendon stem/progenitor cells were spindle-shaped and unified orientated in parallel collagen scaffold, while cells on random collagen scaffold had disorder orientation. Two weeks after ectopic implantation, cells had nearly the same orientation with the collagen substance. In parallel collagen scaffold, cells had parallel arrangement, and more spindly cells were observed. By contrast, cells in random collagen scaffold were disorder. Parallel collagen scaffold can induce cells to be in spindly and parallel arrangement, and promote parallel extracellular matrix formation; while random collagen scaffold can induce cells in random arrangement. The results indicate that parallel collagen scaffold is an ideal structure to promote tendon repairing.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jain, Atul K.

The overall objectives of this DOE funded project is to combine scientific and computational challenges in climate modeling by expanding our understanding of the biogeophysical-biogeochemical processes and their interactions in the northern high latitudes (NHLs) using an earth system modeling (ESM) approach, and by adopting an adaptive parallel runtime system in an ESM to achieve efficient and scalable climate simulations through improved load balancing algorithms.

Separating the Laparoscopic Camera Cord From the Monopolar "Bovie" Cord Reduces Unintended Thermal Injury From Antenna Coupling: A Randomized Controlled Trial.

PubMed

Robinson, Thomas N; Jones, Edward L; Dunn, Christina L; Dunne, Bruce; Johnson, Elizabeth; Townsend, Nicole T; Paniccia, Alessandro; Stiegmann, Greg V

2015-06-01

The monopolar "Bovie" is used in virtually every laparoscopic operation. The active electrode and its cord emit radiofrequency energy that couples (or transfers) to nearby conductive material without direct contact. This phenomenon is increased when the active electrode cord is oriented parallel to another wire/cord. The parallel orientation of the "Bovie" and laparoscopic camera cords cause transfer of energy to the camera cord resulting in cutaneous burns at the camera trocar incision. We hypothesized that separating the active electrode/camera cords would reduce thermal injury occurring at the camera trocar incision in comparison to parallel oriented active electrode/camera cords. In this prospective, blinded, randomized controlled trial, patients undergoing standardized laparoscopic cholecystectomy were randomized to separated active electrode/camera cords or parallel oriented active electrode/camera cords. The primary outcome variable was thermal injury determined by histology from skin biopsied at the camera trocar incision. Eighty-four patients participated. Baseline demographics were similar in the groups for age, sex, preoperative diagnosis, operative time, and blood loss. Thermal injury at the camera trocar incision was lower in the separated versus parallel group (31% vs 57%; P = 0.027). Separation of the laparoscopic camera cord from the active electrode cord decreases thermal injury from antenna coupling at the camera trocar incision in comparison to the parallel orientation of these cords. Therefore, parallel orientation of these cords (an arrangement promoted by integrated operating rooms) should be abandoned. The findings of this study should influence the operating room setup for all laparoscopic cases.

Toward Transparent Data Management in Multi-layer Storage Hierarchy for HPC Systems

DOE PAGES

Wadhwa, Bharti; Byna, Suren; Butt, Ali R.

2018-04-17

Upcoming exascale high performance computing (HPC) systems are expected to comprise multi-tier storage hierarchy, and thus will necessitate innovative storage and I/O mechanisms. Traditional disk and block-based interfaces and file systems face severe challenges in utilizing capabilities of storage hierarchies due to the lack of hierarchy support and semantic interfaces. Object-based and semantically-rich data abstractions for scientific data management on large scale systems offer a sustainable solution to these challenges. Such data abstractions can also simplify users involvement in data movement. Here, we take the first steps of realizing such an object abstraction and explore storage mechanisms for these objectsmore » to enhance I/O performance, especially for scientific applications. We explore how an object-based interface can facilitate next generation scalable computing systems by presenting the mapping of data I/O from two real world HPC scientific use cases: a plasma physics simulation code (VPIC) and a cosmology simulation code (HACC). Our storage model stores data objects in different physical organizations to support data movement across layers of memory/storage hierarchy. Our implementation sclaes well to 16K parallel processes, and compared to the state of the art, such as MPI-IO and HDF5, our object-based data abstractions and data placement strategy in multi-level storage hierarchy achieves up to 7 X I/O performance improvement for scientific data.« less

Toward Transparent Data Management in Multi-layer Storage Hierarchy for HPC Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wadhwa, Bharti; Byna, Suren; Butt, Ali R.

Upcoming exascale high performance computing (HPC) systems are expected to comprise multi-tier storage hierarchy, and thus will necessitate innovative storage and I/O mechanisms. Traditional disk and block-based interfaces and file systems face severe challenges in utilizing capabilities of storage hierarchies due to the lack of hierarchy support and semantic interfaces. Object-based and semantically-rich data abstractions for scientific data management on large scale systems offer a sustainable solution to these challenges. Such data abstractions can also simplify users involvement in data movement. Here, we take the first steps of realizing such an object abstraction and explore storage mechanisms for these objectsmore » to enhance I/O performance, especially for scientific applications. We explore how an object-based interface can facilitate next generation scalable computing systems by presenting the mapping of data I/O from two real world HPC scientific use cases: a plasma physics simulation code (VPIC) and a cosmology simulation code (HACC). Our storage model stores data objects in different physical organizations to support data movement across layers of memory/storage hierarchy. Our implementation sclaes well to 16K parallel processes, and compared to the state of the art, such as MPI-IO and HDF5, our object-based data abstractions and data placement strategy in multi-level storage hierarchy achieves up to 7 X I/O performance improvement for scientific data.« less

A Parallel Rendering Algorithm for MIMD Architectures

NASA Technical Reports Server (NTRS)

Crockett, Thomas W.; Orloff, Tobias

1991-01-01

Applications such as animation and scientific visualization demand high performance rendering of complex three dimensional scenes. To deliver the necessary rendering rates, highly parallel hardware architectures are required. The challenge is then to design algorithms and software which effectively use the hardware parallelism. A rendering algorithm targeted to distributed memory MIMD architectures is described. For maximum performance, the algorithm exploits both object-level and pixel-level parallelism. The behavior of the algorithm is examined both analytically and experimentally. Its performance for large numbers of processors is found to be limited primarily by communication overheads. An experimental implementation for the Intel iPSC/860 shows increasing performance from 1 to 128 processors across a wide range of scene complexities. It is shown that minimal modifications to the algorithm will adapt it for use on shared memory architectures as well.

Nerve Cells Decide to Orient inside an Injectable Hydrogel with Minimal Structural Guidance.

PubMed

Rose, Jonas C; Cámara-Torres, María; Rahimi, Khosrow; Köhler, Jens; Möller, Martin; De Laporte, Laura

2017-06-14

Injectable biomaterials provide the advantage of a minimally invasive application but mostly lack the required structural complexity to regenerate aligned tissues. Here, we report a new class of tissue regenerative materials that can be injected and form an anisotropic matrix with controlled dimensions using rod-shaped, magnetoceptive microgel objects. Microgels are doped with small quantities of superparamagnetic iron oxide nanoparticles (0.0046 vol %), allowing alignment by external magnetic fields in the millitesla order. The microgels are dispersed in a biocompatible gel precursor and after injection and orientation are fixed inside the matrix hydrogel. Regardless of the low volume concentration of the microgels below 3%, at which the geometrical constrain for orientation is still minimum, the generated macroscopic unidirectional orientation is strongly sensed by the cells resulting in parallel nerve extension. This finding opens a new, minimal invasive route for therapy after spinal cord injury.

Experimental and modelling study of the effect of airflow orientation with respect to strip electrode on ozone production of surface dielectric barrier discharge

NASA Astrophysics Data System (ADS)

Mikeš, J.; Pekárek, S.; Soukup, I.

2016-11-01

This study examines the effect of airflow orientation with respect to the strip active electrode on concentration of ozone and nitrogen dioxide produced in a planar generator based on the surface dielectric barrier discharge. The orientation of the airflow was tested in parallel and perpendicular with respect to the strips. It was found that in the investigated range of average discharge power, the ozone concentration increases approximately by 25% when airflow was oriented in parallel with respect to the strips in comparison with perpendicular orientation of the airflow. Similarly the increase of nitrogen dioxide concentration was observed for parallel orientation of the airflow with respect to the strips in comparison with the perpendicular orientation of the airflow. Within the range of wavelengths from 250 to 1100 nm, the changes of intensities of spectral lines associated with airflow orientation have been observed. A 3D numerical model describing ion trajectories and airflow patterns have also been developed.

Validation of Shear Wave Elastography in Skeletal Muscle

PubMed Central

Eby, Sarah F.; Song, Pengfei; Chen, Shigao; Chen, Qingshan; Greenleaf, James F.; An, Kai-Nan

2013-01-01

Skeletal muscle is a very dynamic tissue, thus accurate quantification of skeletal muscle stiffness throughout its functional range is crucial to improve the physical functioning and independence following pathology. Shear wave elastography (SWE) is an ultrasound-based technique that characterizes tissue mechanical properties based on the propagation of remotely induced shear waves. The objective of this study is to validate SWE throughout the functional range of motion of skeletal muscle for three ultrasound transducer orientations. We hypothesized that combining traditional materials testing (MTS) techniques with SWE measurements will show increased stiffness measures with increasing tensile load, and will correlate well with each other for trials in which the transducer is parallel to underlying muscle fibers. To evaluate this hypothesis, we monitored the deformation throughout tensile loading of four porcine brachialis whole-muscle tissue specimens, while simultaneously making SWE measurements of the same specimen. We used regression to examine the correlation between Young's modulus from MTS and shear modulus from SWE for each of the transducer orientations. We applied a generalized linear model to account for repeated testing. Model parameters were estimated via generalized estimating equations. The regression coefficient was 0.1944, with a 95% confidence interval of (0.1463 – 0.2425) for parallel transducer trials. Shear waves did not propagate well for both the 45° and perpendicular transducer orientations. Both parallel SWE and MTS showed increased stiffness with increasing tensile load. This study provides the necessary first step for additional studies that can evaluate the distribution of stiffness throughout muscle. PMID:23953670

Magnocellular pathway for rotation invariant Neocognitron.

PubMed

Ting, C H

1993-03-01

In the mammalian visual system, magnocellular pathway and parvocellular pathway cooperatively process visual information in parallel. The magnocellular pathway is more global and less particular about the details while the parvocellular pathway recognizes objects based on the local features. In many aspects, Neocognitron may be regarded as the artificial analogue of the parvocellular pathway. It is interesting then to model the magnocellular pathway. In order to achieve "rotation invariance" for Neocognitron, we propose a neural network model after the magnocellular pathway and expand its roles to include surmising the orientation of the input pattern prior to recognition. With the incorporation of the magnocellular pathway, a basic shift in the original paradigm has taken place. A pattern is now said to be recognized when and only when one of the winners of the magnocellular pathway is validified by the parvocellular pathway. We have implemented the magnocellular pathway coupled with Neocognitron parallel on transputers; our simulation programme is now able to recognize numerals in arbitrary orientation.

Apodized Pupil Lyot Coronagraphs designs for future segmented space telescopes

NASA Astrophysics Data System (ADS)

St. Laurent, Kathryn; Fogarty, Kevin; Zimmerman, Neil; N’Diaye, Mamadou; Stark, Chris; Sivaramakrishnan, Anand; Pueyo, Laurent; Vanderbei, Robert; Soummer, Remi

2018-01-01

A coronagraphic starlight suppression system situated on a future flagship space observatory offers a promising avenue to image Earth-like exoplanets and search for biomarkers in their atmospheric spectra. One NASA mission concept that could serve as the platform to realize this scientific breakthrough is the Large UV/Optical/IR Surveyor (LUVOIR). Such a mission would also address a broad range of topics in astrophysics with a multi-wavelength suite of instruments.In support of the community’s assessment of the scientific capability of a LUVOIR mission, the Exoplanet Exploration Program (ExEP) has launched a multi-team technical study: Segmented Coronagraph Design and Analysis (SCDA). The goal of this study is to develop viable coronagraph instrument concepts for a LUVOIR-type mission. Results of the SCDA effort will directly inform the mission concept evaluation being carried out by the LUVOIR Science and Technology Definition Team. The apodized pupil Lyot coronagraph (APLC) is one of several coronagraph design families that the SCDA study is assessing. The APLC is a Lyot-style coronagraph that suppresses starlight through a series of amplitude operations on the on-axis field. Given a suite of seven plausible segmented telescope apertures, we have developed an object-oriented software toolkit to automate the exploration of thousands of APLC design parameter combinations. In the course of exploring this parameter space we have established relationships between APLC throughput and telescope aperture geometry, Lyot stop, inner working angle, bandwidth, and contrast level. In parallel with the parameter space exploration, we have investigated several strategies to improve the robustness of APLC designs to fabrication and alignment errors and integrated a Design Reference Mission framework to evaluate designs with scientific yield metrics.

Digital Archive Issues from the Perspective of an Earth Science Data Producer

NASA Technical Reports Server (NTRS)

Barkstrom, Bruce R.

2004-01-01

Contents include the following: Introduction. A Producer Perspective on Earth Science Data. Data Producers as Members of a Scientific Community. Some Unique Characteristics of Scientific Data. Spatial and Temporal Sampling for Earth (or Space) Science Data. The Influence of the Data Production System Architecture. The Spatial and Temporal Structures Underlying Earth Science Data. Earth Science Data File (or Relation) Schemas. Data Producer Configuration Management Complexities. The Topology of Earth Science Data Inventories. Some Thoughts on the User Perspective. Science Data User Communities. Spatial and Temporal Structure Needs of Different Users. User Spatial Objects. Data Search Services. Inventory Search. Parameter (Keyword) Search. Metadata Searches. Documentation Search. Secondary Index Search. Print Technology and Hypertext. Inter-Data Collection Configuration Management Issues. An Archive View. Producer Data Ingest and Production. User Data Searching and Distribution. Subsetting and Supersetting. Semantic Requirements for Data Interchange. Tentative Conclusions. An Object Oriented View of Archive Information Evolution. Scientific Data Archival Issues. A Perspective on the Future of Digital Archives for Scientific Data. References Index for this paper.

Electromagnetic pulse scattering by a spacecraft nearing light speed.

PubMed

Garner, Timothy J; Lakhtakia, Akhlesh; Breakall, James K; Bohren, Craig F

2017-08-01

Humans will launch spacecraft that travel at an appreciable fraction of the speed of light. Spacecraft traffic will be tracked by radar. Scattering of pulsed electromagnetic fields by an object in uniform translational motion at relativistic speed may be computed using the frame-hopping technique. Pulse scattering depends strongly on the velocity, shape, orientation, and composition of the object. The peak magnitude of the backscattered signal varies by many orders of magnitude, depending on whether the object is advancing toward or receding from the source of the interrogating signal. The peak magnitude of the backscattered signal goes to zero as the object recedes from the observer at a speed very closely approaching light speed, rendering the object invisible to the observer. The energy scattered by an object in motion may increase or decrease relative to the energy scattered by the same object at rest. Both the magnitude and sign of the change depend on the velocity of the object, as well as on its shape, orientation, and composition. In some cases, the change in total scattered energy is greatest when the object is moving transversely to the propagation direction of the interrogating signal, even though the Doppler effect is strongest when the motion is parallel or antiparallel to the propagation direction.

High-Frequency Replanning Under Uncertainty Using Parallel Sampling-Based Motion Planning

PubMed Central

Sun, Wen; Patil, Sachin; Alterovitz, Ron

2015-01-01

As sampling-based motion planners become faster, they can be re-executed more frequently by a robot during task execution to react to uncertainty in robot motion, obstacle motion, sensing noise, and uncertainty in the robot’s kinematic model. We investigate and analyze high-frequency replanning (HFR), where, during each period, fast sampling-based motion planners are executed in parallel as the robot simultaneously executes the first action of the best motion plan from the previous period. We consider discrete-time systems with stochastic nonlinear (but linearizable) dynamics and observation models with noise drawn from zero mean Gaussian distributions. The objective is to maximize the probability of success (i.e., avoid collision with obstacles and reach the goal) or to minimize path length subject to a lower bound on the probability of success. We show that, as parallel computation power increases, HFR offers asymptotic optimality for these objectives during each period for goal-oriented problems. We then demonstrate the effectiveness of HFR for holonomic and nonholonomic robots including car-like vehicles and steerable medical needles. PMID:26279645

RF control at SSCL — an object oriented design approach

NASA Astrophysics Data System (ADS)

Dohan, D. A.; Osberg, E.; Biggs, R.; Bossom, J.; Chillara, K.; Richter, R.; Wade, D.

1994-12-01

The Superconducting Super Collider (SSC) in Texas, the construction of which was stopped in 1994, would have represented a major challenge in accelerator research and development. This paper addresses the issues encountered in the parallel design and construction of the control systems for the RF equipment for the five accelerators comprising the SSC. An extensive analysis of the components of the RF control systems has been undertaken, based upon the Schlaer-Mellor object-oriented analysis and design (OOA/OOD) methodology. The RF subsystem components such as amplifiers, tubes, power supplies, PID loops, etc. were analyzed to produce OOA information, behavior and process models. Using these models, OOD was iteratively applied to develop a generic RF control system design. This paper describes the results of this analysis and the development of 'bridges' between the analysis objects, and the EPICS-based software and underlying VME-based hardware architectures. The application of this approach to several of the SSCL RF control systems is discussed.

Extending Automatic Parallelization to Optimize High-Level Abstractions for Multicore

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liao, C; Quinlan, D J; Willcock, J J

2008-12-12

Automatic introduction of OpenMP for sequential applications has attracted significant attention recently because of the proliferation of multicore processors and the simplicity of using OpenMP to express parallelism for shared-memory systems. However, most previous research has only focused on C and Fortran applications operating on primitive data types. C++ applications using high-level abstractions, such as STL containers and complex user-defined types, are largely ignored due to the lack of research compilers that are readily able to recognize high-level object-oriented abstractions and leverage their associated semantics. In this paper, we automatically parallelize C++ applications using ROSE, a multiple-language source-to-source compiler infrastructuremore » which preserves the high-level abstractions and gives us access to their semantics. Several representative parallelization candidate kernels are used to explore semantic-aware parallelization strategies for high-level abstractions, combined with extended compiler analyses. Those kernels include an array-base computation loop, a loop with task-level parallelism, and a domain-specific tree traversal. Our work extends the applicability of automatic parallelization to modern applications using high-level abstractions and exposes more opportunities to take advantage of multicore processors.« less

A microkernel design for component-based parallel numerical software systems.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balay, S.

1999-01-13

What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the file system or network. The microkernel required to manage such a system needs to include, at most: (1) a few basic services, namely--a mechanism for loading objects at run time via dynamic link libraries, and consistent schemes for error handling and memory management; and (2) selected methods that all objectsmore » share, to deal with object life (destruction, reference counting, relationships), and object observation (viewing, profiling, tracing). We are experimenting with these ideas in the context of extensible numerical software within the ALICE (Advanced Large-scale Integrated Computational Environment) project, where we are building the microkernel to manage the interoperability among various tools for large-scale scientific simulations. This paper presents some preliminary observations and conclusions from our work with microkernel design.« less

mm_par2.0: An object-oriented molecular dynamics simulation program parallelized using a hierarchical scheme with MPI and OPENMP

NASA Astrophysics Data System (ADS)

Oh, Kwang Jin; Kang, Ji Hoon; Myung, Hun Joo

2012-02-01

We have revised a general purpose parallel molecular dynamics simulation program mm_par using the object-oriented programming. We parallelized the revised version using a hierarchical scheme in order to utilize more processors for a given system size. The benchmark result will be presented here. New version program summaryProgram title: mm_par2.0 Catalogue identifier: ADXP_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXP_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 2 390 858 No. of bytes in distributed program, including test data, etc.: 25 068 310 Distribution format: tar.gz Programming language: C++ Computer: Any system operated by Linux or Unix Operating system: Linux Classification: 7.7 External routines: We provide wrappers for FFTW [1], Intel MKL library [2] FFT routine, and Numerical recipes [3] FFT, random number generator, and eigenvalue solver routines, SPRNG [4] random number generator, Mersenne Twister [5] random number generator, space filling curve routine. Catalogue identifier of previous version: ADXP_v1_0 Journal reference of previous version: Comput. Phys. Comm. 174 (2006) 560 Does the new version supersede the previous version?: Yes Nature of problem: Structural, thermodynamic, and dynamical properties of fluids and solids from microscopic scales to mesoscopic scales. Solution method: Molecular dynamics simulation in NVE, NVT, and NPT ensemble, Langevin dynamics simulation, dissipative particle dynamics simulation. Reasons for new version: First, object-oriented programming has been used, which is known to be open for extension and closed for modification. It is also known to be better for maintenance. Second, version 1.0 was based on atom decomposition and domain decomposition scheme [6] for parallelization. However, atom decomposition is not popular due to its poor scalability. On the other hand, domain decomposition scheme is better for scalability. It still has a limitation in utilizing a large number of cores on recent petascale computers due to the requirement that the domain size is larger than the potential cutoff distance. To go beyond such a limitation, a hierarchical parallelization scheme has been adopted in this new version and implemented using MPI [7] and OPENMP [8]. Summary of revisions: (1) Object-oriented programming has been used. (2) A hierarchical parallelization scheme has been adopted. (3) SPME routine has been fully parallelized with parallel 3D FFT using volumetric decomposition scheme [9]. K.J.O. thanks Mr. Seung Min Lee for useful discussion on programming and debugging. Running time: Running time depends on system size and methods used. For test system containing a protein (PDB id: 5DHFR) with CHARMM22 force field [10] and 7023 TIP3P [11] waters in simulation box having dimension 62.23 Å×62.23 Å×62.23 Å, the benchmark results are given in Fig. 1. Here the potential cutoff distance was set to 12 Å and the switching function was applied from 10 Å for the force calculation in real space. For the SPME [12] calculation, K, K, and K were set to 64 and the interpolation order was set to 4. To do the fast Fourier transform, we used Intel MKL library. All bonds including hydrogen atoms were constrained using SHAKE/RATTLE algorithms [13,14]. The code was compiled using Intel compiler version 11.1 and mvapich2 version 1.5. Fig. 2 shows performance gains from using CUDA-enabled version [15] of mm_par for 5DHFR simulation in water on Intel Core2Quad 2.83 GHz and GeForce GTX 580. Even though mm_par2.0 is not ported yet for GPU, its performance data would be useful to expect mm_par2.0 performance on GPU. Timing results for 1000 MD steps. 1, 2, 4, and 8 in the figure mean the number of OPENMP threads. Timing results for 1000 MD steps from double precision simulation on CPU, single precision simulation on GPU, and double precision simulation on GPU.

Enabling Big Geoscience Data Analytics with a Cloud-Based, MapReduce-Enabled and Service-Oriented Workflow Framework

PubMed Central

Li, Zhenlong; Yang, Chaowei; Jin, Baoxuan; Yu, Manzhu; Liu, Kai; Sun, Min; Zhan, Matthew

2015-01-01

Geoscience observations and model simulations are generating vast amounts of multi-dimensional data. Effectively analyzing these data are essential for geoscience studies. However, the tasks are challenging for geoscientists because processing the massive amount of data is both computing and data intensive in that data analytics requires complex procedures and multiple tools. To tackle these challenges, a scientific workflow framework is proposed for big geoscience data analytics. In this framework techniques are proposed by leveraging cloud computing, MapReduce, and Service Oriented Architecture (SOA). Specifically, HBase is adopted for storing and managing big geoscience data across distributed computers. MapReduce-based algorithm framework is developed to support parallel processing of geoscience data. And service-oriented workflow architecture is built for supporting on-demand complex data analytics in the cloud environment. A proof-of-concept prototype tests the performance of the framework. Results show that this innovative framework significantly improves the efficiency of big geoscience data analytics by reducing the data processing time as well as simplifying data analytical procedures for geoscientists. PMID:25742012

Enabling big geoscience data analytics with a cloud-based, MapReduce-enabled and service-oriented workflow framework.

PubMed

Li, Zhenlong; Yang, Chaowei; Jin, Baoxuan; Yu, Manzhu; Liu, Kai; Sun, Min; Zhan, Matthew

2015-01-01

Geoscience observations and model simulations are generating vast amounts of multi-dimensional data. Effectively analyzing these data are essential for geoscience studies. However, the tasks are challenging for geoscientists because processing the massive amount of data is both computing and data intensive in that data analytics requires complex procedures and multiple tools. To tackle these challenges, a scientific workflow framework is proposed for big geoscience data analytics. In this framework techniques are proposed by leveraging cloud computing, MapReduce, and Service Oriented Architecture (SOA). Specifically, HBase is adopted for storing and managing big geoscience data across distributed computers. MapReduce-based algorithm framework is developed to support parallel processing of geoscience data. And service-oriented workflow architecture is built for supporting on-demand complex data analytics in the cloud environment. A proof-of-concept prototype tests the performance of the framework. Results show that this innovative framework significantly improves the efficiency of big geoscience data analytics by reducing the data processing time as well as simplifying data analytical procedures for geoscientists.

Genten: Software for Generalized Tensor Decompositions v. 1.0.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phipps, Eric T.; Kolda, Tamara G.; Dunlavy, Daniel

Tensors, or multidimensional arrays, are a powerful mathematical means of describing multiway data. This software provides computational means for decomposing or approximating a given tensor in terms of smaller tensors of lower dimension, focusing on decomposition of large, sparse tensors. These techniques have applications in many scientific areas, including signal processing, linear algebra, computer vision, numerical analysis, data mining, graph analysis, neuroscience and more. The software is designed to take advantage of parallelism present emerging computer architectures such has multi-core CPUs, many-core accelerators such as the Intel Xeon Phi, and computation-oriented GPUs to enable efficient processing of large tensors.

ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data.

PubMed

Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S; Windus, Theresa L; Dick-Perez, Marilu

2017-03-27

A newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides, important for metal extraction chemistry, are parametrized using ParFit. ParFit is in an open source program available for free on GitHub ( https://github.com/fzahari/ParFit ).

Programs as Polypeptides.

PubMed

Williams, Lance R

2016-01-01

Object-oriented combinator chemistry (OOCC) is an artificial chemistry with composition devices borrowed from object-oriented and functional programming languages. Actors in OOCC are embedded in space and subject to diffusion; since they are neither created nor destroyed, their mass is conserved. Actors use programs constructed from combinators to asynchronously update their own states and the states of other actors in their neighborhoods. The fact that programs and combinators are themselves reified as actors makes it possible to build programs that build programs from combinators of a few primitive types using asynchronous spatial processes that resemble chemistry as much as computation. To demonstrate this, OOCC is used to define a parallel, asynchronous, spatially distributed self-replicating system modeled in part on the living cell. Since interactions among its parts result in the construction of more of these same parts, the system is strongly constructive. The system's high normalized complexity is contrasted with that of a simple composome.

Science Objectives for a Soft X-ray Mission

NASA Astrophysics Data System (ADS)

Sibeck, D. G.; Connor, H. K.; Collier, M. R.; Collado-Vega, Y. M.; Walsh, B.

2016-12-01

When high charge state solar wind ions exchange electrons with exospheric neutrals, soft X-rays are emitted. In conjunction with flight- proven wide field-of-view soft X-ray imagers employing lobster-eye optics, recent simulations demonstrate the feasibility of imaging magnetospheric density structures such as the bow shock, magnetopause, and cusps. This presentation examines the Heliospheric scientific objectives that such imagers can address. Principal amongst these is the nature of reconnection at the dayside magnetopause: steady or transient, widespread or localized, component or antiparallel as a function of solar wind conditions. However, amongst many other objectives, soft X-ray imagers can provide crucial information concerning the structure of the bow shock as a function of solar wind Mach number and IMF orientation, the presence or absence of a depletion layer, the occurrence of Kelvin-Helmholtz or pressure-pulse driven magnetopause boundary waves, and the effects of radial IMF orientations and the foreshock upon bow shock and magnetopause location.

Recognition of the Multi Specularity Objects using the Eigen-Window,

DTIC Science & Technology

1996-02-29

analysis to each eigen-window [21]. The basic idea is that, even if some of the windows are occluded, the remaining windows are still effective and can...K.Ikeuchi, “The Machanical Manipulation of Randomly Oriented Parts”, Scientific American, Vol.251, No.2, pp.100-111, 1984. [5] S.A.Hutchinson and A.C.Kak

Xyce parallel electronic simulator users guide, version 6.1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R; Mei, Ting; Russo, Thomas V.

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas; Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). This includes support for most popular parallel and serial computers; A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to developmore » new types of analysis without requiring the implementation of analysis-specific device models; Device models that are specifically tailored to meet Sandia's needs, including some radiationaware devices (for Sandia users only); and Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase-a message passing parallel implementation-which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows.« less

Xyce parallel electronic simulator users' guide, Version 6.0.1.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R; Mei, Ting; Russo, Thomas V.

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to developmore » new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandias needs, including some radiationaware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase a message passing parallel implementation which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows.« less

Xyce parallel electronic simulator users guide, version 6.0.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R; Mei, Ting; Russo, Thomas V.

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to developmore » new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandias needs, including some radiationaware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase a message passing parallel implementation which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows.« less

Parallel object-oriented data mining system

DOEpatents

Kamath, Chandrika; Cantu-Paz, Erick

2004-01-06

A data mining system uncovers patterns, associations, anomalies and other statistically significant structures in data. Data files are read and displayed. Objects in the data files are identified. Relevant features for the objects are extracted. Patterns among the objects are recognized based upon the features. Data from the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) sky survey was used to search for bent doubles. This test was conducted on data from the Very Large Array in New Mexico which seeks to locate a special type of quasar (radio-emitting stellar object) called bent doubles. The FIRST survey has generated more than 32,000 images of the sky to date. Each image is 7.1 megabytes, yielding more than 100 gigabytes of image data in the entire data set.

The BLAZE language: A parallel language for scientific programming

NASA Technical Reports Server (NTRS)

Mehrotra, P.; Vanrosendale, J.

1985-01-01

A Pascal-like scientific programming language, Blaze, is described. Blaze contains array arithmetic, forall loops, and APL-style accumulation operators, which allow natural expression of fine grained parallelism. It also employs an applicative or functional procedure invocation mechanism, which makes it easy for compilers to extract coarse grained parallelism using machine specific program restructuring. Thus Blaze should allow one to achieve highly parallel execution on multiprocessor architectures, while still providing the user with onceptually sequential control flow. A central goal in the design of Blaze is portability across a broad range of parallel architectures. The multiple levels of parallelism present in Blaze code, in principle, allow a compiler to extract the types of parallelism appropriate for the given architecture while neglecting the remainder. The features of Blaze are described and shows how this language would be used in typical scientific programming.

Possibilities of the Integration of the Method of the Ecologically Oriented Independent Scientific Research in the Study Process

NASA Astrophysics Data System (ADS)

Grizans, Jurijs; Vanags, Janis

2010-01-01

The aim of this paper is to analyse possibilities of the integration of the method of the ecologically oriented independent scientific research in the study process. In order to achieve the set aim, the following scientific research methods were used: analysis of the conceptual guidelines for the development of environmentally oriented entrepreneurship, interpretation of the experts' evaluation of the ecologically oriented management, analysis of the results of the students' ecologically oriented independent scientific research, as well as monographic and logically constructive methods. The results of the study give an opportunity to make conclusions and to develop conceptual recommendations on how to introduce future economics and business professionals with the theoretical and practical aspects of ecologically oriented management during the study process.

The BLAZE language - A parallel language for scientific programming

NASA Technical Reports Server (NTRS)

Mehrotra, Piyush; Van Rosendale, John

1987-01-01

A Pascal-like scientific programming language, BLAZE, is described. BLAZE contains array arithmetic, forall loops, and APL-style accumulation operators, which allow natural expression of fine grained parallelism. It also employs an applicative or functional procedure invocation mechanism, which makes it easy for compilers to extract coarse grained parallelism using machine specific program restructuring. Thus BLAZE should allow one to achieve highly parallel execution on multiprocessor architectures, while still providing the user with conceptually sequential control flow. A central goal in the design of BLAZE is portability across a broad range of parallel architectures. The multiple levels of parallelism present in BLAZE code, in principle, allow a compiler to extract the types of parallelism appropriate for the given architecture while neglecting the remainder. The features of BLAZE are described and it is shown how this language would be used in typical scientific programming.

Developing Instruments Concerning Scientific Epistemic Beliefs and Goal Orientations in Learning Science: A Validation Study

ERIC Educational Resources Information Center

Lin, Tzung-Jin; Tsai, Chin-Chung

2017-01-01

The purpose of this study was to develop and validate two survey instruments to evaluate high school students' scientific epistemic beliefs and goal orientations in learning science. The initial relationships between the sampled students' scientific epistemic beliefs and goal orientations in learning science were also investigated. A final valid…

The Relations between Scientific Epistemological Beliefs and Goal Orientations of Pre-Service Teachers

ERIC Educational Resources Information Center

Kaya, Gamze Inan

2017-01-01

The purpose of this study was to investigate the relations between pre-service teachers' scientific epistemological beliefs and goal orientations in 2X2 framework. Scientific epistemological beliefs are domain-specific views of people about nature and acquisition of scientific knowledge, how scientific knowledge is produced, how reliable and valid…

Planning and Resource Management in an Intelligent Automated Power Management System

NASA Technical Reports Server (NTRS)

Morris, Robert A.

1991-01-01

Power system management is a process of guiding a power system towards the objective of continuous supply of electrical power to a set of loads. Spacecraft power system management requires planning and scheduling, since electrical power is a scarce resource in space. The automation of power system management for future spacecraft has been recognized as an important R&D goal. Several automation technologies have emerged including the use of expert systems for automating human problem solving capabilities such as rule based expert system for fault diagnosis and load scheduling. It is questionable whether current generation expert system technology is applicable for power system management in space. The objective of the ADEPTS (ADvanced Electrical Power management Techniques for Space systems) is to study new techniques for power management automation. These techniques involve integrating current expert system technology with that of parallel and distributed computing, as well as a distributed, object-oriented approach to software design. The focus of the current study is the integration of new procedures for automatically planning and scheduling loads with procedures for performing fault diagnosis and control. The objective is the concurrent execution of both sets of tasks on separate transputer processors, thus adding parallelism to the overall management process.

CVXPY: A Python-Embedded Modeling Language for Convex Optimization.

PubMed

Diamond, Steven; Boyd, Stephen

2016-04-01

CVXPY is a domain-specific language for convex optimization embedded in Python. It allows the user to express convex optimization problems in a natural syntax that follows the math, rather than in the restrictive standard form required by solvers. CVXPY makes it easy to combine convex optimization with high-level features of Python such as parallelism and object-oriented design. CVXPY is available at http://www.cvxpy.org/ under the GPL license, along with documentation and examples.

Identification of cultivated land using remote sensing images based on object-oriented artificial bee colony algorithm

NASA Astrophysics Data System (ADS)

Li, Nan; Zhu, Xiufang

2017-04-01

Cultivated land resources is the key to ensure food security. Timely and accurate access to cultivated land information is conducive to a scientific planning of food production and management policies. The GaoFen 1 (GF-1) images have high spatial resolution and abundant texture information and thus can be used to identify fragmentized cultivated land. In this paper, an object-oriented artificial bee colony algorithm was proposed for extracting cultivated land from GF-1 images. Firstly, the GF-1 image was segmented by eCognition software and some samples from the segments were manually identified into 2 types (cultivated land and non-cultivated land). Secondly, the artificial bee colony (ABC) algorithm was used to search for classification rules based on the spectral and texture information extracted from the image objects. Finally, the extracted classification rules were used to identify the cultivated land area on the image. The experiment was carried out in Hongze area, Jiangsu Province using wide field-of-view sensor on the GF-1 satellite image. The total precision of classification result was 94.95%, and the precision of cultivated land was 92.85%. The results show that the object-oriented ABC algorithm can overcome the defect of insufficient spectral information in GF-1 images and obtain high precision in cultivated identification.

Tuning HDF5 for Lustre File Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howison, Mark; Koziol, Quincey; Knaak, David

2010-09-24

HDF5 is a cross-platform parallel I/O library that is used by a wide variety of HPC applications for the flexibility of its hierarchical object-database representation of scientific data. We describe our recent work to optimize the performance of the HDF5 and MPI-IO libraries for the Lustre parallel file system. We selected three different HPC applications to represent the diverse range of I/O requirements, and measured their performance on three different systems to demonstrate the robustness of our optimizations across different file system configurations and to validate our optimization strategy. We demonstrate that the combined optimizations improve HDF5 parallel I/O performancemore » by up to 33 times in some cases running close to the achievable peak performance of the underlying file system and demonstrate scalable performance up to 40,960-way concurrency.« less

Development of an object-oriented finite element program: application to metal-forming and impact simulations

NASA Astrophysics Data System (ADS)

Pantale, O.; Caperaa, S.; Rakotomalala, R.

2004-07-01

During the last 50 years, the development of better numerical methods and more powerful computers has been a major enterprise for the scientific community. In the same time, the finite element method has become a widely used tool for researchers and engineers. Recent advances in computational software have made possible to solve more physical and complex problems such as coupled problems, nonlinearities, high strain and high-strain rate problems. In this field, an accurate analysis of large deformation inelastic problems occurring in metal-forming or impact simulations is extremely important as a consequence of high amount of plastic flow. In this presentation, the object-oriented implementation, using the C++ language, of an explicit finite element code called DynELA is presented. The object-oriented programming (OOP) leads to better-structured codes for the finite element method and facilitates the development, the maintainability and the expandability of such codes. The most significant advantage of OOP is in the modeling of complex physical systems such as deformation processing where the overall complex problem is partitioned in individual sub-problems based on physical, mathematical or geometric reasoning. We first focus on the advantages of OOP for the development of scientific programs. Specific aspects of OOP, such as the inheritance mechanism, the operators overload procedure or the use of template classes are detailed. Then we present the approach used for the development of our finite element code through the presentation of the kinematics, conservative and constitutive laws and their respective implementation in C++. Finally, the efficiency and accuracy of our finite element program are investigated using a number of benchmark tests relative to metal forming and impact simulations.

LibHalfSpace: A C++ object-oriented library to study deformation and stress in elastic half-spaces

NASA Astrophysics Data System (ADS)

Ferrari, Claudio; Bonafede, Maurizio; Belardinelli, Maria Elina

2016-11-01

The study of deformation processes in elastic half-spaces is widely employed for many purposes (e.g. didactic, scientific investigation of real processes, inversion of geodetic data, etc.). We present a coherent programming interface containing a set of tools designed to make easier and faster the study of processes in an elastic half-space. LibHalfSpace is presented in the form of an object-oriented library. A set of well known and frequently used source models (Mogi source, penny shaped horizontal crack, inflating spheroid, Okada rectangular dislocation, etc.) are implemented to describe the potential usage and the versatility of the library. The common interface given to library tools enables us to switch easily among the effects produced by different deformation sources that can be monitored at the free surface. Furthermore, the library also offers an interface which simplifies the creation of new source models exploiting the features of object-oriented programming (OOP). These source models can be built as distributions of rectangular boundary elements. In order to better explain how new models can be deployed some examples are included in the library.

[ECRIN (European clinical research infrastructures network), a pan-European infrastructure for clinical research].

PubMed

Demotes-Mainard, Jacques

2010-12-01

Clinical research plays a key role both in the development of innovative health products and in the optimisation of medical strategies, leading to evidence-based practice and healthcare cost containment. ECRIN is a distributed ESFRI-roadmap pan-European infrastructure designed to support multinational clinical research, making Europe a single area for clinical studies, taking advantage of its population size to access patients, and unlocking latent scientific providing services to multinational. Servicing of multinational trials started during the preparatory phase, and ECRIN has applied for ERIC status in 2011. In parallel, ECRIN has also proposed an FP7 integrating activity project to further develop, upgrade and expand the ECRIN infrastructure built up during the past FP6 and FP7 projects, facilitating an efficient organization of clinical research in Europe, with ECRIN developing generic tools and providing generic services for multinational studies, and supporting the construction of pan-European disease-oriented networks that will in turn act as ECRIN users. This organization will improve Europe's attractiveness for industry trials, boost its scientific competitiveness, and result in better healthcare for European citizens. The three medical areas supported in this project (rare diseases, medical devices, and nutrition) will serve as pilots for other biomedical research fields. By creating a single area for clinical research in Europe, this structure will contribute to the implementation of the Europe flagship initiative 2020 'Innovation Union', whose objectives include defragmentation of research and educational capacities, tackling the major societal challenges (starting with healthy aging), and removing barriers to bringing ideas to the market.

Application of construal level and value-belief norm theories to undergraduate decision-making on a wildlife socio-scientific issue

NASA Astrophysics Data System (ADS)

Sutter, A. McKinzie; Dauer, Jenny M.; Forbes, Cory T.

2018-06-01

One aim of science education is to develop scientific literacy for decision-making in daily life. Socio-scientific issues (SSI) and structured decision-making frameworks can help students reach these objectives. This research uses value belief norm (VBN) theory and construal level theory (CLT) to explore students' use of personal values in their decision-making processes and the relationship between abstract and concrete problematization and their decision-making. Using mixed methods, we conclude that the level of abstraction with which students problematise a prairie dog agricultural production and ecosystem preservation issue has a significant relationship to the values students used in the decision-making process. However, neither abstraction of the problem statement nor students' surveyed value orientations were significantly related to students' final decisions. These results may help inform teachers' understanding of students and their use of a structured-decision making tool in a classroom, and aid researchers in understanding if these tools help students remain objective in their analyses of complex SSIs.

Transformation of shock-compressed graphite to hexagonal diamond in nanoseconds

PubMed Central

Turneaure, Stefan J.; Sharma, Surinder M.; Volz, Travis J.; Winey, J. M.; Gupta, Yogendra M.

2017-01-01

The graphite-to-diamond transformation under shock compression has been of broad scientific interest since 1961. The formation of hexagonal diamond (HD) is of particular interest because it is expected to be harder than cubic diamond and due to its use in terrestrial sciences as a marker at meteorite impact sites. However, the formation of diamond having a fully hexagonal structure continues to be questioned and remains unresolved. Using real-time (nanosecond), in situ x-ray diffraction measurements, we show unequivocally that highly oriented pyrolytic graphite, shock-compressed along the c axis to 50 GPa, transforms to highly oriented elastically strained HD with the (100)HD plane parallel to the graphite basal plane. These findings contradict recent molecular dynamics simulation results for the shock-induced graphite-to-diamond transformation and provide a benchmark for future theoretical simulations. Additionally, our results show that an earlier report of HD forming only above 170 GPa for shocked pyrolytic graphite may lead to incorrect interpretations of meteorite impact events. PMID:29098183

Transformation of shock-compressed graphite to hexagonal diamond in nanoseconds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turneaure, Stefan J.; Sharma, Surinder M.; Volz, Travis J.

The graphite-to-diamond transformation under shock compression has been of broad scientific interest since 1961. The formation of hexagonal diamond (HD) is of particular interest because it is expected to be harder than cubic diamond and due to its use in terrestrial sciences as a marker at meteorite impact sites. However, the formation of diamond having a fully hexagonal structure continues to be questioned and remains unresolved. Using real-time (nanosecond), in situ x-ray diffraction measurements, we show unequivocally that highly oriented pyrolytic graphite, shock-compressed along the c axis to 50 GPa, transforms to highly oriented elastically strained HD with the (100)HDmore » plane parallel to the graphite basal plane. These findings contradict recent molecular dynamics simulation results for the shock-induced graphite-to-diamond transformation and provide a benchmark for future theoretical simulations. Additionally, our results show that an earlier report of HD forming only above 170 GPa for shocked pyrolytic graphite may lead to incorrect interpretations of meteorite impact events.« less

Transformation of shock-compressed graphite to hexagonal diamond in nanoseconds

DOE PAGES

Turneaure, Stefan J.; Sharma, Surinder M.; Volz, Travis J.; ...

2017-10-27

The graphite-to-diamond transformation under shock compression has been of broad scientific interest since 1961. The formation of hexagonal diamond (HD) is of particular interest because it is expected to be harder than cubic diamond and due to its use in terrestrial sciences as a marker at meteorite impact sites. However, the formation of diamond having a fully hexagonal structure continues to be questioned and remains unresolved. Using real-time (nanosecond), in situ x-ray diffraction measurements, we show unequivocally that highly oriented pyrolytic graphite, shock-compressed along the c axis to 50 GPa, transforms to highly oriented elastically strained HD with the (100)HDmore » plane parallel to the graphite basal plane. These findings contradict recent molecular dynamics simulation results for the shock-induced graphite-to-diamond transformation and provide a benchmark for future theoretical simulations. Additionally, our results show that an earlier report of HD forming only above 170 GPa for shocked pyrolytic graphite may lead to incorrect interpretations of meteorite impact events.« less

Xyce Parallel Electronic Simulator Users' Guide Version 6.8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R.; Aadithya, Karthik Venkatraman; Mei, Ting

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been de- signed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel com- puting platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows onemore » to develop new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandia's needs, including some radiation- aware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase$-$ a message passing parallel implementation $-$ which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows.« less

Paradise: A Parallel Information System for EOSDIS

NASA Technical Reports Server (NTRS)

DeWitt, David

1996-01-01

The Paradise project was begun-in 1993 in order to explore the application of the parallel and object-oriented database system technology developed as a part of the Gamma, Exodus. and Shore projects to the design and development of a scaleable, geo-spatial database system for storing both massive spatial and satellite image data sets. Paradise is based on an object-relational data model. In addition to the standard attribute types such as integers, floats, strings and time, Paradise also provides a set of and multimedia data types, designed to facilitate the storage and querying of complex spatial and multimedia data sets. An individual tuple can contain any combination of this rich set of data types. For example, in the EOSDIS context, a tuple might mix terrain and map data for an area along with the latest satellite weather photo of the area. The use of a geo-spatial metaphor simplifies the task of fusing disparate forms of data from multiple data sources including text, image, map, and video data sets.

Parallel computing works

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

An account of the Caltech Concurrent Computation Program (C{sup 3}P), a five year project that focused on answering the question: Can parallel computers be used to do large-scale scientific computations '' As the title indicates, the question is answered in the affirmative, by implementing numerous scientific applications on real parallel computers and doing computations that produced new scientific results. In the process of doing so, C{sup 3}P helped design and build several new computers, designed and implemented basic system software, developed algorithms for frequently used mathematical computations on massively parallel machines, devised performance models and measured the performance of manymore » computers, and created a high performance computing facility based exclusively on parallel computers. While the initial focus of C{sup 3}P was the hypercube architecture developed by C. Seitz, many of the methods developed and lessons learned have been applied successfully on other massively parallel architectures.« less

Revisiting elastic anisotropy of biotite gneiss from the Outokumpu scientific drill hole based on new texture measurements and texture-based velocity calculations

NASA Astrophysics Data System (ADS)

Wenk, H.-R.; Vasin, R. N.; Kern, H.; Matthies, S.; Vogel, S. C.; Ivankina, T. I.

2012-10-01

A sample of biotite gneiss from the Outokumpu deep drilling project in Finland was investigated by Kern et al. (2008) for crystal preferred orientation and elastic anisotropy. Considerable differences between measured acoustic velocities and velocities calculated on the basis of texture patterns were observed. Measured P-wave anisotropy was 15.1% versus a Voigt average yielding 7.9%. Here we investigate the same sample with different methods and using different averaging techniques. Analyzing time-of-flight neutron diffraction data from Dubna-SKAT and LANSCE-HIPPO diffractometers with the Rietveld technique, much stronger preferred orientation for biotite is determined, compared to conventional pole-figure analysis reported previously. The comparison reveals important differences: HIPPO has much better counting statistics but pole figure coverage is poor. SKAT has better angular resolution. Using the new preferred orientation data and applying a self-consistent averaging method that takes grain shapes into account, close agreement of calculated and measured P-wave velocities is observed (12.6%). This is further improved by adding 0.1 vol.% flat micropores parallel to the biotite platelets in the simulation (14.9%).

A system to evaluate the scientific quality of biological and restoration objectives using National Wildlife Refuge Comprehensive Conservation Plans as a case study

USGS Publications Warehouse

Schroeder, R.L.

2006-01-01

It is widely accepted that plans for restoration projects should contain specific, measurable, and science-based objectives to guide restoration efforts. The United States Fish and Wildlife Service (USFWS) is in the process of developing Comprehensive Conservation Plans (CCPs) for more than 500 units in the National Wildlife Refuge System (NWRS). These plans contain objectives for biological and ecosystem restoration efforts on the refuges. Based on USFWS policy, a system was developed to evaluate the scientific quality of such objectives based on three critical factors: (1) Is the objective specific, measurable, achievable, results-oriented, and time-fixed? (2) What is the extent of the rationale that explains the assumptions, logic, and reasoning for the objective? (3) How well was available science used in the development of the objective? The evaluation system scores each factor on a scale of 1 (poor) to 4 (excellent) according to detailed criteria. The biological and restoration objectives from CCPs published as of September 2004 (60 total) were evaluated. The overall average score for all biological and restoration objectives was 1.73. Average scores for each factor were: Factor 1-1.97; Factor 2-1.86; Factor 3-1.38. The overall scores increased from 1997 to 2004. Future restoration efforts may benefit by using this evaluation system during the process of plan development, to ensure that biological and restoration objectives are of the highest scientific quality possible prior to the implementation of restoration plans, and to allow for improved monitoring and adaptive management.

Values and Objectivity in Science: Value-Ladenness, Pluralism and the Epistemic Attitude

NASA Astrophysics Data System (ADS)

Carrier, Martin

2013-10-01

My intention is to cast light on the characteristics of epistemic or fundamental research (in contrast to application-oriented research). I contrast a Baconian notion of objectivity, expressing a correspondence of the views of scientists to the facts, with a pluralist notion, involving a critical debate between conflicting approaches. These conflicts include substantive hypotheses or theories but extend to values as well. I claim that a plurality of epistemic values serves to accomplish a non-Baconian form of objectivity that is apt to preserve most of the intuitions tied to the objectivity of science. For instance, pluralism is the only way to cope with the challenge of preference bias. Furthermore, the plurality of epistemic values cannot be substantially reduced by exploring the empirical success of scientific theories distinguished in light of particular such values. However, in addition to pluralism at the level of theories and value-commitments alike, scientific research is also characterized by a joint striving for consensus which I trace back to a shared epistemic attitude. This attitude manifests itself, e.g., in the willingness of scientists to subject their claims to empirical scrutiny and to respect rational argument. This shared epistemic attitude is embodied in rules adopted by the scientific community concerning general principles of dealing with knowledge claims. My contention is that pluralism and consensus formation can be brought into harmony by placing them at different levels of consideration: at the level of scientific reasoning and at the level of social conventions regarding how to deal with claims put forward within the scientific community.

A distributed component framework for science data product interoperability

NASA Technical Reports Server (NTRS)

Crichton, D.; Hughes, S.; Kelly, S.; Hardman, S.

2000-01-01

Correlation of science results from multi-disciplinary communities is a difficult task. Traditionally data from science missions is archived in proprietary data systems that are not interoperable. The Object Oriented Data Technology (OODT) task at the Jet Propulsion Laboratory is working on building a distributed product server as part of a distributed component framework to allow heterogeneous data systems to communicate and share scientific results.

Agent-Based Scientific Workflow Composition

NASA Astrophysics Data System (ADS)

Barker, A.; Mann, B.

2006-07-01

Agents are active autonomous entities that interact with one another to achieve their objectives. This paper addresses how these active agents are a natural fit to consume the passive Service Oriented Architecture which is found in Internet and Grid Systems, in order to compose, coordinate and execute e-Science experiments. A framework is introduced which allows an e-Science experiment to be described as a MultiAgent System.

CVXPY: A Python-Embedded Modeling Language for Convex Optimization

PubMed Central

Diamond, Steven; Boyd, Stephen

2016-01-01

CVXPY is a domain-specific language for convex optimization embedded in Python. It allows the user to express convex optimization problems in a natural syntax that follows the math, rather than in the restrictive standard form required by solvers. CVXPY makes it easy to combine convex optimization with high-level features of Python such as parallelism and object-oriented design. CVXPY is available at http://www.cvxpy.org/ under the GPL license, along with documentation and examples. PMID:27375369

Bringing science to medicine: an interview with Larry Weed, inventor of the problem-oriented medical record

PubMed Central

Wright, Adam; Sittig, Dean F; McGowan, Julie; Ash, Joan S; Weed, Lawrence L

2014-01-01

Larry Weed, MD is widely known as the father of the problem-oriented medical record and inventor of the now-ubiquitous SOAP (subjective/objective/assessment/plan) note, for developing an electronic health record system (Problem-Oriented Medical Information System, PROMIS), and for founding a company (since acquired), which developed problem-knowledge couplers. However, Dr Weed's vision for medicine goes far beyond software—over the course of his storied career, he has relentlessly sought to bring the scientific method to medical practice and, where necessary, to point out shortcomings in the system and advocate for change. In this oral history, Dr Weed describes, in his own words, the arcs of his long career and the work that remains to be done. PMID:24872343

Parallel algorithm for determining motion vectors in ice floe images by matching edge features

NASA Technical Reports Server (NTRS)

Manohar, M.; Ramapriyan, H. K.; Strong, J. P.

1988-01-01

A parallel algorithm is described to determine motion vectors of ice floes using time sequences of images of the Arctic ocean obtained from the Synthetic Aperture Radar (SAR) instrument flown on-board the SEASAT spacecraft. Researchers describe a parallel algorithm which is implemented on the MPP for locating corresponding objects based on their translationally and rotationally invariant features. The algorithm first approximates the edges in the images by polygons or sets of connected straight-line segments. Each such edge structure is then reduced to a seed point. Associated with each seed point are the descriptions (lengths, orientations and sequence numbers) of the lines constituting the corresponding edge structure. A parallel matching algorithm is used to match packed arrays of such descriptions to identify corresponding seed points in the two images. The matching algorithm is designed such that fragmentation and merging of ice floes are taken into account by accepting partial matches. The technique has been demonstrated to work on synthetic test patterns and real image pairs from SEASAT in times ranging from .5 to 0.7 seconds for 128 x 128 images.

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis :

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S.

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a user's manual for the Dakota software and provides capability overviews and procedures for software execution, as well as a variety of example studies.« less

Task-oriented training with computer gaming in people with rheumatoid arthritisor osteoarthritis of the hand: study protocol of a randomized controlled pilot trial.

PubMed

Srikesavan, Cynthia Swarnalatha; Shay, Barbara; Robinson, David B; Szturm, Tony

2013-03-09

Significant restriction in the ability to participate in home, work and community life results from pain, fatigue, joint damage, stiffness and reduced joint range of motion and muscle strength in people with rheumatoid arthritis or osteoarthritis of the hand. With modest evidence on the therapeutic effectiveness of conventional hand exercises, a task-oriented training program via real life object manipulations has been developed for people with arthritis. An innovative, computer-based gaming platform that allows a broad range of common objects to be seamlessly transformed into therapeutic input devices through instrumentation with a motion-sense mouse has also been designed. Personalized objects are selected to target specific training goals such as graded finger mobility, strength, endurance or fine/gross dexterous functions. The movements and object manipulation tasks that replicate common situations in everyday living will then be used to control and play any computer game, making practice challenging and engaging. The ongoing study is a 6-week, single-center, parallel-group, equally allocated and assessor-blinded pilot randomized controlled trial. Thirty people with rheumatoid arthritis or osteoarthritis affecting the hand will be randomized to receive either conventional hand exercises or the task-oriented training. The purpose is to determine a preliminary estimation of therapeutic effectiveness and feasibility of the task-oriented training program. Performance based and self-reported hand function, and exercise compliance are the study outcomes. Changes in outcomes (pre to post intervention) within each group will be assessed by paired Student t test or Wilcoxon signed-rank test and between groups (control versus experimental) post intervention using unpaired Student t test or Mann-Whitney U test. The study findings will inform decisions on the feasibility, safety and completion rate and will also provide preliminary data on the treatment effects of the task-oriented training compared with conventional hand exercises in people with rheumatoid arthritis or osteoarthritis of the hand. ClinicalTrials.gov: NCT01635582.

Big data analytics workflow management for eScience

NASA Astrophysics Data System (ADS)

Fiore, Sandro; D'Anca, Alessandro; Palazzo, Cosimo; Elia, Donatello; Mariello, Andrea; Nassisi, Paola; Aloisio, Giovanni

2015-04-01

In many domains such as climate and astrophysics, scientific data is often n-dimensional and requires tools that support specialized data types and primitives if it is to be properly stored, accessed, analysed and visualized. Currently, scientific data analytics relies on domain-specific software and libraries providing a huge set of operators and functionalities. However, most of these software fail at large scale since they: (i) are desktop based, rely on local computing capabilities and need the data locally; (ii) cannot benefit from available multicore/parallel machines since they are based on sequential codes; (iii) do not provide declarative languages to express scientific data analysis tasks, and (iv) do not provide newer or more scalable storage models to better support the data multidimensionality. Additionally, most of them: (v) are domain-specific, which also means they support a limited set of data formats, and (vi) do not provide a workflow support, to enable the construction, execution and monitoring of more complex "experiments". The Ophidia project aims at facing most of the challenges highlighted above by providing a big data analytics framework for eScience. Ophidia provides several parallel operators to manipulate large datasets. Some relevant examples include: (i) data sub-setting (slicing and dicing), (ii) data aggregation, (iii) array-based primitives (the same operator applies to all the implemented UDF extensions), (iv) data cube duplication, (v) data cube pivoting, (vi) NetCDF-import and export. Metadata operators are available too. Additionally, the Ophidia framework provides array-based primitives to perform data sub-setting, data aggregation (i.e. max, min, avg), array concatenation, algebraic expressions and predicate evaluation on large arrays of scientific data. Bit-oriented plugins have also been implemented to manage binary data cubes. Defining processing chains and workflows with tens, hundreds of data analytics operators is the real challenge in many practical scientific use cases. This talk will specifically address the main needs, requirements and challenges regarding data analytics workflow management applied to large scientific datasets. Three real use cases concerning analytics workflows for sea situational awareness, fire danger prevention, climate change and biodiversity will be discussed in detail.

Using Coarrays to Parallelize Legacy Fortran Applications: Strategy and Case Study

DOE PAGES

Radhakrishnan, Hari; Rouson, Damian W. I.; Morris, Karla; ...

2015-01-01

This paper summarizes a strategy for parallelizing a legacy Fortran 77 program using the object-oriented (OO) and coarray features that entered Fortran in the 2003 and 2008 standards, respectively. OO programming (OOP) facilitates the construction of an extensible suite of model-verification and performance tests that drive the development. Coarray parallel programming facilitates a rapid evolution from a serial application to a parallel application capable of running on multicore processors and many-core accelerators in shared and distributed memory. We delineate 17 code modernization steps used to refactor and parallelize the program and study the resulting performance. Our initial studies were donemore » using the Intel Fortran compiler on a 32-core shared memory server. Scaling behavior was very poor, and profile analysis using TAU showed that the bottleneck in the performance was due to our implementation of a collective, sequential summation procedure. We were able to improve the scalability and achieve nearly linear speedup by replacing the sequential summation with a parallel, binary tree algorithm. We also tested the Cray compiler, which provides its own collective summation procedure. Intel provides no collective reductions. With Cray, the program shows linear speedup even in distributed-memory execution. We anticipate similar results with other compilers once they support the new collective procedures proposed for Fortran 2015.« less

PETSc Users Manual Revision 3.3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balay, S.; Brown, J.; Buschelman, K.

This manual describes the use of PETSc for the numerical solution of partial differential equations and related problems on high-performance computers. The Portable, Extensible Toolkit for Scientific Computation (PETSc) is a suite of data structures and routines that provide the building blocks for the implementation of large-scale application codes on parallel (and serial) computers. PETSc uses the MPI standard for all message-passing communication. PETSc includes an expanding suite of parallel linear, nonlinear equation solvers and time integrators that may be used in application codes written in Fortran, C, C++, Python, and MATLAB (sequential). PETSc provides many of the mechanisms neededmore » within parallel application codes, such as parallel matrix and vector assembly routines. The library is organized hierarchically, enabling users to employ the level of abstraction that is most appropriate for a particular problem. By using techniques of object-oriented programming, PETSc provides enormous flexibility for users. PETSc is a sophisticated set of software tools; as such, for some users it initially has a much steeper learning curve than a simple subroutine library. In particular, for individuals without some computer science background, experience programming in C, C++ or Fortran and experience using a debugger such as gdb or dbx, it may require a significant amount of time to take full advantage of the features that enable efficient software use. However, the power of the PETSc design and the algorithms it incorporates may make the efficient implementation of many application codes simpler than “rolling them” yourself; For many tasks a package such as MATLAB is often the best tool; PETSc is not intended for the classes of problems for which effective MATLAB code can be written. PETSc also has a MATLAB interface, so portions of your code can be written in MATLAB to “try out” the PETSc solvers. The resulting code will not be scalable however because currently MATLAB is inherently not scalable; and PETSc should not be used to attempt to provide a “parallel linear solver” in an otherwise sequential code. Certainly all parts of a previously sequential code need not be parallelized but the matrix generation portion must be parallelized to expect any kind of reasonable performance. Do not expect to generate your matrix sequentially and then “use PETSc” to solve the linear system in parallel. Since PETSc is under continued development, small changes in usage and calling sequences of routines will occur. PETSc is supported; see the web site http://www.mcs.anl.gov/petsc for information on contacting support. A http://www.mcs.anl.gov/petsc/publications may be found a list of publications and web sites that feature work involving PETSc. We welcome any reports of corrections for this document.« less

PETSc Users Manual Revision 3.4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balay, S.; Brown, J.; Buschelman, K.

This manual describes the use of PETSc for the numerical solution of partial differential equations and related problems on high-performance computers. The Portable, Extensible Toolkit for Scientific Computation (PETSc) is a suite of data structures and routines that provide the building blocks for the implementation of large-scale application codes on parallel (and serial) computers. PETSc uses the MPI standard for all message-passing communication. PETSc includes an expanding suite of parallel linear, nonlinear equation solvers and time integrators that may be used in application codes written in Fortran, C, C++, Python, and MATLAB (sequential). PETSc provides many of the mechanisms neededmore » within parallel application codes, such as parallel matrix and vector assembly routines. The library is organized hierarchically, enabling users to employ the level of abstraction that is most appropriate for a particular problem. By using techniques of object-oriented programming, PETSc provides enormous flexibility for users. PETSc is a sophisticated set of software tools; as such, for some users it initially has a much steeper learning curve than a simple subroutine library. In particular, for individuals without some computer science background, experience programming in C, C++ or Fortran and experience using a debugger such as gdb or dbx, it may require a significant amount of time to take full advantage of the features that enable efficient software use. However, the power of the PETSc design and the algorithms it incorporates may make the efficient implementation of many application codes simpler than “rolling them” yourself; For many tasks a package such as MATLAB is often the best tool; PETSc is not intended for the classes of problems for which effective MATLAB code can be written. PETSc also has a MATLAB interface, so portions of your code can be written in MATLAB to “try out” the PETSc solvers. The resulting code will not be scalable however because currently MATLAB is inherently not scalable; and PETSc should not be used to attempt to provide a “parallel linear solver” in an otherwise sequential code. Certainly all parts of a previously sequential code need not be parallelized but the matrix generation portion must be parallelized to expect any kind of reasonable performance. Do not expect to generate your matrix sequentially and then “use PETSc” to solve the linear system in parallel. Since PETSc is under continued development, small changes in usage and calling sequences of routines will occur. PETSc is supported; see the web site http://www.mcs.anl.gov/petsc for information on contacting support. A http://www.mcs.anl.gov/petsc/publications may be found a list of publications and web sites that feature work involving PETSc. We welcome any reports of corrections for this document.« less

PETSc Users Manual Revision 3.5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balay, S.; Abhyankar, S.; Adams, M.

This manual describes the use of PETSc for the numerical solution of partial differential equations and related problems on high-performance computers. The Portable, Extensible Toolkit for Scientific Computation (PETSc) is a suite of data structures and routines that provide the building blocks for the implementation of large-scale application codes on parallel (and serial) computers. PETSc uses the MPI standard for all message-passing communication. PETSc includes an expanding suite of parallel linear, nonlinear equation solvers and time integrators that may be used in application codes written in Fortran, C, C++, Python, and MATLAB (sequential). PETSc provides many of the mechanisms neededmore » within parallel application codes, such as parallel matrix and vector assembly routines. The library is organized hierarchically, enabling users to employ the level of abstraction that is most appropriate for a particular problem. By using techniques of object-oriented programming, PETSc provides enormous flexibility for users. PETSc is a sophisticated set of software tools; as such, for some users it initially has a much steeper learning curve than a simple subroutine library. In particular, for individuals without some computer science background, experience programming in C, C++ or Fortran and experience using a debugger such as gdb or dbx, it may require a significant amount of time to take full advantage of the features that enable efficient software use. However, the power of the PETSc design and the algorithms it incorporates may make the efficient implementation of many application codes simpler than “rolling them” yourself. ;For many tasks a package such as MATLAB is often the best tool; PETSc is not intended for the classes of problems for which effective MATLAB code can be written. PETSc also has a MATLAB interface, so portions of your code can be written in MATLAB to “try out” the PETSc solvers. The resulting code will not be scalable however because currently MATLAB is inherently not scalable; and PETSc should not be used to attempt to provide a “parallel linear solver” in an otherwise sequential code. Certainly all parts of a previously sequential code need not be parallelized but the matrix generation portion must be parallelized to expect any kind of reasonable performance. Do not expect to generate your matrix sequentially and then “use PETSc” to solve the linear system in parallel. Since PETSc is under continued development, small changes in usage and calling sequences of routines will occur. PETSc is supported; see the web site http://www.mcs.anl.gov/petsc for information on contacting support. A http://www.mcs.anl.gov/petsc/publications may be found a list of publications and web sites that feature work involving PETSc. We welcome any reports of corrections for this document.« less

Supporting 64-bit global indices in Epetra and other Trilinos packages :

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jhurani, Chetan; Austin, Travis M.; Heroux, Michael Allen

The Trilinos Project is an effort to facilitate the design, development, integration and ongoing support of mathematical software libraries within an object-oriented framework. It is intended for large-scale, complex multiphysics engineering and scientific applications [2, 4, 3]. Epetra is one of its basic packages. It provides serial and parallel linear algebra capabilities. Before Trilinos version 11.0, released in 2012, Epetra used the C++ int data-type for storing global and local indices for degrees of freedom (DOFs). Since int is typically 32-bit, this limited the largest problem size to be smaller than approximately two billion DOFs. This was true even ifmore » a distributed memory machine could handle larger problems. We have added optional support for C++ long long data-type, which is at least 64-bit wide, for global indices. To save memory, maintain the speed of memory-bound operations, and reduce further changes to the code, the local indices are still 32-bit. We document the changes required to achieve this feature and how the new functionality can be used. We also report on the lessons learned in modifying a mature and popular package from various perspectives design goals, backward compatibility, engineering decisions, C++ language features, effects on existing users and other packages, and build integration.« less

Real-Time MENTAT programming language and architecture

NASA Technical Reports Server (NTRS)

Grimshaw, Andrew S.; Silberman, Ami; Liu, Jane W. S.

1989-01-01

Real-time MENTAT, a programming environment designed to simplify the task of programming real-time applications in distributed and parallel environments, is described. It is based on the same data-driven computation model and object-oriented programming paradigm as MENTAT. It provides an easy-to-use mechanism to exploit parallelism, language constructs for the expression and enforcement of timing constraints, and run-time support for scheduling and exciting real-time programs. The real-time MENTAT programming language is an extended C++. The extensions are added to facilitate automatic detection of data flow and generation of data flow graphs, to express the timing constraints of individual granules of computation, and to provide scheduling directives for the runtime system. A high-level view of the real-time MENTAT system architecture and programming language constructs is provided.

Polarization-resolved second-harmonic-generation imaging of photoaged dermal collagen fiber

NASA Astrophysics Data System (ADS)

Yasui, Takeshi; Takahashi, Yu; Araki, Tsutomu

2009-02-01

Polarization-resolved second-harmonic-generation (SHG) microscopy is useful for assessment of collagen fiber orientation in tissues. In this paper, we investigated the relation between wrinkle direction and collagen orientation in ultraviolet-B-exposed (UVB-exposed) skin using polarization-resolved SHG microscopy. A polarization anisotropic image of the SHG light indicated that wrinkle direction in UVB-exposed skin is predominantly parallel to the orientation of dermal collagen fibers whereas no-UVB-exposed skin was dominated by collagen orientation parallel to the meridian line of body. The method proposed has the potential to become a powerful non-invasive tool for assessment of cutaneous photoaging.

The Validation by Measurement Theory of Proposed Object-Oriented Software Metrics

NASA Technical Reports Server (NTRS)

Neal, Ralph D.

1996-01-01

Moving software development into the engineering arena requires controllability, and to control a process, it must be measurable. Measuring the process does no good if the product is not also measured, i.e., being the best at producing an inferior product does not define a quality process. Also, not every number extracted from software development is a valid measurement. A valid measurement only results when we are able to verify that the number is representative of the attribute that we wish to measure. Many proposed software metrics are used by practitioners without these metrics ever having been validated, leading to costly but often useless calculations. Several researchers have bemoaned the lack of scientific precision in much of the published software measurement work and have called for validation of software metrics by measurement theory. This dissertation applies measurement theory to validate fifty proposed object-oriented software metrics.

An object-oriented programming system for the integration of internet-based bioinformatics resources.

PubMed

Beveridge, Allan

2006-01-01

The Internet consists of a vast inhomogeneous reservoir of data. Developing software that can integrate a wide variety of different data sources is a major challenge that must be addressed for the realisation of the full potential of the Internet as a scientific research tool. This article presents a semi-automated object-oriented programming system for integrating web-based resources. We demonstrate that the current Internet standards (HTML, CGI [common gateway interface], Java, etc.) can be exploited to develop a data retrieval system that scans existing web interfaces and then uses a set of rules to generate new Java code that can automatically retrieve data from the Web. The validity of the software has been demonstrated by testing it on several biological databases. We also examine the current limitations of the Internet and discuss the need for the development of universal standards for web-based data.

Lightweight Object Oriented Structure analysis: Tools for building Tools to Analyze Molecular Dynamics Simulations

PubMed Central

Romo, Tod D.; Leioatts, Nicholas; Grossfield, Alan

2014-01-01

LOOS (Lightweight Object-Oriented Structure-analysis) is a C++ library designed to facilitate making novel tools for analyzing molecular dynamics simulations by abstracting out the repetitive tasks, allowing developers to focus on the scientifically relevant part of the problem. LOOS supports input using the native file formats of most common biomolecular simulation packages, including CHARMM, NAMD, Amber, Tinker, and Gromacs. A dynamic atom selection language based on the C expression syntax is included and is easily accessible to the tool-writer. In addition, LOOS is bundled with over 120 pre-built tools, including suites of tools for analyzing simulation convergence, 3D histograms, and elastic network models. Through modern C++ design, LOOS is both simple to develop with (requiring knowledge of only 4 core classes and a few utility functions) and is easily extensible. A python interface to the core classes is also provided, further facilitating tool development. PMID:25327784

Lightweight object oriented structure analysis: tools for building tools to analyze molecular dynamics simulations.

PubMed

Romo, Tod D; Leioatts, Nicholas; Grossfield, Alan

2014-12-15

LOOS (Lightweight Object Oriented Structure-analysis) is a C++ library designed to facilitate making novel tools for analyzing molecular dynamics simulations by abstracting out the repetitive tasks, allowing developers to focus on the scientifically relevant part of the problem. LOOS supports input using the native file formats of most common biomolecular simulation packages, including CHARMM, NAMD, Amber, Tinker, and Gromacs. A dynamic atom selection language based on the C expression syntax is included and is easily accessible to the tool-writer. In addition, LOOS is bundled with over 140 prebuilt tools, including suites of tools for analyzing simulation convergence, three-dimensional histograms, and elastic network models. Through modern C++ design, LOOS is both simple to develop with (requiring knowledge of only four core classes and a few utility functions) and is easily extensible. A python interface to the core classes is also provided, further facilitating tool development. © 2014 Wiley Periodicals, Inc.

Flexible parallel implicit modelling of coupled thermal-hydraulic-mechanical processes in fractured rocks

NASA Astrophysics Data System (ADS)

Cacace, Mauro; Jacquey, Antoine B.

2017-09-01

Theory and numerical implementation describing groundwater flow and the transport of heat and solute mass in fully saturated fractured rocks with elasto-plastic mechanical feedbacks are developed. In our formulation, fractures are considered as being of lower dimension than the hosting deformable porous rock and we consider their hydraulic and mechanical apertures as scaling parameters to ensure continuous exchange of fluid mass and energy within the fracture-solid matrix system. The coupled system of equations is implemented in a new simulator code that makes use of a Galerkin finite-element technique. The code builds on a flexible, object-oriented numerical framework (MOOSE, Multiphysics Object Oriented Simulation Environment) which provides an extensive scalable parallel and implicit coupling to solve for the multiphysics problem. The governing equations of groundwater flow, heat and mass transport, and rock deformation are solved in a weak sense (either by classical Newton-Raphson or by free Jacobian inexact Newton-Krylow schemes) on an underlying unstructured mesh. Nonlinear feedbacks among the active processes are enforced by considering evolving fluid and rock properties depending on the thermo-hydro-mechanical state of the system and the local structure, i.e. degree of connectivity, of the fracture system. A suite of applications is presented to illustrate the flexibility and capability of the new simulator to address problems of increasing complexity and occurring at different spatial (from centimetres to tens of kilometres) and temporal scales (from minutes to hundreds of years).

Effects of microstructure banding on hydrogen assisted fatigue crack growth in X65 pipeline steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ronevich, Joseph A.; Somerday, Brian P.; San Marchi, Chris W.

Banded ferrite-pearlite X65 pipeline steel was tested in high pressure hydrogen gas to evaluate the effects of oriented pearlite on hydrogen assisted fatigue crack growth. Test specimens were oriented in the steel pipe such that cracks propagated either parallel or perpendicular to the banded pearlite. The ferrite-pearlite microstructure exhibited orientation dependent behavior in which fatigue crack growth rates were significantly lower for cracks oriented perpendicular to the banded pearlite compared to cracks oriented parallel to the bands. Thus the reduction of hydrogen assisted fatigue crack growth across the banded pearlite is attributed to a combination of crack-tip branching and impededmore » hydrogen diffusion across the banded pearlite.« less

Effects of microstructure banding on hydrogen assisted fatigue crack growth in X65 pipeline steels

DOE PAGES

Ronevich, Joseph A.; Somerday, Brian P.; San Marchi, Chris W.

2015-09-10

Banded ferrite-pearlite X65 pipeline steel was tested in high pressure hydrogen gas to evaluate the effects of oriented pearlite on hydrogen assisted fatigue crack growth. Test specimens were oriented in the steel pipe such that cracks propagated either parallel or perpendicular to the banded pearlite. The ferrite-pearlite microstructure exhibited orientation dependent behavior in which fatigue crack growth rates were significantly lower for cracks oriented perpendicular to the banded pearlite compared to cracks oriented parallel to the bands. Thus the reduction of hydrogen assisted fatigue crack growth across the banded pearlite is attributed to a combination of crack-tip branching and impededmore » hydrogen diffusion across the banded pearlite.« less

A simple object-oriented and open-source model for scientific and policy analyses of the global climate system – Hector v1.0

DOE PAGES

Hartin, Corinne A.; Patel, Pralit L.; Schwarber, Adria; ...

2015-04-01

Simple climate models play an integral role in the policy and scientific communities. They are used for climate mitigation scenarios within integrated assessment models, complex climate model emulation, and uncertainty analyses. Here we describe Hector v1.0, an open source, object-oriented, simple global climate carbon-cycle model. This model runs essentially instantaneously while still representing the most critical global-scale earth system processes. Hector has a three-part main carbon cycle: a one-pool atmosphere, land, and ocean. The model's terrestrial carbon cycle includes primary production and respiration fluxes, accommodating arbitrary geographic divisions into, e.g., ecological biomes or political units. Hector actively solves the inorganicmore » carbon system in the surface ocean, directly calculating air–sea fluxes of carbon and ocean pH. Hector reproduces the global historical trends of atmospheric [CO 2], radiative forcing, and surface temperatures. The model simulates all four Representative Concentration Pathways (RCPs) with equivalent rates of change of key variables over time compared to current observations, MAGICC (a well-known simple climate model), and models from the 5th Coupled Model Intercomparison Project. Hector's flexibility, open-source nature, and modular design will facilitate a broad range of research in various areas.« less

DIAC object recognition system

NASA Astrophysics Data System (ADS)

Buurman, Johannes

1992-03-01

This paper describes the object recognition system used in an intelligent robot cell. It is used to recognize and estimate pose and orientation of parts as they enter the cell. The parts are mostly metal and consist of polyhedral and cylindrical shapes. The system uses feature-based stereo vision to acquire a wireframe of the observed part. Features are defined as straight lines and ellipses, which lead to a wireframe of straight lines and circular arcs (the latter using a new algorithm). This wireframe is compared to a number of wire frame models obtained from the CAD database. Experimental results show that image processing hardware and parallelization may add considerably to the speed of the system.

Relative saliency in change signals affects perceptual comparison and decision processes in change detection.

PubMed

Yang, Cheng-Ta

2011-12-01

Change detection requires perceptual comparison and decision processes on different features of multiattribute objects. How relative salience between two feature-changes influences the processes has not been addressed. This study used the systems factorial technology to investigate the processes when detecting changes in a Gabor patch with visual inputs from orientation and spatial frequency channels. Two feature-changes were equally salient in Experiment 1, but a frequency-change was more salient than an orientation-change in Experiment 2. Results showed that all four observers adopted parallel self-terminating processing with limited- to unlimited-capacity processing in Experiment 1. In Experiment 2, one observer used parallel self-terminating processing with unlimited-capacity processing, and the others adopted serial self-terminating processing with limited- to unlimited-capacity processing to detect changes. Postexperimental interview revealed that subjective utility of feature information underlay the adoption of a decision strategy. These results highlight that observers alter decision strategies in change detection depending on the relative saliency in change signals, with relative saliency being determined by both physical salience and subjective weight of feature information. When relative salience exists, individual differences in the process characteristics emerge.

Xyce™ Parallel Electronic Simulator Users' Guide, Version 6.5.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R.; Aadithya, Karthik V.; Mei, Ting

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to developmore » new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandia's needs, including some radiation- aware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase -- a message passing parallel implementation -- which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows. The information herein is subject to change without notice. Copyright © 2002-2016 Sandia Corporation. All rights reserved.« less

Fabric analysis of quartzites with negative magnetic susceptibility - Does AMS provide information of SPO or CPO of quartz?

NASA Astrophysics Data System (ADS)

Renjith, A. R.; Mamtani, Manish A.; Urai, Janos L.

2016-01-01

We ask the question whether petrofabric data from anisotropy of magnetic susceptibility (AMS) analysis of deformed quartzites gives information about shape preferred orientation (SPO) or crystallographic preferred orientation (CPO) of quartz. Since quartz is diamagnetic and has a negative magnetic susceptibility, 11 samples of nearly pure quartzites with a negative magnetic susceptibility were chosen for this study. After performing AMS analysis, electron backscatter diffraction (EBSD) analysis was done in thin sections prepared parallel to the K1K3 plane of the AMS ellipsoid. Results show that in all the samples quartz SPO is sub-parallel to the orientation of the magnetic foliation. However, in most samples no clear correspondance is observed between quartz CPO and K1 (magnetic lineation) direction. This is contrary to the parallelism observed between K1 direction and orientation of quartz c-axis in the case of undeformed single quartz crystal. Pole figures of quartz indicate that quartz c-axis tends to be parallel to K1 direction only in the case where intracrystalline deformation of quartz is accommodated by prism slip. It is therefore established that AMS investigation of quartz from deformed rocks gives information of SPO. Thus, it is concluded that petrofabric information of quartzite obtained from AMS is a manifestation of its shape anisotropy and not crystallographic preferred orientation.

Multi-threading: A new dimension to massively parallel scientific computation

NASA Astrophysics Data System (ADS)

Nielsen, Ida M. B.; Janssen, Curtis L.

2000-06-01

Multi-threading is becoming widely available for Unix-like operating systems, and the application of multi-threading opens new ways for performing parallel computations with greater efficiency. We here briefly discuss the principles of multi-threading and illustrate the application of multi-threading for a massively parallel direct four-index transformation of electron repulsion integrals. Finally, other potential applications of multi-threading in scientific computing are outlined.

Electrodeposition of ZnO nanorod arrays on ZnO substrate with tunable orientation and optical properties.

PubMed

Jehl, Z; Rousset, J; Donsanti, F; Renou, G; Naghavi, N; Lincot, D

2010-10-01

The electrodeposition of ZnO nanorods on ZnO:Al films with different orientations is reported. The influence of the total charge exchanged during electrodeposition on the nanorod's geometry (length, diameter, aspect ratio and surface density) and the optical transmission properties of the nanorod arrays is studied on a [0001]-oriented ZnO:Al substrate. The nanorods are highly vertically oriented along the c axis, following the lattice matching with the substrate. The growth on a [1010] and [1120] ZnO:Al-oriented substrate with c axis parallel to the substrate leads to a systematic deviation angle of 55 degrees from the perpendicular direction. This finding has been explained by the occurrence of a minority orientation with the [1011] planes parallel to the surface, with a preferential growth on corresponding [0001] termination. Substrate crystalline orientation is thereby found to be a major parameter in finely tuning the orientation of the nanorod array. This new approach allows us to optimize the light scattering properties of the films.

Evolution of Scientific and Technical Information Distribution

NASA Technical Reports Server (NTRS)

Esler, Sandra; Nelson, Michael L.

1998-01-01

World Wide Web (WWW) and related information technologies are transforming the distribution of scientific and technical information (STI). We examine 11 recent, functioning digital libraries focusing on the distribution of STI publications, including journal articles, conference papers, and technical reports. We introduce 4 main categories of digital library projects: based on the architecture (distributed vs. centralized) and the contributor (traditional publisher vs. authoring individual/organization). Many digital library prototypes merely automate existing publishing practices or focus solely on the digitization of the publishing cycle output, not sampling and capturing elements of the input. Still others do not consider for distribution the large body of "gray literature." We address these deficiencies in the current model of STI exchange by suggesting methods for expanding the scope and target of digital libraries by focusing on a greater source of technical publications and using "buckets," an object-oriented construct for grouping logically related information objects, to include holdings other than technical publications.

SCORPIO: A Scalable Two-Phase Parallel I/O Library With Application To A Large Scale Subsurface Simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreepathi, Sarat; Sripathi, Vamsi; Mills, Richard T

2013-01-01

Inefficient parallel I/O is known to be a major bottleneck among scientific applications employed on supercomputers as the number of processor cores grows into the thousands. Our prior experience indicated that parallel I/O libraries such as HDF5 that rely on MPI-IO do not scale well beyond 10K processor cores, especially on parallel file systems (like Lustre) with single point of resource contention. Our previous optimization efforts for a massively parallel multi-phase and multi-component subsurface simulator (PFLOTRAN) led to a two-phase I/O approach at the application level where a set of designated processes participate in the I/O process by splitting themore » I/O operation into a communication phase and a disk I/O phase. The designated I/O processes are created by splitting the MPI global communicator into multiple sub-communicators. The root process in each sub-communicator is responsible for performing the I/O operations for the entire group and then distributing the data to rest of the group. This approach resulted in over 25X speedup in HDF I/O read performance and 3X speedup in write performance for PFLOTRAN at over 100K processor cores on the ORNL Jaguar supercomputer. This research describes the design and development of a general purpose parallel I/O library, SCORPIO (SCalable block-ORiented Parallel I/O) that incorporates our optimized two-phase I/O approach. The library provides a simplified higher level abstraction to the user, sitting atop existing parallel I/O libraries (such as HDF5) and implements optimized I/O access patterns that can scale on larger number of processors. Performance results with standard benchmark problems and PFLOTRAN indicate that our library is able to maintain the same speedups as before with the added flexibility of being applicable to a wider range of I/O intensive applications.« less

Multiple components of surround modulation in primary visual cortex: multiple neural circuits with multiple functions?

PubMed Central

Nurminen, Lauri; Angelucci, Alessandra

2014-01-01

The responses of neurons in primary visual cortex (V1) to stimulation of their receptive field (RF) are modulated by stimuli in the RF surround. This modulation is suppressive when the stimuli in the RF and surround are of similar orientation, but less suppressive or facilitatory when they are cross-oriented. Similarly, in human vision surround stimuli selectively suppress the perceived contrast of a central stimulus. Although the properties of surround modulation have been thoroughly characterized in many species, cortical areas and sensory modalities, its role in perception remains unknown. Here we argue that surround modulation in V1 consists of multiple components having different spatio-temporal and tuning properties, generated by different neural circuits and serving different visual functions. One component arises from LGN afferents, is fast, untuned for orientation, and spatially restricted to the surround region nearest to the RF (the near-surround); its function is to normalize V1 cell responses to local contrast. Intra-V1 horizontal connections contribute a slower, narrowly orientation-tuned component to near-surround modulation, whose function is to increase the coding efficiency of natural images in manner that leads to the extraction of object boundaries. The third component is generated by topdown feedback connections to V1, is fast, broadly orientation-tuned, and extends into the far-surround; its function is to enhance the salience of behaviorally relevant visual features. Far- and near-surround modulation, thus, act as parallel mechanisms: the former quickly detects and guides saccades/attention to salient visual scene locations, the latter segments object boundaries in the scene. PMID:25204770

An Application Server for Scientific Collaboration

NASA Astrophysics Data System (ADS)

Cary, John R.; Luetkemeyer, Kelly G.

1998-11-01

Tech-X Corporation has developed SciChat, an application server for scientific collaboration. Connections are made to the server through a Java client, that can either be an application or an applet served in a web page. Once connected, the client may choose to start or join a session. A session includes not only other clients, but also an application. Any client can send a command to the application. This command is executed on the server and echoed to all clients. The results of the command, whether numerical or graphical, are then distributed to all of the clients; thus, multiple clients can interact collaboratively with a single application. The client is developed in Java, the server in C++, and the middleware is the Common Object Request Broker Architecture. In this system, the Graphical User Interface processing is on the client machine, so one does not have the disadvantages of insufficient bandwidth as occurs when running X over the internet. Because the server, client, and middleware are object oriented, new types of servers and clients specialized to particular scientific applications are more easily developed.

3D highly oriented nanoparticulate and microparticulate array ofmetal oxide materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vayssieres, Lionel; Guo, Jinghua; Nordgren, Joseph

2006-09-15

Advanced nano and micro particulate thin films of 3d transition and post-transition metal oxides consisting of nanorods and microrods with parallel and perpendicular orientation with respect to the substrate normal, have been successfully grown onto various substrates by heteronucleation, without template and/or surfactant, from the aqueous condensation of solution of metal salts or metal complexes (aqueous chemical growth). Three-dimensional arrays of iron oxide nanorods and zinc oxide nanorods with parallel and perpendicular orientation are presented as well as the oxygen K-edge polarization dependent x-ray absorption spectroscopy (XAS) study of anisotropic perpendicularly oriented microrod array of ZnO performed at synchrotron radiationmore » source facility.« less

Progress on H5Part: A Portable High Performance Parallel DataInterface for Electromagnetics Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adelmann, Andreas; Gsell, Achim; Oswald, Benedikt

Significant problems facing all experimental andcomputationalsciences arise from growing data size and complexity. Commonto allthese problems is the need to perform efficient data I/O ondiversecomputer architectures. In our scientific application, thelargestparallel particle simulations generate vast quantitiesofsix-dimensional data. Such a simulation run produces data foranaggregate data size up to several TB per run. Motived by the needtoaddress data I/O and access challenges, we have implemented H5Part,anopen source data I/O API that simplifies the use of the HierarchicalDataFormat v5 library (HDF5). HDF5 is an industry standard forhighperformance, cross-platform data storage and retrieval that runsonall contemporary architectures from large parallel supercomputerstolaptops. H5Part, whichmore » is oriented to the needs of the particlephysicsand cosmology communities, provides support for parallelstorage andretrieval of particles, structured and in the future unstructuredmeshes.In this paper, we describe recent work focusing on I/O supportforparticles and structured meshes and provide data showing performance onmodernsupercomputer architectures like the IBM POWER 5.« less

Orientation selective deep brain stimulation

NASA Astrophysics Data System (ADS)

Lehto, Lauri J.; Slopsema, Julia P.; Johnson, Matthew D.; Shatillo, Artem; Teplitzky, Benjamin A.; Utecht, Lynn; Adriany, Gregor; Mangia, Silvia; Sierra, Alejandra; Low, Walter C.; Gröhn, Olli; Michaeli, Shalom

2017-02-01

Objective. Target selectivity of deep brain stimulation (DBS) therapy is critical, as the precise locus and pattern of the stimulation dictates the degree to which desired treatment responses are achieved and adverse side effects are avoided. There is a clear clinical need to improve DBS technology beyond currently available stimulation steering and shaping approaches. We introduce orientation selective neural stimulation as a concept to increase the specificity of target selection in DBS. Approach. This concept, which involves orienting the electric field along an axonal pathway, was tested in the corpus callosum of the rat brain by freely controlling the direction of the electric field on a plane using a three-electrode bundle, and monitoring the response of the neurons using functional magnetic resonance imaging (fMRI). Computational models were developed to further analyze axonal excitability for varied electric field orientation. Main results. Our results demonstrated that the strongest fMRI response was observed when the electric field was oriented parallel to the axons, while almost no response was detected with the perpendicular orientation of the electric field relative to the primary fiber tract. These results were confirmed by computational models of the experimental paradigm quantifying the activation of radially distributed axons while varying the primary direction of the electric field. Significance. The described strategies identify a new course for selective neuromodulation paradigms in DBS based on axonal fiber orientation.

Draco,Version 6.x.x

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, Kelly; Budge, Kent; Lowrie, Rob

2016-03-03

Draco is an object-oriented component library geared towards numerically intensive, radiation (particle) transport applications built for parallel computing hardware. It consists of semi-independent packages and a robust build system. The packages in Draco provide a set of components that can be used by multiple clients to build transport codes. The build system can also be extracted for use in clients. Software includes smart pointers, Design-by-Contract assertions, unit test framework, wrapped MPI functions, a file parser, unstructured mesh data structures, a random number generator, root finders and an angular quadrature component.

An engineering approach to automatic programming

NASA Technical Reports Server (NTRS)

Rubin, Stuart H.

1990-01-01

An exploratory study of the automatic generation and optimization of symbolic programs using DECOM - a prototypical requirement specification model implemented in pure LISP was undertaken. It was concluded, on the basis of this study, that symbolic processing languages such as LISP can support a style of programming based upon formal transformation and dependent upon the expression of constraints in an object-oriented environment. Such languages can represent all aspects of the software generation process (including heuristic algorithms for effecting parallel search) as dynamic processes since data and program are represented in a uniform format.

Idle waves in high-performance computing

NASA Astrophysics Data System (ADS)

Markidis, Stefano; Vencels, Juris; Peng, Ivy Bo; Akhmetova, Dana; Laure, Erwin; Henri, Pierre

2015-01-01

The vast majority of parallel scientific applications distributes computation among processes that are in a busy state when computing and in an idle state when waiting for information from other processes. We identify the propagation of idle waves through processes in scientific applications with a local information exchange between the two processes. Idle waves are nondispersive and have a phase velocity inversely proportional to the average busy time. The physical mechanism enabling the propagation of idle waves is the local synchronization between two processes due to remote data dependency. This study provides a description of the large number of processes in parallel scientific applications as a continuous medium. This work also is a step towards an understanding of how localized idle periods can affect remote processes, leading to the degradation of global performance in parallel scientific applications.

An object-oriented approach for parallel self adaptive mesh refinement on block structured grids

NASA Technical Reports Server (NTRS)

Lemke, Max; Witsch, Kristian; Quinlan, Daniel

1993-01-01

Self-adaptive mesh refinement dynamically matches the computational demands of a solver for partial differential equations to the activity in the application's domain. In this paper we present two C++ class libraries, P++ and AMR++, which significantly simplify the development of sophisticated adaptive mesh refinement codes on (massively) parallel distributed memory architectures. The development is based on our previous research in this area. The C++ class libraries provide abstractions to separate the issues of developing parallel adaptive mesh refinement applications into those of parallelism, abstracted by P++, and adaptive mesh refinement, abstracted by AMR++. P++ is a parallel array class library to permit efficient development of architecture independent codes for structured grid applications, and AMR++ provides support for self-adaptive mesh refinement on block-structured grids of rectangular non-overlapping blocks. Using these libraries, the application programmers' work is greatly simplified to primarily specifying the serial single grid application and obtaining the parallel and self-adaptive mesh refinement code with minimal effort. Initial results for simple singular perturbation problems solved by self-adaptive multilevel techniques (FAC, AFAC), being implemented on the basis of prototypes of the P++/AMR++ environment, are presented. Singular perturbation problems frequently arise in large applications, e.g. in the area of computational fluid dynamics. They usually have solutions with layers which require adaptive mesh refinement and fast basic solvers in order to be resolved efficiently.

[An object-oriented intelligent engineering design approach for lake pollution control].

PubMed

Zou, Rui; Zhou, Jing; Liu, Yong; Zhu, Xiang; Zhao, Lei; Yang, Ping-Jian; Guo, Huai-Cheng

2013-03-01

Regarding the shortage and deficiency of traditional lake pollution control engineering techniques, a new lake pollution control engineering approach was proposed in this study, based on object-oriented intelligent design (OOID) from the perspective of intelligence. It can provide a new methodology and framework for effectively controlling lake pollution and improving water quality. The differences between the traditional engineering techniques and the OOID approach were compared. The key points for OOID were described as object perspective, cause and effect foundation, set points into surface, and temporal and spatial optimization. The blue algae control in lake was taken as an example in this study. The effect of algae control and water quality improvement were analyzed in details from the perspective of object-oriented intelligent design based on two engineering techniques (vertical hydrodynamic mixer and pumping algaecide recharge). The modeling results showed that the traditional engineering design paradigm cannot provide scientific and effective guidance for engineering design and decision-making regarding lake pollution. Intelligent design approach is based on the object perspective and quantitative causal analysis in this case. This approach identified that the efficiency of mixers was much higher than pumps in achieving the goal of low to moderate water quality improvement. However, when the objective of water quality exceeded a certain value (such as the control objective of peak Chla concentration exceeded 100 microg x L(-1) in this experimental water), the mixer cannot achieve this goal. The pump technique can achieve the goal but with higher cost. The efficiency of combining the two techniques was higher than using one of the two techniques alone. Moreover, the quantitative scale control of the two engineering techniques has a significant impact on the actual project benefits and costs.

Comparative study of bowtie and patient scatter in diagnostic CT

NASA Astrophysics Data System (ADS)

Prakash, Prakhar; Boudry, John M.

2017-03-01

A fast, GPU accelerated Monte Carlo engine for simulating relevant photon interaction processes over the diagnostic energy range in third-generation CT systems was developed to study the relative contributions of bowtie and object scatter to the total scatter reaching an imaging detector. Primary and scattered projections for an elliptical water phantom (major axis set to 300mm) with muscle and fat inserts were simulated for a typical diagnostic CT system as a function of anti-scatter grid (ASG) configurations. The ASG design space explored grid orientation, i.e. septa either a) parallel or b) parallel and perpendicular to the axis of rotation, as well as septa height. The septa material was Tungsten. The resulting projections were reconstructed and the scatter induced image degradation was quantified using common CT image metrics (such as Hounsfield Unit (HU) inaccuracy and loss in contrast), along with a qualitative review of image artifacts. Results indicate object scatter dominates total scatter in the detector channels under the shadow of the imaged object with the bowtie scatter fraction progressively increasing towards the edges of the object projection. Object scatter was shown to be the driving factor behind HU inaccuracy and contrast reduction in the simulated images while shading artifacts and elevated loss in HU accuracy at the object boundary were largely attributed to bowtie scatter. Because the impact of bowtie scatter could not be sufficiently mitigated with a large grid ratio ASG, algorithmic correction may be necessary to further mitigate these artifacts.

Neptune: An astrophysical smooth particle hydrodynamics code for massively parallel computer architectures

NASA Astrophysics Data System (ADS)

Sandalski, Stou

Smooth particle hydrodynamics is an efficient method for modeling the dynamics of fluids. It is commonly used to simulate astrophysical processes such as binary mergers. We present a newly developed GPU accelerated smooth particle hydrodynamics code for astrophysical simulations. The code is named neptune after the Roman god of water. It is written in OpenMP parallelized C++ and OpenCL and includes octree based hydrodynamic and gravitational acceleration. The design relies on object-oriented methodologies in order to provide a flexible and modular framework that can be easily extended and modified by the user. Several pre-built scenarios for simulating collisions of polytropes and black-hole accretion are provided. The code is released under the MIT Open Source license and publicly available at http://code.google.com/p/neptune-sph/.

Are the religious suspicious of science? Investigating religiosity, religious context, and orientations towards science.

PubMed

Chan, Esther

2018-06-01

Are the religious suspicious of science? Drawing on data from 52 nations in the World Values Survey (wave 6) ( N = 58,474), I utilize multilevel models to examine the relationship between religiosity, religious context, and five different orientations towards science: confidence in science, trust in scientific authority under conditions of conflict with religion, faith in science, views on the moral effects of science, and interest in scientific knowledge. Results show that while religiosity is on average negatively associated with the five outcomes, the relationship between religiosity and orientations towards science varies by country such that religiosity is sometimes positively associated with the different outcomes. Religiosity is only consistently negatively associated with trust in scientific authority in all countries and with all orientations towards science in western countries. Finally, differences in orientations towards science also exist across country religious contexts, with countries dominated by the unaffiliated having more positive orientations towards science.

Large-scale trench-normal mantle flow beneath central South America

NASA Astrophysics Data System (ADS)

Reiss, M. C.; Rümpker, G.; Wölbern, I.

2018-01-01

We investigate the anisotropic properties of the fore-arc region of the central Andean margin between 17-25°S by analyzing shear-wave splitting from teleseismic and local earthquakes from the Nazca slab. With partly over ten years of recording time, the data set is uniquely suited to address the long-standing debate about the mantle flow field at the South American margin and in particular whether the flow field beneath the slab is parallel or perpendicular to the trench. Our measurements suggest two anisotropic layers located within the crust and mantle beneath the stations, respectively. The teleseismic measurements show a moderate change of fast polarizations from North to South along the trench ranging from parallel to subparallel to the absolute plate motion and, are oriented mostly perpendicular to the trench. Shear-wave splitting measurements from local earthquakes show fast polarizations roughly aligned trench-parallel but exhibit short-scale variations which are indicative of a relatively shallow origin. Comparisons between fast polarization directions from local earthquakes and the strike of the local fault systems yield a good agreement. To infer the parameters of the lower anisotropic layer we employ an inversion of the teleseismic waveforms based on two-layer models, where the anisotropy of the upper (crustal) layer is constrained by the results from the local splitting. The waveform inversion yields a mantle layer that is best characterized by a fast axis parallel to the absolute plate motion which is more-or-less perpendicular to the trench. This orientation is likely caused by a combination of the fossil crystallographic preferred orientation of olivine within the slab and entrained mantle flow beneath the slab. The anisotropy within the crust of the overriding continental plate is explained by the shape-preferred orientation of micro-cracks in relation to local fault zones which are oriented parallel to the overall strike of the Andean range. Our results do not provide any evidence for a significant contribution of trench-parallel mantle flow beneath the subducting slab.

Matching traditional and scientific observations to detect environmental change: a discussion on Arctic terrestrial ecosystems.

PubMed

Huntington, Henry; Callaghan, Terry; Fox, Shari; Krupnik, Igor

2004-11-01

Recent environmental changes are having, and are expected to continue to have, significant impacts in the Arctic as elsewhere in the world. Detecting those changes and determining the mechanisms that cause them are far from trivial problems. The use of multiple methods of observation can increase confidence in individual observations, broaden the scope of information available about environmental change, and contribute to insights concerning mechanisms of change. In this paper, we examine the ways that using traditional ecological knowledge (TEK) together with scientific observations can achieve these objectives. A review of TEK observations in comparison with scientific observations demonstrates the promise of this approach, while also revealing several challenges to putting it into practice on a large scale. Further efforts are suggested, particularly in undertaking collaborative projects designed to produce parallel observations that can be readily compared and analyzed in greater detail than is possible in an opportunistic sample.

Effects of visual information regarding allocentric processing in haptic parallelity matching.

PubMed

Van Mier, Hanneke I

2013-10-01

Research has revealed that haptic perception of parallelity deviates from physical reality. Large and systematic deviations have been found in haptic parallelity matching most likely due to the influence of the hand-centered egocentric reference frame. Providing information that increases the influence of allocentric processing has been shown to improve performance on haptic matching. In this study allocentric processing was stimulated by providing informative vision in haptic matching tasks that were performed using hand- and arm-centered reference frames. Twenty blindfolded participants (ten men, ten women) explored the orientation of a reference bar with the non-dominant hand and subsequently matched (task HP) or mirrored (task HM) its orientation on a test bar with the dominant hand. Visual information was provided by means of informative vision with participants having full view of the test bar, while the reference bar was blocked from their view (task VHP). To decrease the egocentric bias of the hands, participants also performed a visual haptic parallelity drawing task (task VHPD) using an arm-centered reference frame, by drawing the orientation of the reference bar. In all tasks, the distance between and orientation of the bars were manipulated. A significant effect of task was found; performance improved from task HP, to VHP to VHPD, and HM. Significant effects of distance were found in the first three tasks, whereas orientation and gender effects were only significant in tasks HP and VHP. The results showed that stimulating allocentric processing by means of informative vision and reducing the egocentric bias by using an arm-centered reference frame led to most accurate performance on parallelity matching. © 2013 Elsevier B.V. All rights reserved.

Effect of anisotropy and texture on the low cycle fatigue behavior of Inconel 718 processed via electron beam melting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirka, Michael M.; Greeley, Duncan A.; Hawkins, Charles S.

Here in this study, the impact of texture (columnar/equiax grain structure) and influence of material orientation on the low cycle fatigue (LCF) behavior of hot isostatic pressed (HIP) and heat-treated Inconel 718 fabricated through electron beam melting (EBM) is investigated. Material was tested both parallel and perpendicular (transverse) to the build direction. In all instances, the EBM HIP and heat-treated Inconel 718 performed similarly or exceeded the LCF life of wrought Inconel 718 plate and bar stock under fully reversed strain-controlled loading at 650 °C. Amongst the textures, the columnar grains oriented parallel to the build direction exhibited the highestmore » life on average compared to the transverse columnar and equiax EBM material. Further, in relation to the reference wrought material the parallel columnar grain material exhibited a greater life. While a negligible life difference was observed in the equiax grained material between the two orientations, a consistently lower accumulated inelastic strain was measured for the material loaded parallel to the build direction than the transverse orientation. Failure of the parallel columnar material occurred in a transgranular manner with cracks emanating from the surface whereas the transverse columnar material failed in a intergranular manner, with crack growth occurring through repeated rupture of oxide at the crack-tip. Finally, in the case of the equiax material, an influence of material orientation was not observed on the failure mechanism with crack propagation occurring through a combination of debonded/cracked carbides and void formation along twin boundaries resulting in a mixture of intergranular and transgranular crack propagation.« less

Effect of anisotropy and texture on the low cycle fatigue behavior of Inconel 718 processed via electron beam melting

DOE PAGES

Kirka, Michael M.; Greeley, Duncan A.; Hawkins, Charles S.; ...

2017-09-11

Here in this study, the impact of texture (columnar/equiax grain structure) and influence of material orientation on the low cycle fatigue (LCF) behavior of hot isostatic pressed (HIP) and heat-treated Inconel 718 fabricated through electron beam melting (EBM) is investigated. Material was tested both parallel and perpendicular (transverse) to the build direction. In all instances, the EBM HIP and heat-treated Inconel 718 performed similarly or exceeded the LCF life of wrought Inconel 718 plate and bar stock under fully reversed strain-controlled loading at 650 °C. Amongst the textures, the columnar grains oriented parallel to the build direction exhibited the highestmore » life on average compared to the transverse columnar and equiax EBM material. Further, in relation to the reference wrought material the parallel columnar grain material exhibited a greater life. While a negligible life difference was observed in the equiax grained material between the two orientations, a consistently lower accumulated inelastic strain was measured for the material loaded parallel to the build direction than the transverse orientation. Failure of the parallel columnar material occurred in a transgranular manner with cracks emanating from the surface whereas the transverse columnar material failed in a intergranular manner, with crack growth occurring through repeated rupture of oxide at the crack-tip. Finally, in the case of the equiax material, an influence of material orientation was not observed on the failure mechanism with crack propagation occurring through a combination of debonded/cracked carbides and void formation along twin boundaries resulting in a mixture of intergranular and transgranular crack propagation.« less

Reliability of a science admission test (HAM-Nat) at Hamburg medical school

PubMed Central

Hissbach, Johanna; Klusmann, Dietrich; Hampe, Wolfgang

2011-01-01

Objective: The University Hospital in Hamburg (UKE) started to develop a test of knowledge in natural sciences for admission to medical school in 2005 (Hamburger Auswahlverfahren für Medizinische Studiengänge, Naturwissenschaftsteil, HAM-Nat). This study is a step towards establishing the HAM-Nat. We are investigating parallel forms reliability, the effect of a crash course in chemistry on test results, and correlations of HAM-Nat test results with a test of scientific reasoning (similar to a subtest of the "Test for Medical Studies", TMS). Methods: 316 first-year students participated in the study in 2007. They completed different versions of the HAM-Nat test which consisted of items that had already been used (HN2006) and new items (HN2007). Four weeks later half of the participants were tested on the HN2007 version of the HAM-Nat again, while the other half completed the test of scientific reasoning. Within this four week interval students were offered a five day chemistry course. Results: Parallel forms reliability for four different test versions ranged from rtt=.53 to rtt=.67. The retest reliabilities of the HN2007 halves were rtt=.54 and rtt =.61. Correlations of the two HAM-Nat versions with the test of scientific reasoning were r=.34 und r=.21. The crash course in chemistry had no effect on HAM-Nat scores. Conclusions: The results suggest that further versions of the test of natural sciences will not easily conform to the standards of internal consistency, parallel-forms reliability and retest reliability. Much care has to be taken in order to assemble items which could be used interchangeably for the construction of new test versions. The test of scientific reasoning and the HAM-Nat are tapping different constructs. Participation in a chemistry course did not improve students’ achievement, probably because the content of the course was not coordinated with the test and many students lacked of motivation to do well in the second test. PMID:21866246

PFLOTRAN: Reactive Flow & Transport Code for Use on Laptops to Leadership-Class Supercomputers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hammond, Glenn E.; Lichtner, Peter C.; Lu, Chuan

PFLOTRAN, a next-generation reactive flow and transport code for modeling subsurface processes, has been designed from the ground up to run efficiently on machines ranging from leadership-class supercomputers to laptops. Based on an object-oriented design, the code is easily extensible to incorporate additional processes. It can interface seamlessly with Fortran 9X, C and C++ codes. Domain decomposition parallelism is employed, with the PETSc parallel framework used to manage parallel solvers, data structures and communication. Features of the code include a modular input file, implementation of high-performance I/O using parallel HDF5, ability to perform multiple realization simulations with multiple processors permore » realization in a seamless manner, and multiple modes for multiphase flow and multicomponent geochemical transport. Chemical reactions currently implemented in the code include homogeneous aqueous complexing reactions and heterogeneous mineral precipitation/dissolution, ion exchange, surface complexation and a multirate kinetic sorption model. PFLOTRAN has demonstrated petascale performance using 2{sup 17} processor cores with over 2 billion degrees of freedom. Accomplishments achieved to date include applications to the Hanford 300 Area and modeling CO{sub 2} sequestration in deep geologic formations.« less

Multidimensional Environmental Data Resource Brokering on Computational Grids and Scientific Clouds

NASA Astrophysics Data System (ADS)

Montella, Raffaele; Giunta, Giulio; Laccetti, Giuliano

Grid computing has widely evolved over the past years, and its capabilities have found their way even into business products and are no longer relegated to scientific applications. Today, grid computing technology is not restricted to a set of specific grid open source or industrial products, but rather it is comprised of a set of capabilities virtually within any kind of software to create shared and highly collaborative production environments. These environments are focused on computational (workload) capabilities and the integration of information (data) into those computational capabilities. An active grid computing application field is the fully virtualization of scientific instruments in order to increase their availability and decrease operational and maintaining costs. Computational and information grids allow to manage real-world objects in a service-oriented way using industrial world-spread standards.

Load Balancing Scientific Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pearce, Olga Tkachyshyn

2014-12-01

The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one atmore » the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.« less

Developing instruments concerning scientific epistemic beliefs and goal orientations in learning science: a validation study

NASA Astrophysics Data System (ADS)

Lin, Tzung-Jin; Tsai, Chin-Chung

2017-11-01

The purpose of this study was to develop and validate two survey instruments to evaluate high school students' scientific epistemic beliefs and goal orientations in learning science. The initial relationships between the sampled students' scientific epistemic beliefs and goal orientations in learning science were also investigated. A final valid sample of 600 volunteer Taiwanese high school students participated in this survey by responding to the Scientific Epistemic Beliefs Instrument (SEBI) and the Goal Orientations in Learning Science Instrument (GOLSI). Through both exploratory and confirmatory factor analyses, the SEBI and GOLSI were proven to be valid and reliable for assessing the participants' scientific epistemic beliefs and goal orientations in learning science. The path analysis results indicated that, by and large, the students with more sophisticated epistemic beliefs in various dimensions such as Development of Knowledge, Justification for Knowing, and Purpose of Knowing tended to adopt both Mastery-approach and Mastery-avoidance goals. Some interesting results were also found. For example, the students tended to set a learning goal to outperform others or merely demonstrate competence (Performance-approach) if they had more informed epistemic beliefs in the dimensions of Multiplicity of Knowledge, Uncertainty of Knowledge, and Purpose of Knowing.

Bringing science to medicine: an interview with Larry Weed, inventor of the problem-oriented medical record.

PubMed

Wright, Adam; Sittig, Dean F; McGowan, Julie; Ash, Joan S; Weed, Lawrence L

2014-01-01

Larry Weed, MD is widely known as the father of the problem-oriented medical record and inventor of the now-ubiquitous SOAP (subjective/objective/assessment/plan) note, for developing an electronic health record system (Problem-Oriented Medical Information System, PROMIS), and for founding a company (since acquired), which developed problem-knowledge couplers. However, Dr Weed's vision for medicine goes far beyond software--over the course of his storied career, he has relentlessly sought to bring the scientific method to medical practice and, where necessary, to point out shortcomings in the system and advocate for change. In this oral history, Dr Weed describes, in his own words, the arcs of his long career and the work that remains to be done. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Identification of Behavioral Indicators in Political Protest Music

DTIC Science & Technology

2015-12-01

to ways to influence that behavior. Political protest songs are one such source. Protest music is goal-oriented, and lyrics often parallel movement ... music is goal-oriented, and lyrics often parallel movement goals of potential TAs. This thesis examines how political protest music can help identify... movement theory in order to bridge the MISO doctrine with music theories and understand what influences people to change their behavior and act or

Scalable alignment and transfer of nanowires based on oriented polymer nanofibers.

PubMed

Yan, Shancheng; Lu, Lanxin; Meng, Hao; Huang, Ningping; Xiao, Zhongdang

2010-03-05

We develop a simple and scalable method based on oriented polymer nanofiber films for the parallel assembly and transfer of nanowires at high density. Nanowires dispersed in solution are aligned and selectively deposited at the central space of parallel nanochannels formed by the well-oriented nanofibers as a result of evaporation-induced flow and capillarity. A general contact printing method is used to realize the transfer of the nanowires from the donor nanofiber film to a receiver substrate. The mechanism, which involves ordered alignment of nanowires on oriented polymer nanofiber films, is also explored with an evaporation model of cylindrical droplets. The simplicity of the assembly and transfer, and the facile fabrication of large-area well-oriented nanofiber films, make the present method promising for the application of nanowires, especially for the disordered nanowires synthesized by solution chemistry.

Reducing the motor response in haptic parallel matching eliminates the typically observed gender difference.

PubMed

van Mier, Hanneke I

2016-01-01

When making two bars haptically parallel to each other, large deviations have been observed, most likely caused by the bias of a hand-centered egocentric reference frame. A consistent finding is that women show significantly larger deviations than men when performing this task. It has been suggested that this difference might be due to the fact that women are more egocentrically oriented than men or are less efficient in overcoming the egocentric bias of the hand. If this is indeed the case, reducing the bias of the egocentric reference frame should eliminate the above-mentioned gender difference. This was investigated in the current study. Sixty participants (30 men, 30 women) were instructed to haptically match (task HP) the orientation of a test bar with the dominant hand to the orientation of a reference bar that was perceived with the non-dominant hand. In a haptic visual task (task HV), in which only the reference bar and exploring hand were out of view, no motor response was required, but participants had to "match" the perceived orientation by verbally naming the parallel orientation that was read out on a test protractor. Both females and males performed better in the HV task than in the HP task. Significant gender effects were only found in the haptic parallelity task (HP), corroborating the idea that women perform at the same level as men when the egocentric bias of the hand is reduced.

Sexual Orientation, Controversy, and Science.

PubMed

Bailey, J Michael; Vasey, Paul L; Diamond, Lisa M; Breedlove, S Marc; Vilain, Eric; Epprecht, Marc

2016-09-01

SummaryOngoing political controversies around the world exemplify a long-standing and widespread preoccupation with the acceptability of homosexuality. Nonheterosexual people have seen dramatic surges both in their rights and in positive public opinion in many Western countries. In contrast, in much of Africa, the Middle East, the Caribbean, Oceania, and parts of Asia, homosexual behavior remains illegal and severely punishable, with some countries retaining the death penalty for it. Political controversies about sexual orientation have often overlapped with scientific controversies. That is, participants on both sides of the sociopolitical debates have tended to believe that scientific findings-and scientific truths-about sexual orientation matter a great deal in making political decisions. The most contentious scientific issues have concerned the causes of sexual orientation-that is, why are some people heterosexual, others bisexual, and others homosexual? The actual relevance of these issues to social, political, and ethical decisions is often poorly justified, however. © The Author(s) 2016.

Task-oriented training with computer gaming in people with rheumatoid arthritisor osteoarthritis of the hand: study protocol of a randomized controlled pilot trial

PubMed Central

2013-01-01

Background Significant restriction in the ability to participate in home, work and community life results from pain, fatigue, joint damage, stiffness and reduced joint range of motion and muscle strength in people with rheumatoid arthritis or osteoarthritis of the hand. With modest evidence on the therapeutic effectiveness of conventional hand exercises, a task-oriented training program via real life object manipulations has been developed for people with arthritis. An innovative, computer-based gaming platform that allows a broad range of common objects to be seamlessly transformed into therapeutic input devices through instrumentation with a motion-sense mouse has also been designed. Personalized objects are selected to target specific training goals such as graded finger mobility, strength, endurance or fine/gross dexterous functions. The movements and object manipulation tasks that replicate common situations in everyday living will then be used to control and play any computer game, making practice challenging and engaging. Methods/Design The ongoing study is a 6-week, single-center, parallel-group, equally allocated and assessor-blinded pilot randomized controlled trial. Thirty people with rheumatoid arthritis or osteoarthritis affecting the hand will be randomized to receive either conventional hand exercises or the task-oriented training. The purpose is to determine a preliminary estimation of therapeutic effectiveness and feasibility of the task-oriented training program. Performance based and self-reported hand function, and exercise compliance are the study outcomes. Changes in outcomes (pre to post intervention) within each group will be assessed by paired Student t test or Wilcoxon signed-rank test and between groups (control versus experimental) post intervention using unpaired Student t test or Mann–Whitney U test. Discussion The study findings will inform decisions on the feasibility, safety and completion rate and will also provide preliminary data on the treatment effects of the task-oriented training compared with conventional hand exercises in people with rheumatoid arthritis or osteoarthritis of the hand. Trial registration ClinicalTrials.gov: NCT01635582 PMID:23497529

Structure development in melt processing isotactic polypropylene, polypropylene blends/compounds and dynamically vulcanized polyolefin TPEs

NASA Astrophysics Data System (ADS)

Yu, Yishan

The influence of various fillers, nucleating agents and ethylene propylene diene terpolymer (EPDM) additive on crystalline modification (alpha-, beta- and smectic forms) and crystalline orientation of polypropylene in die extrudates, melt spun filaments, thick rods, blow molded bottles and injection molded parts of isotactic polypropylene (PP), its blends/compounds and dynamically vulcanized polypropylene thermoplastic elastomers (TPEs) were experimentally studied under a range of cooling and processing conditions. The phenomena of crystallization, polymorphism and orientation in processing of both thin and thick samples (filaments, rods, bottles and injection molded parts) were simulated through transport laws incorporating polymer crystallization kinetics. Continuous cooling transformation (CCT) curves for the various material systems investigated were developed under quiescent and uniaxial stress conditions. We applied experimental data on polymorphism of thin sections to predict crystalline structure variation in thick parts. The predictions were consistent with experiments. For filaments, the polypropylene crystalline orientation-spinline stress relationship is generally similar for the neat PP, blends/compounds and TPEs. However, the blends and TPEs have much lower birefringence apparently due to a lack of orientation in the rubber phase. It was shown that the polypropylene contribution to the birefringence for the neat PP and its blends is the same at the same spinline stress. For bottles, the inflation pressures used have little effect on orientation of either polypropylene crystals or disc-shaped talc filler. The talc discs are highly oriented parallel to the bottle surface. For the bottles without talc, the orientation of polypropylene crystallographic axes are low. The polypropylene crystallographic b-axes in the talc filled bottles are more highly oriented. For injection molded parts, it was found that a low orientation layer exists between the part surface and an intermediate highly oriented layer in the parts of neat PP and its blends/compounds. The thickness of this layer increases as the injection pressure decreases. This layer was not formed in the TPE parts. This would seem to be associated with the TPEs exhibiting a yield stress in shear flow and not exhibiting fountain flow in mold filling. For all parts studied, the orientation characteristics of polypropylene crystallographic axes in the highly oriented layer are similar from sample to sample. The strong orientation of the c-axis parallel to the machine direction and the b-axis perpendicular to the machine direction are observed in the highly oriented layer. The talc discs in both the highly oriented layer and the intermediate position are highly oriented parallel to the part face due to melt flow. At intermediate position in the talc-filled parts, the polypropylene crystallographic (040) planes prefer to align themselves parallel to the part surface but are not so well oriented when the talc is absent.

Trace: a high-throughput tomographic reconstruction engine for large-scale datasets

DOE PAGES

Bicer, Tekin; Gursoy, Doga; Andrade, Vincent De; ...

2017-01-28

Here, synchrotron light source and detector technologies enable scientists to perform advanced experiments. These scientific instruments and experiments produce data at such scale and complexity that large-scale computation is required to unleash their full power. One of the widely used data acquisition technique at light sources is Computed Tomography, which can generate tens of GB/s depending on x-ray range. A large-scale tomographic dataset, such as mouse brain, may require hours of computation time with a medium size workstation. In this paper, we present Trace, a data-intensive computing middleware we developed for implementation and parallelization of iterative tomographic reconstruction algorithms. Tracemore » provides fine-grained reconstruction of tomography datasets using both (thread level) shared memory and (process level) distributed memory parallelization. Trace utilizes a special data structure called replicated reconstruction object to maximize application performance. We also present the optimizations we have done on the replicated reconstruction objects and evaluate them using a shale and a mouse brain sinogram. Our experimental evaluations show that the applied optimizations and parallelization techniques can provide 158x speedup (using 32 compute nodes) over single core configuration, which decreases the reconstruction time of a sinogram (with 4501 projections and 22400 detector resolution) from 12.5 hours to less than 5 minutes per iteration.« less

Trace: a high-throughput tomographic reconstruction engine for large-scale datasets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bicer, Tekin; Gursoy, Doga; Andrade, Vincent De

Here, synchrotron light source and detector technologies enable scientists to perform advanced experiments. These scientific instruments and experiments produce data at such scale and complexity that large-scale computation is required to unleash their full power. One of the widely used data acquisition technique at light sources is Computed Tomography, which can generate tens of GB/s depending on x-ray range. A large-scale tomographic dataset, such as mouse brain, may require hours of computation time with a medium size workstation. In this paper, we present Trace, a data-intensive computing middleware we developed for implementation and parallelization of iterative tomographic reconstruction algorithms. Tracemore » provides fine-grained reconstruction of tomography datasets using both (thread level) shared memory and (process level) distributed memory parallelization. Trace utilizes a special data structure called replicated reconstruction object to maximize application performance. We also present the optimizations we have done on the replicated reconstruction objects and evaluate them using a shale and a mouse brain sinogram. Our experimental evaluations show that the applied optimizations and parallelization techniques can provide 158x speedup (using 32 compute nodes) over single core configuration, which decreases the reconstruction time of a sinogram (with 4501 projections and 22400 detector resolution) from 12.5 hours to less than 5 minutes per iteration.« less

Opportunities and choice in a new vector era

NASA Astrophysics Data System (ADS)

Nowak, A.

2014-06-01

This work discusses the significant changes in computing landscape related to the progression of Moore's Law, and the implications on scientific computing. Particular attention is devoted to the High Energy Physics domain (HEP), which has always made good use of threading, but levels of parallelism closer to the hardware were often left underutilized. Findings of the CERN openlab Platform Competence Center are reported in the context of expanding "performance dimensions", and especially the resurgence of vectors. These suggest that data oriented designs are feasible in HEP and have considerable potential for performance improvements on multiple levels, but will rarely trump algorithmic enhancements. Finally, an analysis of upcoming hardware and software technologies identifies heterogeneity as a major challenge for software, which will require more emphasis on scalable, efficient design.

Crustal origin of trench-parallel shear-wave fast polarizations in the Central Andes

NASA Astrophysics Data System (ADS)

Wölbern, I.; Löbl, U.; Rümpker, G.

2014-04-01

In this study, SKS and local S phases are analyzed to investigate variations of shear-wave splitting parameters along two dense seismic profiles across the central Andean Altiplano and Puna plateaus. In contrast to previous observations, the vast majority of the measurements reveal fast polarizations sub-parallel to the subduction direction of the Nazca plate with delay times between 0.3 and 1.2 s. Local phases show larger variations of fast polarizations and exhibit delay times ranging between 0.1 and 1.1 s. Two 70 km and 100 km wide sections along the Altiplano profile exhibit larger delay times and are characterized by fast polarizations oriented sub-parallel to major fault zones. Based on finite-difference wavefield calculations for anisotropic subduction zone models we demonstrate that the observations are best explained by fossil slab anisotropy with fast symmetry axes oriented sub-parallel to the slab movement in combination with a significant component of crustal anisotropy of nearly trench-parallel fast-axis orientation. From the modeling we exclude a sub-lithospheric origin of the observed strong anomalies due to the short-scale variations of the fast polarizations. Instead, our results indicate that anisotropy in the Central Andes generally reflects the direction of plate motion while the observed trench-parallel fast polarizations likely originate in the continental crust above the subducting slab.

A focus on polarity: Investigating the role of orientation cues in mediating student performance on mRNA synthesis tasks in an introductory cell and molecular biology course.

PubMed

Olimpo, Jeffrey T; Quijas, Daniel A; Quintana, Anita M

2017-11-01

The central dogma has served as a foundational model for information flow, exchange, and storage in the biological sciences for several decades. Despite its continued importance, however, recent research suggests that novices in the domain possess several misconceptions regarding the aforementioned processes, including those pertaining specifically to the formation of messenger ribonucleic acid (mRNA) transcripts. In the present study, we sought to expand upon these observations through exploration of the influence of orientation cues on students' aptitude at synthesizing mRNAs from provided deoxyribonucleic acid (DNA) template strands. Data indicated that participants (n = 45) were proficient at solving tasks of this nature when the DNA template strand and the mRNA molecule were represented in an antiparallel orientation. In contrast, participants' performance decreased significantly on items in which the mRNA was depicted in a parallel orientation relative to the DNA template strand. Furthermore, participants' Grade Point Average, self-reported confidence in understanding the transcriptional process, and spatial ability were found to mediate their performance on the mRNA synthesis tasks. Collectively, these data reaffirm the need for future research and pedagogical interventions designed to enhance students' comprehension of the central dogma in a manner that makes transparent its relevance to real-world scientific phenomena. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(6):501-508, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

Crystal Orientation Controlled Photovoltaic Properties of Multilayer GaAs Nanowire Arrays.

PubMed

Han, Ning; Yang, Zai-Xing; Wang, Fengyun; Yip, SenPo; Li, Dapan; Hung, Tak Fu; Chen, Yunfa; Ho, Johnny C

2016-06-28

In recent years, despite significant progress in the synthesis, characterization, and integration of various nanowire (NW) material systems, crystal orientation controlled NW growth as well as real-time assessment of their growth-structure-property relationships still presents one of the major challenges in deploying NWs for practical large-scale applications. In this study, we propose, design, and develop a multilayer NW printing scheme for the determination of crystal orientation controlled photovoltaic properties of parallel GaAs NW arrays. By tuning the catalyst thickness and nucleation and growth temperatures in the two-step chemical vapor deposition, crystalline GaAs NWs with uniform, pure ⟨110⟩ and ⟨111⟩ orientations and other mixture ratios can be successfully prepared. Employing lift-off resists, three-layer NW parallel arrays can be easily attained for X-ray diffraction in order to evaluate their growth orientation along with the fabrication of NW parallel array based Schottky photovoltaic devices for the subsequent performance assessment. Notably, the open-circuit voltage of purely ⟨111⟩-oriented NW arrayed cells is far higher than that of ⟨110⟩-oriented NW arrayed counterparts, which can be interpreted by the different surface Fermi level pinning that exists on various NW crystal surface planes due to the different As dangling bond densities. All this indicates the profound effect of NW crystal orientation on physical and chemical properties of GaAs NWs, suggesting the careful NW design considerations for achieving optimal photovoltaic performances. The approach presented here could also serve as a versatile and powerful platform for in situ characterization of other NW materials.

Multi-arm spectrometer for parallel frequency analysis of radio-wave signals oriented to astronomical observations

NASA Astrophysics Data System (ADS)

Shcherbakov, Alexandre S.; Chavez Dagostino, Miguel; Arellanes, Adan Omar; Tepichin Rodriguez, Eduardo

2017-08-01

We describe a potential prototype of modern spectrometer based on acousto-optical technique with three parallel optical arms for analysis of radio-wave signals specific to astronomical observations. Each optical arm exhibits original performances to provide parallel multi-band observations with different scales simultaneously. Similar multi-band instrument is able to realize measurements within various scenarios from planetary atmospheres to attractive objects in the distant Universe. The arrangement under development has two novelties. First, each optical arm represents an individual spectrum analyzer with its individual performances. Such an approach is conditioned by exploiting various materials for acousto-optical cells operating within various regimes, frequency ranges, and light wavelengths from independent light sources. Individually produced beam shapers give both the needed incident light polarization and the required apodization for light beam to increase the dynamic range of the system as a whole. After parallel acousto-optical processing, a few data flows from these optical arms are united by the joint CCD matrix on the stage of the combined extremely high-bit rate electronic data processing that provides the system performances as well. The other novelty consists in the usage of various materials for designing wide-aperture acousto-optical cells exhibiting the best performances within each of optical arms. Here, one can mention specifically selected cuts of tellurium dioxide, bastron, and lithium niobate, which overlap selected areas within the frequency range from 40 MHz to 2.0 GHz. Thus one yields the united versatile instrument for comprehensive studies of astronomical objects simultaneously with precise synchronization in various frequency ranges.

Micropore extrusion-induced alignment transition from perpendicular to parallel of cylindrical domains in block copolymers.

PubMed

Qu, Ting; Zhao, Yongbin; Li, Zongbo; Wang, Pingping; Cao, Shubo; Xu, Yawei; Li, Yayuan; Chen, Aihua

2016-02-14

The orientation transition from perpendicular to parallel alignment of PEO cylindrical domains of PEO-b-PMA(Az) films has been demonstrated by extruding the block copolymer (BCP) solutions through a micropore of a plastic gastight syringe. The parallelized orientation of PEO domains induced by this micropore extrusion can be recovered to perpendicular alignment via ultrasonication of the extruded BCP solutions and subsequent annealing. A plausible mechanism is proposed in this study. The BCP films can be used as templates to prepare nanowire arrays with controlled layers, which has enormous potential application in the field of integrated circuits.

Applying science and strategy to operating room workforce management.

PubMed

Butler, Victoria; Clinton, Christopher; Sagi, Harsha K; Kenney, Robert; Barsoum, Wael K

2012-01-01

The traditional means of planning nurse staffing for operating rooms are either poorly translated to the setting or do not provide decision makers with a platform to defend their needs, especially in an era of health care reform. The surgical operations department of the Cleveland Clinic initiated a quality improvement project aimed at applying a scientific method to operating room staffing. One goal was to provide a defensible plan for allocating direct caregiver positions. A second goal was to provide a quick and easy way for nurse managers and directors to track positions and graphically depict the effect of vacancies and orientation on their staffing budgets. Using an objective, scientific method allows position requests to be approved quickly and allows managers to feel much more comfortable functioning in a "lean" mode because they know needed positions will be approved quickly. Managers and directors also have found that graphically depicting numbers of vacant positions, as well as staff in orientation, could quickly relate a story visually rather than getting "bogged down" in narrative (often losing finance administrators along the way).

Object-oriented Persistent Homology

PubMed Central

Wang, Bao; Wei, Guo-Wei

2015-01-01

Persistent homology provides a new approach for the topological simplification of big data via measuring the life time of intrinsic topological features in a filtration process and has found its success in scientific and engineering applications. However, such a success is essentially limited to qualitative data classification and analysis. Indeed, persistent homology has rarely been employed for quantitative modeling and prediction. Additionally, the present persistent homology is a passive tool, rather than a proactive technique, for classification and analysis. In this work, we outline a general protocol to construct object-oriented persistent homology methods. By means of differential geometry theory of surfaces, we construct an objective functional, namely, a surface free energy defined on the data of interest. The minimization of the objective functional leads to a Laplace-Beltrami operator which generates a multiscale representation of the initial data and offers an objective oriented filtration process. The resulting differential geometry based object-oriented persistent homology is able to preserve desirable geometric features in the evolutionary filtration and enhances the corresponding topological persistence. The cubical complex based homology algorithm is employed in the present work to be compatible with the Cartesian representation of the Laplace-Beltrami flow. The proposed Laplace-Beltrami flow based persistent homology method is extensively validated. The consistence between Laplace-Beltrami flow based filtration and Euclidean distance based filtration is confirmed on the Vietoris-Rips complex for a large amount of numerical tests. The convergence and reliability of the present Laplace-Beltrami flow based cubical complex filtration approach are analyzed over various spatial and temporal mesh sizes. The Laplace-Beltrami flow based persistent homology approach is utilized to study the intrinsic topology of proteins and fullerene molecules. Based on a quantitative model which correlates the topological persistence of fullerene central cavity with the total curvature energy of the fullerene structure, the proposed method is used for the prediction of fullerene isomer stability. The efficiency and robustness of the present method are verified by more than 500 fullerene molecules. It is shown that the proposed persistent homology based quantitative model offers good predictions of total curvature energies for ten types of fullerene isomers. The present work offers the first example to design object-oriented persistent homology to enhance or preserve desirable features in the original data during the filtration process and then automatically detect or extract the corresponding topological traits from the data. PMID:26705370

Scientific risk communication about controversial issues influences public perceptions of scientists' political orientations and credibility.

PubMed

Vraga, Emily; Myers, Teresa; Kotcher, John; Beall, Lindsey; Maibach, Ed

2018-02-01

Many scientists communicate with the public about risks associated with scientific issues, but such communication may have unintended consequences for how the public views the political orientations and the credibility of the communicating scientist. We explore this possibility using an experiment with a nationally representative sample of Americans in the fall of 2015. We find that risk communication on controversial scientific issues sometimes influences perceptions of the political orientations and credibility of the communicating scientist when the scientist addresses the risks of issues associated with conservative or liberal groups. This relationship is moderated by participant political ideology, with liberals adjusting their perceptions of the scientists' political beliefs more substantially when the scientist addressed the risks of marijuana use when compared with other issues. Conservatives' political perceptions were less impacted by the issue context of the scientific risk communication but indirectly influenced credibility perceptions. Our results support a contextual model of audience interpretation of scientific risk communication. Scientists should be cognizant that audience members may make inferences about the communicating scientist's political orientations and credibility when they engage in risk communication efforts about controversial issues.

ORBS, ORCS, OACS, a Software Suite for Data Reduction and Analysis of the Hyperspectral Imagers SITELLE and SpIOMM

NASA Astrophysics Data System (ADS)

Martin, T.; Drissen, L.; Joncas, G.

2015-09-01

SITELLE (installed in 2015 at the Canada-France-Hawaii Telescope) and SpIOMM (a prototype attached to the Observatoire du Mont-Mégantic) are the first Imaging Fourier Transform Spectrometers (IFTS) capable of obtaining a hyperspectral data cube which samples a 12 arc minutes field of view into four millions of visible spectra. The result of each observation is made up of two interferometric data cubes which need to be merged, corrected, transformed and calibrated in order to get a spectral cube of the observed region ready to be analysed. ORBS is a fully automatic data reduction software that has been entirely designed for this purpose. The data size (up to 68 Gb for larger science cases) and the computational needs have been challenging and the highly parallelized object-oriented architecture of ORBS reflects the solutions adopted which made possible to process 68 Gb of raw data in less than 11 hours using 8 cores and 22.6 Gb of RAM. It is based on a core framework (ORB) that has been designed to support the whole software suite for data analysis (ORCS and OACS), data simulation (ORUS) and data acquisition (IRIS). They all aim to provide a strong basis for the creation and development of specialized analysis modules that could benefit the scientific community working with SITELLE and SpIOMM.

Diderot: a Domain-Specific Language for Portable Parallel Scientific Visualization and Image Analysis.

PubMed

Kindlmann, Gordon; Chiw, Charisee; Seltzer, Nicholas; Samuels, Lamont; Reppy, John

2016-01-01

Many algorithms for scientific visualization and image analysis are rooted in the world of continuous scalar, vector, and tensor fields, but are programmed in low-level languages and libraries that obscure their mathematical foundations. Diderot is a parallel domain-specific language that is designed to bridge this semantic gap by providing the programmer with a high-level, mathematical programming notation that allows direct expression of mathematical concepts in code. Furthermore, Diderot provides parallel performance that takes advantage of modern multicore processors and GPUs. The high-level notation allows a concise and natural expression of the algorithms and the parallelism allows efficient execution on real-world datasets.

Automatic feature-based grouping during multiple object tracking.

PubMed

Erlikhman, Gennady; Keane, Brian P; Mettler, Everett; Horowitz, Todd S; Kellman, Philip J

2013-12-01

Contour interpolation automatically binds targets with distractors to impair multiple object tracking (Keane, Mettler, Tsoi, & Kellman, 2011). Is interpolation special in this regard or can other features produce the same effect? To address this question, we examined the influence of eight features on tracking: color, contrast polarity, orientation, size, shape, depth, interpolation, and a combination (shape, color, size). In each case, subjects tracked 4 of 8 objects that began as undifferentiated shapes, changed features as motion began (to enable grouping), and returned to their undifferentiated states before halting. We found that intertarget grouping improved performance for all feature types except orientation and interpolation (Experiment 1 and Experiment 2). Most importantly, target-distractor grouping impaired performance for color, size, shape, combination, and interpolation. The impairments were, at times, large (>15% decrement in accuracy) and occurred relative to a homogeneous condition in which all objects had the same features at each moment of a trial (Experiment 2), and relative to a "diversity" condition in which targets and distractors had different features at each moment (Experiment 3). We conclude that feature-based grouping occurs for a variety of features besides interpolation, even when irrelevant to task instructions and contrary to the task demands, suggesting that interpolation is not unique in promoting automatic grouping in tracking tasks. Our results also imply that various kinds of features are encoded automatically and in parallel during tracking.

3D Printed, Microgroove Pattern-Driven Generation of Oriented Ligamentous Architectures.

PubMed

Park, Chan Ho; Kim, Kyoung-Hwa; Lee, Yong-Moo; Giannobile, William V; Seol, Yang-Jo

2017-09-08

Specific orientations of regenerated ligaments are crucially required for mechanoresponsive properties and various biomechanical adaptations, which are the key interplay to support mineralized tissues. Although various 2D platforms or 3D printing systems can guide cellular activities or aligned organizations, it remains a challenge to develop ligament-guided, 3D architectures with the angular controllability for parallel, oblique or perpendicular orientations of cells required for biomechanical support of organs. Here, we show the use of scaffold design by additive manufacturing for specific topographies or angulated microgroove patterns to control cell orientations such as parallel (0°), oblique (45°) and perpendicular (90°) angulations. These results demonstrate that ligament cells displayed highly predictable and controllable orientations along microgroove patterns on 3D biopolymeric scaffolds. Our findings demonstrate that 3D printed topographical approaches can regulate spatiotemporal cell organizations that offer strong potential for adaptation to complex tissue defects to regenerate ligament-bone complexes.

The validation by measurement theory of proposed object-oriented software metrics

NASA Technical Reports Server (NTRS)

Neal, Ralph D.

1994-01-01

Moving software development into the engineering arena requires controllability, and to control a process, it must be measurable. Measuring the process does no good if the product is not also measured, i.e., being the best at producing an inferior product does not define a quality process. Also, not every number extracted from software development is a valid measurement. A valid measurement only results when we are able to verify that the number is representative of the attribute that we wish to measure. Many proposed software metrics are used by practitioners without these metrics ever having been validated, leading to costly but often useless calculations. Several researchers have bemoaned the lack of scientific precision in much of the published software measurement work and have called for validation of software metrics by measurement theory. This dissertation applies measurement theory to validate fifty proposed object-oriented software metrics (Li and Henry, 1993; Chidamber and Kemerrer, 1994; Lorenz and Kidd, 1994).

GANDALF - Graphical Astrophysics code for N-body Dynamics And Lagrangian Fluids

NASA Astrophysics Data System (ADS)

Hubber, D. A.; Rosotti, G. P.; Booth, R. A.

2018-01-01

GANDALF is a new hydrodynamics and N-body dynamics code designed for investigating planet formation, star formation and star cluster problems. GANDALF is written in C++, parallelized with both OPENMP and MPI and contains a PYTHON library for analysis and visualization. The code has been written with a fully object-oriented approach to easily allow user-defined implementations of physics modules or other algorithms. The code currently contains implementations of smoothed particle hydrodynamics, meshless finite-volume and collisional N-body schemes, but can easily be adapted to include additional particle schemes. We present in this paper the details of its implementation, results from the test suite, serial and parallel performance results and discuss the planned future development. The code is freely available as an open source project on the code-hosting website github at https://github.com/gandalfcode/gandalf and is available under the GPLv2 license.

Implementation and Assessment of a Virtual Laboratory of Parallel Robots Developed for Engineering Students

ERIC Educational Resources Information Center

Gil, Arturo; Peidró, Adrián; Reinoso, Óscar; Marín, José María

2017-01-01

This paper presents a tool, LABEL, oriented to the teaching of parallel robotics. The application, organized as a set of tools developed using Easy Java Simulations, enables the study of the kinematics of parallel robotics. A set of classical parallel structures was implemented such that LABEL can solve the inverse and direct kinematic problem of…

Anisotropy in Third-Order Nonlinear Optical Susceptibility of a Squarylium Dye in a Nematic Liquid Crystal

NASA Astrophysics Data System (ADS)

Jin, Zhao-Hui; Li, Zhong-Yu; Kasatani, Kazuo; Okamoto, Hiroaki

2006-03-01

A squarylium dye is dissolved in 4-cyano-4'-pentylbiphenyl (5CB) and oriented by sandwiching mixtures between two pieces of rubbed glass plates. The optical absorption spectra of the oriented squarylium dye-5CB layers exhibit high anisotropy. The third-order nonlinear optical responses and susceptibilities χ(3)e of squarylium dye in 5CB are measured with light polarizations parallel and perpendicular to the orientational direction by the resonant femtosecond degenerate four-wave mixing (DFWM) technique. Temporal profiles of the DFWM signal of the oriented squarylium dye-5CB layers with light polarizations parallel and perpendicular to the orientational direction are measured with a time resolution of 0.3 ps (FWHM), and are found to consist of two components, i.e., the coherent instantaneous nonlinear response and slow response due to the formation of excited molecules. A high anisotropic ratio of χ(3)e, 10.8±1.2, is observed for the oriented layers.

Smartfiles: An OO approach to data file interoperability

NASA Technical Reports Server (NTRS)

Haines, Matthew; Mehrotra, Piyush; Vanrosendale, John

1995-01-01

Data files for scientific and engineering codes typically consist of a series of raw data values whose descriptions are buried in the programs that interact with these files. In this situation, making even minor changes in the file structure or sharing files between programs (interoperability) can only be done after careful examination of the data file and the I/O statement of the programs interacting with this file. In short, scientific data files lack self-description, and other self-describing data techniques are not always appropriate or useful for scientific data files. By applying an object-oriented methodology to data files, we can add the intelligence required to improve data interoperability and provide an elegant mechanism for supporting complex, evolving, or multidisciplinary applications, while still supporting legacy codes. As a result, scientists and engineers should be able to share datasets with far greater ease, simplifying multidisciplinary applications and greatly facilitating remote collaboration between scientists.

An analysis of 12th-grade students' reasoning styles and competencies when presented with an environmental problem in a social and scientific context

NASA Astrophysics Data System (ADS)

Yang, Fang-Ying

This study examined reasoning and problem solving by 182 12th grade students in Taiwan when considering a socio-scientific issue regarding the use of nuclear energy. Students' information preferences, background characteristics, and eleven everyday scientific thinking skills were scrutinized. It was found most participants displayed a willingness to take into account both scientific and social information in reasoning the merits of a proposed construction of a nuclear power plant. Students' reasoning scores obtained from the "information reasoning style" test ranged from -0.5 to 1.917. And, the distribution was approximately normal with mean and median at around 0.5. For the purpose of categorization, students whose scores were within one standard deviation from the mean were characterized as having a "equally disposed" reasoning style. One hundred and twenty-five subjects, about 69%, belonged to this category. Students with scores locating at the two tails of the distribution were assigned to either the "scientifically oriented" or the "socially oriented" reasoning category. Among 23 background characteristics investigated using questionnaire data and ANOVA statistical analysis, only students' science performance and knowledge about nuclear energy were statistically significantly related to their information reasoning styles (p < 0.05). The assessed background characteristics addressed dimensions such as gender, academic performances, class difference, future education, career expectation, commitment to study, assessment to educational enrichment, family conditions, epistemological views about science, religion, and the political party preference. For everyday scientific thinking skills, interview data showed that both "scientifically oriented" students and those who were categorized as "equally disposed to using scientific and social scientific sources of data" displayed higher frequencies than "socially oriented" ones in using these skills, except in the use of the "multidisciplinary thinking" skill. Among the 11 skills assessed, the "scientifically oriented" students outperformed the "equally disposed" ones only in the use of 3 thinking skills; namely, searching for or recalling scientific concepts/evidence, recognizing and evaluating alternatives, and making conclusions based on the scientific intuition.

Highly parallel computation

NASA Technical Reports Server (NTRS)

Denning, Peter J.; Tichy, Walter F.

1990-01-01

Highly parallel computing architectures are the only means to achieve the computation rates demanded by advanced scientific problems. A decade of research has demonstrated the feasibility of such machines and current research focuses on which architectures designated as multiple instruction multiple datastream (MIMD) and single instruction multiple datastream (SIMD) have produced the best results to date; neither shows a decisive advantage for most near-homogeneous scientific problems. For scientific problems with many dissimilar parts, more speculative architectures such as neural networks or data flow may be needed.

Orientation of ripples induced by ultrafast laser pulses on copper in different liquids

NASA Astrophysics Data System (ADS)

Maragkaki, Stella; Elkalash, Abdallah; Gurevich, Evgeny L.

2017-12-01

Formation of laser-induced periodic surface structures (LIPSS or ripples) was studied on a metallic surface of polished copper using irradiation with multiple femtosecond laser pulses in different environmental conditions (air, water, ethanol and methanol). Uniform LIPSS have been achieved by controlling the peak fluence and the overlapping rate. Ripples in both orientations, perpendicular and parallel to laser polarization, were observed in all liquids simultaneously. The orientation of these ripples in the center of the ablated line was changing with the incident light intensity. For low intensities the orientation of the ripples is perpendicular to the laser polarization, whereas for high intensities it turns parallel to it without considerable changes in the period. Multi-directional LIPSS formation was also observed for moderate peak fluence in liquid environments.

Multi-objective ACO algorithms to minimise the makespan and the total rejection cost on BPMs with arbitrary job weights

NASA Astrophysics Data System (ADS)

Jia, Zhao-hong; Pei, Ming-li; Leung, Joseph Y.-T.

2017-12-01

In this paper, we investigate the batch-scheduling problem with rejection on parallel machines with non-identical job sizes and arbitrary job-rejected weights. If a job is rejected, the corresponding penalty has to be paid. Our objective is to minimise the makespan of the processed jobs and the total rejection cost of the rejected jobs. Based on the selected multi-objective optimisation approaches, two problems, P1 and P2, are considered. In P1, the two objectives are linearly combined into one single objective. In P2, the two objectives are simultaneously minimised and the Pareto non-dominated solution set is to be found. Based on the ant colony optimisation (ACO), two algorithms, called LACO and PACO, are proposed to address the two problems, respectively. Two different objective-oriented pheromone matrices and heuristic information are designed. Additionally, a local optimisation algorithm is adopted to improve the solution quality. Finally, simulated experiments are conducted, and the comparative results verify the effectiveness and efficiency of the proposed algorithms, especially on large-scale instances.

Conceptual Teaching Based on Scientific Storyline Method and Conceptual Change Texts: Latitude-Parallel Concepts

ERIC Educational Resources Information Center

Uzunöz, Abdulkadir

2018-01-01

The purpose of this study is to identify the conceptual mistakes frequently encountered in teaching geography such as latitude-parallel concepts, and to prepare conceptual change text based on the Scientific Storyline Method, in order to resolve the identified misconceptions. In this study, the special case method, which is one of the qualitative…

Parallel object-oriented, denoising system using wavelet multiresolution analysis

DOEpatents

Kamath, Chandrika; Baldwin, Chuck H.; Fodor, Imola K.; Tang, Nu A.

2005-04-12

The present invention provides a data de-noising system utilizing processors and wavelet denoising techniques. Data is read and displayed in different formats. The data is partitioned into regions and the regions are distributed onto the processors. Communication requirements are determined among the processors according to the wavelet denoising technique and the partitioning of the data. The data is transforming onto different multiresolution levels with the wavelet transform according to the wavelet denoising technique, the communication requirements, and the transformed data containing wavelet coefficients. The denoised data is then transformed into its original reading and displaying data format.

Linear dichroism of DNA: Characterization of the orientation distribution function caused by hydrodynamic shear

DOE PAGES

Sutherland, John C.

2017-04-15

Linear dichroism provides information on the orientation of chromophores part of, or bound to, an orientable molecule such as DNA. For molecular alignment induced by hydrodynamic shear, the principal axes orthogonal to the direction of alignment are not equivalent. Thus, the magnitude of the flow-induced change in absorption for light polarized parallel to the direction of flow can be more than a factor of two greater than the corresponding change for light polarized perpendicular to both that direction and the shear axis. The ratio of the two flow-induced changes in absorption, the dichroic increment ratio, is characterized using the orthogonalmore » orientation model, which assumes that each absorbing unit is aligned parallel to one of the principal axes of the apparatus. The absorption of the alienable molecules is characterized by components parallel and perpendicular to the orientable axis of the molecule. The dichroic increment ratio indicates that for the alignment of DNA in rectangular flow cells, average alignment is not uniaxial, but for higher shear, as produced in a Couette cell, it can be. The results from the simple model are identical to tensor models for typical experimental configuration. Approaches for measuring the dichroic increment ratio with modern dichrometers are further discussed.« less

Linear dichroism of DNA: Characterization of the orientation distribution function caused by hydrodynamic shear

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sutherland, John C.

Linear dichroism provides information on the orientation of chromophores part of, or bound to, an orientable molecule such as DNA. For molecular alignment induced by hydrodynamic shear, the principal axes orthogonal to the direction of alignment are not equivalent. Thus, the magnitude of the flow-induced change in absorption for light polarized parallel to the direction of flow can be more than a factor of two greater than the corresponding change for light polarized perpendicular to both that direction and the shear axis. The ratio of the two flow-induced changes in absorption, the dichroic increment ratio, is characterized using the orthogonalmore » orientation model, which assumes that each absorbing unit is aligned parallel to one of the principal axes of the apparatus. The absorption of the alienable molecules is characterized by components parallel and perpendicular to the orientable axis of the molecule. The dichroic increment ratio indicates that for the alignment of DNA in rectangular flow cells, average alignment is not uniaxial, but for higher shear, as produced in a Couette cell, it can be. The results from the simple model are identical to tensor models for typical experimental configuration. Approaches for measuring the dichroic increment ratio with modern dichrometers are further discussed.« less

Linear dichroism of DNA: Characterization of the orientation distribution function caused by hydrodynamic shear.

PubMed

Sutherland, John C

2017-04-15

Linear dichroism provides information on the orientation of chromophores part of, or bound to, an orientable molecule such as DNA. For molecular alignment induced by hydrodynamic shear, the principal axes orthogonal to the direction of alignment are not equivalent. Thus, the magnitude of the flow-induced change in absorption for light polarized parallel to the direction of flow can be more than a factor of two greater than the corresponding change for light polarized perpendicular to both that direction and the shear axis. The ratio of the two flow-induced changes in absorption, the dichroic increment ratio, is characterized using the orthogonal orientation model, which assumes that each absorbing unit is aligned parallel to one of the principal axes of the apparatus. The absorption of the alienable molecules is characterized by components parallel and perpendicular to the orientable axis of the molecule. The dichroic increment ratio indicates that for the alignment of DNA in rectangular flow cells, average alignment is not uniaxial, but for higher shear, as produced in a Couette cell, it can be. The results from the simple model are identical to tensor models for typical experimental configurations. Approaches for measuring the dichroic increment ratio with modern dichrometers are discussed. Copyright © 2017. Published by Elsevier Inc.

Raman technology for future planetary missions

NASA Astrophysics Data System (ADS)

Thiele, Hans; Hofer, Stefan; Stuffler, Timo; Glier, Markus; Popp, Jürgen; Sqalli, Omar; Wuttig, Andreas; Riesenberg, Rainer

2017-11-01

Scientific experiments on mineral and biological samples with Raman excitation below 300nm show a wealth of scientific information. The fluorescence, which typically decreases signal quality in the visual or near infrared wavelength regime can be avoided with deep ultraviolet excitation. This wavelength regime is therefore regarded as highly attractive for a compact high performance Raman spectrometer for in-situ planetary research. Main objective of the MIRAS II breadboard activity presented here (MIRAS: Mineral Investigation with Raman Spectroscopy) is to evaluate, design and build a compact fiber coupled deep-UV Raman system breadboard. Additionally, the Raman system is combined with an innovative scanning microscope system to allow effective auto-focusing and autonomous orientation on the sample surface for high precise positioning or high resolution Raman mapping.

Adapter plate assembly for adjustable mounting of objects

DOEpatents

Blackburn, R.S.

1986-05-02

An adapter plate and two locking discs are together affixed to an optic table with machine screws or bolts threaded into a fixed array of internally threaded holes provided in the table surface. The adapter plate preferably has two, and preferably parallel, elongated locating slots each freely receiving a portion of one of the locking discs for secure affixation of the adapter plate to the optic table. A plurality of threaded apertures provided in the adapter plate are available to attach optical mounts or other devices onto the adapter plate in an orientation not limited by the disposition of the array of threaded holes in the table surface. An axially aligned but radially offset hole through each locking disc receives a screw that tightens onto the table, such that prior to tightening of the screw the locking disc may rotate and translate within each locating slot of the adapter plate for maximum flexibility of the orientation thereof.

Adapter plate assembly for adjustable mounting of objects

DOEpatents

Blackburn, Robert S.

1987-01-01

An adapter plate and two locking discs are together affixed to an optic table with machine screws or bolts threaded into a fixed array of internally threaded holes provided in the table surface. The adapter plate preferably has two, and preferably parallel, elongated locating slots each freely receiving a portion of one of the locking discs for secure affixation of the adapter plate to the optic table. A plurality of threaded apertures provided in the adapter plate are available to attach optical mounts or other devices onto the adapter plate in an orientation not limited by the disposition of the array of threaded holes in the table surface. An axially aligned but radially offset hole through each locking disc receives a screw that tightens onto the table, such that prior to tightening of the screw the locking disc may rotate and translate within each locating slot of the adapter plate for maximum flexibility of the orientation thereof.

Increased Sensitivity to Mirror Symmetry in Autism

PubMed Central

Perreault, Audrey; Gurnsey, Rick; Dawson, Michelle; Mottron, Laurent; Bertone, Armando

2011-01-01

Can autistic people see the forest for the trees? Ongoing uncertainty about the integrity and role of global processing in autism gives special importance to the question of how autistic individuals group local stimulus attributes into meaningful spatial patterns. We investigated visual grouping in autism by measuring sensitivity to mirror symmetry, a highly-salient perceptual image attribute preceding object recognition. Autistic and non-autistic individuals were asked to detect mirror symmetry oriented along vertical, oblique, and horizontal axes. Both groups performed best when the axis was vertical, but across all randomly-presented axis orientations, autistics were significantly more sensitive to symmetry than non-autistics. We suggest that under some circumstances, autistic individuals can take advantage of parallel access to local and global information. In other words, autistics may sometimes see the forest and the trees, and may therefore extract from noisy environments genuine regularities which elude non-autistic observers. PMID:21559337

Parallel tempering Monte Carlo simulations of lysozyme orientation on charged surfaces

NASA Astrophysics Data System (ADS)

Xie, Yun; Zhou, Jian; Jiang, Shaoyi

2010-02-01

In this work, the parallel tempering Monte Carlo (PTMC) algorithm is applied to accurately and efficiently identify the global-minimum-energy orientation of a protein adsorbed on a surface in a single simulation. When applying the PTMC method to simulate lysozyme orientation on charged surfaces, it is found that lysozyme could easily be adsorbed on negatively charged surfaces with "side-on" and "back-on" orientations. When driven by dominant electrostatic interactions, lysozyme tends to be adsorbed on negatively charged surfaces with the side-on orientation for which the active site of lysozyme faces sideways. The side-on orientation agrees well with the experimental results where the adsorbed orientation of lysozyme is determined by electrostatic interactions. As the contribution from van der Waals interactions gradually dominates, the back-on orientation becomes the preferred one. For this orientation, the active site of lysozyme faces outward, which conforms to the experimental results where the orientation of adsorbed lysozyme is co-determined by electrostatic interactions and van der Waals interactions. It is also found that despite of its net positive charge, lysozyme could be adsorbed on positively charged surfaces with both "end-on" and back-on orientations owing to the nonuniform charge distribution over lysozyme surface and the screening effect from ions in solution. The PTMC simulation method provides a way to determine the preferred orientation of proteins on surfaces for biosensor and biomaterial applications.

The Galley Parallel File System

NASA Technical Reports Server (NTRS)

Nieuwejaar, Nils; Kotz, David

1996-01-01

Most current multiprocessor file systems are designed to use multiple disks in parallel, using the high aggregate bandwidth to meet the growing I/0 requirements of parallel scientific applications. Many multiprocessor file systems provide applications with a conventional Unix-like interface, allowing the application to access multiple disks transparently. This interface conceals the parallelism within the file system, increasing the ease of programmability, but making it difficult or impossible for sophisticated programmers and libraries to use knowledge about their I/O needs to exploit that parallelism. In addition to providing an insufficient interface, most current multiprocessor file systems are optimized for a different workload than they are being asked to support. We introduce Galley, a new parallel file system that is intended to efficiently support realistic scientific multiprocessor workloads. We discuss Galley's file structure and application interface, as well as the performance advantages offered by that interface.

Cross-polarised and parallel-polarised light: Viewing and photography for examination and documentation of biological materials in medicine and forensics.

PubMed

Hanlon, Katharine L

2018-01-01

Cross-polarisation, with regard to visible light, is a process wherein two polarisers with perpendicular orientation to one another are used on the incident and reflected lights. Under cross-polarised light birefringent structures which are otherwise invisible become apparent. Cross-polarised light eliminates glare and specular highlights, allowing for an unobstructed view of subsurface pathology. Parallel-polarisation occurs when the polarisers are rotated to the same orientation. When cross- or parallel-polarisation is applied to photography, images can be generated which aid in visualisation of surface and subsurface elements. Improved access to equipment and education has the potential to benefit practitioners, researchers, investigators and patients.

Enhancing Interactivity and Productivity through Object-Oriented Authoring: An Instructional Designer's Perspective.

ERIC Educational Resources Information Center

Chapman, Bryan L.

1994-01-01

Discusses the effect of object-oriented programming on the evolution of authoring systems. Topics include the definition of an object; examples of object-oriented authoring interfaces; what object-orientation means to an instructional developer; how object orientation increases productivity and enhances interactivity; and the future of courseware…

The Parallelism between Scientists' and Students' Resistance to New Scientific Ideas.

ERIC Educational Resources Information Center

Campanario, Juan Miguel

2002-01-01

Compares resistance by scientists to new ideas in scientific discovery with students' resistance to conceptual change in scientific learning. Studies the resistance by students to abandoning their misconceptions concerning scientific topics and the resistance by scientists to scientific discovery. (Contains 64 references.) (Author/YDS)

Survival distributions impact the power of randomized placebo-phase design and parallel groups randomized clinical trials.

PubMed

Abrahamyan, Lusine; Li, Chuan Silvia; Beyene, Joseph; Willan, Andrew R; Feldman, Brian M

2011-03-01

The study evaluated the power of the randomized placebo-phase design (RPPD)-a new design of randomized clinical trials (RCTs), compared with the traditional parallel groups design, assuming various response time distributions. In the RPPD, at some point, all subjects receive the experimental therapy, and the exposure to placebo is for only a short fixed period of time. For the study, an object-oriented simulation program was written in R. The power of the simulated trials was evaluated using six scenarios, where the treatment response times followed the exponential, Weibull, or lognormal distributions. The median response time was assumed to be 355 days for the placebo and 42 days for the experimental drug. Based on the simulation results, the sample size requirements to achieve the same level of power were different under different response time to treatment distributions. The scenario where the response times followed the exponential distribution had the highest sample size requirement. In most scenarios, the parallel groups RCT had higher power compared with the RPPD. The sample size requirement varies depending on the underlying hazard distribution. The RPPD requires more subjects to achieve a similar power to the parallel groups design. Copyright © 2011 Elsevier Inc. All rights reserved.

An exploration for research-oriented teaching model in biology teaching.

PubMed

Xing, Wanjin; Mo, Morigen; Su, Huimin

2014-07-01

Training innovative talents, as one of the major aims for Chinese universities, needs to reform the traditional teaching methods. The research-oriented teaching method has been introduced and its connotation and significance for Chinese university teaching have been discussed for years. However, few practical teaching methods for routine class teaching were proposed. In this paper, a comprehensive and concrete research-oriented teaching model with contents of reference value and evaluation method for class teaching was proposed based on the current teacher-guiding teaching model in China. We proposed that the research-oriented teaching model should include at least seven aspects on: (1) telling the scientific history for the skills to find out scientific questions; (2) replaying the experiments for the skills to solve scientific problems; (3) analyzing experimental data for learning how to draw a conclusion; (4) designing virtual experiments for learning how to construct a proposal; (5) teaching the lesson as the detectives solve the crime for learning the logic in scientific exploration; (6) guiding students how to read and consult the relative references; (7) teaching students differently according to their aptitude and learning ability. In addition, we also discussed how to evaluate the effects of the research-oriented teaching model in examination.

Parallel heater system for subsurface formations

DOEpatents

Harris, Christopher Kelvin [Houston, TX; Karanikas, John Michael [Houston, TX; Nguyen, Scott Vinh [Houston, TX

2011-10-25

A heating system for a subsurface formation is disclosed. The system includes a plurality of substantially horizontally oriented or inclined heater sections located in a hydrocarbon containing layer in the formation. At least a portion of two of the heater sections are substantially parallel to each other. The ends of at least two of the heater sections in the layer are electrically coupled to a substantially horizontal, or inclined, electrical conductor oriented substantially perpendicular to the ends of the at least two heater sections.

A high-performance model for shallow-water simulations in distributed and heterogeneous architectures

NASA Astrophysics Data System (ADS)

Conde, Daniel; Canelas, Ricardo B.; Ferreira, Rui M. L.

2017-04-01

One of the most common challenges in hydrodynamic modelling is the trade off one must make between highly resolved simulations and the time required for their computation. In the particular case of urban floods, modelers are often forced to simplify the complex geometries of the problem, or to implicitly include some of its hydrodynamic effects, due to the typically very large spatial scales involved and limited computational resources. At CEris - Instituto Superior Técnico, Universidade de Lisboa - the STAV-2D shallow-water model, particularly suited for strong transient flows in complex and dynamic geometries, has been under development for the past recent years (Canelas et al., 2013 & Conde et al., 2013). The model is based on an explicit, first-order 2DH finite-volume discretization scheme for unstructured triangular meshes, in which a flux-splitting technique is paired with a reviewed Roe-Riemann solver, yielding a model applicable to discontinuous flows over time-evolving geometries. STAV-2D features solid transport in both Euleran and Lagrangian forms, with the first aiming at describing the transport of fine natural sediments and the latter aimed at large individual debris. The model has been validated with theoretical solutions and laboratory experiments (Canelas et al., 2013 & Conde et al., 2015). This work presents our most recent effort in STAV-2D: the re-design of the code in a modern Object-Oriented parallel framework for heterogeneous computations in CPUs and GPUs. The programming language of choice for this re-design was C++, due to its wide support of established and emerging parallel programming interfaces. The current implementation of STAV-2D provides two different levels of parallel granularity: inter-node and intra-node. Inter-node parallelism is achieved by distributing a simulation across a set of worker nodes, with communication between nodes being explicitly managed through MPI. At this level, the main difficulty is associated with the unstructured nature of the mesh topology with the corresponding employed solution, based on space-filling curves, being analyzed and discussed. Intra-node parallelism is achieved through OpenMP for CPUs and CUDA for GPUs, depending on which kind of device the process is running. Here the main difficulty is associated with the Object-Oriented approach, where the presence of complex data structures can degrade model performance considerably. STAV-2D now supports fully distributed and heterogeneous simulations where multiple different devices can be used to accelerate computation time. The advantages, short-comings and specific solutions for the employed unified Object-Oriented approach, where the source code for CPU and GPU has the same compilation units (no device specific branches like seen in available models), are discussed and quantified with a thorough scalability and performance analysis. The assembled parallel model is expected to achieve faster than real-time simulations for high resolutions (from meters to sub-meter) in large scaled problems (from cities to watersheds), effectively bridging the gap between detailed and timely simulation results. Acknowledgements This research as partially supported by Portuguese and European funds, within programs COMPETE2020 and PORL-FEDER, through project PTDC/ECM-HID/6387/2014 and Doctoral Grant SFRH/BD/97933/2013 granted by the National Foundation for Science and Technology (FCT). References Canelas, R.; Murillo, J. & Ferreira, R.M.L. (2013), Two-dimensional depth-averaged modelling of dam-break flows over mobile beds. Journal of Hydraulic Research, 51(4), 392-407. Conde, D. A. S.; Baptista, M. A. V.; Sousa Oliveira, C. & Ferreira, R. M. L. (2013), A shallow-flow model for the propagation of tsunamis over complex geometries and mobile beds, Nat. Hazards and Earth Syst. Sci., 13, 2533-2542. Conde, D. A. S.; Telhado, M. J.; Viana Baptista, M. A. & Ferreira, R. M. L. (2015) Severity and exposure associated with tsunami actions in urban waterfronts: the case of Lisbon, Portugal. Natural Hazards, Springer, 79, 2125, DOI:10.1007/s11069-015-1951-z

OFF, Open source Finite volume Fluid dynamics code: A free, high-order solver based on parallel, modular, object-oriented Fortran API

NASA Astrophysics Data System (ADS)

Zaghi, S.

2014-07-01

OFF, an open source (free software) code for performing fluid dynamics simulations, is presented. The aim of OFF is to solve, numerically, the unsteady (and steady) compressible Navier-Stokes equations of fluid dynamics by means of finite volume techniques: the research background is mainly focused on high-order (WENO) schemes for multi-fluids, multi-phase flows over complex geometries. To this purpose a highly modular, object-oriented application program interface (API) has been developed. In particular, the concepts of data encapsulation and inheritance available within Fortran language (from standard 2003) have been stressed in order to represent each fluid dynamics "entity" (e.g. the conservative variables of a finite volume, its geometry, etc…) by a single object so that a large variety of computational libraries can be easily (and efficiently) developed upon these objects. The main features of OFF can be summarized as follows: Programming LanguageOFF is written in standard (compliant) Fortran 2003; its design is highly modular in order to enhance simplicity of use and maintenance without compromising the efficiency; Parallel Frameworks Supported the development of OFF has been also targeted to maximize the computational efficiency: the code is designed to run on shared-memory multi-cores workstations and distributed-memory clusters of shared-memory nodes (supercomputers); the code's parallelization is based on Open Multiprocessing (OpenMP) and Message Passing Interface (MPI) paradigms; Usability, Maintenance and Enhancement in order to improve the usability, maintenance and enhancement of the code also the documentation has been carefully taken into account; the documentation is built upon comprehensive comments placed directly into the source files (no external documentation files needed): these comments are parsed by means of doxygen free software producing high quality html and latex documentation pages; the distributed versioning system referred as git has been adopted in order to facilitate the collaborative maintenance and improvement of the code; CopyrightsOFF is a free software that anyone can use, copy, distribute, study, change and improve under the GNU Public License version 3. The present paper is a manifesto of OFF code and presents the currently implemented features and ongoing developments. This work is focused on the computational techniques adopted and a detailed description of the main API characteristics is reported. OFF capabilities are demonstrated by means of one and two dimensional examples and a three dimensional real application.

[An approach to a methodology of scientific research for assistant-students].

PubMed

Novak, Ivón T C; Bejarano, Paola Antón; Rodríguez, Fernando Marcos

2007-01-01

This work is presented from a "problematic" perspective in the attempt to establish a dialogic relationship between the educator and the student-subject, mediated by the object of knowledge. It is oriented to the integral education of the helping students departing from a closer approach to the scientific research. This work was carried out by a teacher and two hired students. This project was developed in relation with the profile required for the career of medicine in the Faculty of Medicine of the National University of Cordoba which--among other aspects- addresses the importance of "adopting a positive attitude towards research based on knowledge and the application of the scientific methodology" and towards "the development of a responsible self-learning and continuous improvements" (sic). Thus, this work tries to be aligned with this perspectives. I. Characterization of the scientific methodology. Search for bibliography and discussion of scientific works. II. Optimization of the methodology for the observation of leucocytes: blood samples donated by healthy people, non-coagulating with citrate or with EDTA (Blood reservoir of the UNC (National University of Cordoba) n = 20. a) Blood smear of full blood. b) centrifugation at 200g of plasma and aspirated leucocytes after erythro sedimentation and re suspension of the cell pellet and cyto-dispersion. Cytological and cyto-chemical techniques. I. Deeper knowledge about blood field was achieved. It generated an appropriate atmosphere to produce scientific questioning and the activities involved in the process were carried out responsibly. II. Better results were achieved using EDTA for the observation and analysis of leucocytes. It was possible to attain the objectives for an approach to a scientific research as well as for a contribution towards a responsible development in the continuous learning process.

Automation of multi-agent control for complex dynamic systems in heterogeneous computational network

NASA Astrophysics Data System (ADS)

Oparin, Gennady; Feoktistov, Alexander; Bogdanova, Vera; Sidorov, Ivan

2017-01-01

The rapid progress of high-performance computing entails new challenges related to solving large scientific problems for various subject domains in a heterogeneous distributed computing environment (e.g., a network, Grid system, or Cloud infrastructure). The specialists in the field of parallel and distributed computing give the special attention to a scalability of applications for problem solving. An effective management of the scalable application in the heterogeneous distributed computing environment is still a non-trivial issue. Control systems that operate in networks, especially relate to this issue. We propose a new approach to the multi-agent management for the scalable applications in the heterogeneous computational network. The fundamentals of our approach are the integrated use of conceptual programming, simulation modeling, network monitoring, multi-agent management, and service-oriented programming. We developed a special framework for an automation of the problem solving. Advantages of the proposed approach are demonstrated on the parametric synthesis example of the static linear regulator for complex dynamic systems. Benefits of the scalable application for solving this problem include automation of the multi-agent control for the systems in a parallel mode with various degrees of its detailed elaboration.

Scientific risk communication about controversial issues influences public perceptions of scientists' political orientations and credibility

PubMed Central

2018-01-01

Many scientists communicate with the public about risks associated with scientific issues, but such communication may have unintended consequences for how the public views the political orientations and the credibility of the communicating scientist. We explore this possibility using an experiment with a nationally representative sample of Americans in the fall of 2015. We find that risk communication on controversial scientific issues sometimes influences perceptions of the political orientations and credibility of the communicating scientist when the scientist addresses the risks of issues associated with conservative or liberal groups. This relationship is moderated by participant political ideology, with liberals adjusting their perceptions of the scientists' political beliefs more substantially when the scientist addressed the risks of marijuana use when compared with other issues. Conservatives' political perceptions were less impacted by the issue context of the scientific risk communication but indirectly influenced credibility perceptions. Our results support a contextual model of audience interpretation of scientific risk communication. Scientists should be cognizant that audience members may make inferences about the communicating scientist's political orientations and credibility when they engage in risk communication efforts about controversial issues. PMID:29515820

Formation of organic layer on femtosecond laser-induced periodic surface structures

NASA Astrophysics Data System (ADS)

Yasumaru, Naoki; Sentoku, Eisuke; Kiuchi, Junsuke

2017-05-01

Two types of laser-induced periodic surface structures (LIPSS) formed on titanium by femtosecond (fs) laser pulses (λ = 800 nm, τ = 180 fs, ν = 1 kHz) in air were investigated experimentally. At a laser fluence F above the ablation threshold, LIPSS with a minimum mean spacing of D < λ⁄2 were observed perpendicular to the laser polarization direction. In contrast, for F slightly below than the ablation threshold, ultrafine LIPSS with a minimum value of D < λ/10 were formed parallel to the polarization direction. The surface roughness of the parallel-oriented LIPSS was almost the same as that of the non-irradiated surface, unlike the high roughness of the perpendicular-oriented LIPSS. In addition, although the surface state of the parallel-oriented LIPSS was the same as that of the non-irradiated surface, the perpendicular-oriented LIPSS were covered with an organic thin film similar to a cellulose derivative that cannot be easily formed by conventional chemical synthesis. The results of these surface analyses indicate that these two types of LIPSS are formed through different mechanisms. This fs-laser processing technique may become a new technology for the artificial synthesis of cellulose derivatives.

Publishing Platform for Scientific Software - Lessons Learned

NASA Astrophysics Data System (ADS)

Hammitzsch, Martin; Fritzsch, Bernadette; Reusser, Dominik; Brembs, Björn; Deinzer, Gernot; Loewe, Peter; Fenner, Martin; van Edig, Xenia; Bertelmann, Roland; Pampel, Heinz; Klump, Jens; Wächter, Joachim

2015-04-01

Scientific software has become an indispensable commodity for the production, processing and analysis of empirical data but also for modelling and simulation of complex processes. Software has a significant influence on the quality of research results. For strengthening the recognition of the academic performance of scientific software development, for increasing its visibility and for promoting the reproducibility of research results, concepts for the publication of scientific software have to be developed, tested, evaluated, and then transferred into operations. For this, the publication and citability of scientific software have to fulfil scientific criteria by means of defined processes and the use of persistent identifiers, similar to data publications. The SciForge project is addressing these challenges. Based on interviews a blueprint for a scientific software publishing platform and a systematic implementation plan has been designed. In addition, the potential of journals, software repositories and persistent identifiers have been evaluated to improve the publication and dissemination of reusable software solutions. It is important that procedures for publishing software as well as methods and tools for software engineering are reflected in the architecture of the platform, in order to improve the quality of the software and the results of research. In addition, it is necessary to work continuously on improving specific conditions that promote the adoption and sustainable utilization of scientific software publications. Among others, this would include policies for the development and publication of scientific software in the institutions but also policies for establishing the necessary competencies and skills of scientists and IT personnel. To implement the concepts developed in SciForge a combined bottom-up / top-down approach is considered that will be implemented in parallel in different scientific domains, e.g. in earth sciences, climate research and the life sciences. Based on the developed blueprints a scientific software publishing platform will be iteratively implemented, tested, and evaluated. Thus the platform should be developed continuously on the basis of gained experiences and results. The platform services will be extended one by one corresponding to the requirements of the communities. Thus the implemented platform for the publication of scientific software can be improved and stabilized incrementally as a tool with software, science, publishing, and user oriented features.

Fracture Anisotropy and Toughness in the Mancos Shale: Implications for crack-growth geometry

NASA Astrophysics Data System (ADS)

Chandler, M. R.; Meredith, P. G.; Brantut, N.; Crawford, B. R.

2013-12-01

The hydraulic fracturing of gas-shales has drawn attention to the fundamental fracture properties of shales. Fracture propagation is dependent on a combination of the in-situ stress field, the fracturing fluid and pressure, and the mechanical properties of the shale. However, shales are strongly anisotropic, and there is a general paucity of available experimental data on the anisotropic mechanical properties of shales in the scientific literature. The mode-I stress intensity factor, KI, quantifies the concentration of stress at crack tips. The Fracture Toughness of a linear elastic material is then defined as the critical value of this stress intensity factor; KIc, beyond which rapid catastrophic crack growth occurs. However, shales display significant non-linearity, which produces hysteresis during experimental cyclic loading. This allows for the calculation of a ductility coefficient using the residual displacement after successive loading cycles. From this coefficient, a ductility corrected Fracture Toughness value, KIcc can be determined. In the Mancos Shale this ductility correction can be as large as 60%, giving a Divider orientation KIcc value of 0.8 MPa.m0.5. Tensile strength and mode-I Fracture Toughness have been experimentally determined for the Mancos Shale using the Brazil Disk and Short-Rod methodologies respectively. The three principal fracture orientations; Arrester, Divider and Short-Transverse were all analysed. A significant anisotropy is observed in the tensile strength, with the Arrester value being 1.5 times higher than the Short-Transverse value. Even larger anisotropy is observed in the Fracture Toughness, with KIcc in the Divider and Arrester orientations being around 1.8 times that in the Short-Transverse orientation. For both tensile strength and fracture toughness, the Short-Transverse orientation, where the fracture propagates in the bedding plane in a direction parallel to the bedding, is found to have significantly lower values than the other two orientations. This anisotropy and variability in fracture properties is seen to cause deviation of the fracture direction during experiments on Arrester and Short-Transverse oriented samples, and can be expected to influence the geometry of propagating fractures. A comparison between the anisotropic tensile strength of the material and the crack-tip stress field in a transversely isotropic material has been used to develop a crack-tip deflection criterion in terms of the elasticity theory of cracks. This criterion suggests that a small perturbation in the incident angle of a mode-I crack propagating perpendicular to the bedding is likely to lead to a substantial deflection towards bedding-parallel (Short-Transverse) propagation. Further experimental work is currently underway on anisotropic Fracture Toughness measurements at elevated pressures and temperatures, simulating conditions in Shale Gas reservoirs at depths up to around 4km.

Object width modulates object-based attentional selection.

PubMed

Nah, Joseph C; Neppi-Modona, Marco; Strother, Lars; Behrmann, Marlene; Shomstein, Sarah

2018-04-24

Visual input typically includes a myriad of objects, some of which are selected for further processing. While these objects vary in shape and size, most evidence supporting object-based guidance of attention is drawn from paradigms employing two identical objects. Importantly, object size is a readily perceived stimulus dimension, and whether it modulates the distribution of attention remains an open question. Across four experiments, the size of the objects in the display was manipulated in a modified version of the two-rectangle paradigm. In Experiment 1, two identical parallel rectangles of two sizes (thin or thick) were presented. Experiments 2-4 employed identical trapezoids (each having a thin and thick end), inverted in orientation. In the experiments, one end of an object was cued and participants performed either a T/L discrimination or a simple target-detection task. Combined results show that, in addition to the standard object-based attentional advantage, there was a further attentional benefit for processing information contained in the thick versus thin end of objects. Additionally, eye-tracking measures demonstrated increased saccade precision towards thick object ends, suggesting that Fitts's Law may play a role in object-based attentional shifts. Taken together, these results suggest that object-based attentional selection is modulated by object width.

Determining the orientation of depth-rotated familiar objects.

PubMed

Niimi, Ryosuke; Yokosawa, Kazuhiko

2008-02-01

How does the human visual system determine the depth-orientation of familiar objects? We examined reaction times and errors in the detection of 15 degrees differences in the depth orientations of two simultaneously presented familiar objects, which were the same objects (Experiment 1) or different objects (Experiment 2). Detection of orientation differences was best for 0 degrees (front) and 180 degrees (back), while 45 degrees and 135 degrees yielded poorer results, and 90 degrees (side) showed intermediate results, suggesting that the visual system is tuned for front, side and back orientations. We further found that those advantages are due to orientation-specific features such as horizontal linear contours and symmetry, since the 90 degrees advantage was absent for objects with curvilinear contours, and asymmetric object diminished the 0 degrees and 180 degrees advantages. We conclude that the efficiency of visually determining object orientation is highly orientation-dependent, and object orientation may be perceived in favor of front-back axes.

Visual Computing Environment

NASA Technical Reports Server (NTRS)

Lawrence, Charles; Putt, Charles W.

1997-01-01

The Visual Computing Environment (VCE) is a NASA Lewis Research Center project to develop a framework for intercomponent and multidisciplinary computational simulations. Many current engineering analysis codes simulate various aspects of aircraft engine operation. For example, existing computational fluid dynamics (CFD) codes can model the airflow through individual engine components such as the inlet, compressor, combustor, turbine, or nozzle. Currently, these codes are run in isolation, making intercomponent and complete system simulations very difficult to perform. In addition, management and utilization of these engineering codes for coupled component simulations is a complex, laborious task, requiring substantial experience and effort. To facilitate multicomponent aircraft engine analysis, the CFD Research Corporation (CFDRC) is developing the VCE system. This system, which is part of NASA's Numerical Propulsion Simulation System (NPSS) program, can couple various engineering disciplines, such as CFD, structural analysis, and thermal analysis. The objectives of VCE are to (1) develop a visual computing environment for controlling the execution of individual simulation codes that are running in parallel and are distributed on heterogeneous host machines in a networked environment, (2) develop numerical coupling algorithms for interchanging boundary conditions between codes with arbitrary grid matching and different levels of dimensionality, (3) provide a graphical interface for simulation setup and control, and (4) provide tools for online visualization and plotting. VCE was designed to provide a distributed, object-oriented environment. Mechanisms are provided for creating and manipulating objects, such as grids, boundary conditions, and solution data. This environment includes parallel virtual machine (PVM) for distributed processing. Users can interactively select and couple any set of codes that have been modified to run in a parallel distributed fashion on a cluster of heterogeneous workstations. A scripting facility allows users to dictate the sequence of events that make up the particular simulation.

7 CFR 29.3046 - Oriented.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Oriented. A term applied to Type 31 untied tobacco which denotes the arrangement of leaves in a straight and orderly manner. Oriented includes: (a) Any lot of baled tobacco in which the leaves are packed parallel to the length of the bale with the butts to the outside and the tips of the leaves overlapping...

7 CFR 29.3046 - Oriented.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Oriented. A term applied to Type 31 untied tobacco which denotes the arrangement of leaves in a straight and orderly manner. Oriented includes: (a) Any lot of baled tobacco in which the leaves are packed parallel to the length of the bale with the butts to the outside and the tips of the leaves overlapping...

7 CFR 29.3046 - Oriented.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Oriented. A term applied to Type 31 untied tobacco which denotes the arrangement of leaves in a straight and orderly manner. Oriented includes: (a) Any lot of baled tobacco in which the leaves are packed parallel to the length of the bale with the butts to the outside and the tips of the leaves overlapping...

7 CFR 29.3046 - Oriented.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Oriented. A term applied to Type 31 untied tobacco which denotes the arrangement of leaves in a straight and orderly manner. Oriented includes: (a) Any lot of baled tobacco in which the leaves are packed parallel to the length of the bale with the butts to the outside and the tips of the leaves overlapping...

7 CFR 29.3046 - Oriented.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Oriented. A term applied to Type 31 untied tobacco which denotes the arrangement of leaves in a straight and orderly manner. Oriented includes: (a) Any lot of baled tobacco in which the leaves are packed parallel to the length of the bale with the butts to the outside and the tips of the leaves overlapping...

New Trends in E-Science: Machine Learning and Knowledge Discovery in Databases

NASA Astrophysics Data System (ADS)

Brescia, Massimo

2012-11-01

Data mining, or Knowledge Discovery in Databases (KDD), while being the main methodology to extract the scientific information contained in Massive Data Sets (MDS), needs to tackle crucial problems since it has to orchestrate complex challenges posed by transparent access to different computing environments, scalability of algorithms, reusability of resources. To achieve a leap forward for the progress of e-science in the data avalanche era, the community needs to implement an infrastructure capable of performing data access, processing and mining in a distributed but integrated context. The increasing complexity of modern technologies carried out a huge production of data, whose related warehouse management and the need to optimize analysis and mining procedures lead to a change in concept on modern science. Classical data exploration, based on local user own data storage and limited computing infrastructures, is no more efficient in the case of MDS, worldwide spread over inhomogeneous data centres and requiring teraflop processing power. In this context modern experimental and observational science requires a good understanding of computer science, network infrastructures, Data Mining, etc. i.e. of all those techniques which fall into the domain of the so called e-science (recently assessed also by the Fourth Paradigm of Science). Such understanding is almost completely absent in the older generations of scientists and this reflects in the inadequacy of most academic and research programs. A paradigm shift is needed: statistical pattern recognition, object oriented programming, distributed computing, parallel programming need to become an essential part of scientific background. A possible practical solution is to provide the research community with easy-to understand, easy-to-use tools, based on the Web 2.0 technologies and Machine Learning methodology. Tools where almost all the complexity is hidden to the final user, but which are still flexible and able to produce efficient and reliable scientific results. All these considerations will be described in the detail in the chapter. Moreover, examples of modern applications offering to a wide variety of e-science communities a large spectrum of computational facilities to exploit the wealth of available massive data sets and powerful machine learning and statistical algorithms will be also introduced.

Massive ordering and alignment of cylindrical micro-objects by photovoltaic optoelectronic tweezers.

PubMed

Elvira, Iris; Muñoz-Martínez, Juan F; Barroso, Álvaro; Denz, Cornelia; Ramiro, José B; García-Cabañes, Angel; Agulló-López, Fernando; Carrascosa, Mercedes

2018-01-01

Optical tools for manipulation and trapping of micro- and nano-objects are a fundamental issue for many applications in nano- and biotechnology. This work reports on the use of one such method, known as photovoltaic optoelectronics tweezers, to orientate and organize cylindrical microcrystals, specifically elongated zeolite L, on the surface of Fe-doped LiNbO 3 crystal plates. Patterns of aligned zeolites have been achieved through the forces and torques generated by the bulk photovoltaic effect. The alignment patterns with zeolites parallel or perpendicular to the substrate surface are highly dependent on the features of light distribution and crystal configuration. Moreover, dielectrophoretic chains of zeolites with lengths up to 100 μm have often been observed. The experimental results of zeolite trapping and alignment have been discussed and compared together with theoretical simulations of the evanescent photovoltaic electric field and the dielectrophoretic potential. They demonstrate the remarkable capabilities of the optoelectronic photovoltaic method to orientate and pattern anisotropic microcrystals. The combined action of patterning and alignment offers a unique tool to prepare functional nanostructures with potential applications in a variety of fields such as nonlinear optics or plasmonics.

Texture inheritance from austenite to 7 M martensite in Ni-Mn-Ga melt-spun ribbons

NASA Astrophysics Data System (ADS)

Li, Zongbin; Jiang, Yiwen; Li, Zhenzhuang; Yang, Yiqiao; Yang, Bo; Zhang, Yudong; Esling, Claude; Zhao, Xiang; Zuo, Liang

In this work, Ni53Mn22Ga25 and Ni51Mn27Ga22 ribbons with austenite and 7 M martensite at room temperature respectively, were prepared by melt-spinning. Through the detailed crystallographic analyses, the preferred orientation in ribbons was confirmed. It is shown that the austenite in Ni53Mn22Ga25 ribbons forms a preferred orientation with {4 0 0}A in parallel to ribbon plane, whereas the 7 M martensite in Ni51Mn27Ga22 ribbons develops the preferred orientation with {2 0 -20}7M, {2 0 20}7M, and {0 4 0}7M crystallographic planes parallel to the ribbon plane. Since {2 0 -20}7M, {2 0 20}7M, and {0 4 0}7M are originated from {4 0 0}A, the preferred orientation in ribbons thus can be inherited after the martensitic transformation. Such texture inheritance is attributed to the intrinsic orientation relationship between austenite and 7 M martensite.

Narrow bandgap semiconducting silicides: Intrinsic infrared detectors on a silicon chip

NASA Technical Reports Server (NTRS)

Mahan, John E.

1990-01-01

Work done during the final report period is presented. The main technical objective was to achieve epitaxial growth on silicon of two semiconducting silicides, ReSi2 and CrSi2. ReSi2 thin films were grown on (001) silicon wafers by vacuum evaporation of rhenium onto hot substrates in ultrahigh vacuum. The preferred epitaxial relationship was found to be ReSi2(100)/Si(001) with ReSi2(010) parallel to Si(110). The lattice matching consists of a common unit mesh of 120 A(sup 2) area, and a mismatch of 1.8 percent. Transmission electron microscopy revealed the existence of rotation twins corresponding to two distinct but equivalent azimuthal orientations of the common unit mesh. MeV He(+) backscattering spectrometry revealed a minimum channeling yield of 2 percent for an approximately 1,500 A thick film grown at 650 C. Although the lateral dimension of the twins is on the order of 100 A, there is a very high degree of alignment between the ReSi2(100) and the Si(001) planes. Highly oriented films of CrSi2 were grown on (111) silicon substrates, with the matching crystallographic faces being CrSi2(001)/Si(111). The reflection high-energy electron diffraction (RHEED) patterns of the films consist of sharp streaks, symmetrically arranged. The predominant azimuthal orientation of the films was determined to be CrSi2(210) parallel to Si(110). This highly desirable heteroepitaxial relationship has been obtained previously by others; it may be described with a common unit mesh of 51 A(sup 2) and mismatch of 0.3 percent. RHEED also revealed the presence of limited film regions of a competing azimuthal orientation, CrSi2(110) parallel to Si(110). A channeling effect for MeV He(+) ions was not found for this material. Potential commercial applications of this research may be found in silicon-integrated infrared detector arrays. Optical characterizations showed that semiconducting ReSi2 is a strong absorber of infrared radiation, with the adsorption constant increasing above 2 x 10(exp 4) cm(sup -1) for photon energies above 0.2 eV. CrSi2 is of potential utility for detection at photon energies above approximately 0.3 eV.

3-D Hybrid Kinetic Modeling of the Interaction Between the Solar Wind and Lunar-like Exospheric Pickup Ions in Case of Oblique/ Quasi-Parallel/Parallel Upstream Magnetic Field

NASA Technical Reports Server (NTRS)

Lipatov, A. S.; Farrell, W. M.; Cooper, J. F.; Sittler, E. C., Jr.; Hartle, R. E.

2015-01-01

The interactions between the solar wind and Moon-sized objects are determined by a set of the solar wind parameters and plasma environment of the space objects. The orientation of upstream magnetic field is one of the key factors which determines the formation and structure of bow shock wave/Mach cone or Alfven wing near the obstacle. The study of effects of the direction of the upstream magnetic field on lunar-like plasma environment is the main subject of our investigation in this paper. Photoionization, electron-impact ionization and charge exchange are included in our hybrid model. The computational model includes the self-consistent dynamics of the light (hydrogen (+), helium (+)) and heavy (sodium (+)) pickup ions. The lunar interior is considered as a weakly conducting body. Our previous 2013 lunar work, as reported in this journal, found formation of a triple structure of the Mach cone near the Moon in the case of perpendicular upstream magnetic field. Further advances in modeling now reveal the presence of strong wave activity in the upstream solar wind and plasma wake in the cases of quasiparallel and parallel upstream magnetic fields. However, little wave activity is found for the opposite case with a perpendicular upstream magnetic field. The modeling does not show a formation of the Mach cone in the case of theta(Sub B,U) approximately equal to 0 degrees.

Xyce parallel electronic simulator : users' guide.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mei, Ting; Rankin, Eric Lamont; Thornquist, Heidi K.

2011-05-01

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: (1) Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). Note that this includes support for most popular parallel and serial computers; (2) Improved performance for all numerical kernels (e.g., time integrator, nonlinear and linear solvers) through state-of-the-artmore » algorithms and novel techniques. (3) Device models which are specifically tailored to meet Sandia's needs, including some radiation-aware devices (for Sandia users only); and (4) Object-oriented code design and implementation using modern coding practices that ensure that the Xyce Parallel Electronic Simulator will be maintainable and extensible far into the future. Xyce is a parallel code in the most general sense of the phrase - a message passing parallel implementation - which allows it to run efficiently on the widest possible number of computing platforms. These include serial, shared-memory and distributed-memory parallel as well as heterogeneous platforms. Careful attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows. The development of Xyce provides a platform for computational research and development aimed specifically at the needs of the Laboratory. With Xyce, Sandia has an 'in-house' capability with which both new electrical (e.g., device model development) and algorithmic (e.g., faster time-integration methods, parallel solver algorithms) research and development can be performed. As a result, Xyce is a unique electrical simulation capability, designed to meet the unique needs of the laboratory.« less

Parallel-hierarchical processing and classification of laser beam profile images based on the GPU-oriented architecture

NASA Astrophysics Data System (ADS)

Yarovyi, Andrii A.; Timchenko, Leonid I.; Kozhemiako, Volodymyr P.; Kokriatskaia, Nataliya I.; Hamdi, Rami R.; Savchuk, Tamara O.; Kulyk, Oleksandr O.; Surtel, Wojciech; Amirgaliyev, Yedilkhan; Kashaganova, Gulzhan

2017-08-01

The paper deals with a problem of insufficient productivity of existing computer means for large image processing, which do not meet modern requirements posed by resource-intensive computing tasks of laser beam profiling. The research concentrated on one of the profiling problems, namely, real-time processing of spot images of the laser beam profile. Development of a theory of parallel-hierarchic transformation allowed to produce models for high-performance parallel-hierarchical processes, as well as algorithms and software for their implementation based on the GPU-oriented architecture using GPGPU technologies. The analyzed performance of suggested computerized tools for processing and classification of laser beam profile images allows to perform real-time processing of dynamic images of various sizes.

Towards the Compatibility of Professional and Scientific Learning Outcomes: Insights and Options in the Context of Competence Orientation

ERIC Educational Resources Information Center

Rein, Volker

2017-01-01

The steady increase in science-related requirements in operational areas of skilled and managing workforce is influencing worldwide the discourse on shaping professionalization. This article focuses on the compatibility of professional and scientific competence-oriented learning outcomes of qualification programmes within and across the education…

Method for adhering a coating to a substrate structure

DOEpatents

Taxacher, Glenn Curtis; Crespo, Andres Garcia; Roberts, III, Herbert Chidsey

2015-02-17

A method for adhering a coating to a substrate structure comprises selecting a substrate structure having an outer surface oriented substantially parallel to a direction of radial stress, modifying the outer surface to provide a textured region having steps to adhere a coating thereto, and applying a coating to extend over at least a portion of the textured region, wherein the steps are oriented substantially perpendicular to the direction of radial stress to resist deformation of the coating relative to the substrate structure. A rotating component comprises a substrate structure having an outer surface oriented substantially parallel to a direction of radial stress. The outer surface defines a textured region having steps to adhere a coating thereto, and a coating extends over at least a portion of the textured region. The steps are oriented substantially perpendicular to the direction of radial stress to resist creep.

ROSE Version 1.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quinlan, D.; Yi, Q.; Buduc, R.

2005-02-17

ROSE is an object-oriented software infrastructure for source-to-source translation that provides an interface for programmers to write their own specialized translators for optimizing scientific applications. ROSE is a part of current research on telescoping languages, which provides optimizations of the use of libraries in scientific applications. ROSE defines approaches to extend the optimization techniques, common in well defined languages, to the optimization of scientific applications using well defined libraries. ROSE includes a rich set of tools for generating customized transformations to support optimization of applications codes. We currently support full C and C++ (including template instantiation etc.), with Fortran 90more » support under development as part of a collaboration and contract with Rice to use their version of the open source Open64 F90 front-end. ROSE represents an attempt to define an open compiler infrastructure to handle the full complexity of full scale DOE applications codes using the languages common to scientific computing within DOE. We expect that such an infrastructure will also be useful for the development of numerous tools that may then realistically expect to work on DOE full scale applications.« less

General object-oriented software development

NASA Technical Reports Server (NTRS)

Seidewitz, Edwin V.; Stark, Mike

1986-01-01

Object-oriented design techniques are gaining increasing popularity for use with the Ada programming language. A general approach to object-oriented design which synthesizes the principles of previous object-oriented methods into the overall software life-cycle, providing transitions from specification to design and from design to code. It therefore provides the basis for a general object-oriented development methodology.

High magnetic field processing of liquid crystalline polymers

DOEpatents

Smith, M.E.; Benicewicz, B.C.; Douglas, E.P.

1998-11-24

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

High magnetic field processing of liquid crystalline polymers

DOEpatents

Smith, Mark E.; Benicewicz, Brian C.; Douglas, Elliot P.

1998-01-01

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

[An object-oriented remote sensing image segmentation approach based on edge detection].

PubMed

Tan, Yu-Min; Huai, Jian-Zhu; Tang, Zhong-Shi

2010-06-01

Satellite sensor technology endorsed better discrimination of various landscape objects. Image segmentation approaches to extracting conceptual objects and patterns hence have been explored and a wide variety of such algorithms abound. To this end, in order to effectively utilize edge and topological information in high resolution remote sensing imagery, an object-oriented algorithm combining edge detection and region merging is proposed. Susan edge filter is firstly applied to the panchromatic band of Quickbird imagery with spatial resolution of 0.61 m to obtain the edge map. Thanks to the resulting edge map, a two-phrase region-based segmentation method operates on the fusion image from panchromatic and multispectral Quickbird images to get the final partition result. In the first phase, a quad tree grid consisting of squares with sides parallel to the image left and top borders agglomerates the square subsets recursively where the uniform measure is satisfied to derive image object primitives. Before the merger of the second phrase, the contextual and spatial information, (e. g., neighbor relationship, boundary coding) of the resulting squares are retrieved efficiently by means of the quad tree structure. Then a region merging operation is performed with those primitives, during which the criterion for region merging integrates edge map and region-based features. This approach has been tested on the QuickBird images of some site in Sanxia area and the result is compared with those of ENVI Zoom Definiens. In addition, quantitative evaluation of the quality of segmentation results is also presented. Experiment results demonstrate stable convergence and efficiency.

Controlled Growth of Parallel Oriented ZnO Nanostructural Arrays on Ga2O3 Nanowires

DTIC Science & Technology

2008-11-01

Controlled Growth of Parallel Oriented ZnO Nanostructural Arrays on Ga2O3 Nanowires Lena Mazeina,* Yoosuf N. Picard, and Sharka M. Prokes Electronics...Manuscript ReceiVed NoVember 6, 2008 ABSTRACT: Novel hierarchical ZnO- Ga2O3 nanostructures were fabricated via a two stage growth process. Nanowires of Ga2O3 ...nanobrushes (NBs) with Ga2O3 as the core and ZnO as the branches self-assembling symmetrically in six equiangular directions around the core

Current distribution on a cylindrical antenna with parallel orientation in a lossy magnetoplasma

NASA Technical Reports Server (NTRS)

Klein, C. A.; Klock, P. W.; Deschamps, G. A.

1972-01-01

The current distribution and impedance of a thin cylindrical antenna with parallel orientation to the static magnetic field of a lossy magnetoplasma is calculated with the method of moments. The electric field produced by an infinitesimal current source is first derived. Results are presented for a wide range of plasma parameters. Reasonable answers are obtained for all cases except for the overdense hyperbolic case. A discussion of the numerical stability is included which not only applies to this problem but other applications of the method of moments.

Performance and Scalability of the NAS Parallel Benchmarks in Java

NASA Technical Reports Server (NTRS)

Frumkin, Michael A.; Schultz, Matthew; Jin, Haoqiang; Yan, Jerry; Biegel, Bryan A. (Technical Monitor)

2002-01-01

Several features make Java an attractive choice for scientific applications. In order to gauge the applicability of Java to Computational Fluid Dynamics (CFD), we have implemented the NAS (NASA Advanced Supercomputing) Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would position Java closer to Fortran in the competition for scientific applications.

Enceladus Jet Orientations: Effects of Surface Structure

NASA Astrophysics Data System (ADS)

Helfenstein, P.; Porco, C.; DiNino, D.

2013-12-01

Jetting activity across the South Polar Terrain (SPT) of Enceladus is now known to erupt directly from tiger-stripe rifts and associated fracture systems. However, details of the vent conduit geometry are hidden below the icy surface. The three-dimensional orientations of the erupting jets may provide important clues. Porco et al. (2013, Lunar Planet. Sci. Conf. 44th, p.1775) surveyed jet locations and orientations as imaged at high resolution (< 1.3 km/pixel) by Cassini ISS from 2005 through May 2012. Ninety-eight (98) jets were identified either on the main trunks or branches of the 4 tiger-stripes. The azimuth angles of the jets are seen to vary across the SPT. Here, we use histogram analysis of the survey data to test if the jet azimuths are influenced by their placement relative to surface morphology and tectonic structures. Azimuths are measured positive counterclockwise with zero pointing along the fracture in the direction of the sub-Saturn hemisphere, and rosette histograms were binned in 30° increments. Overall, the jet azimuths are not random and only about 11% of them are co-aligned with the tiger stripe valley. There are preferred diagonal orientations between 105°-165° and again between 255°-345°. These trends are dominant along the Damascus and Baghdad tiger-stripes where more than half of the jets are found. Histograms for Cairo and Alexandria show less-distinct trends, fewer jets being measured there, but combining data from both suggests a different pattern of preferred orientations; from 45°-75° and 265°-280°. Many possible factors could affect the orientations of jets, for example, the conduit shape, the presence of obstacles like narrow medial ridges called 'shark-fins' along tiger-stripe valleys, the possibility that jets may breach the surface at some point other than the center of a tiger-stripe, and the presence of structural fabrics or mechanical weaknesses, such as patterns of cross-cutting fractures. The dominance of diagonally crossing azimuths for Damascus and Baghdad suggest that cross-cutting fractures may significantly control jet orientations. At the 100 m/pixel scale of our Enceladus basemap at least 24% of the jets have azimuth orientations that point along or parallel to nearby fractures or fabrics of parallel fractures that approach or intersect the tiger stripe. Structural control of jet orientations by local tectonism is especially suggested by a systematic pattern of jet orientations at the distal end of Damascus Sulcus where it bifurcates into a northern and a southern branch, respectively. The five most distal jets along the northern branch are nearly parallel and point northward while the three most distal jets along the southern branch are also nearly parallel, but they point in the opposite direction. Additional work is needed to show the extent to which jet orientations may be affected at smaller scales by quasi-parallel systems of cross-cutting gossamer fractures or by curving axial discontinuities along the tiger stripes (cf. Helfenstein et al. 2011, http://encfg.ciclops.org/reg/uploads/20110425220109_helfenstein_enceladus_workshop_2011.pdf).

On the measurement of fiber orientation in fiberboard

Treesearch

Otto Suchsland; Charles W. McMillin

1983-01-01

An attempt to measure the vertical component of fiber orientation in fiberboard is described. The experiment is based on the obvious reduction of the furnish fiber length which occurs by cutting thin microtome sections of the board parallel to the board plane. Only when no vertical fiber orientation component is present will the fibers contained in these sections have...

Shape detection of Gaborized outline versions of everyday objects

PubMed Central

Sassi, Michaël; Machilsen, Bart; Wagemans, Johan

2012-01-01

We previously tested the identifiability of six versions of Gaborized outlines of everyday objects, differing in the orientations assigned to elements inside and outside the outline. We found significant differences in identifiability between the versions, and related a number of stimulus metrics to identifiability [Sassi, M., Vancleef, K., Machilsen, B., Panis, S., & Wagemans, J. (2010). Identification of everyday objects on the basis of Gaborized outline versions. i-Perception, 1(3), 121–142]. In this study, after retesting the identifiability of new variants of three of the stimulus versions, we tested their robustness to local orientation jitter in a detection experiment. In general, our results replicated the key findings from the previous study, and allowed us to substantiate our earlier interpretations of the effects of our stimulus metrics and of the performance differences between the different stimulus versions. The results of the detection task revealed a different ranking order of stimulus versions than the identification task. By examining the parallels and differences between the effects of our stimulus metrics in the two tasks, we found evidence for a trade-off between shape detectability and identifiability. The generally simple and smooth shapes that yield the strongest contour integration and most robust detectability tend to lack the distinguishing features necessary for clear-cut identification. Conversely, contours that do contain such identifying features tend to be inherently more complex and, therefore, yield weaker integration and less robust detectability. PMID:23483752

Object-oriented numerics with FOSS: comparing PyPy &amp; NumPy, GCC/Clang &amp; Bitz++ and Gfortran

NASA Astrophysics Data System (ADS)

Jarecka, Dorota; Arabas, Sylwester; Fijalkowski, Maciej; Jaruga, Anna; Del Vento, Davide

2013-04-01

Employment of object-oriented programming (OOP) techniques may help to improve code readability, and hence its auditability and maintainability - both being arguably crucial for scientific software. OOP offers, in particular, the possibility to reproduce in the program code the mathematical "blackboard abstractions" used in the literature. There exist a number of free and open-source tools allowing to obtain this goal without sacrificing performance. An OOP implementation of the MPDATA advection algorithm used as a core of weather, ocean and climate modelling systems will serve as an example for briefly highlighting some relevant recent FOSS developments including: - NumPy support in the PyPy just-in-time compiler of Python. - the Blitz++ library coupled with the C++11 support in GCC and Clang; - support for OOP constructs from Fortran 2003/2008 in GFortran; A brief overview of other performance-related packages for Python like Numba and Cython will be also given. This poster will describe and extends key findings presented in http://arxiv.org/abs/1301.1334

Multiphysics Object Oriented Simulation Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

The Multiphysics Object Oriented Simulation Environment (MOOSE) software library developed at Idaho National Laboratory is a tool. MOOSE, like other tools, doesn't actually complete a task. Instead, MOOSE seeks to reduce the effort required to create engineering simulation applications. MOOSE itself is a software library: a blank canvas upon which you write equations and then MOOSE can help you solve them. MOOSE is comparable to a spreadsheet application. A spreadsheet, by itself, doesn't do anything. Only once equations are entered into it will a spreadsheet application compute anything. Such is the same for MOOSE. An engineer or scientist can utilizemore » the equation solvers within MOOSE to solve equations related to their area of study. For instance, a geomechanical scientist can input equations related to water flow in underground reservoirs and MOOSE can solve those equations to give the scientist an idea of how water could move over time. An engineer might input equations related to the forces in steel beams in order to understand the load bearing capacity of a bridge. Because MOOSE is a blank canvas it can be useful in many scientific and engineering pursuits.« less

Present-day stress state analysis on the Big Island of Hawaíi, USA

NASA Astrophysics Data System (ADS)

Pierdominici, Simona; Kueck, Jochem; Millett, John; Planke, Sverre; Jerram, Dougal A.; Haskins, Eric; Thomas, Donald

2017-04-01

We analyze and interpret the stress features from a c. 1.5 km deep fully cored borehole (PTA2) on the Big Island of Hawaíi within the Humúula saddle region, between the Mauna Kea and Mauna Loa volcanoes. The Big Island of Hawaii comprises the largest and youngest island of the Hawaiian-Emperor seamount chain and is volumetrically dominated by shield stage tholeiitic volcanic rocks. Mauna Kea is dormant whereas Mauna Loa is still active. There are also a series of normal faults on Mauna Loa's northern and western slopes, between its two major rift zones, that are believed to be the result of combined circumferential tension from the two rift zones and from added pressure due to the westward growth of the neighboring Kīlauea volcano. The PTA2 borehole was drilled in 2013 into lava dominated formation (Pahoehoe and Aā) as part of the Humúula Groundwater Research Project (HGPR) with the purpose of characterizing the groundwater resource potential in this area. In 2016 two downhole logging campaigns were performed by the Operational Support Group of the International Continental Scientific Drilling Program (ICDP) to acquire a set of geophysical data as part of the Volcanic Margin Petroleum Prospectivity (VMAPP) project. The main objective of the logging campaign was to obtain high quality wireline log data to enable a detailed core-log integration of the volcanic sequence and to improve understanding of the subsurface expression of volcanic rocks. We identify stress features (e.g. borehole breakouts) and volcanic structures (e.g. flow boundaries, vesicles and jointing) at depth using borehole images acquired with an ABI43 acoustic borehole televiewer. We analyzed and interpreted the stress indicators and compared their orientation with the regional stress pattern. We identified a set of stress indicators along the hole dominantly concentrated within the lower logged interval of the PTA2 borehole. Two primary horizontal stress indicators have been taken into account: borehole breakouts (bidirectional enlargements) (BB) and drilling induced tensile fractures (DIF). BB and DIF occur when the stresses around the borehole exceed the compressive and tensile yield stress of the borehole wall rock respectively causing failure. A breakout is caused by the development of intersecting conjugate shear planes that cause pieces of the borehole wall to spall off. For a breakout to develop, the stress concentration around a vertical borehole is largest in the direction of the minimum horizontal stress. Hence, BB develops approximately parallel to the orientation of the minimum horizontal stress. For the DIF, the stress concentration around a vertical borehole is at a minimum in the maximum horizontal stress direction. Hence, DIF develop approximately parallel to the orientation of the maximum horizontal stress. Based on the World Stress Map, the present-day stress in this area is defined only by focal mechanism solutions. These data give a unique opportunity to characterize the orientation of the present-day stress field between two large volume shield volcanoes on an active volcanic island using a different approach and stress indicators.

Real-Time Examination of Atomistic Mechanisms during Shock-Induced Structural Transformation in Silicon

DOE PAGES

Turneaure, Stefan J.; Sinclair, N.; Gupta, Y. M.

2016-07-20

Experimental determination of atomistic mechanisms linking crystal structures during a compression driven solid-solid phase transformation is a long standing and challenging scientific objective. Also, when using new capabilities at the Dynamic Compression Sector at the Advanced Photon Source, the structure of shocked Si at 19 GPa was identified as simple hexagonal and the lattice orientations between ambient cubic diamond and simple hexagonal structures were related. Furthermore, this approach is general and provides a powerful new method for examining atomistic mechanisms during stress-induced structural changes.

Shwirl: Meaningful coloring of spectral cube data with volume rendering

NASA Astrophysics Data System (ADS)

Vohl, Dany

2017-04-01

Shwirl visualizes spectral data cubes with meaningful coloring methods. The program has been developed to investigate transfer functions, which combines volumetric elements (or voxels) to set the color, and graphics shaders, functions used to compute several properties of the final image such as color, depth, and/or transparency, as enablers for scientific visualization of astronomical data. The program uses Astropy (ascl:1304.002) to handle FITS files and World Coordinate System, Qt (and PyQt) for the user interface, and VisPy, an object-oriented Python visualization library binding onto OpenGL.

Visual Search for Object Orientation Can Be Modulated by Canonical Orientation

ERIC Educational Resources Information Center

Ballaz, Cecile; Boutsen, Luc; Peyrin, Carole; Humphreys, Glyn W.; Marendaz, Christian

2005-01-01

The authors studied the influence of canonical orientation on visual search for object orientation. Displays consisted of pictures of animals whose axis of elongation was either vertical or tilted in their canonical orientation. Target orientation could be either congruent or incongruent with the object's canonical orientation. In Experiment 1,…

Effect of alignment of easy axes on dynamic magnetization of immobilized magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Yoshida, Takashi; Matsugi, Yuki; Tsujimura, Naotaka; Sasayama, Teruyoshi; Enpuku, Keiji; Viereck, Thilo; Schilling, Meinhard; Ludwig, Frank

2017-04-01

In some biomedical applications of magnetic nanoparticles (MNPs), the particles are physically immobilized. In this study, we explore the effect of the alignment of the magnetic easy axes on the dynamic magnetization of immobilized MNPs under an AC excitation field. We prepared three immobilized MNP samples: (1) a sample in which easy axes are randomly oriented, (2) a parallel-aligned sample in which easy axes are parallel to the AC field, and (3) an orthogonally aligned sample in which easy axes are perpendicular to the AC field. First, we show that the parallel-aligned sample has the largest hysteresis in the magnetization curve and the largest harmonic magnetization spectra, followed by the randomly oriented and orthogonally aligned samples. For example, 1.6-fold increase was observed in the area of the hysteresis loop of the parallel-aligned sample compared to that of the randomly oriented sample. To quantitatively discuss the experimental results, we perform a numerical simulation based on a Fokker-Planck equation, in which probability distributions for the directions of the easy axes are taken into account in simulating the prepared MNP samples. We obtained quantitative agreement between experiment and simulation. These results indicate that the dynamic magnetization of immobilized MNPs is significantly affected by the alignment of the easy axes.

The Development of a Model to Determine Perceptions of Scientific Literacy.

ERIC Educational Resources Information Center

Gabel, Lawrence Lee

Dimensions of scientific literacy with regard to a theoretical definition were inferred for a group of science oriented persons, a group of nonscience oriented persons, and the two groups combined. Comparisons of the strength of agreement of the two groups, and of subgroups of the two groups, with the inferred dimensions were made. The sample…

Secondary school physics teachers' conceptions of scientific evidence: A collective case study

NASA Astrophysics Data System (ADS)

Taylor, Joseph A.

Engaging secondary school students in inquiry-oriented tasks that more closely simulate the scholarly activities of scientists has been recommended as a way to improve scientific literacy. Two tasks that are frequently recommended include students' design of original experiments, and students' evaluation of scientific evidence and conclusions. Yet, little is known about teachers' conceptions of experimentation. The principal aim of this study, therefore, was to describe the nature of prospective and practicing physics teachers' conceptions of scientific evidence. More specifically, the following research questions guided this study: (1) What types of issues related to the measurement reliability and experimental validity of scientific evidence do practicing and prospective physics teachers think about when designing experiments? (2) When presented with hypothetical scenarios that describe unsound experimental procedures or poorly supported conclusions (or both), what concerns will prospective and practicing physics teachers raise? And (3) When the participants' responses to parallel research prompts are compared across protocols, what similarities and differences exist? The nature of the teacher-participants' conceptions was described from an analysis of data collected from research prompts such as interviews and hand written artifacts. In these research prompts, the teachers "thought aloud" while designing experiments and critically evaluated student-collected evidence presented in hypothetical classroom scenarios. The data from this study suggested that the three teachers, while contemplating the reliability and validity of scientific evidence, frequently used their conceptions of evidence in conjunction with specific subject matter conceptions. The data also indicated that the relationship between subject matter knowledge and conceptions of evidence was more pronounced for some conceptions of evidence than for others. Suggestions for future research included conducting similar studies in other physics content areas as well as other scientific disciplines. Implications for science teacher education suggested that science and science methods courses encourage the construction of evidence-based arguments, as well as engagement in peer review and critique.

Fast I/O for Massively Parallel Applications

NASA Technical Reports Server (NTRS)

OKeefe, Matthew T.

1996-01-01

The two primary goals for this report were the design, contruction and modeling of parallel disk arrays for scientific visualization and animation, and a study of the IO requirements of highly parallel applications. In addition, further work in parallel display systems required to project and animate the very high-resolution frames resulting from our supercomputing simulations in ocean circulation and compressible gas dynamics.

The IUR Forum: Worldwide Harmonisation of Networks to Support Integration of Scientific Knowledge and Consensus Development in Radioecology.

PubMed

Bréchignac, F; Alexakhin, R; Bollhöfer, A; Frogg, K E; Hardeman, F; Higley, K; Hinton, T G; Kapustka, L A; Kuhne, W; Leonard, K; Masson, O; Nanba, K; Smith, G; Smith, K; Strand, P; Vandenhove, H; Yankovich, T; Yoshida, S

2017-04-01

During the past decades, many specialised networks have formed to meet specific radioecological objectives, whether regional or sectorial (purpose-oriented). Regional networks deal with an array of radioecological issues related to their territories. Examples include the South Pacific network of radioecologists, and the European network of excellence in radioecology. The latter is now part of the European platform for radiation protection. Sectorial networks are more problem-oriented, often with wider international representativeness, but restricted to one specific issue, (e.g. radioactive waste, low-level atmospheric contamination, modelling). All such networks, while often working in relative isolation, contribute to a flow of scientific information which, through United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR's) efforts of synthesis, feeds into the radiation protection frameworks of protecting humans and the environment. The IUR has therefore prompted a co-construction process aimed at improving worldwide harmonisation of radioecology networks. An initiative based on an initial set of 15 networks, now called the IUR FORUM, was launched in June 2014. The IUR Forum agreed to build a framework for improved coordination of scientific knowledge, integration and consensus development relative to environmental radioactivity. Three objectives have been collectively assigned to the IUR FORUM: (1) coordination, (2) global integration and construction of consensus and (3) maintenance of expertise. One particular achievement of the FORUM was an improved description and common understanding of the respective roles and functions of the various networks within the overall scene of radioecology R&D. It clarifies how the various networks assembled within the IUR FORUM interface with UNSCEAR and other international regulatory bodies (IAEA, ICRP), and how consensus on the assessment of risk is constructed. All these agencies interact with regional networks covering different geographical areas, and with other networks which address specific topics within radiation protection. After holding its first Consensus Symposium in 2015, examining the possible ecological impact of radiation from environmental contamination, the IUR FORUM continues its work towards improved radiation protection of humans and the environment. We welcome new members. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Psychophysical parallelism. On a discursive figure in the field of scientific changes in the late 19th century].

PubMed

Wegener, Mai

2009-01-01

The article traces the rise and fall of "psychophysical parallelism" - which was the most advanced scientific formulation of the mind / body relationship in the second half of the 19th century - through an interdisciplinary and broad geographical spectrum. It sheds light on the extremely different positions that rallied round this discursive figure, ranging from Fechner, Hering, Mach, Wundt, Bain, Hughlings Jackson, and Taine to Freud and Saussure. The article develops the thesis that the psychophysical parallelism functioned as a 'hot zone' within and a symptom of the changes in the order of sciences at that time. Against that background, the criticism of the psychophysical parallelism which became prominent around 1900 (Stumpf, Busse, Bergson, Mauthner et. al.) indicates the cooling of this 'hot zone' and the establishment of a new order within the scientific disciplines. The article pays particular attention to the position of this figure in contemporaneous language theories. Its basic assumption is that the relationship between the body and the psyche is itself constituted by language.

Profiling and Improving I/O Performance of a Large-Scale Climate Scientific Application

NASA Technical Reports Server (NTRS)

Liu, Zhuo; Wang, Bin; Wang, Teng; Tian, Yuan; Xu, Cong; Wang, Yandong; Yu, Weikuan; Cruz, Carlos A.; Zhou, Shujia; Clune, Tom;

The influence of glass fibers on elongational viscosity studied by means of optical coherence tomography and X-ray computed tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aigner, M., E-mail: michael.aigner@jku.at; Köpplmayr, T., E-mail: thomas.koepplmayr@jku.at, E-mail: Christian.lang@jku.at; Lang, C., E-mail: thomas.koepplmayr@jku.at, E-mail: Christian.lang@jku.at

2014-05-15

We report on the flow characteristics of glass-fiber-reinforced polymers in elongational rheometry. Unlike polymers with geometrically isotropic fillers, glass-fiber-reinforced polymers exhibit flow behavior and rheology that depend heavily on the orientation, the length distribution and the content of the fibers. One of the primary objectives of this study was to determine the effect of fiber orientation, concentration and distribution on the entrance pressure drop by means of optical coherence tomography (OCT), full-field optical coherence microscopy (FF-OCM), and X-ray computed tomography (X-CT). Both pressure drop and melt flow were analyzed using a special elongation die (Thermo Scientific X-Die [3]) for inlinemore » measurements. Samples with a variety of fiber volume fractions, fiber lengths and processing temperatures were measured.« less

The LSST Data Mining Research Agenda

NASA Astrophysics Data System (ADS)

Borne, K.; Becla, J.; Davidson, I.; Szalay, A.; Tyson, J. A.

2008-12-01

We describe features of the LSST science database that are amenable to scientific data mining, object classification, outlier identification, anomaly detection, image quality assurance, and survey science validation. The data mining research agenda includes: scalability (at petabytes scales) of existing machine learning and data mining algorithms; development of grid-enabled parallel data mining algorithms; designing a robust system for brokering classifications from the LSST event pipeline (which may produce 10,000 or more event alerts per night) multi-resolution methods for exploration of petascale databases; indexing of multi-attribute multi-dimensional astronomical databases (beyond spatial indexing) for rapid querying of petabyte databases; and more.

The direction of stretch-induced cell and stress fiber orientation depends on collagen matrix stress.

PubMed

Tondon, Abhishek; Kaunas, Roland

2014-01-01

Cell structure depends on both matrix strain and stiffness, but their interactive effects are poorly understood. We investigated the interactive roles of matrix properties and stretching patterns on cell structure by uniaxially stretching U2OS cells expressing GFP-actin on silicone rubber sheets supporting either a surface-adsorbed coating or thick hydrogel of type-I collagen. Cells and their actin stress fibers oriented perpendicular to the direction of cyclic stretch on collagen-coated sheets, but oriented parallel to the stretch direction on collagen gels. There was significant alignment parallel to the direction of a steady increase in stretch for cells on collagen gels, while cells on collagen-coated sheets did not align in any direction. The extent of alignment was dependent on both strain rate and duration. Stretch-induced alignment on collagen gels was blocked by the myosin light-chain kinase inhibitor ML7, but not by the Rho-kinase inhibitor Y27632. We propose that active orientation of the actin cytoskeleton perpendicular and parallel to direction of stretch on stiff and soft substrates, respectively, are responses that tend to maintain intracellular tension at an optimal level. Further, our results indicate that cells can align along directions of matrix stress without collagen fibril alignment, indicating that matrix stress can directly regulate cell morphology.

Physical modeling and high-performance GPU computing for characterization, interception, and disruption of hazardous near-Earth objects

NASA Astrophysics Data System (ADS)

Kaplinger, Brian Douglas

For the past few decades, both the scientific community and the general public have been becoming more aware that the Earth lives in a shooting gallery of small objects. We classify all of these asteroids and comets, known or unknown, that cross Earth's orbit as near-Earth objects (NEOs). A look at our geologic history tells us that NEOs have collided with Earth in the past, and we expect that they will continue to do so. With thousands of known NEOs crossing the orbit of Earth, there has been significant scientific interest in developing the capability to deflect an NEO from an impacting trajectory. This thesis applies the ideas of Smoothed Particle Hydrodynamics (SPH) theory to the NEO disruption problem. A simulation package was designed that allows efficacy simulation to be integrated into the mission planning and design process. This is done by applying ideas in high-performance computing (HPC) on the computer graphics processing unit (GPU). Rather than prove a concept through large standalone simulations on a supercomputer, a highly parallel structure allows for flexible, target dependent questions to be resolved. Built around nonclassified data and analysis, this computer package will allow academic institutions to better tackle the issue of NEO mitigation effectiveness.

Parallel goal-oriented adaptive finite element modeling for 3D electromagnetic exploration

NASA Astrophysics Data System (ADS)

Zhang, Y.; Key, K.; Ovall, J.; Holst, M.

2014-12-01

We present a parallel goal-oriented adaptive finite element method for accurate and efficient electromagnetic (EM) modeling of complex 3D structures. An unstructured tetrahedral mesh allows this approach to accommodate arbitrarily complex 3D conductivity variations and a priori known boundaries. The total electric field is approximated by the lowest order linear curl-conforming shape functions and the discretized finite element equations are solved by a sparse LU factorization. Accuracy of the finite element solution is achieved through adaptive mesh refinement that is performed iteratively until the solution converges to the desired accuracy tolerance. Refinement is guided by a goal-oriented error estimator that uses a dual-weighted residual method to optimize the mesh for accurate EM responses at the locations of the EM receivers. As a result, the mesh refinement is highly efficient since it only targets the elements where the inaccuracy of the solution corrupts the response at the possibly distant locations of the EM receivers. We compare the accuracy and efficiency of two approaches for estimating the primary residual error required at the core of this method: one uses local element and inter-element residuals and the other relies on solving a global residual system using a hierarchical basis. For computational efficiency our method follows the Bank-Holst algorithm for parallelization, where solutions are computed in subdomains of the original model. To resolve the load-balancing problem, this approach applies a spectral bisection method to divide the entire model into subdomains that have approximately equal error and the same number of receivers. The finite element solutions are then computed in parallel with each subdomain carrying out goal-oriented adaptive mesh refinement independently. We validate the newly developed algorithm by comparison with controlled-source EM solutions for 1D layered models and with 2D results from our earlier 2D goal oriented adaptive refinement code named MARE2DEM. We demonstrate the performance and parallel scaling of this algorithm on a medium-scale computing cluster with a marine controlled-source EM example that includes a 3D array of receivers located over a 3D model that includes significant seafloor bathymetry variations and a heterogeneous subsurface.

Attentional Selection of Feature Conjunctions Is Accomplished by Parallel and Independent Selection of Single Features.

PubMed

Andersen, Søren K; Müller, Matthias M; Hillyard, Steven A

2015-07-08

Experiments that study feature-based attention have often examined situations in which selection is based on a single feature (e.g., the color red). However, in more complex situations relevant stimuli may not be set apart from other stimuli by a single defining property but by a specific combination of features. Here, we examined sustained attentional selection of stimuli defined by conjunctions of color and orientation. Human observers attended to one out of four concurrently presented superimposed fields of randomly moving horizontal or vertical bars of red or blue color to detect brief intervals of coherent motion. Selective stimulus processing in early visual cortex was assessed by recordings of steady-state visual evoked potentials (SSVEPs) elicited by each of the flickering fields of stimuli. We directly contrasted attentional selection of single features and feature conjunctions and found that SSVEP amplitudes on conditions in which selection was based on a single feature only (color or orientation) exactly predicted the magnitude of attentional enhancement of SSVEPs when attending to a conjunction of both features. Furthermore, enhanced SSVEP amplitudes elicited by attended stimuli were accompanied by equivalent reductions of SSVEP amplitudes elicited by unattended stimuli in all cases. We conclude that attentional selection of a feature-conjunction stimulus is accomplished by the parallel and independent facilitation of its constituent feature dimensions in early visual cortex. The ability to perceive the world is limited by the brain's processing capacity. Attention affords adaptive behavior by selectively prioritizing processing of relevant stimuli based on their features (location, color, orientation, etc.). We found that attentional mechanisms for selection of different features belonging to the same object operate independently and in parallel: concurrent attentional selection of two stimulus features is simply the sum of attending to each of those features separately. This result is key to understanding attentional selection in complex (natural) scenes, where relevant stimuli are likely to be defined by a combination of stimulus features. Copyright © 2015 the authors 0270-6474/15/359912-08$15.00/0.

PCSIM: A Parallel Simulation Environment for Neural Circuits Fully Integrated with Python

PubMed Central

Pecevski, Dejan; Natschläger, Thomas; Schuch, Klaus

2008-01-01

The Parallel Circuit SIMulator (PCSIM) is a software package for simulation of neural circuits. It is primarily designed for distributed simulation of large scale networks of spiking point neurons. Although its computational core is written in C++, PCSIM's primary interface is implemented in the Python programming language, which is a powerful programming environment and allows the user to easily integrate the neural circuit simulator with data analysis and visualization tools to manage the full neural modeling life cycle. The main focus of this paper is to describe PCSIM's full integration into Python and the benefits thereof. In particular we will investigate how the automatically generated bidirectional interface and PCSIM's object-oriented modular framework enable the user to adopt a hybrid modeling approach: using and extending PCSIM's functionality either employing pure Python or C++ and thus combining the advantages of both worlds. Furthermore, we describe several supplementary PCSIM packages written in pure Python and tailored towards setting up and analyzing neural simulations. PMID:19543450

Durham extremely large telescope adaptive optics simulation platform.

PubMed

Basden, Alastair; Butterley, Timothy; Myers, Richard; Wilson, Richard

2007-03-01

Adaptive optics systems are essential on all large telescopes for which image quality is important. These are complex systems with many design parameters requiring optimization before good performance can be achieved. The simulation of adaptive optics systems is therefore necessary to categorize the expected performance. We describe an adaptive optics simulation platform, developed at Durham University, which can be used to simulate adaptive optics systems on the largest proposed future extremely large telescopes as well as on current systems. This platform is modular, object oriented, and has the benefit of hardware application acceleration that can be used to improve the simulation performance, essential for ensuring that the run time of a given simulation is acceptable. The simulation platform described here can be highly parallelized using parallelization techniques suited for adaptive optics simulation, while still offering the user complete control while the simulation is running. The results from the simulation of a ground layer adaptive optics system are provided as an example to demonstrate the flexibility of this simulation platform.

Observation of the Chiral and Achiral Hexatic Phases of Self-assembled Micellar polymers

PubMed Central

Pal, Antara; Kamal, Md. Arif; Raghunathan, V. A.

2016-01-01

We report the discovery of a thermodynamically stable line hexatic (N + 6) phase in a three-dimensional (3D) system made up of self-assembled polymer-like micelles of amphiphilic molecules. The experimentally observed phase transition sequence nematic (N)  N + 6  two-dimensional hexagonal (2D-H) is in good agreement with the theoretical predictions. Further, the present study also brings to light the effect of chirality on the N + 6 phase. In the chiral N + 6 phase the bond-orientational order within each “polymer” bundle is found to be twisted about an axis parallel to the average polymer direction. This structure is consistent with the theoretically envisaged Moiré state, thereby providing the first experimental demonstration of the Moiré structure. In addition to confirming the predictions of fundamental theories of two-dimensional melting, these results are relevant in a variety of situations in chemistry, physics and biology, where parallel packing of polymer-like objects are encountered. PMID:27577927

OWL: A scalable Monte Carlo simulation suite for finite-temperature study of materials

NASA Astrophysics Data System (ADS)

Li, Ying Wai; Yuk, Simuck F.; Cooper, Valentino R.; Eisenbach, Markus; Odbadrakh, Khorgolkhuu

The OWL suite is a simulation package for performing large-scale Monte Carlo simulations. Its object-oriented, modular design enables it to interface with various external packages for energy evaluations. It is therefore applicable to study the finite-temperature properties for a wide range of systems: from simple classical spin models to materials where the energy is evaluated by ab initio methods. This scheme not only allows for the study of thermodynamic properties based on first-principles statistical mechanics, it also provides a means for massive, multi-level parallelism to fully exploit the capacity of modern heterogeneous computer architectures. We will demonstrate how improved strong and weak scaling is achieved by employing novel, parallel and scalable Monte Carlo algorithms, as well as the applications of OWL to a few selected frontier materials research problems. This research was supported by the Office of Science of the Department of Energy under contract DE-AC05-00OR22725.

Riemann-Hilbert technique scattering analysis of metamaterial-based asymmetric 2D open resonators

NASA Astrophysics Data System (ADS)

Kamiński, Piotr M.; Ziolkowski, Richard W.; Arslanagić, Samel

2017-12-01

The scattering properties of metamaterial-based asymmetric two-dimensional open resonators excited by an electric line source are investigated analytically. The resonators are, in general, composed of two infinite and concentric cylindrical layers covered with an infinitely thin, perfect conducting shell that has an infinite axial aperture. The line source is oriented parallel to the cylinder axis. An exact analytical solution of this problem is derived. It is based on the dual-series approach and its transformation to the equivalent Riemann-Hilbert problem. Asymmetric metamaterial-based configurations are found to lead simultaneously to large enhancements of the radiated power and to highly steerable Huygens-like directivity patterns; properties not attainable with the corresponding structurally symmetric resonators. The presented open resonator designs are thus interesting candidates for many scientific and engineering applications where enhanced directional near- and far-field responses, tailored with beam shaping and steering capabilities, are highly desired.

Target-object integration, attention distribution, and object orientation interactively modulate object-based selection.

PubMed

Al-Janabi, Shahd; Greenberg, Adam S

2016-10-01

The representational basis of attentional selection can be object-based. Various studies have suggested, however, that object-based selection is less robust than spatial selection across experimental paradigms. We sought to examine the manner by which the following factors might explain this variation: Target-Object Integration (targets 'on' vs. part 'of' an object), Attention Distribution (narrow vs. wide), and Object Orientation (horizontal vs. vertical). In Experiment 1, participants discriminated between two targets presented 'on' an object in one session, or presented as a change 'of' an object in another session. There was no spatial cue-thus, attention was initially focused widely-and the objects were horizontal or vertical. We found evidence of object-based selection only when targets constituted a change 'of' an object. Additionally, object orientation modulated the sign of object-based selection: We observed a same-object advantage for horizontal objects, but a same-object cost for vertical objects. In Experiment 2, an informative cue preceded a single target presented 'on' an object or as a change 'of' an object (thus, attention was initially focused narrowly). Unlike in Experiment 1, we found evidence of object-based selection independent of target-object integration. We again found that the sign of selection was modulated by the objects' orientation. This result may reflect a meridian effect, which emerged due to anisotropies in the cortical representations when attention is oriented endogenously. Experiment 3 revealed that object orientation did not modulate object-based selection when attention was oriented exogenously. Our findings suggest that target-object integration, attention distribution, and object orientation modulate object-based selection, but only in combination.

Monte Carlo modelling the dosimetric effects of electrode material on diamond detectors.

PubMed

Baluti, Florentina; Deloar, Hossain M; Lansley, Stuart P; Meyer, Juergen

2015-03-01

Diamond detectors for radiation dosimetry were modelled using the EGSnrc Monte Carlo code to investigate the influence of electrode material and detector orientation on the absorbed dose. The small dimensions of the electrode/diamond/electrode detector structure required very thin voxels and the use of non-standard DOSXYZnrc Monte Carlo model parameters. The interface phenomena was investigated by simulating a 6 MV beam and detectors with different electrode materials, namely Al, Ag, Cu and Au, with thickens of 0.1 µm for the electrodes and 0.1 mm for the diamond, in both perpendicular and parallel detector orientation with regards to the incident beam. The smallest perturbations were observed for the parallel detector orientation and Al electrodes (Z = 13). In summary, EGSnrc Monte Carlo code is well suited for modelling small detector geometries. The Monte Carlo model developed is a useful tool to investigate the dosimetric effects caused by different electrode materials. To minimise perturbations cause by the detector electrodes, it is recommended that the electrodes should be made from a low-atomic number material and placed parallel to the beam direction.

Metaphysical Underdetermination and Logical Determination: the Case of Quantum Mechanics

NASA Astrophysics Data System (ADS)

Arenhart, Jonas R. B.

2014-03-01

The `underdetermination of metaphysics by the physics' is the thesis that our best scientific theories do not uniquely determine their ontologies. Non-relativistic quantum mechanics is famously thought to exemplify this kind of underdetermination: it may be seen as compatible with both an ontology of individual objects and with an ontology of non-individual objects. A possible way out of the dilema thus created consists in adopting some version of Ontic Structural Realism (OSR), a view according to which the metaphysically relevant aspect of the theory is its structure, not the nature of the objects dealt with. According to OSR, particular objects may be dispensed with (eliminated or re-conceptualized) in favor of the structure of the theory. In this paper we shall argue that the underdetermination of metaphysics by the physics is a consequence of a too strict naturalism in ontology. As a result, when a mitigated ontological naturalism is taken into account, underdetermination does not appear to have such dark consequences for object-oriented ontologies in quantum mechanics.

Qualitative assessment of precocious puberty-related user-created contents on YouTube.

PubMed

Nam, Hyo-Kyoung; Bang, Soo Min; Rhie, Young Jun; Park, Sang Hee; Lee, Kee-Hyoung

2015-09-01

User-created content (UCC) has provided a considerable amount of medical information and become an important source. We aimed to evaluate the quality and scientific accuracy of precocious puberty-related UCC on YouTube. The keywords "precocious puberty", "early puberty", "sexual precocity", and "precocity" were searched for on YouTube during June and July 2014. More than 1,500 UCC matched the keywords. According to the information provider, UCC was classified as medical, oriental, or commercial & others. We evaluated the quality and scientific accuracy of the information provided in UCC using the DISCERN instrument and information scores, respectively. We selected 51 UCC, which were categorized into three types: medical (n=17), oriental (n=17), or commercial & others (n=17). The overall quality score for medical UCC (3.4) was significantly higher relative to those of oriental and commercial & others UCC (2.8 and 2.3, respectively) (P<0.001). In the assessment of scientific accuracy, the mean information score for medical UCC (30.7) was significantly higher than those of oriental and commercial & others UCC (15.9 and 5.1, respectively) (P<0.001). The mean duration of oriental UCC was the longest (P<0.001), however, it was viewed less frequently among them (P=0.086). The quality and accuracy of precocious puberty-related health information in UCC were variable and often unreliable. The overall quality of UCC regarding precocious puberty was moderate. Only medical UCC provided scientifically accurate information. As UCC becomes a popular source of health information, it is important to provide reliable, scientifically accurate information.

Qualitative assessment of precocious puberty-related user-created contents on YouTube

PubMed Central

Nam, Hyo-Kyoung; Bang, Soo Min; Rhie, Young Jun; Park, Sang Hee

2015-01-01

Purpose User-created content (UCC) has provided a considerable amount of medical information and become an important source. We aimed to evaluate the quality and scientific accuracy of precocious puberty-related UCC on YouTube. Methods The keywords "precocious puberty", "early puberty", "sexual precocity", and "precocity" were searched for on YouTube during June and July 2014. More than 1,500 UCC matched the keywords. According to the information provider, UCC was classified as medical, oriental, or commercial & others. We evaluated the quality and scientific accuracy of the information provided in UCC using the DISCERN instrument and information scores, respectively. Results We selected 51 UCC, which were categorized into three types: medical (n=17), oriental (n=17), or commercial & others (n=17). The overall quality score for medical UCC (3.4) was significantly higher relative to those of oriental and commercial & others UCC (2.8 and 2.3, respectively) (P<0.001). In the assessment of scientific accuracy, the mean information score for medical UCC (30.7) was significantly higher than those of oriental and commercial & others UCC (15.9 and 5.1, respectively) (P<0.001). The mean duration of oriental UCC was the longest (P<0.001), however, it was viewed less frequently among them (P=0.086). Conclusion The quality and accuracy of precocious puberty-related health information in UCC were variable and often unreliable. The overall quality of UCC regarding precocious puberty was moderate. Only medical UCC provided scientifically accurate information. As UCC becomes a popular source of health information, it is important to provide reliable, scientifically accurate information. PMID:26512350

A severe capacity limit in the consolidation of orientation information into visual short-term memory.

PubMed

Becker, Mark W; Miller, James R; Liu, Taosheng

2013-04-01

Previous research has suggested that two color patches can be consolidated into visual short-term memory (VSTM) via an unlimited parallel process. Here we examined whether the same unlimited-capacity parallel process occurs for two oriented grating patches. Participants viewed two gratings that were presented briefly and masked. In blocks of trials, the gratings were presented either simultaneously or sequentially. In Experiments 1 and 2, the presentation of the stimuli was followed by a location cue that indicated the grating on which to base one's response. In Experiment 1, participants responded whether the target grating was oriented clockwise or counterclockwise with respect to vertical. In Experiment 2, participants indicated whether the target grating was oriented along one of the cardinal directions (vertical or horizontal) or was obliquely oriented. Finally, in Experiment 3, the location cue was replaced with a third grating that appeared at fixation, and participants indicated whether either of the two test gratings matched this probe. Despite the fact that these responses required fairly coarse coding of the orientation information, across all methods of responding we found superior performance for sequential over simultaneous presentations. These findings suggest that the consolidation of oriented gratings into VSTM is severely limited in capacity and differs from the consolidation of color information.

The effect of spatial orientation on detecting motion trajectories in noise.

PubMed

Pavan, Andrea; Casco, Clara; Mather, George; Bellacosa, Rosilari M; Cuturi, Luigi F; Campana, Gianluca

2011-09-15

A series of experiments investigated the extent to which the spatial orientation of a signal line affects discrimination of its trajectory from the random trajectories of background noise lines. The orientation of the signal line was either parallel (iso-) or orthogonal (ortho-) to its motion direction and it was identical in all respects to the noise (orientation, length and speed) except for its motion direction, rendering the signal line indistinguishable from the noise on a frame-to-frame basis. We found that discrimination of ortho-trajectories was generally better than iso-trajectories. Discrimination of ortho-trajectories was largely immune to the effects of spatial jitter in the trajectory, and to variations in step size and line-length. Discrimination of iso-trajectories was reliable provided that step-size was not too short and did not exceed line length, and that the trajectory was straight. The new result that trajectory discrimination in moving line elements is modulated by line orientation suggests that ortho- and iso-trajectory discrimination rely upon two distinct mechanisms: iso-motion discrimination involves a 'motion-streak' process that combines motion information with information about orientation parallel to the motion trajectory, while ortho-motion discrimination involves extended trajectory facilitation in a network of receptive fields with orthogonal orientation tuning. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Cassini/Huygens Doppler Wind Experiment: Results from the Titan Descent

NASA Technical Reports Server (NTRS)

Bird, M. K.; Dutta-Roy, R.; Allison, M.; Asmar, S. W.; Atkinson, D. H.; Edenhofer, P.; Plettemeier, D.; Tyler, G. L.

2005-01-01

The primary objective of the Doppler Wind Experiment (DWE), one of the six scientific investigations comprising the payload of the ESA Huygens Probe, is a determination of the wind velocity in Titan's atmosphere. Measurements of the Doppler shift of the S-band (2040 MHz) carrier signal to the Cassini Orbiter and to Earth were recorded during the Probe descent in order to deduce wind-induced motion of the Probe to an accuracy better than 1 m s-1. An experiment with the same scientific goal was performed with the Galileo Probe at Jupiter. Analogous to the Galileo experience, it was anticipated that the frequency of the Huygens radio signal could be measured on Earth to obtain an additional component of the horizontal winds. Specific secondary science objectives of DWE include measurements of: (a) Doppler fluctuations to determine the turbulence spectrum and possible wave activity in the Titan atmosphere; (b) Doppler and signal level modulation to monitor Probe descent dynamics (e.g., spinrate/spinphase, parachute swing); (c) Probe coordinates and orientation during descent and after impact on Titan.

Method for selectively orienting induced fractures in subterranean earth formations

DOEpatents

Shuck, Lowell Z.

1977-02-01

The orientation of hydraulically-induced fractures in relatively deep subterranean earth formations is normally confined to vertical projections along a plane parallel to the maximum naturally occurring (tectonic) compressive stress field. It was found that this plane of maximum compressive stress may be negated and, in effect, re-oriented in a plane projecting generally orthogonal to the original tectonic stress plane by injecting liquid at a sufficiently high pressure into a wellbore fracture oriented in a plane parallel to the plane of tectonic stress for the purpose of stressing the surrounding earth formation in a plane generally orthogonal to the plane of tectonic stress. With the plane of maximum compressive stress re-oriented due to the presence of the induced compressive stress, liquid under pressure is injected into a second wellbore disposed within the zone influenced by the induced compressive stress but at a location in the earth formation laterally spaced from the fracture in the first wellbore for effecting a fracture in the second wellbore along a plane generally orthogonal to the fracture in the first wellbore.

Production of yarns composed of oriented nanofibers for ophthalmological implants

NASA Astrophysics Data System (ADS)

Shynkarenko, A.; Klapstova, A.; Krotov, A.; Moucka, M.; Lukas, D.

2017-10-01

Parallelized nanofibrous structures are commonly used in medical sector, especially for the ophthalmological implants. In this research self-fabricated device is tested for improved collection and twisting of the parallel nanofibers. Previously manual techniques are used to collect the nanofibers and then twist is given, where as in our device different parameters can be optimized to obtained parallel nanofibers and further twisting can be given. The device is used to bring automation to the technique of achieving parallel fibrous structures for medical applications.

Noncontact orientation of objects in three-dimensional space using magnetic levitation

PubMed Central

Subramaniam, Anand Bala; Yang, Dian; Yu, Hai-Dong; Nemiroski, Alex; Tricard, Simon; Ellerbee, Audrey K.; Soh, Siowling; Whitesides, George M.

2014-01-01

This paper describes several noncontact methods of orienting objects in 3D space using Magnetic Levitation (MagLev). The methods use two permanent magnets arranged coaxially with like poles facing and a container containing a paramagnetic liquid in which the objects are suspended. Absent external forcing, objects levitating in the device adopt predictable static orientations; the orientation depends on the shape and distribution of mass within the objects. The orientation of objects of uniform density in the MagLev device shows a sharp geometry-dependent transition: an analytical theory rationalizes this transition and predicts the orientation of objects in the MagLev device. Manipulation of the orientation of the levitating objects in space is achieved in two ways: (i) by rotating and/or translating the MagLev device while the objects are suspended in the paramagnetic solution between the magnets; (ii) by moving a small external magnet close to the levitating objects while keeping the device stationary. Unlike mechanical agitation or robotic selection, orienting using MagLev is possible for objects having a range of different physical characteristics (e.g., different shapes, sizes, and mechanical properties from hard polymers to gels and fluids). MagLev thus has the potential to be useful for sorting and positioning components in 3D space, orienting objects for assembly, constructing noncontact devices, and assembling objects composed of soft materials such as hydrogels, elastomers, and jammed granular media. PMID:25157136

Noncontact orientation of objects in three-dimensional space using magnetic levitation.

PubMed

Subramaniam, Anand Bala; Yang, Dian; Yu, Hai-Dong; Nemiroski, Alex; Tricard, Simon; Ellerbee, Audrey K; Soh, Siowling; Whitesides, George M

2014-09-09

This paper describes several noncontact methods of orienting objects in 3D space using Magnetic Levitation (MagLev). The methods use two permanent magnets arranged coaxially with like poles facing and a container containing a paramagnetic liquid in which the objects are suspended. Absent external forcing, objects levitating in the device adopt predictable static orientations; the orientation depends on the shape and distribution of mass within the objects. The orientation of objects of uniform density in the MagLev device shows a sharp geometry-dependent transition: an analytical theory rationalizes this transition and predicts the orientation of objects in the MagLev device. Manipulation of the orientation of the levitating objects in space is achieved in two ways: (i) by rotating and/or translating the MagLev device while the objects are suspended in the paramagnetic solution between the magnets; (ii) by moving a small external magnet close to the levitating objects while keeping the device stationary. Unlike mechanical agitation or robotic selection, orienting using MagLev is possible for objects having a range of different physical characteristics (e.g., different shapes, sizes, and mechanical properties from hard polymers to gels and fluids). MagLev thus has the potential to be useful for sorting and positioning components in 3D space, orienting objects for assembly, constructing noncontact devices, and assembling objects composed of soft materials such as hydrogels, elastomers, and jammed granular media.

Layperson's preference regarding orientation of the transverse occlusal plane and commissure line from the frontal perspective.

PubMed

Silva, Bruno Pereira; Jiménez-Castellanos, Emilio; Finkel, Sivan; Macias, Inmaculada Redondo; Chu, Stephen J

2017-04-01

Facial asymmetries in features such as lip commissure and interpupillary plane canting have been described as common conditions affecting smile esthetics. When presented with these asymmetries, the clinician must choose the reference line with which to orient the transverse occlusal plane of the planned dental restorations. The purpose of the online survey described in this study was to determine lay preferences regarding the transverse occlusal plane orientation in faces that display a cant of the commissure line viewed from the frontal perspective. From a digitally created symmetrical facial model with the transverse occlusal plane and commissure line parallel to the interpupillary line (horizontal) and a model constructed in a previous study (control), a new facial model was created with 3 degrees of cant of the commissure line. Three digital tooth mountings were designed with different transverse occlusal plane orientations: parallel to the interpupillary line (A), parallel to the commissure line (B), and the mean angulation plane formed between the interpupillary and commissure line (C), resulting in a total of 4 images. All images, including the control, were organized into 6 pairs and evaluated by 247 selected laypersons through an online Web site survey. Each participant was asked to choose the more attractive face from each of the 6 pairs of images. The control image was preferred by 72.9% to 74.5% of the participants compared with the other 3 images, all of which represented a commissure line cant. Among the 3 pairs which represent a commissure line cant, 59.1% to 61.1% preferred a transverse plane of occlusion cant (B and C) compared with a plane of occlusion parallel to the interpupillary, line and 61.1% preferred a plane of occlusion parallel to the commissure line (B) compared with the mean angulation plane (C). Laypeople prefer faces with a commissure line and transverse occlusal plane parallel to the horizontal plane or horizon. When faces present a commissure line cant, laypeople prefer a transverse occlusal plane with a similar and coincident cant. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Environmental Degradation of Materials: Surface Chemistry Related to Stress Corrosion Cracking

NASA Technical Reports Server (NTRS)

Schwarz, J. A.

1985-01-01

Parallel experiments have been performed in order to develop a comprehensive model for stress cracking (SCC) in structural materials. The central objective is to determine the relationship between the activity and selectivity of the microstructure of structural materials to their dissolution kinetics and experimentally measured SCC kinetics. Zinc was chosen as a prototype metal system. The SCC behavior of two oriented single-crystal disks of zinc in a chromic oxide/sodium sulfate solution (Palmerton solution) were determined. It was found that: (1) the dissolution rate is strongly (hkil)-dependent and proportional to the exposure time in the aggressive environment; and (2) a specific slip system is selectively active to dissolution under applied stress and this slip line controls crack initiation and propagation. As a precursor to potential microgrvity experiments, electrophoretic mobility measurements of zinc particles were obtained in solutions of sodium sulfate (0.0033 M) with concentrations of dissolved oxygen from 2 to 8 ppm. The equilibrium distribution of exposed oriented planes as well as their correlation will determine the particle mobility.

Project TIMS (Teaching Integrated Math/Science)

NASA Technical Reports Server (NTRS)

Edwards, Leo, Jr.

1993-01-01

The goal of this project is to increase the scientific knowledge and appreciation bases and skills of pre-service and in-service middle school teachers, so as to impact positively on teaching, learning, and student retention. This report lists the objectives and summarizes the progress thus far. Included is the working draft of the TIMS (Teaching Integrated Math/Science) curriculum outline. Seven of the eight instructional subject-oriented modules are also included. The modules include informative materials and corresponding questions and educational activities in a textbook format. The subjects included here are the universe and stars; the sun and its place in the universe; our solar system; astronomical instruments and scientific measurements; the moon and eclipses; the earth's atmosphere: its nature and composition; and the earth: directions, time, and seasons. The module not included regards winds and circulation.

Magnetically-assembled micro/mesopixels exhibiting light intensity enhancement in the (012) planes of fish guanine crystals

NASA Astrophysics Data System (ADS)

Chikashige, T.; Iwasaka, M.

2018-05-01

In this study, a new method was investigated to form light-reflecting dots at the micrometer scale using the magnetic orientations of biogenic guanine crystals obtained from fish skin and scales. The crystal platelets, possessing average dimensions of 5 μm×20 μm×100 nm, were dispersed in water and observed during exposure to vertical magnetic fields up to 5 T. The magnetic field direction was parallel to Earth's gravity, and allowed the narrowest edges of the crystals to be observed at the micrometer scale for the first time. The magnetic orientation process was initiated under conditions where the crystal platelets in water were laid on a glass substrate or where the platelets had random orientations. In the former case, the crystal platelets followed a two-stage magnetic orientation process where, in the first step, the platelet widths were aligned in the magnetic field direction. The second step required rotation of the ˜20-μm-long plates with respect to the Earth's gravity, where application of a 5 T magnetic field enabled their orientation. Real-time images of the magnetically aligning platelets provided new evidence that the crystal platelets also emitted reflected light from a very narrow window at two crystal planes (i.e., (0 1 ¯ 2 ¯ ) and (0 1 ¯ 2 )). In the latter case with random platelet orientation, spatially-condensed light-reflecting dots appeared while the guanine crystal platelets were floating and maintaining their orientation. The technique developed for controlling light-reflecting microscale objects in an aqueous medium can be applied to produce a type of microfluidic optical tool.

Trace: a high-throughput tomographic reconstruction engine for large-scale datasets.

PubMed

Bicer, Tekin; Gürsoy, Doğa; Andrade, Vincent De; Kettimuthu, Rajkumar; Scullin, William; Carlo, Francesco De; Foster, Ian T

2017-01-01

Modern synchrotron light sources and detectors produce data at such scale and complexity that large-scale computation is required to unleash their full power. One of the widely used imaging techniques that generates data at tens of gigabytes per second is computed tomography (CT). Although CT experiments result in rapid data generation, the analysis and reconstruction of the collected data may require hours or even days of computation time with a medium-sized workstation, which hinders the scientific progress that relies on the results of analysis. We present Trace, a data-intensive computing engine that we have developed to enable high-performance implementation of iterative tomographic reconstruction algorithms for parallel computers. Trace provides fine-grained reconstruction of tomography datasets using both (thread-level) shared memory and (process-level) distributed memory parallelization. Trace utilizes a special data structure called replicated reconstruction object to maximize application performance. We also present the optimizations that we apply to the replicated reconstruction objects and evaluate them using tomography datasets collected at the Advanced Photon Source. Our experimental evaluations show that our optimizations and parallelization techniques can provide 158× speedup using 32 compute nodes (384 cores) over a single-core configuration and decrease the end-to-end processing time of a large sinogram (with 4501 × 1 × 22,400 dimensions) from 12.5 h to <5 min per iteration. The proposed tomographic reconstruction engine can efficiently process large-scale tomographic data using many compute nodes and minimize reconstruction times.

Rapid assessment of crystal orientation in semi-crystalline polymer films using rotational zone annealing and impact of orientation on mechanical properties

DOE PAGES

Ye, Changhuai; Wang, Chao; Wang, Jing; ...

2017-08-17

Crystal orientation in semi-crystalline polymers tends to enhance their performance, such as increased yield strength and modulus, along the orientation direction. Zone annealing (ZA) orients the crystal lamellae through a sharp temperature gradient that effectively directs the crystal growth, but the sweep rate (V ZA) of this gradient significantly impacts the extent of crystal orientation. Here in this work, we demonstrate rotational zone annealing (RZA) as an efficient method to elucidate the influence of V ZA on the crystal morphology of thin films in a single experiment using isotactic poly(1-butene), PB-1, as a model semi-crystalline polymer. These RZA results aremore » confirmed using standard, serial linear ZA to tune the structure from an almost unidirectional oriented morphology to weakly oriented spherulites. The overall crystallinity is only modestly changed in comparison to isothermal crystallization (maximum of 55% from ZA vs. 48% for isothermal crystallization). However, the average grain size increases and the spherulites become anisotropic from ZA. Due to these structural changes, the Young's modulus of the oriented films, both parallel and perpendicular to the spherulite orientation direction, is significantly increased by ZA. The modulus does become anisotropic after ZA due to the directionality in the crystal structure, with more than a threefold increase in the modulus parallel to the orientation direction for the highest oriented film in comparison to the modulus from isothermal crystallization. Lastly, RZA enables rapid identification of conditions to maximize orientation of crystals in thin polymer films, which could find utility in determining conditions to improve crystallinity and performance in organic electronics.« less

Rapid assessment of crystal orientation in semi-crystalline polymer films using rotational zone annealing and impact of orientation on mechanical properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Changhuai; Wang, Chao; Wang, Jing

Crystal orientation in semi-crystalline polymers tends to enhance their performance, such as increased yield strength and modulus, along the orientation direction. Zone annealing (ZA) orients the crystal lamellae through a sharp temperature gradient that effectively directs the crystal growth, but the sweep rate (V ZA) of this gradient significantly impacts the extent of crystal orientation. Here in this work, we demonstrate rotational zone annealing (RZA) as an efficient method to elucidate the influence of V ZA on the crystal morphology of thin films in a single experiment using isotactic poly(1-butene), PB-1, as a model semi-crystalline polymer. These RZA results aremore » confirmed using standard, serial linear ZA to tune the structure from an almost unidirectional oriented morphology to weakly oriented spherulites. The overall crystallinity is only modestly changed in comparison to isothermal crystallization (maximum of 55% from ZA vs. 48% for isothermal crystallization). However, the average grain size increases and the spherulites become anisotropic from ZA. Due to these structural changes, the Young's modulus of the oriented films, both parallel and perpendicular to the spherulite orientation direction, is significantly increased by ZA. The modulus does become anisotropic after ZA due to the directionality in the crystal structure, with more than a threefold increase in the modulus parallel to the orientation direction for the highest oriented film in comparison to the modulus from isothermal crystallization. Lastly, RZA enables rapid identification of conditions to maximize orientation of crystals in thin polymer films, which could find utility in determining conditions to improve crystallinity and performance in organic electronics.« less

The Role of Graphic Orientations in Children's Drawings of Familiar and Novel Objects at Rest and in Motion.

ERIC Educational Resources Information Center

Ives, William; Rovet, Joanne

1979-01-01

Reports three experiments which investigate: whether familiar objects have standard graphic orientations (Experiment 1); the relationship between use of object orientations and more conventional methods in depicting familiar objects in motion (Experiment 2); and whether orientations are used differently in novel objects whose only defining feature…

Statistical Image Properties in Works from the Prinzhorn Collection of Artists with Schizophrenia

PubMed Central

Henemann, Gudrun Maria; Brachmann, Anselm; Redies, Christoph

2017-01-01

The Prinzhorn Collection preserves and exhibits thousands of visual artworks by patients who were diagnosed to suffer from mental disease. From this collection, we analyzed 1,256 images by 14 artists who were diagnosed with dementia praecox or schizophrenia. Six objective statistical properties that have been used previously to characterize visually aesthetic images were calculated. These properties reflect features of formal image composition, such as the complexity and distribution of oriented luminance gradients and edges, as well as Fourier spectral properties. Results for the artists with schizophrenia were compared to artworks from three public art collections of paintings and drawings that include highly acclaimed artworks as well as artworks of lesser artistic claim (control artworks). Many of the patients’ works did not differ from these control images. However, the artworks of 6 of the 14 artists with schizophrenia possess image properties that deviate from the range of values obtained for the control artworks. For example, the artworks of four of the patients are characterized by a relative dominance of specific edge orientations in their images (low first-order entropy of edge orientations). Three patients created artworks with a relatively high ratio of fine detail to coarse structure (high slope of the Fourier spectrum). In conclusion, the present exploratory study opens novel perspectives for the objective scientific investigation of visual artworks that were created by persons who suffer from schizophrenia. PMID:29312011

Accessing and visualizing scientific spatiotemporal data

NASA Technical Reports Server (NTRS)

Katz, Daniel S.; Bergou, Attila; Berriman, G. Bruce; Block, Gary L.; Collier, Jim; Curkendall, David W.; Good, John; Husman, Laura; Jacob, Joseph C.; Laity, Anastasia;

The psychology of meta-ethics: exploring objectivism.

PubMed

Goodwin, Geoffrey P; Darley, John M

2008-03-01

How do lay individuals think about the objectivity of their ethical beliefs? Do they regard them as factual and objective, or as more subjective and opinion-based, and what might predict such differences? In three experiments, we set out a methodology for assessing the perceived objectivity of ethical beliefs, and use it to document several novel findings. Experiment 1 showed that individuals tend to regard ethical statements as clearly more objective than social conventions and tastes, and almost as objective as scientific facts. Yet, there was considerable variation in objectivism, both across different ethical statements, and across individuals. The extent to which individuals treat ethical beliefs as objective was predicted by the way they grounded their ethical systems. Groundings which emphasize the religious, pragmatic, and self-identity underpinnings of ethical belief each independently predicted greater ethical objectivity. Experiment 2 replicated and extended these findings with a refined measure of ethical objectivism. Experiment 3 demonstrated the robustness of the religious grounding of ethics, and differentiates it from mere religious belief and from political orientation. The results shed light on the nature of ethical belief, and have implications for the resolution of ethical disputes.

Flexible feature-space-construction architecture and its VLSI implementation for multi-scale object detection

NASA Astrophysics Data System (ADS)

Luo, Aiwen; An, Fengwei; Zhang, Xiangyu; Chen, Lei; Huang, Zunkai; Jürgen Mattausch, Hans

2018-04-01

Feature extraction techniques are a cornerstone of object detection in computer-vision-based applications. The detection performance of vison-based detection systems is often degraded by, e.g., changes in the illumination intensity of the light source, foreground-background contrast variations or automatic gain control from the camera. In order to avoid such degradation effects, we present a block-based L1-norm-circuit architecture which is configurable for different image-cell sizes, cell-based feature descriptors and image resolutions according to customization parameters from the circuit input. The incorporated flexibility in both the image resolution and the cell size for multi-scale image pyramids leads to lower computational complexity and power consumption. Additionally, an object-detection prototype for performance evaluation in 65 nm CMOS implements the proposed L1-norm circuit together with a histogram of oriented gradients (HOG) descriptor and a support vector machine (SVM) classifier. The proposed parallel architecture with high hardware efficiency enables real-time processing, high detection robustness, small chip-core area as well as low power consumption for multi-scale object detection.

Scrutinizing Immutability: Research on Sexual Orientation and U.S. Legal Advocacy for Sexual Minorities.

PubMed

Diamond, Lisa M; Rosky, Clifford J

2016-01-01

We review scientific research and legal authorities to argue that the immutability of sexual orientation should no longer be invoked as a foundation for the rights of individuals with same-sex attractions and relationships (i.e., sexual minorities). On the basis of scientific research as well as U.S. legal rulings regarding lesbian, gay, and bisexual (LGB) rights, we make three claims: First, arguments based on the immutability of sexual orientation are unscientific, given what we now know from longitudinal, population-based studies of naturally occurring changes in the same-sex attractions of some individuals over time. Second, arguments based on the immutability of sexual orientation are unnecessary, in light of U.S. legal decisions in which courts have used grounds other than immutability to protect the rights of sexual minorities. Third, arguments about the immutability of sexual orientation are unjust, because they imply that same-sex attractions are inferior to other-sex attractions, and because they privilege sexual minorities who experience their sexuality as fixed over those who experience their sexuality as fluid. We conclude that the legal rights of individuals with same-sex attractions and relationships should not be framed as if they depend on a certain pattern of scientific findings regarding sexual orientation.

The emergence of the ecological mind in Hua-Yen/Kegon Buddhism and Jungian psychology.

PubMed

Cambray, Joe

2017-02-01

The complexity associated with deep interconnectedness in nature is beginning to be articulated and elaborated in the field of ecological studies. While some parallels to the psyche have been made and the field of Eco-psychology has been developing, Jung's explicit contribution by way of the image of rhizomes has not been considered in detail. Philosopher Gilles Deleuze acknowledges borrowing the term from Jung, though he disagreed with Jung's Empedoclean use of the term. The paper presents some fundamental properties of rhizomes along with contemporary scientific research on mycorrhizal (fungal) networks. Comparisons are made, first with classical symbolic forms, demonstrating some overlap but also some differences. Then comparison of rhizomal networks is made to those found both in mammalian brains and in recent images of the 'cosmic web'. While no hard conclusions can be drawn from these images, their remarkable similarities are suggestive of a need to reconsider what is meant by 'intelligence'. The cosmic web is one of the largest structures in the known universe (clusters of galaxies which form into filaments and walls) with empty spaces in between. Exploration of the structure of this web leads to a discussion of dark matter and dark energy, current hot topics in science, probing into the mysteries of our 'Big-Bang' cosmology. An additional comparison of the emerging image of the universe as a whole with the ancient Chinese Buddhist cosmological vision from the Hua-Yen School (Kegon in Japan) again reveals profound parallels. The potential convergence of aspects of subjective, or meditative, explorations with objective scientific constructions is striking and offers links between East and West, as well as potential confirmation of the objective aspects of empathy. © 2017, The Society of Analytical Psychology.

An object-oriented description method of EPMM process

NASA Astrophysics Data System (ADS)

Jiang, Zuo; Yang, Fan

2017-06-01

In order to use the object-oriented mature tools and language in software process model, make the software process model more accord with the industrial standard, it’s necessary to study the object-oriented modelling of software process. Based on the formal process definition in EPMM, considering the characteristics that Petri net is mainly formal modelling tool and combining the Petri net modelling with the object-oriented modelling idea, this paper provides this implementation method to convert EPMM based on Petri net into object models based on object-oriented description.

FastQuery: A Parallel Indexing System for Scientific Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chou, Jerry; Wu, Kesheng; Prabhat,

2011-07-29

Modern scientific datasets present numerous data management and analysis challenges. State-of-the- art index and query technologies such as FastBit can significantly improve accesses to these datasets by augmenting the user data with indexes and other secondary information. However, a challenge is that the indexes assume the relational data model but the scientific data generally follows the array data model. To match the two data models, we design a generic mapping mechanism and implement an efficient input and output interface for reading and writing the data and their corresponding indexes. To take advantage of the emerging many-core architectures, we also developmore » a parallel strategy for indexing using threading technology. This approach complements our on-going MPI-based parallelization efforts. We demonstrate the flexibility of our software by applying it to two of the most commonly used scientific data formats, HDF5 and NetCDF. We present two case studies using data from a particle accelerator model and a global climate model. We also conducted a detailed performance study using these scientific datasets. The results show that FastQuery speeds up the query time by a factor of 2.5x to 50x, and it reduces the indexing time by a factor of 16 on 24 cores.« less

[CMACPAR an modified parallel neuro-controller for control processes].

PubMed

Ramos, E; Surós, R

1999-01-01

CMACPAR is a Parallel Neurocontroller oriented to real time systems as for example Control Processes. Its characteristics are mainly a fast learning algorithm, a reduced number of calculations, great generalization capacity, local learning and intrinsic parallelism. This type of neurocontroller is used in real time applications required by refineries, hydroelectric centers, factories, etc. In this work we present the analysis and the parallel implementation of a modified scheme of the Cerebellar Model CMAC for the n-dimensional space projection using a mean granularity parallel neurocontroller. The proposed memory management allows for a significant memory reduction in training time and required memory size.

Parietal and frontal object areas underlie perception of object orientation in depth.

PubMed

Niimi, Ryosuke; Saneyoshi, Ayako; Abe, Reiko; Kaminaga, Tatsuro; Yokosawa, Kazuhiko

2011-05-27

Recent studies have shown that the human parietal and frontal cortices are involved in object image perception. We hypothesized that the parietal/frontal object areas play a role in differentiating the orientations (i.e., views) of an object. By using functional magnetic resonance imaging, we compared brain activations while human observers differentiated between two object images in depth-orientation (orientation task) and activations while they differentiated the images in object identity (identity task). The left intraparietal area, right angular gyrus, and right inferior frontal areas were activated more for the orientation task than for the identity task. The occipitotemporal object areas, however, were activated equally for the two tasks. No region showed greater activation for the identity task. These results suggested that the parietal/frontal object areas encode view-dependent visual features and underlie object orientation perception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Serial consolidation of orientation information into visual short-term memory.

PubMed

Liu, Taosheng; Becker, Mark W

2013-06-01

Previous research suggests that there is a limit to the rate at which items can be consolidated in visual short-term memory (VSTM). This limit could be due to either a serial or a limited-capacity parallel process. Historically, it has proven difficult to distinguish between these two types of processes. In the present experiment, we took a novel approach that allowed us to do so. Participants viewed two oriented gratings either sequentially or simultaneously and reported one of the gratings' orientation via method of adjustment. Performance was worse for the simultaneous than for the sequential condition. We fit the data with a mixture model that assumes performance is limited by a noisy memory representation plus random guessing. Critically, the serial and limited-capacity parallel processes made distinct predictions regarding the model's guessing and memory-precision parameters. We found strong support for a serial process, which implies that one can consolidate only a single orientation into VSTM at a time.

Compression-Induced Conformation and Orientation Changes in an n-Alkane Monolayer on a Au(111) Surface.

PubMed

Endo, Osamu; Nakamura, Masashi; Amemiya, Kenta; Ozaki, Hiroyuki

2017-04-25

The influence of the preparation method and adsorbed amount of n-tetratetracontane (n-C 44 H 90 ) on its orientation in a monolayer on the Au(111) surface is studied by near carbon K-edge X-ray absorption fine structure spectroscopy (C K-NEXAFS), scanning tunneling microscopy (STM) under ultrahigh vacuum, and infrared reflection-absorption spectroscopy (IRAS) at the electrochemical interface in sulfuric acid solution. The n-C 44 H 90 molecules form self-assembled lamellar structures with the chain axis parallel to the surface, as observed by STM. For small amounts adsorbed, the carbon plane is parallel to the surface (flat-on orientation). An increase in the adsorbed amount by ∼10-20% induces compression of the lamellar structure either along the lamellar axis or alkyl chain axis. The compressed molecular arrangement is observed by STM, and induced conformation and orientation changes are confirmed by in situ IRAS and C K-NEXAFS.

Stress rotation along pre-Cenozoic basement structures

NASA Astrophysics Data System (ADS)

Reiter, K.; Heidbach, O.; Henk, A.

2017-12-01

The in-situ stress state of the Earth's crust is under investigation since decades for both, scientific and economic purposes. Several methods have been established to indicate the contemporary orientation of the maximum compressive horizontal stress (SHmax). It is assumed that the same forces that drive plate motion are the first order stress sources and one could presume that SHmax is always parallel to plate motion, which is the case for some regions. However, deviations from this general trend occur in many regions. Therefore, second and third order sources of stress have been identified that potentially cause regional and local stress rotation with respect to the long wave-length trend imposed by plate tectonic forces. One group of such subordinate stress sources are lateral heterogeneities based on structures, petrothermal or petrophysical properties. The World Stress Map (WSM) project compiles systematically data records of the present day SHmax orientation. The increasing amount of stress orientation data allows to investigate areas with consistent stress rotation, divergent to the regional stress pattern. In our work we analyse the stress pattern variability and its causes beneath Germany. In the Molasse Basin in the Alpine foreland the SHmax orientation is perpendicular to the Alpine front as a consequence of gravitational potential energy of the orogen. SHmax is oriented in N-S direction in the central Alpine foreland and within the North German Basin. Between both, within the Mid-German Crystalline High, SHmax is divergent oriented in SE-NW direction. Neither gravitational potential energy nor petrothermal effects can be indicated as stress source. But when comparing the stress pattern with the Variscan basement structures it is obvious that SHmax is perpendicular oriented to this Palaeozoic basement structures. Therefore, petrophysical heterogeneities can be expected as reason for the observed stress rotation. Two assumptions can be made for the Mid-German Crystalline High based on this presumption. 1. The magnitude of SHmax and the minimum horizontal stress (Shmin) in the region is close by, allowing local stress rotation. 2. The stiffness contrast perpendicular to the strike of the Variscan basement structures is large enough as stress source to cause significant rotation of the stress pattern.

Diamond Eye: a distributed architecture for image data mining

NASA Astrophysics Data System (ADS)

Burl, Michael C.; Fowlkes, Charless; Roden, Joe; Stechert, Andre; Mukhtar, Saleem

1999-02-01

Diamond Eye is a distributed software architecture, which enables users (scientists) to analyze large image collections by interacting with one or more custom data mining servers via a Java applet interface. Each server is coupled with an object-oriented database and a computational engine, such as a network of high-performance workstations. The database provides persistent storage and supports querying of the 'mined' information. The computational engine provides parallel execution of expensive image processing, object recognition, and query-by-content operations. Key benefits of the Diamond Eye architecture are: (1) the design promotes trial evaluation of advanced data mining and machine learning techniques by potential new users (all that is required is to point a web browser to the appropriate URL), (2) software infrastructure that is common across a range of science mining applications is factored out and reused, and (3) the system facilitates closer collaborations between algorithm developers and domain experts.

Translating PI observing proposals into ALMA observing scripts

NASA Astrophysics Data System (ADS)

Liszt, Harvey S.

2014-08-01

The ALMA telescope is a complex 66-antenna array working in the specialized domain of mm- and sub-mm aperture synthesis imaging. To make ALMA accessible to technically inexperienced but scientifically expert users, the ALMA Observing Tool (OT) has been developed. Using the OT, scientifically oriented user input is formatted as observing proposals that are packaged for peer-review and assessment of technical feasibility. If accepted, the proposal's scientifically oriented inputs are translated by the OT into scheduling blocks, which function as input to observing scripts for the telescope's online control system. Here I describe the processes and practices by which this translation from PI scientific goals to online control input and schedule block execution actually occurs.

The Design and Evaluation of "CAPTools"--A Computer Aided Parallelization Toolkit

NASA Technical Reports Server (NTRS)

Yan, Jerry; Frumkin, Michael; Hribar, Michelle; Jin, Haoqiang; Waheed, Abdul; Johnson, Steve; Cross, Jark; Evans, Emyr; Ierotheou, Constantinos; Leggett, Pete;

COBRApy: COnstraints-Based Reconstruction and Analysis for Python.

PubMed

Ebrahim, Ali; Lerman, Joshua A; Palsson, Bernhard O; Hyduke, Daniel R

2013-08-08

COnstraint-Based Reconstruction and Analysis (COBRA) methods are widely used for genome-scale modeling of metabolic networks in both prokaryotes and eukaryotes. Due to the successes with metabolism, there is an increasing effort to apply COBRA methods to reconstruct and analyze integrated models of cellular processes. The COBRA Toolbox for MATLAB is a leading software package for genome-scale analysis of metabolism; however, it was not designed to elegantly capture the complexity inherent in integrated biological networks and lacks an integration framework for the multiomics data used in systems biology. The openCOBRA Project is a community effort to promote constraints-based research through the distribution of freely available software. Here, we describe COBRA for Python (COBRApy), a Python package that provides support for basic COBRA methods. COBRApy is designed in an object-oriented fashion that facilitates the representation of the complex biological processes of metabolism and gene expression. COBRApy does not require MATLAB to function; however, it includes an interface to the COBRA Toolbox for MATLAB to facilitate use of legacy codes. For improved performance, COBRApy includes parallel processing support for computationally intensive processes. COBRApy is an object-oriented framework designed to meet the computational challenges associated with the next generation of stoichiometric constraint-based models and high-density omics data sets. http://opencobra.sourceforge.net/

Novel hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization estimation method for population pharmacokinetic data analysis.

PubMed

Ng, C M

2013-10-01

The development of a population PK/PD model, an essential component for model-based drug development, is both time- and labor-intensive. A graphical-processing unit (GPU) computing technology has been proposed and used to accelerate many scientific computations. The objective of this study was to develop a hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization (MCPEM) estimation algorithm for population PK data analysis. A hybrid GPU-CPU implementation of the MCPEM algorithm (MCPEMGPU) and identical algorithm that is designed for the single CPU (MCPEMCPU) were developed using MATLAB in a single computer equipped with dual Xeon 6-Core E5690 CPU and a NVIDIA Tesla C2070 GPU parallel computing card that contained 448 stream processors. Two different PK models with rich/sparse sampling design schemes were used to simulate population data in assessing the performance of MCPEMCPU and MCPEMGPU. Results were analyzed by comparing the parameter estimation and model computation times. Speedup factor was used to assess the relative benefit of parallelized MCPEMGPU over MCPEMCPU in shortening model computation time. The MCPEMGPU consistently achieved shorter computation time than the MCPEMCPU and can offer more than 48-fold speedup using a single GPU card. The novel hybrid GPU-CPU implementation of parallelized MCPEM algorithm developed in this study holds a great promise in serving as the core for the next-generation of modeling software for population PK/PD analysis.

Fibre Optic Connections And Method For Using Same

DOEpatents

Chan, Benson; Cohen, Mitchell S.; Fortier, Paul F.; Freitag, Ladd W.; Hall, Richard R.; Johnson, Glen W.; Lin, How Tzu; Sherman, John H.

2004-03-30

A package is described that couples a twelve channel wide fiber optic cable to a twelve channel Vertical Cavity Surface Emitting Laser (VCSEL) transmitter and a multiple channel Perpendicularly Aligned Integrated Die (PAID) receiver. The package allows for reduction in the height of the assembly package by vertically orienting certain dies parallel to the fiber optic cable and horizontally orienting certain other dies. The assembly allows the vertically oriented optoelectronic dies to be perpendicularly attached to the horizontally oriented laminate via a flexible circuit.

76 FR 63314 - Center for Scientific Review Notice of Closed Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-12

..., (Telephone Conference Call). Contact Person: Suzan Nadi, PhD, Scientific Review Officer, Center for... Mandarin Oriental, 1330 Maryland Avenue, SW., Washington, DC 20024. Contact Person: Mark Lindner, PhD.... Contact Person: Lilia Topol, PhD, Scientific Review Officer, Center for Scientific Review, National...

The nature of an object-oriented program: How do practitioners understand the nature of what they are creating?

NASA Astrophysics Data System (ADS)

Thompson, Errol; Kinshuk

2011-09-01

Object-oriented programming is seen as a difficult skill to master. There is considerable debate about the most appropriate way to introduce novice programmers to object-oriented concepts. Is it possible to uncover what the critical aspects or features are that enhance the learning of object-oriented programming? Practitioners have differing understandings of the nature of an object-oriented program. Uncovering these different ways of understanding leads to agreater understanding of the critical aspects and their relationship tothe structure of the program produced. A phenomenographic studywas conducted to uncover practitioner understandings of the nature of an object-oriented program. The study identified five levels of understanding and three dimensions of variation within these levels. These levels and dimensions of variation provide a framework for fostering conceptual change with respect to the nature of an object-oriented program.

The deflection of carbon composite carbon nanotube / graphene using molecular dynamics simulation

NASA Astrophysics Data System (ADS)

Kolesnikova, A. S.; Kirillova, I. V.; Kossovich, L. U.

2018-02-01

For the first time, the dependence of the bending force on the transverse displacement of atoms in the center of the composite material consisting of graphene and parallel oriented zigzag nanotubes was studied. Mathematical modeling of the action of the needle of the atomic force microscope was carried out using the single-layer armchair carbon nanotube. Armchair nanotubes are convenient for using them as a needle of an atomic force microscope, because their edges are not sharpened (unlike zigzag tubes). Consequently, armchair nanotubes will cause minimal damage upon contact with the investigation object. The geometric parameters of the composite was revealed under the action of the bending force of 6μN.

Research on rapid agile metrology for manufacturing based on real-time multitask operating system

NASA Astrophysics Data System (ADS)

Chen, Jihong; Song, Zhen; Yang, Daoshan; Zhou, Ji; Buckley, Shawn

1996-10-01

Rapid agile metrology for manufacturing (RAMM) using multiple non-contact sensors is likely to remain a growing trend in manufacturing. High speed inspecting systems for manufacturing is characterized by multitasks implemented in parallel and real-time events which occur simultaneously. In this paper, we introduce a real-time operating system into RAMM research. A general task model of a class-based object- oriented technology is proposed. A general multitask frame of a typical RAMM system using OPNet is discussed. Finally, an application example of a machine which inspects parts held on a carrier strip is described. With RTOS and OPNet, this machine can measure two dimensions of the contacts at 300 parts/second.

Object-Oriented Programming in High Schools the Turing Way.

ERIC Educational Resources Information Center

Holt, Richard C.

This paper proposes an approach to introducing object-oriented concepts to high school computer science students using the Object-Oriented Turing (OOT) language. Students can learn about basic object-oriented (OO) principles such as classes and inheritance by using and expanding a collection of classes that draw pictures like circles and happy…

Imaging, object detection, and change detection with a polarized multistatic GPR array

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beer, N. Reginald; Paglieroni, David W.

A polarized detection system performs imaging, object detection, and change detection factoring in the orientation of an object relative to the orientation of transceivers. The polarized detection system may operate on one of several modes of operation based on whether the imaging, object detection, or change detection is performed separately for each transceiver orientation. In combined change mode, the polarized detection system performs imaging, object detection, and change detection separately for each transceiver orientation, and then combines changes across polarizations. In combined object mode, the polarized detection system performs imaging and object detection separately for each transceiver orientation, and thenmore » combines objects across polarizations and performs change detection on the result. In combined image mode, the polarized detection system performs imaging separately for each transceiver orientation, and then combines images across polarizations and performs object detection followed by change detection on the result.« less

Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum

NASA Astrophysics Data System (ADS)

Fujiwara, Yoshihisa; Tomishige, Masahiko; Itoh, Yasuhiro; Fujiwara, Masao; Shibata, Naho; Kosaka, Toshikazu; Hosoya, Hiroshi; Tanimoto, Yoshifumi

2006-05-01

Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum was studied by using a superconducting magnet. Around a centre of a round vessel, random swimming at 0 T and aligned swimming parallel to the magnetic field (MF) of 8 T were observed. Near a wall of the vessel, however, swimming round and round along the wall at 0 T and aligned swimming of turning at right angles upon collision with the wall, which was remarkable around 1-4 T, were detected. It was experimentally revealed that the former MF-induced parallel swimming at the vessel centre was caused physicochemically by the parallel magnetic orientation of the cell itself. From magnetic field dependence of the extent of the orientation, the magnetic susceptibility anisotropy (χ ∥-χ ⊥) was first obtained to be 3.4× 10-23 emu cell-1 at 298 K for Paramecium caudatum. The orientation of the cell was considered to result from the magnetic orientation of the cell membrane. On the other hand, although mechanisms of the latter swimming near the vessel wall regardless of the absence and presence of the magnetic field are unclear at present, these experimental results indicate that whether the cell exists near the wall alters the magnetic field effect on the swimming in the horizontal magnetic field.

Web based aphasia test using service oriented architecture (SOA)

NASA Astrophysics Data System (ADS)

Voos, J. A.; Vigliecca, N. S.; Gonzalez, E. A.

2007-11-01

Based on an aphasia test for Spanish speakers which analyze the patient's basic resources of verbal communication, a web-enabled software was developed to automate its execution. A clinical database was designed as a complement, in order to evaluate the antecedents (risk factors, pharmacological and medical backgrounds, neurological or psychiatric symptoms, brain injury -anatomical and physiological characteristics, etc) which are necessary to carry out a multi-factor statistical analysis in different samples of patients. The automated test was developed following service oriented architecture and implemented in a web site which contains a tests suite, which would allow both integrating the aphasia test with other neuropsychological instruments and increasing the available site information for scientific research. The test design, the database and the study of its psychometric properties (validity, reliability and objectivity) were made in conjunction with neuropsychological researchers, who participate actively in the software design, based on the patients or other subjects of investigation feedback.

Challenges in Evaluating Clinical Governance Systems in Iran: A Qualitative Study

PubMed Central

Hooshmand, Elaheh; Tourani, Sogand; Ravaghi, Hamid; Ebrahimipour, Hossein

2014-01-01

Background: In spite of the pivotal role of clinical governance in enhancing quality of services provided by hospitals across the country, a scientific framework with specific criteria for evaluating hospitals has not been developed so far. Objectives: This study was conducted with the aim to identify the challenges involved in evaluating systems of clinical governance in Iran. Materials and Methods: For the purposes of this qualitative study, 15 semi-structured interviews with experts in the field were conducted in 2011 and the data were analyzed using framework analysis method. Results: Five major challenges in evaluating clinical governance include managing human resources, improving clinical quality, managing development, organizing clinical governance, and providing patient-oriented healthcare system. Conclusions: Healthcare system in Iran requires a clinical governance program which has a patient-oriented approach in philosophy, operation, and effectiveness in order to meet the challenges ahead. PMID:24910799

Test and Validation of the Mars Science Laboratory Robotic Arm

NASA Technical Reports Server (NTRS)

Robinson, M.; Collins, C.; Leger, P.; Kim, W.; Carsten, J.; Tompkins, V.; Trebi-Ollennu, A.; Florow, B.

2013-01-01

The Mars Science Laboratory Robotic Arm (RA) is a key component for achieving the primary scientific goals of the mission. The RA supports sample acquisition by precisely positioning a scoop above loose regolith or accurately preloading a percussive drill on Martian rocks or rover-mounted organic check materials. It assists sample processing by orienting a sample processing unit called CHIMRA through a series of gravity-relative orientations and sample delivery by positioning the sample portion door above an instrument inlet or the observation tray. In addition the RA facilitates contact science by accurately positioning the dust removal tool, Alpha Particle X-Ray Spectrometer (APXS) and the Mars Hand Lens Imager (MAHLI) relative to surface targets. In order to fulfill these seemingly disparate science objectives the RA must satisfy a variety of accuracy and performance requirements. This paper describes the necessary arm requirement specification and the test campaign to demonstrate these requirements were satisfied.

Sustaining Optimal Motivation: A Longitudinal Analysis of Interventions to Broaden Participation of Underrepresented Students in STEM

PubMed Central

Hernandez, Paul R.; Schultz, P. Wesley; Estrada, Mica; Woodcock, Anna; Chance, Randie C.

2013-01-01

The underrepresentation of racial minorities and women in science, technology, engineering, and mathematics (STEM) disciplines is a national concern. Goal theory provides a useful framework from which to understand issues of underrepresentation. We followed a large sample of high-achieving African American and Latino undergraduates in STEM disciplines attending 38 institutions of higher education in the United States over 3 academic years. We report on the science-related environmental factors and person factors that influence the longitudinal regulation of goal orientations. Further, we examine how goal orientations in turn influence distal academic outcomes such as performance and persistence in STEM. Using SEM-based parallel process latent growth curve modeling, we found that (a) engagement in undergraduate research was the only factor that buffered underrepresented students against an increase in performance-avoidance goals over time; (b) growth in scientific self-identity exhibited a strong positive effect on growth in task and performance-approach goals over time; (c) only task goals positively influenced students' cumulative grade point average, over and above baseline grade point average; and (d) performance-avoidance goals predicted student attrition from the STEM pipeline. We discuss the implications of these findings for underrepresented students in STEM disciplines. PMID:24273342

Parallel Volunteer Learning during Youth Programs

ERIC Educational Resources Information Center

Lesmeister, Marilyn K.; Green, Jeremy; Derby, Amy; Bothum, Candi

2012-01-01

Lack of time is a hindrance for volunteers to participate in educational opportunities, yet volunteer success in an organization is tied to the orientation and education they receive. Meeting diverse educational needs of volunteers can be a challenge for program managers. Scheduling a Volunteer Learning Track for chaperones that is parallel to a…

DNA looping by FokI: the impact of synapse geometry on loop topology at varied site orientations

PubMed Central

Rusling, David A.; Laurens, Niels; Pernstich, Christian; Wuite, Gijs J. L.; Halford, Stephen E.

2012-01-01

Most restriction endonucleases, including FokI, interact with two copies of their recognition sequence before cutting DNA. On DNA with two sites they act in cis looping out the intervening DNA. While many restriction enzymes operate symmetrically at palindromic sites, FokI acts asymmetrically at a non-palindromic site. The directionality of its sequence means that two FokI sites can be bridged in either parallel or anti-parallel alignments. Here we show by biochemical and single-molecule biophysical methods that FokI aligns two recognition sites on separate DNA molecules in parallel and that the parallel arrangement holds for sites in the same DNA regardless of whether they are in inverted or repeated orientations. The parallel arrangement dictates the topology of the loop trapped between sites in cis: the loop from inverted sites has a simple 180° bend, while that with repeated sites has a convoluted 360° turn. The ability of FokI to act at asymmetric sites thus enabled us to identify the synapse geometry for sites in trans and in cis, which in turn revealed the relationship between synapse geometry and loop topology. PMID:22362745

An open source workflow for 3D printouts of scientific data volumes

NASA Astrophysics Data System (ADS)

Loewe, P.; Klump, J. F.; Wickert, J.; Ludwig, M.; Frigeri, A.

2013-12-01

As the amount of scientific data continues to grow, researchers need new tools to help them visualize complex data. Immersive data-visualisations are helpful, yet fail to provide tactile feedback and sensory feedback on spatial orientation, as provided from tangible objects. The gap in sensory feedback from virtual objects leads to the development of tangible representations of geospatial information to solve real world problems. Examples are animated globes [1], interactive environments like tangible GIS [2], and on demand 3D prints. The production of a tangible representation of a scientific data set is one step in a line of scientific thinking, leading from the physical world into scientific reasoning and back: The process starts with a physical observation, or from a data stream generated by an environmental sensor. This data stream is turned into a geo-referenced data set. This data is turned into a volume representation which is converted into command sequences for the printing device, leading to the creation of a 3D printout. As a last, but crucial step, this new object has to be documented and linked to the associated metadata, and curated in long term repositories to preserve its scientific meaning and context. The workflow to produce tangible 3D data-prints from science data at the German Research Centre for Geosciences (GFZ) was implemented as a software based on the Free and Open Source Geoinformatics tools GRASS GIS and Paraview. The workflow was successfully validated in various application scenarios at GFZ using a RapMan printer to create 3D specimens of elevation models, geological underground models, ice penetrating radar soundings for planetology, and space time stacks for Tsunami model quality assessment. While these first pilot applications have demonstrated the feasibility of the overall approach [3], current research focuses on the provision of the workflow as Software as a Service (SAAS), thematic generalisation of information content and long term curation. [1] http://www.arcscience.com/systemDetails/omniTechnology.html [2] http://video.esri.com/watch/53/landscape-design-with-tangible-gis [3] Löwe et al. (2013), Geophysical Research Abstracts, Vol. 15, EGU2013-1544-1.

Choice of Grating Orientation for Evaluation of Peripheral Vision

PubMed Central

Venkataraman, Abinaya Priya; Winter, Simon; Rosén, Robert; Lundström, Linda

2016-01-01

ABSTRACT Purpose Peripheral resolution acuity depends on the orientation of the stimuli. However, it is uncertain if such a meridional effect also exists for peripheral detection tasks because they are affected by optical errors. Knowledge of the quantitative differences in acuity for different grating orientations is crucial for choosing the appropriate stimuli for evaluations of peripheral resolution and detection tasks. We assessed resolution and detection thresholds for different grating orientations in the peripheral visual field. Methods Resolution and detection thresholds were evaluated for gratings of four different orientations in eight different visual field meridians in the 20-deg visual field in white light. Detection measurements in monochromatic light (543 nm; bandwidth, 10 nm) were also performed to evaluate the effects of chromatic aberration on the meridional effect. A combination of trial lenses and adaptive optics system was used to correct the monochromatic lower- and higher-order aberrations. Results For both resolution and detection tasks, gratings parallel to the visual field meridian had better threshold compared with the perpendicular gratings, whereas the two oblique gratings had similar thresholds. The parallel and perpendicular grating acuity differences for resolution and detection tasks were 0.16 logMAR and 0.11 logMAD, respectively. Elimination of chromatic errors did not affect the meridional preference in detection acuity. Conclusions Similar to peripheral resolution, detection also shows a meridional effect that appears to have a neural origin. The threshold difference seen for parallel and perpendicular gratings suggests the use of two oblique gratings as stimuli in alternative forced-choice procedures for peripheral vision evaluation to reduce measurement variation. PMID:26889822

Choice of Grating Orientation for Evaluation of Peripheral Vision.

PubMed

Venkataraman, Abinaya Priya; Winter, Simon; Rosén, Robert; Lundström, Linda

2016-06-01

Peripheral resolution acuity depends on the orientation of the stimuli. However, it is uncertain if such a meridional effect also exists for peripheral detection tasks because they are affected by optical errors. Knowledge of the quantitative differences in acuity for different grating orientations is crucial for choosing the appropriate stimuli for evaluations of peripheral resolution and detection tasks. We assessed resolution and detection thresholds for different grating orientations in the peripheral visual field. Resolution and detection thresholds were evaluated for gratings of four different orientations in eight different visual field meridians in the 20-deg visual field in white light. Detection measurements in monochromatic light (543 nm; bandwidth, 10 nm) were also performed to evaluate the effects of chromatic aberration on the meridional effect. A combination of trial lenses and adaptive optics system was used to correct the monochromatic lower- and higher-order aberrations. For both resolution and detection tasks, gratings parallel to the visual field meridian had better threshold compared with the perpendicular gratings, whereas the two oblique gratings had similar thresholds. The parallel and perpendicular grating acuity differences for resolution and detection tasks were 0.16 logMAR and 0.11 logMAD, respectively. Elimination of chromatic errors did not affect the meridional preference in detection acuity. Similar to peripheral resolution, detection also shows a meridional effect that appears to have a neural origin. The threshold difference seen for parallel and perpendicular gratings suggests the use of two oblique gratings as stimuli in alternative forced-choice procedures for peripheral vision evaluation to reduce measurement variation.

A DBMS architecture for global change research

NASA Astrophysics Data System (ADS)

Hachem, Nabil I.; Gennert, Michael A.; Ward, Matthew O.

1993-08-01

The goal of this research is the design and development of an integrated system for the management of very large scientific databases, cartographic/geographic information processing, and exploratory scientific data analysis for global change research. The system will represent both spatial and temporal knowledge about natural and man-made entities on the eath's surface, following an object-oriented paradigm. A user will be able to derive, modify, and apply, procedures to perform operations on the data, including comparison, derivation, prediction, validation, and visualization. This work represents an effort to extend the database technology with an intrinsic class of operators, which is extensible and responds to the growing needs of scientific research. Of significance is the integration of many diverse forms of data into the database, including cartography, geography, hydrography, hypsography, images, and urban planning data. Equally important is the maintenance of metadata, that is, data about the data, such as coordinate transformation parameters, map scales, and audit trails of previous processing operations. This project will impact the fields of geographical information systems and global change research as well as the database community. It will provide an integrated database management testbed for scientific research, and a testbed for the development of analysis tools to understand and predict global change.

System and method for representing and manipulating three-dimensional objects on massively parallel architectures

DOEpatents

Karasick, Michael S.; Strip, David R.

1996-01-01

A parallel computing system is described that comprises a plurality of uniquely labeled, parallel processors, each processor capable of modelling a three-dimensional object that includes a plurality of vertices, faces and edges. The system comprises a front-end processor for issuing a modelling command to the parallel processors, relating to a three-dimensional object. Each parallel processor, in response to the command and through the use of its own unique label, creates a directed-edge (d-edge) data structure that uniquely relates an edge of the three-dimensional object to one face of the object. Each d-edge data structure at least includes vertex descriptions of the edge and a description of the one face. As a result, each processor, in response to the modelling command, operates upon a small component of the model and generates results, in parallel with all other processors, without the need for processor-to-processor intercommunication.

CICT Computing, Information, and Communications Technology Program

NASA Technical Reports Server (NTRS)

Laufenberg, Lawrence; Tu, Eugene (Technical Monitor)

2002-01-01

The CICT Program is part of the NASA Aerospace Technology Enterprise's fundamental technology thrust to develop tools. processes, and technologies that enable new aerospace system capabilities and missions. The CICT Program's four key objectives are: Provide seamless access to NASA resources- including ground-, air-, and space-based distributed information technology resources-so that NASA scientists and engineers can more easily control missions, make new scientific discoveries, and design the next-generation space vehicles, provide high-data delivery from these assets directly to users for missions, develop goal-oriented human-centered systems, and research, develop and evaluate revolutionary technology.

Strategies for a permanent lunar base

NASA Technical Reports Server (NTRS)

Duke, M. B.; Mendell, W. W.; Roberts, B. B.

1985-01-01

One or more of three possible objectives, encompassing scientific research, lunar resource exploitation for space infrastructure construction, and lunar environment self-sufficiency refinement with a view to future planetary habitation, may be the purpose of manned lunar base activities. Attention is presently given to the possibility that the early phases of all three lunar base orientations may be developed in such a way as to share the greatest number of common elements. An evaluation is made of the cost and complexity of the lunar base, and the Space Transportation System used in conjunction with it, as functions of long term base use strategy.

Cross-language Babel structs—making scientific interfaces more efficient

NASA Astrophysics Data System (ADS)

Prantl, Adrian; Ebner, Dietmar; Epperly, Thomas G. W.

2013-01-01

Babel is an open-source language interoperability framework tailored to the needs of high-performance scientific computing. As an integral element of the Common Component Architecture, it is employed in a wide range of scientific applications where it is used to connect components written in different programming languages. In this paper we describe how we extended Babel to support interoperable tuple data types (structs). Structs are a common idiom in (mono-lingual) scientific application programming interfaces (APIs); they are an efficient way to pass tuples of nonuniform data between functions, and are supported natively by most programming languages. Using our extended version of Babel, developers of scientific codes can now pass structs as arguments between functions implemented in any of the supported languages. In C, C++, Fortran 2003/2008 and Chapel, structs can be passed without the overhead of data marshaling or copying, providing language interoperability at minimal cost. Other supported languages are Fortran 77, Fortran 90/95, Java and Python. We will show how we designed a struct implementation that is interoperable with all of the supported languages and present benchmark data to compare the performance of all language bindings, highlighting the differences between languages that offer native struct support and an object-oriented interface with getter/setter methods. A case study shows how structs can help simplify the interfaces of scientific codes significantly.

Scientific Understanding of Sexual Orientation: Implications for Science Education.

ERIC Educational Resources Information Center

Good, Ron; Hafner, Mark; Peebles, Patsye

2000-01-01

Discusses sexual orientation using the analogy of handedness. Points out the presence of diverse sexual behavior and homosexuality among living species and focuses on human behavior. Encourages discussions among biology teachers on the origins of sexual orientation. (Contains 27 references.) (YDS)

Does Early Childhood Teacher Education Affect Students' Cognitive Orientations? The Effect of Different Education Tracks in Teacher Education on Prospective Early Childhood Teachers' Cognitive Orientations in Germany

ERIC Educational Resources Information Center

Mischo, Christoph; Wahl, Stefan; Strohmer, Janina; Wolf, Carina

2014-01-01

Early childhood teachers may differ regarding the knowledge base they use when making professional decisions. In this study two orientations are distinguished: the orientation towards scientific knowledge vs. the orientation towards intuition and subjective experience. As different tracks in early childhood teacher education qualify for…

What Is Scientific Thinking?

ERIC Educational Resources Information Center

Tweney, Ryan D.

Drawing parallels with critical thinking and creative thinking, this document describes some ways that scientific thinking is utilized. Cognitive approaches to scientific thinking are discussed, and it is argued that all science involves an attempt to construct a testable mental model of some aspect of reality. The role of mental models is…

Dynamic file-access characteristics of a production parallel scientific workload

NASA Technical Reports Server (NTRS)

Kotz, David; Nieuwejaar, Nils

1994-01-01

Multiprocessors have permitted astounding increases in computational performance, but many cannot meet the intense I/O requirements of some scientific applications. An important component of any solution to this I/O bottleneck is a parallel file system that can provide high-bandwidth access to tremendous amounts of data in parallel to hundreds or thousands of processors. Most successful systems are based on a solid understanding of the expected workload, but thus far there have been no comprehensive workload characterizations of multiprocessor file systems. This paper presents the results of a three week tracing study in which all file-related activity on a massively parallel computer was recorded. Our instrumentation differs from previous efforts in that it collects information about every I/O request and about the mix of jobs running in a production environment. We also present the results of a trace-driven caching simulation and recommendations for designers of multiprocessor file systems.

Cortical neurons of bats respond best to echoes from nearest targets when listening to natural biosonar multi-echo streams.

PubMed

Beetz, M Jerome; Hechavarría, Julio C; Kössl, Manfred

2016-10-27

Bats orientate in darkness by listening to echoes from their biosonar calls, a behaviour known as echolocation. Recent studies showed that cortical neurons respond in a highly selective manner when stimulated with natural echolocation sequences that contain echoes from single targets. However, it remains unknown how cortical neurons process echolocation sequences containing echo information from multiple objects. In the present study, we used echolocation sequences containing echoes from three, two or one object separated in the space depth as stimuli to study neuronal activity in the bat auditory cortex. Neuronal activity was recorded with multi-electrode arrays placed in the dorsal auditory cortex, where neurons tuned to target-distance are found. Our results show that target-distance encoding neurons are mostly selective to echoes coming from the closest object, and that the representation of echo information from distant objects is selectively suppressed. This suppression extends over a large part of the dorsal auditory cortex and may override possible parallel processing of multiple objects. The presented data suggest that global cortical suppression might establish a cortical "default mode" that allows selectively focusing on close obstacle even without active attention from the animals.

Cortical neurons of bats respond best to echoes from nearest targets when listening to natural biosonar multi-echo streams

PubMed Central

Beetz, M. Jerome; Hechavarría, Julio C.; Kössl, Manfred

2016-01-01

Bats orientate in darkness by listening to echoes from their biosonar calls, a behaviour known as echolocation. Recent studies showed that cortical neurons respond in a highly selective manner when stimulated with natural echolocation sequences that contain echoes from single targets. However, it remains unknown how cortical neurons process echolocation sequences containing echo information from multiple objects. In the present study, we used echolocation sequences containing echoes from three, two or one object separated in the space depth as stimuli to study neuronal activity in the bat auditory cortex. Neuronal activity was recorded with multi-electrode arrays placed in the dorsal auditory cortex, where neurons tuned to target-distance are found. Our results show that target-distance encoding neurons are mostly selective to echoes coming from the closest object, and that the representation of echo information from distant objects is selectively suppressed. This suppression extends over a large part of the dorsal auditory cortex and may override possible parallel processing of multiple objects. The presented data suggest that global cortical suppression might establish a cortical “default mode” that allows selectively focusing on close obstacle even without active attention from the animals. PMID:27786252

Methods for design and evaluation of parallel computating systems (The PISCES project)

NASA Technical Reports Server (NTRS)

Pratt, Terrence W.; Wise, Robert; Haught, Mary JO

1989-01-01

The PISCES project started in 1984 under the sponsorship of the NASA Computational Structural Mechanics (CSM) program. A PISCES 1 programming environment and parallel FORTRAN were implemented in 1984 for the DEC VAX (using UNIX processes to simulate parallel processes). This system was used for experimentation with parallel programs for scientific applications and AI (dynamic scene analysis) applications. PISCES 1 was ported to a network of Apollo workstations by N. Fitzgerald.

Towards a general object-oriented software development methodology

NASA Technical Reports Server (NTRS)

Seidewitz, ED; Stark, Mike

1986-01-01

An object is an abstract software model of a problem domain entity. Objects are packages of both data and operations of that data (Goldberg 83, Booch 83). The Ada (tm) package construct is representative of this general notion of an object. Object-oriented design is the technique of using objects as the basic unit of modularity in systems design. The Software Engineering Laboratory at the Goddard Space Flight Center is currently involved in a pilot program to develop a flight dynamics simulator in Ada (approximately 40,000 statements) using object-oriented methods. Several authors have applied object-oriented concepts to Ada (e.g., Booch 83, Cherry 85). It was found that these methodologies are limited. As a result a more general approach was synthesized with allows a designer to apply powerful object-oriented principles to a wide range of applications and at all stages of design. An overview is provided of this approach. Further, how object-oriented design fits into the overall software life-cycle is considered.

Parallel Processing Systems for Passive Ranging During Helicopter Flight

NASA Technical Reports Server (NTRS)

Sridhar, Bavavar; Suorsa, Raymond E.; Showman, Robert D. (Technical Monitor)

1994-01-01

The complexity of rotorcraft missions involving operations close to the ground result in high pilot workload. In order to allow a pilot time to perform mission-oriented tasks, sensor-aiding and automation of some of the guidance and control functions are highly desirable. Images from an electro-optical sensor provide a covert way of detecting objects in the flight path of a low-flying helicopter. Passive ranging consists of processing a sequence of images using techniques based on optical low computation and recursive estimation. The passive ranging algorithm has to extract obstacle information from imagery at rates varying from five to thirty or more frames per second depending on the helicopter speed. We have implemented and tested the passive ranging algorithm off-line using helicopter-collected images. However, the real-time data and computation requirements of the algorithm are beyond the capability of any off-the-shelf microprocessor or digital signal processor. This paper describes the computational requirements of the algorithm and uses parallel processing technology to meet these requirements. Various issues in the selection of a parallel processing architecture are discussed and four different computer architectures are evaluated regarding their suitability to process the algorithm in real-time. Based on this evaluation, we conclude that real-time passive ranging is a realistic goal and can be achieved with a short time.

The bandwidth of consolidation into visual short-term memory (VSTM) depends on the visual feature

PubMed Central

Miller, James R.; Becker, Mark W.; Liu, Taosheng

2014-01-01

We investigated the nature of the bandwidth limit in the consolidation of visual information into visual short-term memory. In the first two experiments, we examined whether previous results showing differential consolidation bandwidth for color and orientation resulted from methodological differences by testing the consolidation of color information with methods used in prior orientation experiments. We briefly presented two color patches with masks, either sequentially or simultaneously, followed by a location cue indicating the target. Participants identified the target color via button-press (Experiment 1) or by clicking a location on a color wheel (Experiment 2). Although these methods have previously demonstrated that two orientations are consolidated in a strictly serial fashion, here we found equivalent performance in the sequential and simultaneous conditions, suggesting that two colors can be consolidated in parallel. To investigate whether this difference resulted from different consolidation mechanisms or a common mechanism with different features consuming different amounts of bandwidth, Experiment 3 presented a color patch and an oriented grating either sequentially or simultaneously. We found a lower performance in the simultaneous than the sequential condition, with orientation showing a larger impairment than color. These results suggest that consolidation of both features share common mechanisms. However, it seems that color requires less information to be encoded than orientation. As a result two colors can be consolidated in parallel without exceeding the bandwidth limit, whereas two orientations or an orientation and a color exceed the bandwidth and appear to be consolidated serially. PMID:25317065

Effect of crystal orientation on conductivity and electron mobility in single-crystal alumina

NASA Technical Reports Server (NTRS)

Will, Fritz G.; Delorenzi, Horst G.; Janora, Kevin H.

1992-01-01

The electrical conductivity of high-purity, single-crystal alumina is determined parallel to and perpendicular to the c-axis. The mean conductivity of four samples of each orientation is a factor 3.3 higher parallel to the c-axis than perpendicular to it. The conductivity as a function of temperature is attributed to extrinsic electron conduction at temperatures from 400 to 900 C, and intrinsic semiconduction at temperatures from 900 to 1300 C. In the high-temperature regime, the slope on all eight specimens is 4.7 +/- 0.1 eV. Hence, the thermal bandgap at O K is 9.4 +/- 0.2 eV.

Subnanosecond-laser-induced periodic surface structures on prescratched silicon substrate

NASA Astrophysics Data System (ADS)

Hongo, Motoharu; Matsuo, Shigeki

2016-06-01

Laser-induced periodic surface structures (LIPSS) were fabricated on a prescratched silicon surface by irradiation with subnanosecond laser pulses. Low-spatial-frequency LIPSS (LSFL) were observed in the central and peripheral regions; both had a period Λ close to the laser wavelength λ, and the wavevector orientation was parallel to the electric field of the laser beam. The LSFL in the peripheral region seemed to be growing, that is, expanding in length with increasing number of pulses, into the outer regions. In addition, high-spatial-frequency LIPSS, Λ ≲ λ /2, were found along the scratches, and their wavevector orientation was parallel to the scratches.

Orientation-Enhanced Parallel Coordinate Plots.

PubMed

Raidou, Renata Georgia; Eisemann, Martin; Breeuwer, Marcel; Eisemann, Elmar; Vilanova, Anna

2016-01-01

Parallel Coordinate Plots (PCPs) is one of the most powerful techniques for the visualization of multivariate data. However, for large datasets, the representation suffers from clutter due to overplotting. In this case, discerning the underlying data information and selecting specific interesting patterns can become difficult. We propose a new and simple technique to improve the display of PCPs by emphasizing the underlying data structure. Our Orientation-enhanced Parallel Coordinate Plots (OPCPs) improve pattern and outlier discernibility by visually enhancing parts of each PCP polyline with respect to its slope. This enhancement also allows us to introduce a novel and efficient selection method, the Orientation-enhanced Brushing (O-Brushing). Our solution is particularly useful when multiple patterns are present or when the view on certain patterns is obstructed by noise. We present the results of our approach with several synthetic and real-world datasets. Finally, we conducted a user evaluation, which verifies the advantages of the OPCPs in terms of discernibility of information in complex data. It also confirms that O-Brushing eases the selection of data patterns in PCPs and reduces the amount of necessary user interactions compared to state-of-the-art brushing techniques.

The influence of grasping habits and object orientation on motor planning in children and adults.

PubMed

Jovanovic, Bianca; Schwarzer, Gudrun

2017-12-01

We investigated the influence of habitual grasp strategies and object orientation on motor planning in 3-year-olds and 4- to 5-year-old children and adults. Participants were required to rotate different vertically oriented objects around 180°. Usually, adults perform this task by grasping objects with an awkward grip (thumb and index finger pointing downward) at the beginning of the movement, in order to finish it with a comfortable hand position. This pattern corresponds to the well-known end-state comfort effect (ESC) in grasp planning. The presented objects were associated with different habitual grasp orientations that either corresponded with the grasp direction required to reach end-state comfort (downward) or implied a contrary grasp orientation (upward). Additionally, they were presented either in their usual, canonical orientation (e.g., shovel with the blade oriented downward versus cup with its opening oriented upward) or upside down. As dependent variable we analyzed the number of grips conforming to the end-state comfort principle (ESC score) realized in each object type and orientation condition. The number of grips conforming to ESC strongly increased with age. In addition, the extent to which end-state comfort was considered was influenced by the actual orientation of the objects' functional parts. Thus, in all age-groups the ESC score was highest when the functional parts of the objects were oriented downward (shovel presented canonically with blade pointing downward, cup presented upside down) and corresponded to the hand orientation needed to realize ESC. © 2017 Wiley Periodicals, Inc.

Acoustic positioning and orientation prediction

NASA Technical Reports Server (NTRS)

Barmatz, Martin B. (Inventor); Aveni, Glenn (Inventor); Putterman, Seth (Inventor); Rudnick, Joseph (Inventor)

1990-01-01

A method is described for use with an acoustic positioner, which enables a determination of the equilibrium position and orientation which an object assumes in a zero gravity environment, as well as restoring forces and torques of an object in an acoustic standing wave field. An acoustic standing wave field is established in the chamber, and the object is held at several different positions near the expected equilibrium position. While the object is held at each position, the center resonant frequency of the chamber is determined, by noting which frequency results in the greatest pressure of the acoustic field. The object position which results in the lowest center resonant frequency is the equilibrium position. The orientation of a nonspherical object is similarly determined, by holding the object in a plurality of different orientations at its equilibrium position, and noting the center resonant frequency for each orientation. The orientation which results in the lowest center resonant frequency is the equilibrium orientation. Where the acoustic frequency is constant, but the chamber length is variable, the equilibrium position or orientation is that which results in the greatest chamber length at the center resonant frequency.

The effect of implied orientation derived from verbal context on picture recognition.

PubMed

Stanfield, R A; Zwaan, R A

2001-03-01

Perceptual symbol systems assume an analogue relationship between a symbol and its referent, whereas amodal symbol systems assume an arbitrary relationship between a symbol and its referent. According to perceptual symbol theories, the complete representation of an object, called a simulation, should reflect physical characteristics of the object. Amodal theories, in contrast, do not make this prediction. We tested the hypothesis, derived from perceptual symbol theories, that people mentally represent the orientation of an object implied by a verbal description. Orientation (vertical-horizontal) was manipulated by having participants read a sentence that implicitly suggested a particular orientation for an object. Then recognition latencies to pictures of the object in each of the two orientations were measured. Pictures matching the orientation of the object implied by the sentence were responded to faster than pictures that did not match the orientation. This finding is interpreted as offering support for theories positing perceptual symbol systems.

On the utility of threads for data parallel programming

NASA Technical Reports Server (NTRS)

Fahringer, Thomas; Haines, Matthew; Mehrotra, Piyush

1995-01-01

Threads provide a useful programming model for asynchronous behavior because of their ability to encapsulate units of work that can then be scheduled for execution at runtime, based on the dynamic state of a system. Recently, the threaded model has been applied to the domain of data parallel scientific codes, and initial reports indicate that the threaded model can produce performance gains over non-threaded approaches, primarily through the use of overlapping useful computation with communication latency. However, overlapping computation with communication is possible without the benefit of threads if the communication system supports asynchronous primitives, and this comparison has not been made in previous papers. This paper provides a critical look at the utility of lightweight threads as applied to data parallel scientific programming.

Dark-field transmission electron microscopy of cortical bone reveals details of extrafibrillar crystals.

PubMed

Schwarcz, Henry P; McNally, Elizabeth A; Botton, Gianluigi A

2014-12-01

In a previous study we showed that most of the mineral in bone is present in the form of "mineral structures", 5-6nm-thick, elongated plates which surround and are oriented parallel to collagen fibrils. Using dark-field transmission electron microscopy, we viewed mineral structures in ion-milled sections of cortical human bone cut parallel to the collagen fibrils. Within the mineral structures we observe single crystals of apatite averaging 5.8±2.7nm in width and 28±19nm in length, their long axes oriented parallel to the fibril axis. Some appear to be composite, co-aligned crystals as thin as 2nm. From their similarity to TEM images of crystals liberated from deproteinated bone we infer that we are viewing sections through platy crystals of apatite that are assembled together to form the mineral structures. Copyright © 2014 Elsevier Inc. All rights reserved.

A Study on the Difficulties of Learning Phase Transition in Object-Oriented Analysis and Design from the Viewpoint of Semantic Distance

ERIC Educational Resources Information Center

Shin, Shin-Shing

2015-01-01

Students in object-oriented analysis and design (OOAD) courses typically encounter difficulties transitioning from object-oriented analysis (OOA) to logical design (OOLD). This study conducted an empirical experiment to examine these learning difficulties by evaluating differences between OOA-to-OOLD and OOLD-to-object-oriented-physical-design…

The Nature of an Object-Oriented Program: How Do Practitioners Understand the Nature of What They Are Creating?

ERIC Educational Resources Information Center

Thompson, Errol; Kinshuk

2011-01-01

Object-oriented programming is seen as a difficult skill to master. There is considerable debate about the most appropriate way to introduce novice programmers to object-oriented concepts. Is it possible to uncover what the critical aspects or features are that enhance the learning of object-oriented programming? Practitioners have differing…

Quo vadis, analytical chemistry?

PubMed

Valcárcel, Miguel

2016-01-01

This paper presents an open, personal, fresh approach to the future of Analytical Chemistry in the context of the deep changes Science and Technology are anticipated to experience. Its main aim is to challenge young analytical chemists because the future of our scientific discipline is in their hands. A description of not completely accurate overall conceptions of our discipline, both past and present, to be avoided is followed by a flexible, integral definition of Analytical Chemistry and its cornerstones (viz., aims and objectives, quality trade-offs, the third basic analytical reference, the information hierarchy, social responsibility, independent research, transfer of knowledge and technology, interfaces to other scientific-technical disciplines, and well-oriented education). Obsolete paradigms, and more accurate general and specific that can be expected to provide the framework for our discipline in the coming years are described. Finally, the three possible responses of analytical chemists to the proposed changes in our discipline are discussed.

Research for Change: the role of scientific journals publishing mental health research.

PubMed

Saxena, Shekhar; Sharan, Pratap; Saraceno, Benedetto

2004-06-01

There is an enormous gap between the burden of mental disorders and mental health resources in low- and middle-income countries. The Mental Health: Global Action Programme of the World Health Organization (WHO) envisions an active role for research in the multidimensional efforts required to change the current mental health situation in these countries (Research for Change). WHO's strategies to achieve this include developing a research policy and a priority agenda at country level with active collaboration from all stakeholders, building research capacity and infrastructure and involving scientific journals to stimulate and disseminate public health oriented research. A recently agreed joint statement by editors of prominent journals publishing mental health research and WHO sets major objectives and some possible strategies for achieving this. WHO is committed to making Research for Change a reality by working with partners who share this aim.

SafeConnect Solar - Final Scientific/Technical Report (Updated)

DOE Office of Scientific and Technical Information (OSTI.GOV)

McNish, Zachary

2016-02-03

Final Scientific/Technical Report from Tier 0 SunShot Incubator award for hardware-based solution to reducing soft costs of installed solar. The primary objective of this project was for SafeConnect Solar (“SafeConnect”) to create working proof-of-concept hardware prototypes from its proprietary intellectual property and business concepts for a plug-and-play, safety-oriented hardware solution for photovoltaic solar systems. Specifically, SafeConnect sought to build prototypes of its “SmartBox” and related cabling and connectors, as well as the firmware needed to run the hardware. This hardware is designed to ensure a residential PV system installed with it can address all safety concerns that currently form themore » basis of AHJ electrical permitting and licensing requirements, thereby reducing the amount of permitting and specialized labor required on a residential PV system, and also opening up new sales channels and customer acquisition opportunities.« less

Research for Change: the role of scientific journals publishing mental health research

PubMed Central

Saxena, Shekhar; Sharan, Pratap; Saraceno, Benedetto

2004-01-01

There is an enormous gap between the burden of mental disorders and mental health resources in low- and middle-income countries. The Mental Health: Global Action Programme of the World Health Organization (WHO) envisions an active role for research in the multidimensional efforts required to change the current mental health situation in these countries (Research for Change). WHO's strategies to achieve this include developing a research policy and a priority agenda at country level with active collaboration from all stakeholders, building research capacity and infrastructure and involving scientific journals to stimulate and disseminate public health oriented research. A recently agreed joint statement by editors of prominent journals publishing mental health research and WHO sets major objectives and some possible strategies for achieving this. WHO is committed to making Research for Change a reality by working with partners who share this aim. PMID:16633460

Experience Paper: Software Engineering and Community Codes Track in ATPESC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dubey, Anshu; Riley, Katherine M.

Argonne Training Program in Extreme Scale Computing (ATPESC) was started by the Argonne National Laboratory with the objective of expanding the ranks of better prepared users of high performance computing (HPC) machines. One of the unique aspects of the program was inclusion of software engineering and community codes track. The inclusion was motivated by the observation that the projects with a good scientific and software process were better able to meet their scientific goals. In this paper we present our experience of running the software track from the beginning of the program until now. We discuss the motivations, the reception,more » and the evolution of the track over the years. We welcome discussion and input from the community to enhance the track in ATPESC, and also to facilitate inclusion of similar tracks in other HPC oriented training programs.« less

chemf: A purely functional chemistry toolkit.

PubMed

Höck, Stefan; Riedl, Rainer

2012-12-20

Although programming in a type-safe and referentially transparent style offers several advantages over working with mutable data structures and side effects, this style of programming has not seen much use in chemistry-related software. Since functional programming languages were designed with referential transparency in mind, these languages offer a lot of support when writing immutable data structures and side-effects free code. We therefore started implementing our own toolkit based on the above programming paradigms in a modern, versatile programming language. We present our initial results with functional programming in chemistry by first describing an immutable data structure for molecular graphs together with a couple of simple algorithms to calculate basic molecular properties before writing a complete SMILES parser in accordance with the OpenSMILES specification. Along the way we show how to deal with input validation, error handling, bulk operations, and parallelization in a purely functional way. At the end we also analyze and improve our algorithms and data structures in terms of performance and compare it to existing toolkits both object-oriented and purely functional. All code was written in Scala, a modern multi-paradigm programming language with a strong support for functional programming and a highly sophisticated type system. We have successfully made the first important steps towards a purely functional chemistry toolkit. The data structures and algorithms presented in this article perform well while at the same time they can be safely used in parallelized applications, such as computer aided drug design experiments, without further adjustments. This stands in contrast to existing object-oriented toolkits where thread safety of data structures and algorithms is a deliberate design decision that can be hard to implement. Finally, the level of type-safety achieved by Scala highly increased the reliability of our code as well as the productivity of the programmers involved in this project.

chemf: A purely functional chemistry toolkit

PubMed Central

2012-01-01

Background Although programming in a type-safe and referentially transparent style offers several advantages over working with mutable data structures and side effects, this style of programming has not seen much use in chemistry-related software. Since functional programming languages were designed with referential transparency in mind, these languages offer a lot of support when writing immutable data structures and side-effects free code. We therefore started implementing our own toolkit based on the above programming paradigms in a modern, versatile programming language. Results We present our initial results with functional programming in chemistry by first describing an immutable data structure for molecular graphs together with a couple of simple algorithms to calculate basic molecular properties before writing a complete SMILES parser in accordance with the OpenSMILES specification. Along the way we show how to deal with input validation, error handling, bulk operations, and parallelization in a purely functional way. At the end we also analyze and improve our algorithms and data structures in terms of performance and compare it to existing toolkits both object-oriented and purely functional. All code was written in Scala, a modern multi-paradigm programming language with a strong support for functional programming and a highly sophisticated type system. Conclusions We have successfully made the first important steps towards a purely functional chemistry toolkit. The data structures and algorithms presented in this article perform well while at the same time they can be safely used in parallelized applications, such as computer aided drug design experiments, without further adjustments. This stands in contrast to existing object-oriented toolkits where thread safety of data structures and algorithms is a deliberate design decision that can be hard to implement. Finally, the level of type-safety achieved by Scala highly increased the reliability of our code as well as the productivity of the programmers involved in this project. PMID:23253942

Containment of groundwater contamination plumes: minimizing drawdown by aligning capture wells parallel to regional flow

NASA Astrophysics Data System (ADS)

Christ, John A.; Goltz, Mark N.

2004-01-01

Pump-and-treat systems that are installed to contain contaminated groundwater migration typically involve placement of extraction wells perpendicular to the regional groundwater flow direction at the down gradient edge of a contaminant plume. These wells capture contaminated water for above ground treatment and disposal, thereby preventing further migration of contaminated water down gradient. In this work, examining two-, three-, and four-well systems, we compare well configurations that are parallel and perpendicular to the regional groundwater flow direction. We show that orienting extraction wells co-linearly, parallel to regional flow, results in (1) a larger area of aquifer influenced by the wells at a given total well flow rate, (2) a center and ultimate capture zone width equal to the perpendicular configuration, and (3) more flexibility with regard to minimizing drawdown. Although not suited for some scenarios, we found orienting extraction wells parallel to regional flow along a plume centerline, when compared to a perpendicular configuration, reduces drawdown by up to 7% and minimizes the fraction of uncontaminated water captured.

Cloud parallel processing of tandem mass spectrometry based proteomics data.

PubMed

Mohammed, Yassene; Mostovenko, Ekaterina; Henneman, Alex A; Marissen, Rob J; Deelder, André M; Palmblad, Magnus

2012-10-05

Data analysis in mass spectrometry based proteomics struggles to keep pace with the advances in instrumentation and the increasing rate of data acquisition. Analyzing this data involves multiple steps requiring diverse software, using different algorithms and data formats. Speed and performance of the mass spectral search engines are continuously improving, although not necessarily as needed to face the challenges of acquired big data. Improving and parallelizing the search algorithms is one possibility; data decomposition presents another, simpler strategy for introducing parallelism. We describe a general method for parallelizing identification of tandem mass spectra using data decomposition that keeps the search engine intact and wraps the parallelization around it. We introduce two algorithms for decomposing mzXML files and recomposing resulting pepXML files. This makes the approach applicable to different search engines, including those relying on sequence databases and those searching spectral libraries. We use cloud computing to deliver the computational power and scientific workflow engines to interface and automate the different processing steps. We show how to leverage these technologies to achieve faster data analysis in proteomics and present three scientific workflows for parallel database as well as spectral library search using our data decomposition programs, X!Tandem and SpectraST.

Parallel Tensor Compression for Large-Scale Scientific Data.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolda, Tamara G.; Ballard, Grey; Austin, Woody Nathan

As parallel computing trends towards the exascale, scientific data produced by high-fidelity simulations are growing increasingly massive. For instance, a simulation on a three-dimensional spatial grid with 512 points per dimension that tracks 64 variables per grid point for 128 time steps yields 8 TB of data. By viewing the data as a dense five way tensor, we can compute a Tucker decomposition to find inherent low-dimensional multilinear structure, achieving compression ratios of up to 10000 on real-world data sets with negligible loss in accuracy. So that we can operate on such massive data, we present the first-ever distributed memorymore » parallel implementation for the Tucker decomposition, whose key computations correspond to parallel linear algebra operations, albeit with nonstandard data layouts. Our approach specifies a data distribution for tensors that avoids any tensor data redistribution, either locally or in parallel. We provide accompanying analysis of the computation and communication costs of the algorithms. To demonstrate the compression and accuracy of the method, we apply our approach to real-world data sets from combustion science simulations. We also provide detailed performance results, including parallel performance in both weak and strong scaling experiments.« less

CO adsorption on (111) and (100) surfaces of the Pt sub 3 Ti alloy. Evidence for parallel binding and strong activation of CO

NASA Technical Reports Server (NTRS)

Mehandru, S. P.; Anderson, A. B.; Ross, P. N.

1985-01-01

The CO adsorption on a 40 atom cluster model of the (111) surface and a 36 atom cluster model of the (100) surface of the Pt3Ti alloy was studied. Parallel binding to high coordinate sites associated with Ti and low CO bond scission barriers are predicted for both surfaces. The binding of CO to Pt sites occurs in an upright orientation. These orientations are a consequence of the nature of the CO pi donation interactions with the surface. On the Ti sites the orbitals donate to the nearly empty Ti 3d band and the antibonding counterpart orbitals are empty. On the Pt sites, however, they are in the filled Pt 5d region of the alloy band, which causes CO to bond in a vertical orientation by 5 delta donation from the carbon end.

Elongate summit calderas as Neogene paleostress indicators in Antarctica

USGS Publications Warehouse

Paulsen, T.S.; Wilson, T.J.

2007-01-01

The orientations and ages of elongate summit calderas on major polygenetic volcanoes were compiled to document Miocene to Pleistocene Sh (minimum horizontal stress) directions on the western and northern flanks of the West Antarctic rift system. Miocene to Pleistocene summit calderas along the western Ross Sea show relatively consistent ENE long axis trends, which are at a high angle to the Transantarctic Mountain Front and parallel to the N77ºE Sh direction at Cape Roberts. The elongation directions of many Miocene to Pleistocene summit calderas in Marie Byrd Land parallel the alignment of polygenetic volcanoes in which they occur, except several Pleistocene calderas with consistent NNE to NE trends. The overall pattern of elongate calderas in Marie Byrd Land is probably due to a combination of structurally controlled orientations and regional stress fields in which Sh is oriented NNE to NE at a moderate to high angle to the trace of the West Antarctic rift system.

Aligned 1-D nanorods of a π-gelator exhibit molecular orientation and excitation energy transport different from entangled fiber networks.

PubMed

Sakakibara, Keita; Chithra, Parayalil; Das, Bidisa; Mori, Taizo; Akada, Misaho; Labuta, Jan; Tsuruoka, Tohru; Maji, Subrata; Furumi, Seiichi; Shrestha, Lok Kumar; Hill, Jonathan P; Acharya, Somobrata; Ariga, Katsuhiko; Ajayaghosh, Ayyappanpillai

2014-06-18

Linear π-gelators self-assemble into entangled fibers in which the molecules are arranged perpendicular to the fiber long axis. However, orientation of gelator molecules in a direction parallel to the long axes of the one-dimensional (1-D) structures remains challenging. Herein we demonstrate that, at the air-water interface, an oligo(p-phenylenevinylene)-derived π-gelator forms aligned nanorods of 340 ± 120 nm length and 34 ± 5 nm width, in which the gelator molecules are reoriented parallel to the long axis of the rods. The orientation change of the molecules results in distinct excited-state properties upon local photoexcitation, as evidenced by near-field scanning optical microscopy. A detailed understanding of the mechanism by which excitation energy migrates through these 1-D molecular assemblies might help in the design of supramolecular structures with improved charge-transport properties.

Exsolution of Ca-clinopyroxene from orthopyroxene aided by deformation

USGS Publications Warehouse

Kirby, S.H.; Etheridge, M.A.

1981-01-01

Monoclinic calcium-poor shear-transformation lamellae and calcium-rich exsolution lamellae occur parallel to (100) in orthopyroxene. The formation of both structures from an orthopyroxene host involves a shear on (100) parallel to [001], with additional cation exchange in the exsolution case. The shear transformation involves a macroscopic simple shear angle of 13.3?? (shear strain of 0.236) and produces a specific a-axis orientation with respect to the sense of shear; we have found that this orientation dominates in exsolution lamellae in kinked orthopyroxene, where the sense of shear is known. In undeformed orthopyroxene, there is generally no preferred sense of orientation of the monoclinic a axes. We advance a specific model for exsolution involving nucleation and growth by shear transformation combined with cation exchange, thus circumventing the classical nucleation barrier and permitting exsolution at lower solute supersaturations. ?? 1981 Springer-Verlag.

Friction Anisotropy with Respect to Topographic Orientation

PubMed Central

Yu, Chengjiao; Wang, Q. Jane

2012-01-01

Friction characteristics with respect to surface topographic orientation were investigated using surfaces of different materials and fabricated with grooves of different scales. Scratching friction tests were conducted using a nano-indentation-scratching system with the tip motion parallel or perpendicular to the groove orientation. Similar friction anisotropy trends were observed for all the surfaces studied, which are (1) under a light load and for surfaces with narrow grooves, the tip motion parallel to the grooves offers higher friction coefficients than does that perpendicular to them, (2) otherwise, equal or lower friction coefficients are found under this motion. The influences of groove size relative to the diameter of the mating tip (as a representative asperity), surface contact stiffness, contact area, and the characteristic stiction length are discussed. The appearance of this friction anisotropy is independent of material; however, the boundary and the point of trend transition depend on material properties. PMID:23248751

Orientation dependence of the dislocation microstructure in compressed body-centered cubic molybdenum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, S.; Wang, M.P.; Chen, C., E-mail: chench011-33@163.com

2014-05-01

The orientation dependence of the deformation microstructure has been investigated in commercial pure molybdenum. After deformation, the dislocation boundaries of compressed molybdenum can be classified, similar to that in face-centered cubic metals, into three types: dislocation cells (Type 2), and extended planar boundaries parallel to (Type 1) or not parallel to (Type 3) a (110) trace. However, it shows a reciprocal relationship between face-centered cubic metals and body-centered cubic metals on the orientation dependence of the deformation microstructure. The higher the strain, the finer the microstructure is and the smaller the inclination angle between extended planar boundaries and the compressionmore » axis is. - Highlights: • A reciprocal relationship between FCC metals and BCC metals is confirmed. • The dislocation boundaries can be classified into three types in compressed Mo. • The dislocation characteristic of different dislocation boundaries is different.« less

Seismic anisotropy and mantle creep in young orogens

USGS Publications Warehouse

Meissner, R.; Mooney, W.D.; Artemieva, I.

2002-01-01

Seismic anisotropy provides evidence for the physical state and tectonic evolution of the lithosphere. We discuss the origin of anisotropy at various depths, and relate it to tectonic stress, geotherms and rheology. The anisotropy of the uppermost mantle is controlled by the orthorhombic mineral olivine, and may result from ductile deformation, dynamic recrystallization or annealing. Anisotropy beneath young orogens has been measured for the seismic phase Pn that propagates in the uppermost mantle. This anisotropy is interpreted as being caused by deformation during the most recent thermotectonic event, and thus provides information on the process of mountain building. Whereas tectonic stress and many structural features in the upper crust are usually orientated perpendicular to the structural axis of mountain belts, Pn anisotropy is aligned parallel to the structural axis. We interpret this to indicate mountain-parallel ductile (i.e. creeping) deformation in the uppermost mantle that is a consequence of mountain-perpendicular compressive stresses. The preferred orientation of the fast axes of some anisotropic minerals, such as olivine, is known to be in the creep direction, a consequence of the anisotropy of strength and viscosity of orientated minerals. In order to explain the anisotropy of the mantle beneath young orogens we extend the concept of crustal 'escape' (or 'extrusion') tectonics to the uppermost mantle. We present rheological model calculations to support this hypothesis. Mountain-perpendicular horizontal stress (determined in the upper crust) and mountain-parallel seismic anisotropy (in the uppermost mantle) require a zone of ductile decoupling in the middle or lower crust of young mountain belts. Examples for stress and mountain-parallel Pn anisotropy are given for Tibet, the Alpine chains, and young mountain ranges in the Americas. Finally, we suggest a simple model for initiating mountain parallel creep.

Fatigue crack growth behavior in equine cortical bone

NASA Astrophysics Data System (ADS)

Shelton, Debbie Renee

2001-07-01

Objectives for this research were to experimentally determine crack growth rates, da/dN, as a function of alternating stress intensity factor, DeltaK, for specimens from lateral and dorsal regions of equine third metacarpal cortical bone tissue, and to determine if the results were described by the Paris law. In one set of experiments, specimens were oriented for crack propagation in the circumferential direction with the crack plane transverse to the long axis of the bone. In the second set of experiments, specimens were oriented for radial crack growth with the crack plane parallel to the long axis of the bone. Results of fatigue tests from the latter specimens were used to evaluate the hypothesis that crack growth rates differ regionally. The final experiments were designed to determine if crack resistance was dependent on region, proportion of hooped osteons (those with circumferentially oriented collagen fibers in the outer lamellae) or number of osteons penetrated by the crack, and to address the hypothesis that hooped osteons resist invasion by cracks better than other osteonal types. The transverse crack growth data for dorsal specimens were described by the Paris law with an exponent of 10.4 and suggested a threshold stress intensity factor, DeltaKth, of 2.0 MPa·m1/2 and fracture toughness of 4.38 MPa·m 1/2. Similar results were not obtained for lateral specimens because the crack always deviated from the intended path and ran parallel to the loading direction. Crack growth for the dorsal and lateral specimens in the radial orientation was described by the Paris law with exponents of 8.7 and 10.2, respectively, and there were no regional differences in the apparent DeltaK th (0.5 MPa·m1/2) or fracture toughness (1.2 MPa·m 1/2). Crack resistance was not associated with cortical region, proportion of hooped osteons or the number of osteons penetrated by the crack. The extent to which cracks penetrate osteons was influenced by whether the collagen fiber orientation in the outer osteon layers was circumferential or longitudinal. The majority of hooped osteons were skirted by the crack. The angle of interaction between the osteon and the crack was also significant in determining whether an osteon was penetrated.

Raising Students' Perception of the Relevance of Science Teaching and Promoting Communication and Evaluation Capabilities Using Authentic and Controversial Socio-Scientific Issues in the Framework of Climate Change

ERIC Educational Resources Information Center

Feierabend, Timo; Eilks, Ingo

2010-01-01

This paper describes the development of different lesson plans dealing with authentic and controversial socio-scientific issues in the framework of climate change. These lesson plans orient themselves along the socio-critical, problem-oriented approach to science teaching. They deal with the use of bioethanol as an alternative fuel and with the…

Object-oriented knowledge representation for expert systems

NASA Technical Reports Server (NTRS)

Scott, Stephen L.

1991-01-01

Object oriented techniques have generated considerable interest in the Artificial Intelligence (AI) community in recent years. This paper discusses an approach for representing expert system knowledge using classes, objects, and message passing. The implementation is in version 4.3 of NASA's C Language Integrated Production System (CLIPS), an expert system tool that does not provide direct support for object oriented design. The method uses programmer imposed conventions and keywords to structure facts, and rules to provide object oriented capabilities.

Field characterization of elastic properties across a fault zone reactivated by fluid injection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeanne, Pierre; Guglielmi, Yves; Rutqvist, Jonny

In this paper, we studied the elastic properties of a fault zone intersecting the Opalinus Clay formation at 300 m depth in the Mont Terri Underground Research Laboratory (Switzerland). Four controlled water injection experiments were performed in borehole straddle intervals set at successive locations across the fault zone. A three-component displacement sensor, which allowed capturing the borehole wall movements during injection, was used to estimate the elastic properties of representative locations across the fault zone, from the host rock to the damage zone to the fault core. Young's moduli were estimated by both an analytical approach and numerical finite differencemore » modeling. Results show a decrease in Young's modulus from the host rock to the damage zone by a factor of 5 and from the damage zone to the fault core by a factor of 2. In the host rock, our results are in reasonable agreement with laboratory data showing a strong elastic anisotropy characterized by the direction of the plane of isotropy parallel to the laminar structure of the shale formation. In the fault zone, strong rotations of the direction of anisotropy can be observed. Finally, the plane of isotropy can be oriented either parallel to bedding (when few discontinuities are present), parallel to the direction of the main fracture family intersecting the zone, and possibly oriented parallel or perpendicular to the fractures critically oriented for shear reactivation (when repeated past rupture along this plane has created a zone).« less

Field characterization of elastic properties across a fault zone reactivated by fluid injection

DOE PAGES

Jeanne, Pierre; Guglielmi, Yves; Rutqvist, Jonny; ...

2017-08-12

In this paper, we studied the elastic properties of a fault zone intersecting the Opalinus Clay formation at 300 m depth in the Mont Terri Underground Research Laboratory (Switzerland). Four controlled water injection experiments were performed in borehole straddle intervals set at successive locations across the fault zone. A three-component displacement sensor, which allowed capturing the borehole wall movements during injection, was used to estimate the elastic properties of representative locations across the fault zone, from the host rock to the damage zone to the fault core. Young's moduli were estimated by both an analytical approach and numerical finite differencemore » modeling. Results show a decrease in Young's modulus from the host rock to the damage zone by a factor of 5 and from the damage zone to the fault core by a factor of 2. In the host rock, our results are in reasonable agreement with laboratory data showing a strong elastic anisotropy characterized by the direction of the plane of isotropy parallel to the laminar structure of the shale formation. In the fault zone, strong rotations of the direction of anisotropy can be observed. Finally, the plane of isotropy can be oriented either parallel to bedding (when few discontinuities are present), parallel to the direction of the main fracture family intersecting the zone, and possibly oriented parallel or perpendicular to the fractures critically oriented for shear reactivation (when repeated past rupture along this plane has created a zone).« less

Object-oriented numerical computing C++

NASA Technical Reports Server (NTRS)

Vanrosendale, John

1994-01-01

An object oriented language is one allowing users to create a set of related types and then intermix and manipulate values of these related types. This paper discusses object oriented numerical computing using C++.

Historical and cultural aspects of the pineal gland: comparison between the theories provided by Spiritism in the 1940s and the current scientific evidence.

PubMed

Lucchetti, Giancarlo; Daher, Jorge C; Iandoli, Decio; Gonçalves, Juliane P B; Lucchetti, Alessandra L G

2013-01-01

Significance has been attached to the pineal gland in numerous different cultures and beliefs. One religion that has advanced the role of the pineal gland is Spiritism. The objective of the present study was to compile information on the pineal gland drawing on the books of Francisco Cândido Xavier written through psychography and to carry out a critical analysis of their scientific bases by comparing against evidence in the current scientific literature. A systematic search using the terms "pineal gland" and "epiphysis" was conducted of 12 works allegedly dictated by the spirit "André Luiz". All information on the pineal having potential correlation with the field of medicine and current studies was included. Specialists in the area were recruited to compile the information and draw parallels with the scientific literature. The themes related to the pineal gland were: mental health, reproductive function, endocrinology, relationship with physical activity, spiritual connection, criticism of the theory that the organ exerts no function, and description of a hormone secreted by the gland (reference alluding to melatonin, isolated 13 years later). The historical background for each theme was outlined, together with the theories present in the Spiritist books and in the relevant scientific literature. The present article provides an analysis of the knowledge the scientific community can acquire from the history of humanity and from science itself. The process of formulating hypotheses and scientific theories can benefit by drawing on the cultural aspects of civilization, taking into account so-called non-traditional reports and theories.

System and method for representing and manipulating three-dimensional objects on massively parallel architectures

DOEpatents

Karasick, M.S.; Strip, D.R.

1996-01-30

A parallel computing system is described that comprises a plurality of uniquely labeled, parallel processors, each processor capable of modeling a three-dimensional object that includes a plurality of vertices, faces and edges. The system comprises a front-end processor for issuing a modeling command to the parallel processors, relating to a three-dimensional object. Each parallel processor, in response to the command and through the use of its own unique label, creates a directed-edge (d-edge) data structure that uniquely relates an edge of the three-dimensional object to one face of the object. Each d-edge data structure at least includes vertex descriptions of the edge and a description of the one face. As a result, each processor, in response to the modeling command, operates upon a small component of the model and generates results, in parallel with all other processors, without the need for processor-to-processor intercommunication. 8 figs.

Postural and Object-Oriented Experiences Advance Early Reaching, Object Exploration, and Means-End Behavior

ERIC Educational Resources Information Center

Lobo, Michele A.; Galloway, James C.

2008-01-01

The effects of 3 weeks of social (control), postural, or object-oriented experiences on 9- to 21-week-old infants' (N = 42) reaching, exploration, and means-end behaviors were assessed. Coders recorded object contacts, mouthing, fingering, attention, and affect from video. Postural and object-oriented experiences advanced reaching, haptic…

Object-oriented programming with mixins in Ada

NASA Technical Reports Server (NTRS)

Seidewitz, ED

1992-01-01

Recently, I wrote a paper discussing the lack of 'true' object-oriented programming language features in Ada 83, why one might desire them in Ada, and how they might be added in Ada 9X. The approach I took in this paper was to build the new object-oriented features of Ada 9X as much as possible on the basic constructs and philosophy of Ada 83. The object-oriented features proposed for Ada 9X, while different in detail, are based on the same kind of approach. Further consideration of this approach led me on a long reflection on the nature of object-oriented programming and its application to Ada. The results of this reflection, presented in this paper, show how a fairly natural object-oriented style can indeed be developed even in Ada 83. The exercise of developing this style is useful for at least three reasons: (1) it provides a useful style for programming object-oriented applications in Ada 83 until new features become available with Ada 9X; (2) it demystifies many of the mechanisms that seem to be 'magic' in most object-oriented programming languages by making them explicit; and (3) it points out areas that are and are not in need of change in Ada 83 to make object-oriented programming more natural in Ada 9X. In the next four sections I will address in turn the issues of object-oriented classes, mixins, self-reference and supertyping. The presentation is through a sequence of examples. This results in some overlap with that paper, but all the examples in the present paper are written entirely in Ada 83. I will return to considerations for Ada 9X in the last section of the paper.

Techniques and Tools for Performance Tuning of Parallel and Distributed Scientific Applications

NASA Technical Reports Server (NTRS)

Sarukkai, Sekhar R.; VanderWijngaart, Rob F.; Castagnera, Karen (Technical Monitor)

1994-01-01

Performance degradation in scientific computing on parallel and distributed computer systems can be caused by numerous factors. In this half-day tutorial we explain what are the important methodological issues involved in obtaining codes that have good performance potential. Then we discuss what are the possible obstacles in realizing that potential on contemporary hardware platforms, and give an overview of the software tools currently available for identifying the performance bottlenecks. Finally, some realistic examples are used to illustrate the actual use and utility of such tools.

File-access characteristics of parallel scientific workloads

NASA Technical Reports Server (NTRS)

Nieuwejaar, Nils; Kotz, David; Purakayastha, Apratim; Best, Michael; Ellis, Carla Schlatter

1995-01-01

Phenomenal improvements in the computational performance of multiprocessors have not been matched by comparable gains in I/O system performance. This imbalance has resulted in I/O becoming a significant bottleneck for many scientific applications. One key to overcoming this bottleneck is improving the performance of parallel file systems. The design of a high-performance parallel file system requires a comprehensive understanding of the expected workload. Unfortunately, until recently, no general workload studies of parallel file systems have been conducted. The goal of the CHARISMA project was to remedy this problem by characterizing the behavior of several production workloads, on different machines, at the level of individual reads and writes. The first set of results from the CHARISMA project describe the workloads observed on an Intel iPSC/860 and a Thinking Machines CM-5. This paper is intended to compare and contrast these two workloads for an understanding of their essential similarities and differences, isolating common trends and platform-dependent variances. Using this comparison, we are able to gain more insight into the general principles that should guide parallel file-system design.

Effect of nanostructures orientation on electroosmotic flow in a microfluidic channel

NASA Astrophysics Data System (ADS)

Eng Lim, An; Lim, Chun Yee; Cheong Lam, Yee; Taboryski, Rafael; Rui Wang, Shu

2017-06-01

Electroosmotic flow (EOF) is an electric-field-induced fluid flow that has numerous micro-/nanofluidic applications, ranging from pumping to chemical and biomedical analyses. Nanoscale networks/structures are often integrated in microchannels for a broad range of applications, such as electrophoretic separation of biomolecules, high reaction efficiency catalytic microreactors, and enhancement of heat transfer and sensing. Their introduction has been known to reduce EOF. Hitherto, a proper study on the effect of nanostructures orientation on EOF in a microfluidic channel is yet to be carried out. In this investigation, we present a novel fabrication method for nanostructure designs that possess maximum orientation difference, i.e. parallel versus perpendicular indented nanolines, to examine the effect of nanostructures orientation on EOF. It consists of four phases: fabrication of silicon master, creation of mold insert via electroplating, injection molding with cyclic olefin copolymer, and thermal bonding and integration of practical inlet/outlet ports. The effect of nanostructures orientation on EOF was studied experimentally by current monitoring method. The experimental results show that nanolines which are perpendicular to the microchannel reduce the EOF velocity significantly (approximately 20%). This flow velocity reduction is due to the distortion of local electric field by the perpendicular nanolines at the nanostructured surface as demonstrated by finite element simulation. In contrast, nanolines which are parallel to the microchannel have no effect on EOF, as it can be deduced that the parallel nanolines do not distort the local electric field. The outcomes of this investigation contribute to the precise control of EOF in lab-on-chip devices, and fundamental understanding of EOF in devices which utilize nanostructured surfaces for chemical and biological analyses.

Interfacial Structures of Trihexyltetradecylphosphonium-bis(mandelato)borate Ionic Liquid Confined between Gold Electrodes.

PubMed

Wang, Yong-Lei; Golets, Mikhail; Li, Bin; Sarman, Sten; Laaksonen, Aatto

2017-02-08

Atomistic molecular dynamics simulations have been performed to study microscopic the interfacial ionic structures, molecular arrangements, and orientational preferences of trihexyltetradecylphosphonium-bis(mandelato)borate ([P 6,6,6,14 ][BMB]) ionic liquid confined between neutral and charged gold electrodes. It was found that both [P 6,6,6,14 ] cations and [BMB] anions are coabsorbed onto neutral electrodes at different temperatures. The hexyl and tetradecyl chains in [P 6,6,6,14 ] cations lie preferentially flat on neutral electrodes. The oxalato and phenyl rings in [BMB] anions are characterized by alternative parallel-perpendicular orientations in the mixed innermost ionic layer adjacent to neutral electrodes. An increase in temperature has a marginal effect on the interfacial ionic structures and molecular orientations of [P 6,6,6,14 ][BMB] ionic species in a confined environment. Electrifying gold electrodes leads to peculiar changes in the interfacial ionic structures and molecular orientational arrangements of [P 6,6,6,14 ] cations and [BMB] anions in negatively and positively charged gold electrodes, respectively. As surface charge density increases (but lower than 20 μC/cm 2 ), the layer thickness of the mixed innermost interfacial layer gradually increases due to a consecutive accumulation of [P 6,6,6,14 ] cations and [BMB] anions at negatively and positively charged electrodes, respectively, before the formation of distinct cationic and anionic innermost layers. Meanwhile, the molecular orientations of two oxalato rings in the same [BMB] anions change gradually from a parallel-perpendicular feature to being partially characterized by a tilted arrangement at an angle of 45° from the electrodes and finally to a dominant parallel coordination pattern along positively charged electrodes. Distinctive interfacial distribution patterns are also observed accordingly for phenyl rings that are directly connected to neighboring oxalato rings in [BMB] anions.

Predicting helix orientation for coiled-coil dimers

PubMed Central

Apgar, James R.; Gutwin, Karl N.; Keating, Amy E.

2008-01-01

The alpha-helical coiled coil is a structurally simple protein oligomerization or interaction motif consisting of two or more alpha helices twisted into a supercoiled bundle. Coiled coils can differ in their stoichiometry, helix orientation and axial alignment. Because of the near degeneracy of many of these variants, coiled coils pose a challenge to fold recognition methods for structure prediction. Whereas distinctions between some protein folds can be discriminated on the basis of hydrophobic/polar patterning or secondary structure propensities, the sequence differences that encode important details of coiled-coil structure can be subtle. This is emblematic of a larger problem in the field of protein structure and interaction prediction: that of establishing specificity between closely similar structures. We tested the behavior of different computational models on the problem of recognizing the correct orientation - parallel vs. antiparallel - of pairs of alpha helices that can form a dimeric coiled coil. For each of 131 examples of known structure, we constructed a large number of both parallel and antiparallel structural models and used these to asses the ability of five energy functions to recognize the correct fold. We also developed and tested three sequenced-based approaches that make use of varying degrees of implicit structural information. The best structural methods performed similarly to the best sequence methods, correctly categorizing ∼81% of dimers. Steric compatibility with the fold was important for some coiled coils we investigated. For many examples, the correct orientation was determined by smaller energy differences between parallel and antiparallel structures distributed over many residues and energy components. Prediction methods that used structure but incorporated varying approximations and assumptions showed quite different behaviors when used to investigate energetic contributions to orientation preference. Sequence based methods were sensitive to the choice of residue-pair interactions scored. PMID:18506779

Towards an Object-Oriented Model for the Design and Development of Learning Objects

ERIC Educational Resources Information Center

Chrysostomou, Chrysostomos; Papadopoulos, George

2008-01-01

This work introduces the concept of an Object-Oriented Learning Object (OOLO) that is developed in a manner similar to the one that software objects are developed through Object-Oriented Software Engineering (OO SWE) techniques. In order to make the application of the OOLO feasible and efficient, an OOLO model needs to be developed based on…

Correction of radiographic measurements of acetabular cup wear for variations in pelvis orientation.

PubMed

Derbyshire, Brian

2018-03-01

Radiographic measurement of two-dimensional acetabular cup wear is usually carried out on a series of follow-up radiographs of the patient's pelvis. Since the orientation of the pelvis might not be consistent at every X-ray examination, the resulting change in view of the wear plane introduces error into the linear wear measurement. This effect is amplified on some designs of cup in which the centre of the socket is several millimetres below the centre of the cup or circular wire marker. This study describes the formulation of a mathematical method to correct radiographic wear measurements for changes in pelvis orientation. A mathematical simulation of changes in cup orientation and wear vectors caused by pelvic tilt was used to confirm that the formulae corrected the wear exactly if the radiographic plane of the reference radiograph was parallel to the true plane of wear. An error analysis showed that even when the true wear plane was not parallel to the reference radiographic plane, the formulae could still provide a useful correction. A published correction formula was found to be ineffective.

Correction of radiographic measurements of acetabular cup wear for variations in pelvis orientation

PubMed Central

Derbyshire, Brian

2018-01-01

Radiographic measurement of two-dimensional acetabular cup wear is usually carried out on a series of follow-up radiographs of the patient’s pelvis. Since the orientation of the pelvis might not be consistent at every X-ray examination, the resulting change in view of the wear plane introduces error into the linear wear measurement. This effect is amplified on some designs of cup in which the centre of the socket is several millimetres below the centre of the cup or circular wire marker. This study describes the formulation of a mathematical method to correct radiographic wear measurements for changes in pelvis orientation. A mathematical simulation of changes in cup orientation and wear vectors caused by pelvic tilt was used to confirm that the formulae corrected the wear exactly if the radiographic plane of the reference radiograph was parallel to the true plane of wear. An error analysis showed that even when the true wear plane was not parallel to the reference radiographic plane, the formulae could still provide a useful correction. A published correction formula was found to be ineffective. PMID:29473454

Effect of Aerogel Anisotropy in Superfluid 3He-A

NASA Astrophysics Data System (ADS)

Zimmerman, A. M.; Li, J. I. A.; Pollanen, J.; Collett, C. A.; Gannon, W. J.; Halperin, W. P.

2014-03-01

Two theories have been advanced to describe the effects of anisotropic impurity introduced by stretched silica aerogel on the orientation of the orbital angular momentum l& circ; in superfluid 3He-A. These theories disagree on whether the anisotropy will orient l& circ; perpendicular[2] or parallel[3] to the strain axis. In order to examine this question we have produced and characterized a homogeneous aerogel sample with uniaxial anisotropy introduced during growth, corresponding to stretching of the aerogel. These samples have been shown to stabilize two new chiral states;[4] the higher temperature state being the subject of the present study. Using pulsed NMR we have performed experiments on 3He-A imbibed in this sample in two orientations: strain parallel and perpendicular to the applied magnetic field. From the NMR frequency shifts as a function of tip angle and temperature, we find that the angular momentum l& circ; is oriented along the strain axis, providing evidence for the theory advanced by Sauls. This work was supported by the National Science Foundation, DMR-1103625.

Agile parallel bioinformatics workflow management using Pwrake.

PubMed

Mishima, Hiroyuki; Sasaki, Kensaku; Tanaka, Masahiro; Tatebe, Osamu; Yoshiura, Koh-Ichiro

2011-09-08

In bioinformatics projects, scientific workflow systems are widely used to manage computational procedures. Full-featured workflow systems have been proposed to fulfil the demand for workflow management. However, such systems tend to be over-weighted for actual bioinformatics practices. We realize that quick deployment of cutting-edge software implementing advanced algorithms and data formats, and continuous adaptation to changes in computational resources and the environment are often prioritized in scientific workflow management. These features have a greater affinity with the agile software development method through iterative development phases after trial and error.Here, we show the application of a scientific workflow system Pwrake to bioinformatics workflows. Pwrake is a parallel workflow extension of Ruby's standard build tool Rake, the flexibility of which has been demonstrated in the astronomy domain. Therefore, we hypothesize that Pwrake also has advantages in actual bioinformatics workflows. We implemented the Pwrake workflows to process next generation sequencing data using the Genomic Analysis Toolkit (GATK) and Dindel. GATK and Dindel workflows are typical examples of sequential and parallel workflows, respectively. We found that in practice, actual scientific workflow development iterates over two phases, the workflow definition phase and the parameter adjustment phase. We introduced separate workflow definitions to help focus on each of the two developmental phases, as well as helper methods to simplify the descriptions. This approach increased iterative development efficiency. Moreover, we implemented combined workflows to demonstrate modularity of the GATK and Dindel workflows. Pwrake enables agile management of scientific workflows in the bioinformatics domain. The internal domain specific language design built on Ruby gives the flexibility of rakefiles for writing scientific workflows. Furthermore, readability and maintainability of rakefiles may facilitate sharing workflows among the scientific community. Workflows for GATK and Dindel are available at http://github.com/misshie/Workflows.

Agile parallel bioinformatics workflow management using Pwrake

PubMed Central

2011-01-01

Background In bioinformatics projects, scientific workflow systems are widely used to manage computational procedures. Full-featured workflow systems have been proposed to fulfil the demand for workflow management. However, such systems tend to be over-weighted for actual bioinformatics practices. We realize that quick deployment of cutting-edge software implementing advanced algorithms and data formats, and continuous adaptation to changes in computational resources and the environment are often prioritized in scientific workflow management. These features have a greater affinity with the agile software development method through iterative development phases after trial and error. Here, we show the application of a scientific workflow system Pwrake to bioinformatics workflows. Pwrake is a parallel workflow extension of Ruby's standard build tool Rake, the flexibility of which has been demonstrated in the astronomy domain. Therefore, we hypothesize that Pwrake also has advantages in actual bioinformatics workflows. Findings We implemented the Pwrake workflows to process next generation sequencing data using the Genomic Analysis Toolkit (GATK) and Dindel. GATK and Dindel workflows are typical examples of sequential and parallel workflows, respectively. We found that in practice, actual scientific workflow development iterates over two phases, the workflow definition phase and the parameter adjustment phase. We introduced separate workflow definitions to help focus on each of the two developmental phases, as well as helper methods to simplify the descriptions. This approach increased iterative development efficiency. Moreover, we implemented combined workflows to demonstrate modularity of the GATK and Dindel workflows. Conclusions Pwrake enables agile management of scientific workflows in the bioinformatics domain. The internal domain specific language design built on Ruby gives the flexibility of rakefiles for writing scientific workflows. Furthermore, readability and maintainability of rakefiles may facilitate sharing workflows among the scientific community. Workflows for GATK and Dindel are available at http://github.com/misshie/Workflows. PMID:21899774

Stage Cylindrical Immersive Display

NASA Technical Reports Server (NTRS)

Abramyan, Lucy; Norris, Jeffrey S.; Powell, Mark W.; Mittman, David S.; Shams, Khawaja S.

2011-01-01

Panoramic images with a wide field of view intend to provide a better understanding of an environment by placing objects of the environment on one seamless image. However, understanding the sizes and relative positions of the objects in a panorama is not intuitive and prone to errors because the field of view is unnatural to human perception. Scientists are often faced with the difficult task of interpreting the sizes and relative positions of objects in an environment when viewing an image of the environment on computer monitors or prints. A panorama can display an object that appears to be to the right of the viewer when it is, in fact, behind the viewer. This misinterpretation can be very costly, especially when the environment is remote and/or only accessible by unmanned vehicles. A 270 cylindrical display has been developed that surrounds the viewer with carefully calibrated panoramic imagery that correctly engages their natural kinesthetic senses and provides a more accurate awareness of the environment. The cylindrical immersive display offers a more natural window to the environment than a standard cubic CAVE (Cave Automatic Virtual Environment), and the geometry allows multiple collocated users to simultaneously view data and share important decision-making tasks. A CAVE is an immersive virtual reality environment that allows one or more users to absorb themselves in a virtual environment. A common CAVE setup is a room-sized cube where the cube sides act as projection planes. By nature, all cubic CAVEs face a problem with edge matching at edges and corners of the display. Modern immersive displays have found ways to minimize seams by creating very tight edges, and rely on the user to ignore the seam. One significant deficiency of flat-walled CAVEs is that the sense of orientation and perspective within the scene is broken across adjacent walls. On any single wall, parallel lines properly converge at their vanishing point as they should, and the sense of perspective within the scene contained on only one wall has integrity. Unfortunately, parallel lines that lie on adjacent walls do not necessarily remain parallel. This results in inaccuracies in the scene that can distract the viewer and subtract from the immersive experience of the CAVE.

A Randomized Double-Blinded Trial on the Effects of Ultrasound Transducer Orientation on Teaching and Learning Ultrasound-Guided Regional Anesthesia.

PubMed

Lam, Nicholas C K; Baker, Elizabeth B; Fishburn, Steven J; Hammer, Angie R; Petersen, Timothy R; Mariano, Edward R

2016-07-01

Learning ultrasound-guided regional anesthesia skills, especially needle/ beam alignment, can be especially difficulty for trainees, who can often become frustrated. We hypothesized that teaching novices to orient the transducer and needle perpendicular to their shoulders will improve performance on a standardized task, compared to holding the transducer and needle parallel to the shoulders. This study compared the effects of transducer orientation on trainees' ability to complete a standardized ultrasound-guided nerve block simulation. The time to task completion and percentage of the attempt time without adequate needle visualization were measured. Participants were right-handed healthy adults with no previous ultrasound experience and were randomly assigned to training in either transducer and needle alignment in a coronal plane, parallel to the shoulders (parallel group) or transducer and needle alignment in a sagittal plane, perpendicular to the shoulders (perpendicular group). Participants used ultrasound to direct a needle to 3 targets in a standardized gelatin phantom and repeated this task 3 times. Their efforts were timed and evaluated by an assessor, who was blinded to group assignment. Data were analyzed on 28 participants. The perpendicular group was able to complete the task more quickly (P < .001) and with a smaller proportion of time lost to inadequate needle visualization (P < .001). Ultrasound-guided regional anesthesia trainees complete a standardized task more quickly and efficiently when instructed to hold the transducer and needle in an orientation perpendicular to their shoulders.

Integration of object-oriented knowledge representation with the CLIPS rule based system

NASA Technical Reports Server (NTRS)

Logie, David S.; Kamil, Hasan

1990-01-01

The paper describes a portion of the work aimed at developing an integrated, knowledge based environment for the development of engineering-oriented applications. An Object Representation Language (ORL) was implemented in C++ which is used to build and modify an object-oriented knowledge base. The ORL was designed in such a way so as to be easily integrated with other representation schemes that could effectively reason with the object base. Specifically, the integration of the ORL with the rule based system C Language Production Systems (CLIPS), developed at the NASA Johnson Space Center, will be discussed. The object-oriented knowledge representation provides a natural means of representing problem data as a collection of related objects. Objects are comprised of descriptive properties and interrelationships. The object-oriented model promotes efficient handling of the problem data by allowing knowledge to be encapsulated in objects. Data is inherited through an object network via the relationship links. Together, the two schemes complement each other in that the object-oriented approach efficiently handles problem data while the rule based knowledge is used to simulate the reasoning process. Alone, the object based knowledge is little more than an object-oriented data storage scheme; however, the CLIPS inference engine adds the mechanism to directly and automatically reason with that knowledge. In this hybrid scheme, the expert system dynamically queries for data and can modify the object base with complete access to all the functionality of the ORL from rules.

Object-oriented productivity metrics

NASA Technical Reports Server (NTRS)

Connell, John L.; Eller, Nancy

1992-01-01

Software productivity metrics are useful for sizing and costing proposed software and for measuring development productivity. Estimating and measuring source lines of code (SLOC) has proven to be a bad idea because it encourages writing more lines of code and using lower level languages. Function Point Analysis is an improved software metric system, but it is not compatible with newer rapid prototyping and object-oriented approaches to software development. A process is presented here for counting object-oriented effort points, based on a preliminary object-oriented analysis. It is proposed that this approach is compatible with object-oriented analysis, design, programming, and rapid prototyping. Statistics gathered on actual projects are presented to validate the approach.

Object-oriented analysis and design of an ECG storage and retrieval system integrated with an HIS.

PubMed

Wang, C; Ohe, K; Sakurai, T; Nagase, T; Kaihara, S

1996-03-01

For a hospital information system, object-oriented methodology plays an increasingly important role, especially for the management of digitized data, e.g., the electrocardiogram, electroencephalogram, electromyogram, spirogram, X-ray, CT and histopathological images, which are not yet computerized in most hospitals. As a first step in an object-oriented approach to hospital information management and storing medical data in an object-oriented database, we connected electrocardiographs to a hospital network and established the integration of ECG storage and retrieval systems with a hospital information system. In this paper, the object-oriented analysis and design of the ECG storage and retrieval systems is reported.

Lineation-parallel c-axis Fabric of Quartz Formed Under Water-rich Conditions

NASA Astrophysics Data System (ADS)

Wang, Y.; Zhang, J.; Li, P.

2014-12-01

The crystallographic preferred orientation (CPO) of quartz is of great significance because it records much valuable information pertinent to the deformation of quartz-rich rocks in the continental crust. The lineation-parallel c-axis CPO (i.e., c-axis forming a maximum parallel to the lineation) in naturally deformed quartz is generally considered to form under high temperature (> ~550 ºC) conditions. However, most laboratory deformation experiments on quartzite failed to produce such a CPO at high temperatures up to 1200 ºC. Here we reported a new occurrence of the lineation-parallel c-axis CPO of quartz from kyanite-quartz veins in eclogite. Optical microstructural observations, fourier transform infrared (FTIR) and electron backscattered diffraction (EBSD) techniques were integrated to illuminate the nature of quartz CPOs. Quartz exhibits mostly straight to slightly curved grain boundaries, modest intracrystalline plasticity, and significant shape preferred orientation (SPO) and CPOs, indicating dislocation creep dominated the deformation of quartz. Kyanite grains in the veins are mostly strain-free, suggestive of their higher strength than quartz. The pronounced SPO and CPOs in kyanite were interpreted to originate from anisotropic crystal growth and/or mechanical rotation during vein-parallel shearing. FTIR results show quartz contains a trivial amount of structurally bound water (several tens of H/106 Si), while kyanite has a water content of 384-729 H/106 Si; however, petrographic observations suggest quartz from the veins were practically deformed under water-rich conditions. We argue that the observed lineation-parallel c-axis fabric in quartz was inherited from preexisting CPOs as a result of anisotropic grain growth under stress facilitated by water, but rather than due to a dominant c-slip. The preservation of the quartz CPOs probably benefited from the preexisting quartz CPOs which renders most quartz grains unsuitably oriented for an easy a-slip at lower temperatures and the weak deformation during subsequent exhumation. This hypothesis provides a reasonable explanation for the observations that most lineation-parallel c-axis fabrics of quartz were found in veins and that deformation experiments on quartz-rich rocks at high temperature failed to produce such CPOs.

Foveal analysis and peripheral selection during active visual sampling

PubMed Central

Ludwig, Casimir J. H.; Davies, J. Rhys; Eckstein, Miguel P.

2014-01-01

Human vision is an active process in which information is sampled during brief periods of stable fixation in between gaze shifts. Foveal analysis serves to identify the currently fixated object and has to be coordinated with a peripheral selection process of the next fixation location. Models of visual search and scene perception typically focus on the latter, without considering foveal processing requirements. We developed a dual-task noise classification technique that enables identification of the information uptake for foveal analysis and peripheral selection within a single fixation. Human observers had to use foveal vision to extract visual feature information (orientation) from different locations for a psychophysical comparison. The selection of to-be-fixated locations was guided by a different feature (luminance contrast). We inserted noise in both visual features and identified the uptake of information by looking at correlations between the noise at different points in time and behavior. Our data show that foveal analysis and peripheral selection proceeded completely in parallel. Peripheral processing stopped some time before the onset of an eye movement, but foveal analysis continued during this period. Variations in the difficulty of foveal processing did not influence the uptake of peripheral information and the efficacy of peripheral selection, suggesting that foveal analysis and peripheral selection operated independently. These results provide important theoretical constraints on how to model target selection in conjunction with foveal object identification: in parallel and independently. PMID:24385588

Anisotropy of magnetic susceptibility studies in Tertiary ridge-parallel dykes (Iceland), Tertiary margin-normal Aishihik dykes (Yukon), and Proterozoic Kenora Kabetogama composite dykes (Minnesota and Ontario)

NASA Astrophysics Data System (ADS)

Craddock, John P.; Kennedy, Bryan C.; Cook, Avery L.; Pawlisch, Melissa S.; Johnston, Stephen T.; Jackson, Mike

2008-02-01

Mafic dykes of different ages were collected from three different tectonic settings and analyzed using anisotropy of magnetic susceptibility (AMS) as a proxy for magmatic flow during intrusion. In Iceland, ridge-parallel basaltic dykes were sampled on each side of the active tectonic boundary. The dykes are < 10 m wide along a 1-2 km strike, and are the result of a single intrusion from 1-2 km deep magma chambers in oceanic crust. Thirteen samples were collected (7 N. American plate; 6 European) and 153 cores were analyzed by AMS and preserve a vertical Kmax orientation indicating vertical emplacement. The Eocene Aishihik dyke swarm intrudes the Yukon-Tanana terrane in the Yukon province, Canada over an area ~ 200 by 60 km. These dykes were intruded normal to the accretionary margin, are porphyritic andesites, and have an intermediate geochemical signature based on major and trace element analyses. Ten dykes were sampled and 111 cores analyzed using AMS, and the dykes preserve a vertical Kmax orientation, indicating intrusion was vertical through ~ 30 km of continental crust. The 2.06 Ga Kenora-Kabetogama dykes in northern Minnesota and western Ontario crosscut a variety of Archean terranes (thickness ~ 50 km) in a radiating pattern. The unmetamorphosed basaltic dykes are 1-120 m wide, 10-110 km in length, are vertical in orientation and can be grouped as either being single intrusion or multiple intrusion (composite) dykes. AMS data preserve a vertical Kmax orientation for the southerly locations (2 dykes, n = 53) and horizontal Kmax for the remainder to the northwest (15 dykes, n = 194). Maximum magnetic susceptibility axes (4 dykes, n = 92) for composite dykes are scattered and yield inconsistent flow directions with regard to the dyke margin. Almost all of our results are "normal" in that, the magnetic foliation (the plane containing Kmax and Kint, normal to Kmin) is parallel to the dyke planes, which gives us confidence that the magnetic lineations (i.e., Kmax orientations) are parallel to magmatic flow.

Accuracy analysis and design of A3 parallel spindle head

NASA Astrophysics Data System (ADS)

Ni, Yanbing; Zhang, Biao; Sun, Yupeng; Zhang, Yuan

2016-03-01

As functional components of machine tools, parallel mechanisms are widely used in high efficiency machining of aviation components, and accuracy is one of the critical technical indexes. Lots of researchers have focused on the accuracy problem of parallel mechanisms, but in terms of controlling the errors and improving the accuracy in the stage of design and manufacturing, further efforts are required. Aiming at the accuracy design of a 3-DOF parallel spindle head(A3 head), its error model, sensitivity analysis and tolerance allocation are investigated. Based on the inverse kinematic analysis, the error model of A3 head is established by using the first-order perturbation theory and vector chain method. According to the mapping property of motion and constraint Jacobian matrix, the compensatable and uncompensatable error sources which affect the accuracy in the end-effector are separated. Furthermore, sensitivity analysis is performed on the uncompensatable error sources. The sensitivity probabilistic model is established and the global sensitivity index is proposed to analyze the influence of the uncompensatable error sources on the accuracy in the end-effector of the mechanism. The results show that orientation error sources have bigger effect on the accuracy in the end-effector. Based upon the sensitivity analysis results, the tolerance design is converted into the issue of nonlinearly constrained optimization with the manufacturing cost minimum being the optimization objective. By utilizing the genetic algorithm, the allocation of the tolerances on each component is finally determined. According to the tolerance allocation results, the tolerance ranges of ten kinds of geometric error sources are obtained. These research achievements can provide fundamental guidelines for component manufacturing and assembly of this kind of parallel mechanisms.

Comparison of Educators' and Industrial Managers' Work Motivation Using Parallel Forms of the Work Components Study Questionnaire.

ERIC Educational Resources Information Center

Thornton, Billy W.; And Others

The idea that educators would differ from business managers on Herzberg's motivation factors and Blum's security orientations was posited. Parallel questionnaires were used to measure the motivational variables. The sample was composed of 432 teachers, 118 administrators, and 192 industrial managers. Data were analyzed using multivariate and…

Turbomachinery CFD on parallel computers

NASA Technical Reports Server (NTRS)

Blech, Richard A.; Milner, Edward J.; Quealy, Angela; Townsend, Scott E.

1992-01-01

The role of multistage turbomachinery simulation in the development of propulsion system models is discussed. Particularly, the need for simulations with higher fidelity and faster turnaround time is highlighted. It is shown how such fast simulations can be used in engineering-oriented environments. The use of parallel processing to achieve the required turnaround times is discussed. Current work by several researchers in this area is summarized. Parallel turbomachinery CFD research at the NASA Lewis Research Center is then highlighted. These efforts are focused on implementing the average-passage turbomachinery model on MIMD, distributed memory parallel computers. Performance results are given for inviscid, single blade row and viscous, multistage applications on several parallel computers, including networked workstations.

The Snow Data System at NASA JPL

NASA Astrophysics Data System (ADS)

Horn, J.; Painter, T. H.; Bormann, K. J.; Rittger, K.; Brodzik, M. J.; Skiles, M.; Burgess, A. B.; Mattmann, C. A.; Ramirez, P.; Joyce, M.; Goodale, C. E.; McGibbney, L. J.; Zimdars, P.; Yaghoobi, R.

2017-12-01

The Snow Data System at NASA JPL includes data processing pipelines built with open source software, Apache 'Object Oriented Data Technology' (OODT). Processing is carried out in parallel across a high-powered computing cluster. The pipelines use input data from satellites such as MODIS, VIIRS and Landsat. They apply algorithms to the input data to produce a variety of outputs in GeoTIFF format. These outputs include daily data for SCAG (Snow Cover And Grain size) and DRFS (Dust Radiative Forcing in Snow), along with 8-day composites and MODICE annual minimum snow and ice calculations. This poster will describe the Snow Data System, its outputs and their uses and applications. It will also highlight recent advancements to the system and plans for the future.

The Snow Data System at NASA JPL

NASA Astrophysics Data System (ADS)

Joyce, M.; Laidlaw, R.; Painter, T. H.; Bormann, K. J.; Rittger, K.; Brodzik, M. J.; Skiles, M.; Burgess, A. B.; Mattmann, C. A.; Ramirez, P.; Goodale, C. E.; McGibbney, L. J.; Zimdars, P.; Yaghoobi, R.

2016-12-01

The Snow Data System at NASA JPL includes data processing pipelines built with open source software, Apache 'Object Oriented Data Technology' (OODT). Processing is carried out in parallel across a high-powered computing cluster. The pipelines use input data from satellites such as MODIS, VIIRS and Landsat. They apply algorithms to the input data to produce a variety of outputs in GeoTIFF format. These outputs include daily data for SCAG (Snow Cover And Grain size) and DRFS (Dust Radiative Forcing in Snow), along with 8-day composites and MODICE annual minimum snow and ice calculations. This poster will describe the Snow Data System, its outputs and their uses and applications. It will also highlight recent advancements to the system and plans for the future.

Improving competitiveness through performance-measurement systems.

PubMed

Stewart, L J; Lockamy, A

2001-12-01

Parallels exist between the competitive pressures felt by U.S. manufacturers over the past 30 years and those experienced by healthcare providers today. Increasing market deregulation, changing government policies, and growing consumerism have altered the healthcare arena. Responding to similar pressures, manufacturers adopted a strategic orientation driven by customer needs and expectations that led them to achieve high performance levels and surpass their competition. The adoption of integrated performance-measurement systems was instrumental in these firms' success. An integrated performance-measurement model for healthcare organizations can help to blend the organization's strategy with the demands of the contemporary healthcare environment. Performance-measurement systems encourage healthcare organizations to focus on their mission and vision by aligning their strategic objectives and resource-allocation decisions with customer requirements.

Distributed run of a one-dimensional model in a regional application using SOAP-based web services

NASA Astrophysics Data System (ADS)

Smiatek, Gerhard

This article describes the setup of a distributed computing system in Perl. It facilitates the parallel run of a one-dimensional environmental model on a number of simple network PC hosts. The system uses Simple Object Access Protocol (SOAP) driven web services offering the model run on remote hosts and a multi-thread environment distributing the work and accessing the web services. Its application is demonstrated in a regional run of a process-oriented biogenic emission model for the area of Germany. Within a network consisting of up to seven web services implemented on Linux and MS-Windows hosts, a performance increase of approximately 400% has been reached compared to a model run on the fastest single host.

Flux pinning forces in irradiated a-axis oriented EuBa{sub 2}Cu{sub 3}O{sub 7} films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, J. I.; Gonzalez, E. M.; Kwok, W.-K

1999-10-12

{alpha}-axis oriented EuBa{sub 2}Cu{sub 3}O{sub 7} films have been irradiated with high energy heavy ions in different configurations to study the possible pinning role of the artificial defects in this kind of samples. The original pinning limiting mechanism of the samples is not essentially altered what the irradiation is parallel to the CuO{sub 2} planes. However, when it is deviated from this direction, an increase in critical current density and a change in pinning force are observed when the magnetic field is parallel to the columnar defects at values around the matching field.

Liquid-Vapor Interfacial Properties of Aqueous Solutions of Guanidinium and Methyl Guanidinium Chloride: Influence of Molecular Orientation on Interface Fluctuations

PubMed Central

Ou, Shuching; Cui, Di; Patel, Sandeep

2014-01-01

The guanidinium cation (C(NH2)3+) is a highly stable cation in aqueous solution due to its efficient solvation by water molecules and resonance stabilization of the charge. Its salts increase the solubility of nonpolar molecules (”salting-in”) and decrease the ordering of water. It is one of the strongest denaturants used in biophysical studies of protein folding. We investigate the behavior of guanidinium and its derivative, methyl guanidinium (an amino acid analogue) at the air-water surface, using atomistic molecular dynamics (MD) simulations and calculation of potentials of mean force. Methyl guanidinium cation is less excluded from the air-water surface than guanidinium cation, but both cations show orientational dependence of surface affinity. Parallel orientations of the guanidinium ring (relative to the Gibbs dividing surface) show pronounced free energy minima in the interfacial region, while ring orientations perpendicular to the GDS exhibit no discernible surface stability. Calculations of surface fluctuations demonstrate that near the air-water surface, the parallel-oriented cations generate significantly greater interfacial fluctuations compared to other orientations, which induces more long-ranged perturbations and solvent density redistribution. Our results suggest a strong correlation with induced interfacial fluctuations and ion surface stability. These results have implications for interpreting molecular-level, mechanistic action of this osmolyte’s interaction with hydrophobic interfaces as they impact protein denaturation (solubilization). PMID:23937431

Processing of Natural Echolocation Sequences in the Inferior Colliculus of Seba’s Fruit Eating Bat, Carollia perspicillata

PubMed Central

Kordes, Sebastian; Kössl, Manfred

2017-01-01

Abstract For the purpose of orientation, echolocating bats emit highly repetitive and spatially directed sonar calls. Echoes arising from call reflections are used to create an acoustic image of the environment. The inferior colliculus (IC) represents an important auditory stage for initial processing of echolocation signals. The present study addresses the following questions: (1) how does the temporal context of an echolocation sequence mimicking an approach flight of an animal affect neuronal processing of distance information to echo delays? (2) how does the IC process complex echolocation sequences containing echo information from multiple objects (multiobject sequence)? Here, we conducted neurophysiological recordings from the IC of ketamine-anaesthetized bats of the species Carollia perspicillata and compared the results from the IC with the ones from the auditory cortex (AC). Neuronal responses to an echolocation sequence was suppressed when compared to the responses to temporally isolated and randomized segments of the sequence. The neuronal suppression was weaker in the IC than in the AC. In contrast to the cortex, the time course of the acoustic events is reflected by IC activity. In the IC, suppression sharpens the neuronal tuning to specific call-echo elements and increases the signal-to-noise ratio in the units’ responses. When presenting multiple-object sequences, despite collicular suppression, the neurons responded to each object-specific echo. The latter allows parallel processing of multiple echolocation streams at the IC level. Altogether, our data suggests that temporally-precise neuronal responses in the IC could allow fast and parallel processing of multiple acoustic streams. PMID:29242823

Processing of Natural Echolocation Sequences in the Inferior Colliculus of Seba's Fruit Eating Bat, Carollia perspicillata.

PubMed

Beetz, M Jerome; Kordes, Sebastian; García-Rosales, Francisco; Kössl, Manfred; Hechavarría, Julio C

2017-01-01

For the purpose of orientation, echolocating bats emit highly repetitive and spatially directed sonar calls. Echoes arising from call reflections are used to create an acoustic image of the environment. The inferior colliculus (IC) represents an important auditory stage for initial processing of echolocation signals. The present study addresses the following questions: (1) how does the temporal context of an echolocation sequence mimicking an approach flight of an animal affect neuronal processing of distance information to echo delays? (2) how does the IC process complex echolocation sequences containing echo information from multiple objects (multiobject sequence)? Here, we conducted neurophysiological recordings from the IC of ketamine-anaesthetized bats of the species Carollia perspicillata and compared the results from the IC with the ones from the auditory cortex (AC). Neuronal responses to an echolocation sequence was suppressed when compared to the responses to temporally isolated and randomized segments of the sequence. The neuronal suppression was weaker in the IC than in the AC. In contrast to the cortex, the time course of the acoustic events is reflected by IC activity. In the IC, suppression sharpens the neuronal tuning to specific call-echo elements and increases the signal-to-noise ratio in the units' responses. When presenting multiple-object sequences, despite collicular suppression, the neurons responded to each object-specific echo. The latter allows parallel processing of multiple echolocation streams at the IC level. Altogether, our data suggests that temporally-precise neuronal responses in the IC could allow fast and parallel processing of multiple acoustic streams.

Object-oriented requirements analysis: A quick tour

NASA Technical Reports Server (NTRS)

Berard, Edward V.

1990-01-01

Of all the approaches to software development, an object-oriented approach appears to be both the most beneficial and the most popular. The description of the object-oriented approach is presented in the form of the view graphs.

Quantification of resolution in multiplanar reconstructions for digital breast tomosynthesis

NASA Astrophysics Data System (ADS)

Vent, Trevor L.; Acciavatti, Raymond J.; Kwon, Young Joon; Maidment, Andrew D. A.

2016-03-01

Multiplanar reconstruction (MPR) in digital breast tomosynthesis (DBT) allows tomographic images to be portrayed in various orientations. We have conducted research to determine the resolution of tomosynthesis MPR. We built a phantom that houses a star test pattern to measure resolution. This phantom provides three rotational degrees of freedom. The design consists of two hemispheres with longitudinal and latitudinal grooves that reference angular increments. When joined together, the hemispheres form a dome that sits inside a cylindrical encasement. The cylindrical encasement contains reference notches to match the longitudinal and latitudinal grooves that guide the phantom's rotations. With this design, any orientation of the star-pattern can be analyzed. Images of the star-pattern were acquired using a DBT mammography system at the Hospital of the University of Pennsylvania. Images taken were reconstructed and analyzed by two different methods. First, the maximum visible frequency (in line pairs per millimeter) of the star test pattern was measured. Then, the contrast was calculated at a fixed spatial frequency. These analyses confirm that resolution decreases with tilt relative to the breast support. They also confirm that resolution in tomosynthesis MPR is dependent on object orientation. Current results verify that the existence of super-resolution depends on the orientation of the frequency; the direction parallel to x-ray tube motion shows super-resolution. In conclusion, this study demonstrates that the direction of the spatial frequency relative to the motion of the x-ray tube is a determinant of resolution in MPR for DBT.

A Primer on Building Teacher Evaluation Instruments.

ERIC Educational Resources Information Center

Bitner, Ted; Kratzner, Ron

This paper presents a primer on building a scientifically oriented teacher evaluation instrument. It stresses the importance of accurate measures and accepts the presupposition that scientific approaches provide the most accurate measures of student teacher performance. The paper discusses the scientific concepts of validity and reliability, and…

Ensuring Sustainable Data Interoperability Across the Natural and Social Sciences

NASA Astrophysics Data System (ADS)

Downs, R. R.; Chen, R. S.

2015-12-01

Both the natural and social science data communities are attempting to address the long-term sustainability of their data infrastructures in rapidly changing research, technological, and policy environments. Many parts of these communities are also considering how to improve the interoperability and integration of their data and systems across natural, social, health, and other domains. However, these efforts have generally been undertaken in parallel, with little thought about how different sustainability approaches may impact long-term interoperability from scientific, legal, or economic perspectives, or vice versa, i.e., how improved interoperability could enhance—or threaten—infrastructure sustainability. Scientific progress depends substantially on the ability to learn from the legacy of previous work available for current and future scientists to study, often by integrating disparate data not previously assembled. Digital data are less likely than scientific publications to be usable in the future unless they are managed by science-oriented repositories that can support long-term data access with the documentation and services needed for future interoperability. We summarize recent discussions in the social and natural science communities on emerging approaches to sustainability and relevant interoperability activities, including efforts by the Belmont Forum E-Infrastructures project to address global change data infrastructure needs; the Group on Earth Observations to further implement data sharing and improve data management across diverse societal benefit areas; and the Research Data Alliance to develop legal interoperability principles and guidelines and to address challenges faced by domain repositories. We also examine emerging needs for data interoperability in the context of the post-2015 development agenda and the expected set of Sustainable Development Goals (SDGs), which set ambitious targets for sustainable development, poverty reduction, and environmental stewardship by 2030. These efforts suggest the need for a holistic approach towards improving and implementing strategies, policies, and practices that will ensure long-term sustainability and interoperability of scientific data repositories and networks across multiple scientific domains.

A case of complex regional pain syndrome with agnosia for object orientation.

PubMed

Robinson, Gail; Cohen, Helen; Goebel, Andreas

2011-07-01

This systematic investigation of the neurocognitive correlates of complex regional pain syndrome (CRPS) in a single case also reports agnosia for object orientation in the context of persistent CRPS. We report a patient (JW) with severe long-standing CRPS who had no difficulty identifying and naming line drawings of objects presented in 1 of 4 cardinal orientations. In contrast, he was extremely poor at reorienting these objects into the correct upright orientation and in judging whether an object was upright or not. Moreover, JW made orientation errors when copying drawings of objects, and he also showed features of mirror reversal in writing single words and reading single letters. The findings are discussed in relation to accounts of visual processing. Agnosia for object orientation is the term for impaired knowledge of an object's orientation despite good recognition and naming of the same misoriented object. This defect has previously only been reported in patients with major structural brain lesions. The neuroanatomical correlates are discussed. The patient had no structural brain lesion, raising the possibility that nonstructural reorganisation of cortical networks may be responsible for his deficits. Other patients with CRPS may have related neurocognitive defects. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Orientation priming of grasping decision for drawings of objects and blocks, and words.

PubMed

Chainay, Hanna; Naouri, Lucie; Pavec, Alice

2011-05-01

This study tested the influence of orientation priming on grasping decisions. Two groups of 20 healthy participants had to select a preferred grasping orientation (horizontal, vertical) based on drawings of everyday objects, geometric blocks or object names. Three priming conditions were used: congruent, incongruent and neutral. The facilitating effects of priming were observed in the grasping decision task for drawings of objects and blocks but not object names. The visual information about congruent orientation in the prime quickened participants' responses but had no effect on response accuracy. The results are discussed in the context of the hypothesis that an object automatically potentiates grasping associated with it, and that the on-line visual information is necessary for grasping potentiation to occur. The possibility that the most frequent orientation of familiar objects might be included in object-action representation is also discussed.

Improvement of resolution in full-view linear-array photoacoustic computed tomography using a novel adaptive weighting method

NASA Astrophysics Data System (ADS)

Omidi, Parsa; Diop, Mamadou; Carson, Jeffrey; Nasiriavanaki, Mohammadreza

2017-03-01

Linear-array-based photoacoustic computed tomography is a popular methodology for deep and high resolution imaging. However, issues such as phase aberration, side-lobe effects, and propagation limitations deteriorate the resolution. The effect of phase aberration due to acoustic attenuation and constant assumption of the speed of sound (SoS) can be reduced by applying an adaptive weighting method such as the coherence factor (CF). Utilizing an adaptive beamforming algorithm such as the minimum variance (MV) can improve the resolution at the focal point by eliminating the side-lobes. Moreover, invisibility of directional objects emitting parallel to the detection plane, such as vessels and other absorbing structures stretched in the direction perpendicular to the detection plane can degrade resolution. In this study, we propose a full-view array level weighting algorithm in which different weighs are assigned to different positions of the linear array based on an orientation algorithm which uses the histogram of oriented gradient (HOG). Simulation results obtained from a synthetic phantom show the superior performance of the proposed method over the existing reconstruction methods.

Parallel Computation of the Regional Ocean Modeling System (ROMS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, P; Song, Y T; Chao, Y

2005-04-05

The Regional Ocean Modeling System (ROMS) is a regional ocean general circulation modeling system solving the free surface, hydrostatic, primitive equations over varying topography. It is free software distributed world-wide for studying both complex coastal ocean problems and the basin-to-global scale ocean circulation. The original ROMS code could only be run on shared-memory systems. With the increasing need to simulate larger model domains with finer resolutions and on a variety of computer platforms, there is a need in the ocean-modeling community to have a ROMS code that can be run on any parallel computer ranging from 10 to hundreds ofmore » processors. Recently, we have explored parallelization for ROMS using the MPI programming model. In this paper, an efficient parallelization strategy for such a large-scale scientific software package, based on an existing shared-memory computing model, is presented. In addition, scientific applications and data-performance issues on a couple of SGI systems, including Columbia, the world's third-fastest supercomputer, are discussed.« less

Expediting Scientific Data Analysis with Reorganization of Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Byna, Surendra; Wu, Kesheng

2013-08-19

Data producers typically optimize the layout of data files to minimize the write time. In most cases, data analysis tasks read these files in access patterns different from the write patterns causing poor read performance. In this paper, we introduce Scientific Data Services (SDS), a framework for bridging the performance gap between writing and reading scientific data. SDS reorganizes data to match the read patterns of analysis tasks and enables transparent data reads from the reorganized data. We implemented a HDF5 Virtual Object Layer (VOL) plugin to redirect the HDF5 dataset read calls to the reorganized data. To demonstrate themore » effectiveness of SDS, we applied two parallel data organization techniques: a sort-based organization on a plasma physics data and a transpose-based organization on mass spectrometry imaging data. We also extended the HDF5 data access API to allow selection of data based on their values through a query interface, called SDS Query. We evaluated the execution time in accessing various subsets of data through existing HDF5 Read API and SDS Query. We showed that reading the reorganized data using SDS is up to 55X faster than reading the original data.« less

Scout: high-performance heterogeneous computing made simple

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jablin, James; Mc Cormick, Patrick; Herlihy, Maurice

2011-01-26

Researchers must often write their own simulation and analysis software. During this process they simultaneously confront both computational and scientific problems. Current strategies for aiding the generation of performance-oriented programs do not abstract the software development from the science. Furthermore, the problem is becoming increasingly complex and pressing with the continued development of many-core and heterogeneous (CPU-GPU) architectures. To acbieve high performance, scientists must expertly navigate both software and hardware. Co-design between computer scientists and research scientists can alleviate but not solve this problem. The science community requires better tools for developing, optimizing, and future-proofing codes, allowing scientists to focusmore » on their research while still achieving high computational performance. Scout is a parallel programming language and extensible compiler framework targeting heterogeneous architectures. It provides the abstraction required to buffer scientists from the constantly-shifting details of hardware while still realizing higb-performance by encapsulating software and hardware optimization within a compiler framework.« less

Parallel Processing of Objects in a Naming Task

ERIC Educational Resources Information Center

Meyer, Antje S.; Ouellet, Marc; Hacker, Christine

2008-01-01

The authors investigated whether speakers who named several objects processed them sequentially or in parallel. Speakers named object triplets, arranged in a triangle, in the order left, right, and bottom object. The left object was easy or difficult to identify and name. During the saccade from the left to the right object, the right object shown…

Object-Oriented Programming When Developing Software in Geology and Geophysics

NASA Astrophysics Data System (ADS)

Ahmadulin, R. K.; Bakanovskaya, L. N.

2017-01-01

The paper reviews the role of object-oriented programming when developing software in geology and geophysics. Main stages have been identified at which it is worthwhile to apply principles of object-oriented programming when developing software in geology and geophysics. The research was based on a number of problems solved in Geology and Petroleum Production Institute. Distinctive features of these problems are given and areas of application of the object-oriented approach are identified. Developing applications in the sphere of geology and geophysics has shown that the process of creating such products is simplified due to the use of object-oriented programming, firstly when designing structures for data storage and graphical user interfaces.

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis version 6.0 theory manual

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a theoretical manual for selected algorithms implemented within the Dakota software. It is not intended as a comprehensive theoretical treatment, since a number of existing texts cover general optimization theory, statistical analysis, and other introductory topics. Rather, this manual is intended to summarize a set of Dakota-related research publications in the areas of surrogate-based optimization, uncertainty quanti cation, and optimization under uncertainty that provide the foundation for many of Dakota's iterative analysis capabilities.« less

Modification of the anisotropy and strength differential effect of extruded AZ31 by extrusion-shear

NASA Astrophysics Data System (ADS)

Jaehnke, M.; Gensch, F.; Mueller, S.

2018-05-01

The extrusion of magnesium alloys results in a pronounced fiber texture in which the basal planes are mostly oriented parallel and the c-axes are oriented perpendicular to the extrusion direction. Due to this texture the Strength Differential Effect (SDE), which describes the strength difference between tensile and compression yield strength, and the elastic anisotropy in the sheet plane are obtained during extrusion. The objective of the investigation was to decrease the SDE and anisotropy through specifically influencing the microstructure and texture. To accomplish this objective, the forming processes extrusion (EX) and equal channel angular pressing (ECAP) were combined and integrated into one extrusion die. This combination is called extrusion-shear (ES). With an ES-die, billets of the magnesium alloy AZ31B were formed into a sheet with the thickness of 4 mm and the width of 70 mm. The angles of the used ECAP-applications in the ES-dies were set to 90° and 135°. The results show that the extrusion-shear process is able to decrease the anisotropy and SDE through transformation of the texture compared to conventional extrusion process. Also grain refinement could be observed. However, the outcomes seem to be very sensitive to the process parameters. Only by using the ES-die with an angle of 135° the desired effect could be accomplished.

PRELIMINARY COUPLING OF THE MONTE CARLO CODE OPENMC AND THE MULTIPHYSICS OBJECT-ORIENTED SIMULATION ENVIRONMENT (MOOSE) FOR ANALYZING DOPPLER FEEDBACK IN MONTE CARLO SIMULATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthew Ellis; Derek Gaston; Benoit Forget

In recent years the use of Monte Carlo methods for modeling reactors has become feasible due to the increasing availability of massively parallel computer systems. One of the primary challenges yet to be fully resolved, however, is the efficient and accurate inclusion of multiphysics feedback in Monte Carlo simulations. The research in this paper presents a preliminary coupling of the open source Monte Carlo code OpenMC with the open source Multiphysics Object-Oriented Simulation Environment (MOOSE). The coupling of OpenMC and MOOSE will be used to investigate efficient and accurate numerical methods needed to include multiphysics feedback in Monte Carlo codes.more » An investigation into the sensitivity of Doppler feedback to fuel temperature approximations using a two dimensional 17x17 PWR fuel assembly is presented in this paper. The results show a functioning multiphysics coupling between OpenMC and MOOSE. The coupling utilizes Functional Expansion Tallies to accurately and efficiently transfer pin power distributions tallied in OpenMC to unstructured finite element meshes used in MOOSE. The two dimensional PWR fuel assembly case also demonstrates that for a simplified model the pin-by-pin doppler feedback can be adequately replicated by scaling a representative pin based on pin relative powers.« less

SU-E-T-133: Dosimetric Impact of Scan Orientation Relative to Target Motion During Spot Scanning Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoker, J; Summers, P; Li, X

2014-06-01

Purpose: This study seeks to evaluate the dosimetric effects of intra-fraction motion during spot scanning proton beam therapy as a function of beam-scan orientation and target motion amplitude. Method: Multiple 4DCT scans were collected of a dynamic anthropomorphic phantom mimicking respiration amplitudes of 0 (static), 0.5, 1.0, and 1.5 cm. A spot-scanning treatment plan was developed on the maximum intensity projection image set, using an inverse-planning approach. Dynamic phantom motion was continuous throughout treatment plan delivery.The target nodule was designed to accommodate film and thermoluminescent dosimeters (TLD). Film and TLDs were uniquely labeled by location within the target. The phantommore » was localized on the treatment table using the clinically available orthogonal kV on-board imaging device. Film inserts provided data for dose uniformity; TLDs provided a 3% precision estimate of absolute dose. An inhouse script was developed to modify the delivery order of the beam spots, to orient the scanning direction parallel or perpendicular to target motion.TLD detector characterization and analysis was performed by the Imaging and Radiation Oncology Core group (IROC)-Houston. Film inserts, exhibiting a spatial resolution of 1mm, were analyzed to determine dose homogeneity within the radiation target. Results: Parallel scanning and target motions exhibited reduced target dose heterogeneity, relative to perpendicular scanning orientation. The average percent deviation in absolute dose for the motion deliveries relative to the static delivery was 4.9±1.1% for parallel scanning, and 11.7±3.5% (p<<0.05) for perpendicularly oriented scanning. Individual delivery dose deviations were not necessarily correlated to amplitude of motion for either scan orientation. Conclusions: Results demonstrate a quantifiable difference in dose heterogeneity as a function of scan orientation, more so than target amplitude. Comparison to the analyzed planar dose of a single field hint that multiple-field delivery alters intra-fraction beam-target motion synchronization and may mitigate heterogeneity, though further study is warranted.« less

Female and Male Adolescents' Subjective Orientations to Mathematics and the Influence of Those Orientations on Postsecondary Majors

ERIC Educational Resources Information Center

Perez-Felkner, Lara; McDonald, Sarah-Kathryn; Schneider, Barbara; Grogan, Erin

2012-01-01

Although important strides toward gender parity have been made in several scientific fields, women remain underrepresented in the physical sciences, engineering, mathematics, and computer sciences (PEMCs). This study examines the effects of adolescents' subjective orientations, course taking, and academic performance on the likelihood of majoring…

Checking an integrated model of web accessibility and usability evaluation for disabled people.

PubMed

Federici, Stefano; Micangeli, Andrea; Ruspantini, Irene; Borgianni, Stefano; Corradi, Fabrizio; Pasqualotto, Emanuele; Olivetti Belardinelli, Marta

2005-07-08

A combined objective-oriented and subjective-oriented method for evaluating accessibility and usability of web pages for students with disability was tested. The objective-oriented approach is devoted to verifying the conformity of interfaces to standard rules stated by national and international organizations responsible for web technology standardization, such as W3C. Conversely, the subjective-oriented approach allows assessing how the final users interact with the artificial system, accessing levels of user satisfaction based on personal factors and environmental barriers. Five kinds of measurements were applied as objective-oriented and subjective-oriented tests. Objective-oriented evaluations were performed on the Help Desk web page for students with disability, included in the website of a large Italian state university. Subjective-oriented tests were administered to 19 students labeled as disabled on the basis of their own declaration at the University enrolment: 13 students were tested by means of the SUMI test and six students by means of the 'Cooperative evaluation'. Objective-oriented and subjective-oriented methods highlighted different and sometimes conflicting results. Both methods have pointed out much more consistency regarding levels of accessibility than of usability. Since usability is largely affected by individual differences in user's own (dis)abilities, subjective-oriented measures underscored the fact that blind students encountered much more web surfing difficulties.

Molecular dynamics simulations of collagen adsorption onto grooved rutile surface: the effects of groove width.

PubMed

Chen, Mingjun; Zheng, Ting; Wu, Chunya; Xing, Cheng

2014-09-01

The early adsorption stages of collagen onto nano-grooved rutile surface without hydroxylation were studied using molecular dynamics and steered MD simulations. On the basis of plane rutile (110), two kinds of models have been adopted: single groove and parallel grooves along [1-11] crystal orientation with various width dimensions. Initially, collagens were parallel or perpendicular to the groove orientation, respectively, in order to investigate the influence of groove width on collagen adsorption. The simulation result suggests that surface grooves could exert a strong effect on collagen adsorption: when collagen was parallel to the groove direction, adsorption was favored if the groove width matched well with the dimension of collagen. However, adsorption strength may decrease as the groove width expanded. As for the condition of collagen perpendicular to the groove orientation, collagen was difficult to bend and insert into grooves in the free adsorption procedure. But the steered MD simulation results reveal that more energy was consumed for collagen to insert into narrower grooves which may be interpreted as strong barrier for adsorption. We believe that adsorption will be favored if appropriate dimension match between dimension of collagen and the groove width was approached. Copyright © 2014 Elsevier B.V. All rights reserved.

Strain rates, stress markers and earthquake clustering (Invited)

NASA Astrophysics Data System (ADS)

Fry, B.; Gerstenberger, M.; Abercrombie, R. E.; Reyners, M.; Eberhart-Phillips, D. M.

2013-12-01

The 2010-present Canterbury earthquakes comprise a well-recorded sequence in a relatively low strain-rate shallow crustal region. We present new scientific results to test the hypothesis that: Earthquake sequences in low-strain rate areas experience high stress drop events, low-post seismic relaxation, and accentuated seismic clustering. This hypothesis is based on a physical description of the aftershock process in which the spatial distribution of stress accumulation and stress transfer are controlled by fault strength and orientation. Following large crustal earthquakes, time dependent forecasts are often developed by fitting parameters defined by Omori's aftershock decay law. In high-strain rate areas, simple forecast models utilizing a single p-value fit observed aftershock sequences well. In low-strain rate areas such as Canterbury, assumptions of simple Omori decay may not be sufficient to capture the clustering (sub-sequence) nature exhibited by the punctuated rise in activity following significant child events. In Canterbury, the moment release is more clustered than in more typical Omori sequences. The individual earthquakes in these clusters also exhibit somewhat higher stress drops than in the average crustal sequence in high-strain rate regions, suggesting the earthquakes occur on strong Andersonian-oriented faults, possibly juvenile or well-healed . We use the spectral ratio procedure outlined in (Viegas et al., 2010) to determine corner frequencies and Madariaga stress-drop values for over 800 events in the sequence. Furthermore, we will discuss the relevance of tomographic results of Reyners and Eberhart-Phillips (2013) documenting post-seismic stress-driven fluid processes following the three largest events in the sequence as well as anisotropic patterns in surface wave tomography (Fry et al., 2013). These tomographic studies are both compatible with the hypothesis, providing strong evidence for the presence of widespread and hydrated regional upper crustal cracking parallel to sub-parallel to the dominant transverse failure plane in the sequence. Joint interpretation of the three separate datasets provide a positive first attempt at testing our fundamental hypothesis.

Elastic anisotropy and borehole stress estimation in the Seve Nappe Complex from the COSC-1 well, Åre, Sweden.

NASA Astrophysics Data System (ADS)

Wenning, Quinn; Almquist, Bjarne; Ask, Maria; Schmitt, Douglas R.; Zappone, Alba

2015-04-01

The Caledonian orogeny, preserved in Scandinavia and Greenland, began with the closure of the Iapetus Ocean and culminated in the collision of Baltica and Laurentia cratons during the middle Paleozoic. The COSC scientific drilling project aims at understanding the crustal structure and composition of the Scandinavian Caledonides. The first well of the dual phase drilling program, completed in Summer of 2014, drilled through ~2.5 km of the Seve Nappe Complex near the town of Åre, Sweden. Newly acquired drill core and borehole logs provide fresh core material for physical rock property measurements and in-situ stress determination. This contribution presents preliminary data on compressional and shear wave ultrasonic velocities (Vp, Vs) determined from laboratory measurements on drill cores, together with in-situ stress orientation analysis using image logs from the first borehole of the Collisional Orogeny in the Scandinavian Caledonides project (COSC-1). An hydrostatically oil pressurized apparatus is used to test the ultrasonic Vp and Vs on three orthogonally cut samples of amphibolite, calcium bearing and felsic gneiss, meta-gabbro, and mylonitic schist from drill core. We measure directional anisotropy variability for each lithology using one sample cut perpendicular to the foliation and two additional plugs cut parallel to the foliation with one parallel to the lineation and the other perpendicular. Measurements are performed using the pulse transmission technique on samples subjected to hydrostatic pressure from 1-350 MPa at dry conditions. We present preliminary results relating Vp and Vs anisotropy to geologic units and degree of deformation. Additionally, we use acoustic borehole televiewer logs to estimate the horizontal stress orientation making use of well developed techniques for observed borehole breakouts (compressive failure) and drilling induced fractures (tensile failure). Preliminary observations show that very few drilling-induced tensile fractures are produced, and that borehole breakouts are episodic and suggests a NE-SW minimum horizontal stress direction

The Assignment of Scale to Object-Oriented Software Measures

NASA Technical Reports Server (NTRS)

Neal, Ralph D.; Weistroffer, H. Roland; Coppins, Richard J.

1997-01-01

In order to improve productivity (and quality), measurement of specific aspects of software has become imperative. As object oriented programming languages have become more widely used, metrics designed specifically for object-oriented software are required. Recently a large number of new metrics for object- oriented software has appeared in the literature. Unfortunately, many of these proposed metrics have not been validated to measure what they purport to measure. In this paper fifty (50) of these metrics are analyzed.

File-System Workload on a Scientific Multiprocessor

NASA Technical Reports Server (NTRS)

Kotz, David; Nieuwejaar, Nils

1995-01-01

Many scientific applications have intense computational and I/O requirements. Although multiprocessors have permitted astounding increases in computational performance, the formidable I/O needs of these applications cannot be met by current multiprocessors a their I/O subsystems. To prevent I/O subsystems from forever bottlenecking multiprocessors and limiting the range of feasible applications, new I/O subsystems must be designed. The successful design of computer systems (both hardware and software) depends on a thorough understanding of their intended use. A system designer optimizes the policies and mechanisms for the cases expected to most common in the user's workload. In the case of multiprocessor file systems, however, designers have been forced to build file systems based only on speculation about how they would be used, extrapolating from file-system characterizations of general-purpose workloads on uniprocessor and distributed systems or scientific workloads on vector supercomputers (see sidebar on related work). To help these system designers, in June 1993 we began the Charisma Project, so named because the project sought to characterize 1/0 in scientific multiprocessor applications from a variety of production parallel computing platforms and sites. The Charisma project is unique in recording individual read and write requests-in live, multiprogramming, parallel workloads (rather than from selected or nonparallel applications). In this article, we present the first results from the project: a characterization of the file-system workload an iPSC/860 multiprocessor running production, parallel scientific applications at NASA's Ames Research Center.

Considerations of persistence and security in CHOICES, an object-oriented operating system

NASA Technical Reports Server (NTRS)

Campbell, Roy H.; Madany, Peter W.

1990-01-01

The current design of the CHOICES persistent object implementation is summarized, and research in progress is outlined. CHOICES is implemented as an object-oriented system, and persistent objects appear to simplify and unify many functions of the system. It is demonstrated that persistent data can be accessed through an object-oriented file system model as efficiently as by an existing optimized commercial file system. The object-oriented file system can be specialized to provide an object store for persistent objects. The problems that arise in building an efficient persistent object scheme in a 32-bit virtual address space that only uses paging are described. Despite its limitations, the solution presented allows quite large numbers of objects to be active simultaneously, and permits sharing and efficient method calls.

How can the English-language scientific literature be made more accessible to non-native speakers? Journals should allow greater use of referenced direct quotations in 'component-oriented' scientific writing.

PubMed

Charlton, Bruce G

2007-01-01

In scientific writing, although clarity and precision of language are vital to effective communication, it seems undeniable that content is more important than form. Potentially valuable knowledge should not be excluded from the scientific literature merely because the researchers lack advanced language skills. Given that global scientific literature is overwhelmingly in the English-language, this presents a problem for non-native speakers. My proposal is that scientists should be permitted to construct papers using a substantial number of direct quotations from the already-published scientific literature. Quotations would need to be explicitly referenced so that the original author and publication should be given full credit for creating such a useful and valid description. At the extreme, this might result in a paper consisting mainly of a 'mosaic' of quotations from the already existing scientific literature, which are linked and extended by relatively few sentences comprising new data or ideas. This model bears some conceptual relationship to the recent trend in computing science for component-based or component-oriented software engineering - in which new programs are constructed by reusing programme components, which may be available in libraries. A new functionality is constructed by linking-together many pre-existing chunks of software. I suggest that journal editors should, in their instructions to authors, explicitly allow this 'component-oriented' method of constructing scientific articles; and carefully describe how it can be accomplished in such a way that proper referencing is enforced, and full credit is allocated to the authors of the reused linguistic components.

Establishment of research-oriented hospital: an important way for translational medicine development in China.

PubMed

Li, Meina; Zhang, Lulu

2015-01-01

Globally, one of the major trends is the development of translational medicine. The traditional hospital structure could not meet the demands of translational medicine development any longer and to explore a novel hospital structure is imperative. Following the times, China proposed and implemented a development strategy for a first-class modern research-oriented hospital. To establish a research-oriented hospital has become an important strategy to guide the scientific development of high-quality medical institutions and to advance translational medicine development. To facilitate translational medicine by developing research-oriented hospital, the Chinese Research Hospital Association (CRHA) has been established, which provides service of medicine, talents cultivation, scientific research and clinical teaching and covers areas of theoretical research, academic exchange, translational medicine, talents training and practice guiding. On the whole, research-oriented hospital facilitated translational medicine by developing interdisciplinary platform, training core competencies in clinical and translational research, providing financial support of translational research, and hosting journals on translational medicine, etc.

USNO Scientific Colloquia - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You Navigation Tour Information USNO Scientific Colloquia Info USNO Scientific Colloquia Time and Place: Unless departure. Add additional time prior to arriving at the colloquium for issuance of a visitors badge and

Choices, Frameworks and Refinement

NASA Technical Reports Server (NTRS)

Campbell, Roy H.; Islam, Nayeem; Johnson, Ralph; Kougiouris, Panos; Madany, Peter

1991-01-01

In this paper we present a method for designing operating systems using object-oriented frameworks. A framework can be refined into subframeworks. Constraints specify the interactions between the subframeworks. We describe how we used object-oriented frameworks to design Choices, an object-oriented operating system.

The effects of instruction and hand dominance on grip-to-load force coordination in manipulation tasks.

PubMed

Jin, Xin; Uygur, Mehmet; Getchell, Nancy; Hall, Susan J; Jaric, Slobodan

2011-10-31

The force applied upon a vertically oriented hand-held object could be decomposed into two orthogonal and highly coordinated components: the grip force (GF; the component perpendicular to the hand-object contact area that provides friction) and the load force (LF; the parallel component that can move the object or support the body). The aim of this study was to investigate the underexplored effects of task instruction and hand dominance on GF-LF coordination. Sixteen right-handed subjects performed bimanual manipulation against a horizontally oriented instrumented device under different sets of instructions. The tasks involved exertion of ramp-and-hold or oscillation patterns of LF performed symmetrically with two hands, while the instructions regarding individual actions were either similar (pull with both hands) or dissimilar (pull with one hand and hold with another). The results revealed that the instruction "to pull" leads to higher indices of GF-LF coordination than the instruction "to hold", as evidenced by a lower GF-LF ratio, higher GF-LF coupling, and higher GF modulation. The only effect of hand dominance was a moderate time lag of GF relative to LF changes observed in the non-dominant hand. We conclude that the instructions could play an important role in GF-LF coordination and, therefore, they should be taken into account when exploring or routinely testing hand function. Additionally, the results suggest that the neural control of GF of the non-dominant hand could involve some feedback mechanisms. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Implementation of a parallel unstructured Euler solver on the CM-5

NASA Technical Reports Server (NTRS)

Morano, Eric; Mavriplis, D. J.

1995-01-01

An efficient unstructured 3D Euler solver is parallelized on a Thinking Machine Corporation Connection Machine 5, distributed memory computer with vectoring capability. In this paper, the single instruction multiple data (SIMD) strategy is employed through the use of the CM Fortran language and the CMSSL scientific library. The performance of the CMSSL mesh partitioner is evaluated and the overall efficiency of the parallel flow solver is discussed.

PISCES: An environment for parallel scientific computation

NASA Technical Reports Server (NTRS)

Pratt, T. W.

1985-01-01

The parallel implementation of scientific computing environment (PISCES) is a project to provide high-level programming environments for parallel MIMD computers. Pisces 1, the first of these environments, is a FORTRAN 77 based environment which runs under the UNIX operating system. The Pisces 1 user programs in Pisces FORTRAN, an extension of FORTRAN 77 for parallel processing. The major emphasis in the Pisces 1 design is in providing a carefully specified virtual machine that defines the run-time environment within which Pisces FORTRAN programs are executed. Each implementation then provides the same virtual machine, regardless of differences in the underlying architecture. The design is intended to be portable to a variety of architectures. Currently Pisces 1 is implemented on a network of Apollo workstations and on a DEC VAX uniprocessor via simulation of the task level parallelism. An implementation for the Flexible Computing Corp. FLEX/32 is under construction. An introduction to the Pisces 1 virtual computer and the FORTRAN 77 extensions is presented. An example of an algorithm for the iterative solution of a system of equations is given. The most notable features of the design are the provision for several granularities of parallelism in programs and the provision of a window mechanism for distributed access to large arrays of data.

Virtual Observatories, Data Mining, and Astroinformatics

NASA Astrophysics Data System (ADS)

Borne, Kirk

The historical, current, and future trends in knowledge discovery from data in astronomy are presented here. The story begins with a brief history of data gathering and data organization. A description of the development ofnew information science technologies for astronomical discovery is then presented. Among these are e-Science and the virtual observatory, with its data discovery, access, display, and integration protocols; astroinformatics and data mining for exploratory data analysis, information extraction, and knowledge discovery from distributed data collections; new sky surveys' databases, including rich multivariate observational parameter sets for large numbers of objects; and the emerging discipline of data-oriented astronomical research, called astroinformatics. Astroinformatics is described as the fourth paradigm of astronomical research, following the three traditional research methodologies: observation, theory, and computation/modeling. Astroinformatics research areas include machine learning, data mining, visualization, statistics, semantic science, and scientific data management.Each of these areas is now an active research discipline, with significantscience-enabling applications in astronomy. Research challenges and sample research scenarios are presented in these areas, in addition to sample algorithms for data-oriented research. These information science technologies enable scientific knowledge discovery from the increasingly large and complex data collections in astronomy. The education and training of the modern astronomy student must consequently include skill development in these areas, whose practitioners have traditionally been limited to applied mathematicians, computer scientists, and statisticians. Modern astronomical researchers must cross these traditional discipline boundaries, thereby borrowing the best of breed methodologies from multiple disciplines. In the era of large sky surveys and numerous large telescopes, the potential for astronomical discovery is equally large, and so the data-oriented research methods, algorithms, and techniques that are presented here will enable the greatest discovery potential from the ever-growing data and information resources in astronomy.

THE LIMITED EFFECT OF COINCIDENT ORIENTATION ON THE CHOICE OF INTRINSIC AXIS (.).

PubMed

Li, Jing; Su, Wei

2015-06-01

The allocentric system computes and represents general object-to-object spatial relationships to provide a spatial frame of reference other than the egocentric system. The intrinsic frame-of-reference system theory, which suggests people learn the locations of objects based upon an intrinsic axis, is important in research about the allocentric system. The purpose of the current study was to determine whether the effect of coincident orientation on the choice of intrinsic axis was limited. Two groups of participants (24 men, 24 women; M age = 24 yr., SD = 2) encoded different spatial layouts in which the objects shared the coincident orientation of 315° and 225° separately at learning perspective (0°). The response pattern of partial-scene-recognition task following learning reflected different strategies for choosing the intrinsic axis under different conditions. Under the 315° object-orientation condition, the objects' coincident orientation was as important as the symmetric axis in the choice of the intrinsic axis. However, participants were more likely to choose the symmetric axis as the intrinsic axis under the 225° object-orientation condition. The results suggest the effect of coincident orientation on the choice of intrinsic axis is limited.

Xyce Parallel Electronic Simulator Users' Guide Version 6.7.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiter, Eric R.; Aadithya, Karthik Venkatraman; Mei, Ting

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel com- puting platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one tomore » develop new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandia's needs, including some radiation- aware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase -- a message passing parallel implementation -- which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows. The information herein is subject to change without notice. Copyright c 2002-2017 Sandia Corporation. All rights reserved. Trademarks Xyce TM Electronic Simulator and Xyce TM are trademarks of Sandia Corporation. Orcad, Orcad Capture, PSpice and Probe are registered trademarks of Cadence Design Systems, Inc. Microsoft, Windows and Windows 7 are registered trademarks of Microsoft Corporation. Medici, DaVinci and Taurus are registered trademarks of Synopsys Corporation. Amtec and TecPlot are trademarks of Amtec Engineering, Inc. All other trademarks are property of their respective owners. Contacts World Wide Web http://xyce.sandia.gov https://info.sandia.gov/xyce (Sandia only) Email xyce@sandia.gov (outside Sandia) xyce-sandia@sandia.gov (Sandia only) Bug Reports (Sandia only) http://joseki-vm.sandia.gov/bugzilla http://morannon.sandia.gov/bugzilla« less

Kinesthetic perceptions of earth- and body-fixed axes.

PubMed

Darling, W G; Hondzinski, J M

1999-06-01

The major purpose of this research was to determine whether kinesthetic/proprioceptive perceptions of the earth-fixed vertical axis are more accurate than perceptions of intrinsic axes. In one experiment, accuracy of alignment of the forearm to earth-fixed vertical and head- and trunk-longitudinal axes by seven blindfolded subjects was compared in four tasks: (1) Earth-Arm--arm (humerus) orientation was manipulated by the experimenter; subjects aligned the forearm parallel to the vertical axis, which was also aligned with the head and trunk longitudinal axis; (2) Head--head, trunk, and upper-limb orientations were manipulated by the experimenter, subjects aligned the forearm parallel to the longitudinal axis of the head using only elbow flexion/extension and shoulder internal/external rotation; (3) Trunk--same as (2), except that subjects aligned the forearm parallel to the trunk-longitudinal axis; (4) Earth--same as (2), except that subjects aligned the forearm parallel to the earth-fixed vertical. Head, trunk, and gravitational axes were never parallel in tasks 2, 3, and 4 so that subjects could not simultaneously match their forearm to all three axes. The results showed that the errors for alignment of the forearm with the earth-fixed vertical were lower than for the trunk- and head-longitudinal axes. Furthermore, errors in the Earth condition were less dependent on alterations of the head and trunk orientation than in the Head and Trunk conditions. These data strongly suggest that the earth-fixed vertical is used as one axis for the kinesthetic sensory coordinate system that specifies upper-limb orientation at the perceptual level. We also examined the effects of varying gravitational torques at the elbow and shoulder on the accuracy of forearm alignment to earth-fixed axes. Adding a 450 g load to the forearm to increase gravitational torques when the forearm is not vertical did not improve the accuracy of forearm alignment with the vertical. Furthermore, adding small, variably sized loads (between which the subjects could not distinguish at the perceptual level) to the forearm just proximal to the wrist produced similar errors in aligning the forearm with the vertical and horizontal. Forearm-positioning errors were not correlated with the size of the load, as would be expected if gravitational torques affected forearm-position sense. We conclude that gravitational torques exerted about the shoulder and elbow do not make significant contributions to sensing forearm-orientation relative to earth-fixed axes when the upper-limb segments are not constrained by external supports.