Science.gov

Sample records for algorithms originally developed

  1. Algorithm development

    NASA Technical Reports Server (NTRS)

    Barth, Timothy J.; Lomax, Harvard

    1987-01-01

    The past decade has seen considerable activity in algorithm development for the Navier-Stokes equations. This has resulted in a wide variety of useful new techniques. Some examples for the numerical solution of the Navier-Stokes equations are presented, divided into two parts. One is devoted to the incompressible Navier-Stokes equations, and the other to the compressible form.

  2. The Origins of Counting Algorithms

    PubMed Central

    Cantlon, Jessica F.; Piantadosi, Steven T.; Ferrigno, Stephen; Hughes, Kelly D.; Barnard, Allison M.

    2015-01-01

    Humans’ ability to ‘count’ by verbally labeling discrete quantities is unique in animal cognition. The evolutionary origins of counting algorithms are not understood. We report that non-human primates exhibit a cognitive ability that is algorithmically and logically similar to human counting. Monkeys were given the task of choosing between two food caches. Monkeys saw one cache baited with some number of food items, one item at a time. Then, a second cache was baited with food items, one at a time. At the point when the second set approximately outnumbered the first set, monkeys spontaneously moved to choose the second set even before it was completely baited. Using a novel Bayesian analysis, we show that monkeys used an approximate counting algorithm to increment and compare quantities in sequence. This algorithm is structurally similar to formal counting in humans and thus may have been an important evolutionary precursor to human counting. PMID:25953949

  3. The origins of counting algorithms.

    PubMed

    Cantlon, Jessica F; Piantadosi, Steven T; Ferrigno, Stephen; Hughes, Kelly D; Barnard, Allison M

    2015-06-01

    Humans' ability to count by verbally labeling discrete quantities is unique in animal cognition. The evolutionary origins of counting algorithms are not understood. We report that nonhuman primates exhibit a cognitive ability that is algorithmically and logically similar to human counting. Monkeys were given the task of choosing between two food caches. First, they saw one cache baited with some number of food items, one item at a time. Then, a second cache was baited with food items, one at a time. At the point when the second set was approximately equal to the first set, the monkeys spontaneously moved to choose the second set even before that cache was completely baited. Using a novel Bayesian analysis, we show that the monkeys used an approximate counting algorithm for comparing quantities in sequence that is incremental, iterative, and condition controlled. This proto-counting algorithm is structurally similar to formal counting in humans and thus may have been an important evolutionary precursor to human counting. PMID:25953949

  4. The algorithmic origins of life

    PubMed Central

    Walker, Sara Imari; Davies, Paul C. W.

    2013-01-01

    Although it has been notoriously difficult to pin down precisely what is it that makes life so distinctive and remarkable, there is general agreement that its informational aspect is one key property, perhaps the key property. The unique informational narrative of living systems suggests that life may be characterized by context-dependent causal influences, and, in particular, that top-down (or downward) causation—where higher levels influence and constrain the dynamics of lower levels in organizational hierarchies—may be a major contributor to the hierarchal structure of living systems. Here, we propose that the emergence of life may correspond to a physical transition associated with a shift in the causal structure, where information gains direct and context-dependent causal efficacy over the matter in which it is instantiated. Such a transition may be akin to more traditional physical transitions (e.g. thermodynamic phase transitions), with the crucial distinction that determining which phase (non-life or life) a given system is in requires dynamical information and therefore can only be inferred by identifying causal architecture. We discuss some novel research directions based on this hypothesis, including potential measures of such a transition that may be amenable to laboratory study, and how the proposed mechanism corresponds to the onset of the unique mode of (algorithmic) information processing characteristic of living systems. PMID:23235265

  5. Algorithm-development activities

    NASA Technical Reports Server (NTRS)

    Carder, Kendall L.

    1994-01-01

    The task of algorithm-development activities at USF continues. The algorithm for determining chlorophyll alpha concentration, (Chl alpha) and gelbstoff absorption coefficient for SeaWiFS and MODIS-N radiance data is our current priority.

  6. Parallel algorithm development

    SciTech Connect

    Adams, T.F.

    1996-06-01

    Rapid changes in parallel computing technology are causing significant changes in the strategies being used for parallel algorithm development. One approach is simply to write computer code in a standard language like FORTRAN 77 or with the expectation that the compiler will produce executable code that will run in parallel. The alternatives are: (1) to build explicit message passing directly into the source code; or (2) to write source code without explicit reference to message passing or parallelism, but use a general communications library to provide efficient parallel execution. Application of these strategies is illustrated with examples of codes currently under development.

  7. Messy genetic algorithms: Recent developments

    SciTech Connect

    Kargupta, H.

    1996-09-01

    Messy genetic algorithms define a rare class of algorithms that realize the need for detecting appropriate relations among members of the search domain in optimization. This paper reviews earlier works in messy genetic algorithms and describes some recent developments. It also describes the gene expression messy GA (GEMGA)--an {Omicron}({Lambda}{sup {kappa}}({ell}{sup 2} + {kappa})) sample complexity algorithm for the class of order-{kappa} delineable problems (problems that can be solved by considering no higher than order-{kappa} relations) of size {ell} and alphabet size {Lambda}. Experimental results are presented to demonstrate the scalability of the GEMGA.

  8. Multisensor data fusion algorithm development

    SciTech Connect

    Yocky, D.A.; Chadwick, M.D.; Goudy, S.P.; Johnson, D.K.

    1995-12-01

    This report presents a two-year LDRD research effort into multisensor data fusion. We approached the problem by addressing the available types of data, preprocessing that data, and developing fusion algorithms using that data. The report reflects these three distinct areas. First, the possible data sets for fusion are identified. Second, automated registration techniques for imagery data are analyzed. Third, two fusion techniques are presented. The first fusion algorithm is based on the two-dimensional discrete wavelet transform. Using test images, the wavelet algorithm is compared against intensity modulation and intensity-hue-saturation image fusion algorithms that are available in commercial software. The wavelet approach outperforms the other two fusion techniques by preserving spectral/spatial information more precisely. The wavelet fusion algorithm was also applied to Landsat Thematic Mapper and SPOT panchromatic imagery data. The second algorithm is based on a linear-regression technique. We analyzed the technique using the same Landsat and SPOT data.

  9. Developing Scoring Algorithms

    Cancer.gov

    We developed scoring procedures to convert screener responses to estimates of individual dietary intake for fruits and vegetables, dairy, added sugars, whole grains, fiber, and calcium using the What We Eat in America 24-hour dietary recall data from the 2003-2006 NHANES.

  10. ALGORITHM DEVELOPMENT FOR SPATIAL OPERATORS.

    USGS Publications Warehouse

    Claire, Robert W.

    1984-01-01

    An approach is given that develops spatial operators about the basic geometric elements common to spatial data structures. In this fashion, a single set of spatial operators may be accessed by any system that reduces its operands to such basic generic representations. Algorithms based on this premise have been formulated to perform operations such as separation, overlap, and intersection. Moreover, this generic approach is well suited for algorithms that exploit concurrent properties of spatial operators. The results may provide a framework for a geometry engine to support fundamental manipulations within a geographic information system.

  11. Historical development of origins research.

    PubMed

    Lazcano, Antonio

    2010-11-01

    Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program. On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller's seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions. The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller's viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane

  12. Historical Development of Origins Research

    PubMed Central

    Lazcano, Antonio

    2010-01-01

    Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program. On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller’s seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions. The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller’s viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane

  13. Historical development of origins research.

    PubMed

    Lazcano, Antonio

    2010-11-01

    Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program. On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller's seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions. The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller's viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane

  14. STAR Algorithm Integration Team - Facilitating operational algorithm development

    NASA Astrophysics Data System (ADS)

    Mikles, V. J.

    2015-12-01

    The NOAA/NESDIS Center for Satellite Research and Applications (STAR) provides technical support of the Joint Polar Satellite System (JPSS) algorithm development and integration tasks. Utilizing data from the S-NPP satellite, JPSS generates over thirty Environmental Data Records (EDRs) and Intermediate Products (IPs) spanning atmospheric, ocean, cryosphere, and land weather disciplines. The Algorithm Integration Team (AIT) brings technical expertise and support to product algorithms, specifically in testing and validating science algorithms in a pre-operational environment. The AIT verifies that new and updated algorithms function in the development environment, enforces established software development standards, and ensures that delivered packages are functional and complete. AIT facilitates the development of new JPSS-1 algorithms by implementing a review approach based on the Enterprise Product Lifecycle (EPL) process. Building on relationships established during the S-NPP algorithm development process and coordinating directly with science algorithm developers, the AIT has implemented structured reviews with self-contained document suites. The process has supported algorithm improvements for products such as ozone, active fire, vegetation index, and temperature and moisture profiles.

  15. Dendrite development: a surprising origin.

    PubMed

    Ehlers, Michael D

    2005-08-15

    Neurons extend elaborate dendrites studded with spines. Unexpectedly, this cellular sculpting is regulated by the origin recognition complex -- the core machinery for initiating DNA replication. PMID:16103221

  16. Evolutionary development of path planning algorithms

    SciTech Connect

    Hage, M

    1998-09-01

    This paper describes the use of evolutionary software techniques for developing both genetic algorithms and genetic programs. Genetic algorithms are evolved to solve a specific problem within a fixed and known environment. While genetic algorithms can evolve to become very optimized for their task, they often are very specialized and perform poorly if the environment changes. Genetic programs are evolved through simultaneous training in a variety of environments to develop a more general controller behavior that operates in unknown environments. Performance of genetic programs is less optimal than a specially bred algorithm for an individual environment, but the controller performs acceptably under a wider variety of circumstances. The example problem addressed in this paper is evolutionary development of algorithms and programs for path planning in nuclear environments, such as Chernobyl.

  17. Development and Validation of a Polar Cloud Algorithm for CERES

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The objectives of this project, as described in the original proposal, were to develop an algorithm for diagnosing cloud properties over snow- and ice-covered surfaces, particularly at night, using satellite radiances from the Advanced Very High Resolution Radiometer (AVHRR) and High-resolution Infrared Radiation Sounder (HIRS) sensors. Products from this algorithm include a cloud mask and additional cloud properties such as cloud phase, amount, and height. The SIVIS software package, developed as a part of the CERES project, was originally the primary tool used to develop the algorithm, but as it is no longer supported we have had to pursue a new tool to enable the combination and analysis of collocated radiances from AVHRR and HIRS. This turned out to be a much larger endeavor than we expected, but we now have the data sets collocated (with many thanks to B. Baum for the fundamental code) and we have developed a nighttime cloud detection algorithm. Using this algorithm we have also computed realistic-looking cloud fractions from AVHRR brightness temperatures. A method to identify cloud phase has also been implemented. Atmospheric information from the TIROS Operational Vertical Sounder (TOVS) Polar Pathfinder Data Set, which includes temperature and moisture profiles as well as surface information, provides information required for determining cloud-top height.

  18. Passive microwave algorithm development and evaluation

    NASA Technical Reports Server (NTRS)

    Petty, Grant W.

    1995-01-01

    The scientific objectives of this grant are: (1) thoroughly evaluate, both theoretically and empirically, all available Special Sensor Microwave Imager (SSM/I) retrieval algorithms for column water vapor, column liquid water, and surface wind speed; (2) where both appropriate and feasible, develop, validate, and document satellite passive microwave retrieval algorithms that offer significantly improved performance compared with currently available algorithms; and (3) refine and validate a novel physical inversion scheme for retrieving rain rate over the ocean. This report summarizes work accomplished or in progress during the first year of a three year grant. The emphasis during the first year has been on the validation and refinement of the rain rate algorithm published by Petty and on the analysis of independent data sets that can be used to help evaluate the performance of rain rate algorithms over remote areas of the ocean. Two articles in the area of global oceanic precipitation are attached.

  19. Origin, development, and evolution of butterfly eyespots.

    PubMed

    Monteiro, Antónia

    2015-01-01

    This article reviews the latest developments in our understanding of the origin, development, and evolution of nymphalid butterfly eyespots. Recent contributions to this field include insights into the evolutionary and developmental origin of eyespots and their ancestral deployment on the wing, the evolution of eyespot number and eyespot sexual dimorphism, and the identification of genes affecting eyespot development and black pigmentation. I also compare features of old and more recently proposed models of eyespot development and propose a schematic for the genetic regulatory architecture of eyespots. Using this schematic I propose two hypotheses for why we observe limits to morphological diversity across these serially homologous traits.

  20. Origin, development, and evolution of butterfly eyespots.

    PubMed

    Monteiro, Antónia

    2015-01-01

    This article reviews the latest developments in our understanding of the origin, development, and evolution of nymphalid butterfly eyespots. Recent contributions to this field include insights into the evolutionary and developmental origin of eyespots and their ancestral deployment on the wing, the evolution of eyespot number and eyespot sexual dimorphism, and the identification of genes affecting eyespot development and black pigmentation. I also compare features of old and more recently proposed models of eyespot development and propose a schematic for the genetic regulatory architecture of eyespots. Using this schematic I propose two hypotheses for why we observe limits to morphological diversity across these serially homologous traits. PMID:25341098

  1. Infrared algorithm development for ocean observations

    NASA Technical Reports Server (NTRS)

    Brown, Otis B.

    1995-01-01

    Efforts continue under this contract to develop algorithms for the computation of sea surface temperature (SST) from MODIS infrared retrievals. This effort includes radiative transfer modeling, comparison of in situ and satellite observations, development and evaluation of processing and networking methodologies for algorithm computation and data accession, evaluation of surface validation approaches for IR radiances, and participation in MODIS (project) related activities. Efforts in this contract period have focused on radiative transfer modeling, evaluation of atmospheric correction methodologies, involvement in field studies, production and evaluation of new computer networking strategies, and objective analysis approaches.

  2. Progress in AMSR Snow Algorithm Development

    NASA Technical Reports Server (NTRS)

    Chang, Alfred; Koike, Toshio

    1998-01-01

    Advanced Microwave Scanning Radiometer (AMSR) will be flown on-board of the Japanese Advanced Earth Observing Satellite-II (ADEOS-II) and United States Earth Observation System (EOS) PM-1 satellite. AMSR is a passive microwave radiometer with frequency ranges from 6.9 GHz to 89 GHz. It scans conically with a constant incidence angle of 55 deg at the Earth's surface. The swath width is about 1600 km. With a large antenna, AMSR will provide the best spatial resolution of multi-frequency radiometer from space. This provides us an opportunity to improve the snow parameter retrieval. Accurate determination of snow parameters from space is a challenging effort. Over the years, many different techniques have been used to account for the complicated snow parameters such as the density, stratigraphy, snow grain size, temperature variation of the snow-pack. Forest type, fractional forest cover and land use type also need to be considered in developing an improved retrieval algorithm. However, snow is such a dynamic variable, snow-pack parameter keeps changing once the snow is deposited on the earth surface. Currently, NASDA and NASA are developing AMSR snow retrieval algorithms. These algorithms are now being carefully tested and evaluated using the SSM/I data. Due to limited snow-pack data available for comparison, this activity is progressing slowly. However, it is clear that in order to improve the snow retrieval algorithm, it is necessary to model the metamorphism history of the snow-pack.

  3. CDRD and PNPR satellite passive microwave precipitation retrieval algorithms: EuroTRMM/EURAINSAT origins and H-SAF operations

    NASA Astrophysics Data System (ADS)

    Mugnai, A.; Smith, E. A.; Tripoli, G. J.; Bizzarri, B.; Casella, D.; Dietrich, S.; Di Paola, F.; Panegrossi, G.; Sanò, P.

    2013-04-01

    including a few examples of their performance. This aspect of the development of the two algorithms is placed in the context of what we refer to as the TRMM era, which is the era denoting the active and ongoing period of the Tropical Rainfall Measuring Mission (TRMM) that helped inspire their original development. In 2015, the ISAC-Rome precipitation algorithms will undergo a transformation beginning with the upcoming Global Precipitation Measurement (GPM) mission, particularly the GPM Core Satellite technologies. A few years afterward, the first pair of imaging and sounding Meteosat Third Generation (MTG) satellites will be launched, providing additional technological advances. Various of the opportunities presented by the GPM Core and MTG satellites for improving the current CDRD and PNPR precipitation retrieval algorithms, as well as extending their product capability, are discussed.

  4. Algorithm Development Library for Environmental Satellite Missions

    NASA Astrophysics Data System (ADS)

    Smith, D. C.; Grant, K. D.; Miller, S. W.; Jamilkowski, M. L.

    2012-12-01

    science will need to migrate into the operational system. In addition, as new techniques are found to improve, supplement, or replace existing products, these changes will also require implementation into the operational system. In the past, operationalizing science algorithms and integrating them into active systems often required months of work. In order to significantly shorten the time and effort required for this activity, Raytheon has developed the Algorithm Development Library (ADL). The ADL enables scientist and researchers to develop algorithms on their own platforms, and provide these to Raytheon in a form that can be rapidly integrated directly into the operational baseline. As the JPSS CGS is a multi-mission ground system, algorithms are not restricted to Suomi NPP or JPSS missions. The ADL provides a development environment that any environmental remote sensing mission scientist can use to create algorithms that will plug into a JPSS CGS instantiation. This paper describes the ADL and how scientists and researchers can use it in their own environments.

  5. Differentiating origins of outflow tract ventricular arrhythmias: a comparison of three different electrocardiographic algorithms

    PubMed Central

    Jiao, Z.Y.; Li, Y.B.; Mao, J.; Liu, X.Y.; Yang, X.C.; Tan, C.; Chu, J.M.; Liu, X.P.

    2016-01-01

    Our objective is to evaluate the accuracy of three algorithms in differentiating the origins of outflow tract ventricular arrhythmias (OTVAs). This study involved 110 consecutive patients with OTVAs for whom a standard 12-lead surface electrocardiogram (ECG) showed typical left bundle branch block morphology with an inferior axis. All the ECG tracings were retrospectively analyzed using the following three recently published ECG algorithms: 1) the transitional zone (TZ) index, 2) the V2 transition ratio, and 3) V2 R wave duration and R/S wave amplitude indices. Considering all patients, the V2 transition ratio had the highest sensitivity (92.3%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (93.9%). The latter finding had a maximal area under the ROC curve of 0.925. In patients with left ventricular (LV) rotation, the V2 transition ratio had the highest sensitivity (94.1%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (87.5%). The former finding had a maximal area under the ROC curve of 0.892. All three published ECG algorithms are effective in differentiating the origin of OTVAs, while the V2 transition ratio, and the V2 R wave duration and R/S wave amplitude indices are the most sensitive and specific algorithms, respectively. Amongst all of the patients, the V2 R wave duration and R/S wave amplitude algorithm had the maximal area under the ROC curve, but in patients with LV rotation the V2 transition ratio algorithm had the maximum area under the ROC curve. PMID:27143173

  6. Cosmic Origins (COR) Technology Development Program Overview

    NASA Astrophysics Data System (ADS)

    Werneth, Russell; Pham, B.; Clampin, M.

    2014-01-01

    The Cosmic Origins (COR) Program Office was established in FY11 and resides at the NASA Goddard Space Flight Center (GSFC). The office serves as the implementation arm for the Astrophysics Division at NASA Headquarters for COR Program related matters. We present an overview of the Program’s technology management activities and the Program’s technology development portfolio. We discuss the process for addressing community-provided technology needs and the Technology Management Board (TMB)-vetted prioritization and investment recommendations. This process improves the transparency and relevance of technology investments, provides the community a voice in the process, and leverages the technology investments of external organizations by defining a need and a customer. Goals for the COR Program envisioned by the National Research Council’s (NRC) “New Worlds, New Horizons in Astronomy and Astrophysics” (NWNH) Decadal Survey report includes a 4m-class UV/optical telescope that would conduct imaging and spectroscopy as a post-Hubble observatory with significantly improved sensitivity and capability, a near-term investigation of NASA participation in the Japanese Aerospace Exploration Agency/Institute of Space and Astronautical Science (JAXA/ISAS) Space Infrared Telescope for Cosmology and Astrophysics (SPICA) mission, and future Explorers.

  7. Global Precipitation Measurement: GPM Microwave Imager (GMI) Algorithm Development Approach

    NASA Technical Reports Server (NTRS)

    Stocker, Erich Franz

    2009-01-01

    This slide presentation reviews the approach to the development of the Global Precipitation Measurement algorithm. This presentation includes information about the responsibilities for the development of the algorithm, and the calibration. Also included is information about the orbit, and the sun angle. The test of the algorithm code will be done with synthetic data generated from the Precipitation Processing System (PPS).

  8. Motion Cueing Algorithm Development: Initial Investigation and Redesign of the Algorithms

    NASA Technical Reports Server (NTRS)

    Telban, Robert J.; Wu, Weimin; Cardullo, Frank M.; Houck, Jacob A. (Technical Monitor)

    2000-01-01

    In this project four motion cueing algorithms were initially investigated. The classical algorithm generated results with large distortion and delay and low magnitude. The NASA adaptive algorithm proved to be well tuned with satisfactory performance, while the UTIAS adaptive algorithm produced less desirable results. Modifications were made to the adaptive algorithms to reduce the magnitude of undesirable spikes. The optimal algorithm was found to have the potential for improved performance with further redesign. The center of simulator rotation was redefined. More terms were added to the cost function to enable more tuning flexibility. A new design approach using a Fortran/Matlab/Simulink setup was employed. A new semicircular canals model was incorporated in the algorithm. With these changes results show the optimal algorithm has some advantages over the NASA adaptive algorithm. Two general problems observed in the initial investigation required solutions. A nonlinear gain algorithm was developed that scales the aircraft inputs by a third-order polynomial, maximizing the motion cues while remaining within the operational limits of the motion system. A braking algorithm was developed to bring the simulator to a full stop at its motion limit and later release the brake to follow the cueing algorithm output.

  9. Development of Speckle Interferometry Algorithm and System

    SciTech Connect

    Shamsir, A. A. M.; Jafri, M. Z. M.; Lim, H. S.

    2011-05-25

    Electronic speckle pattern interferometry (ESPI) method is a wholefield, non destructive measurement method widely used in the industries such as detection of defects on metal bodies, detection of defects in intergrated circuits in digital electronics components and in the preservation of priceless artwork. In this research field, this method is widely used to develop algorithms and to develop a new laboratory setup for implementing the speckle pattern interferometry. In speckle interferometry, an optically rough test surface is illuminated with an expanded laser beam creating a laser speckle pattern in the space surrounding the illuminated region. The speckle pattern is optically mixed with a second coherent light field that is either another speckle pattern or a smooth light field. This produces an interferometric speckle pattern that will be detected by sensor to count the change of the speckle pattern due to force given. In this project, an experimental setup of ESPI is proposed to analyze a stainless steel plate using 632.8 nm (red) wavelength of lights.

  10. Operational algorithm development and refinement approaches

    NASA Astrophysics Data System (ADS)

    Ardanuy, Philip E.

    2003-11-01

    Next-generation polar and geostationary systems, such as the National Polar-orbiting Operational Environmental Satellite System (NPOESS) and the Geostationary Operational Environmental Satellite (GOES)-R, will deploy new generations of electro-optical reflective and emissive capabilities. These will include low-radiometric-noise, improved spatial resolution multi-spectral and hyperspectral imagers and sounders. To achieve specified performances (e.g., measurement accuracy, precision, uncertainty, and stability), and best utilize the advanced space-borne sensing capabilities, a new generation of retrieval algorithms will be implemented. In most cases, these advanced algorithms benefit from ongoing testing and validation using heritage research mission algorithms and data [e.g., the Earth Observing System (EOS)] Moderate-resolution Imaging Spectroradiometer (MODIS) and Shuttle Ozone Limb Scattering Experiment (SOLSE)/Limb Ozone Retreival Experiment (LORE). In these instances, an algorithm's theoretical basis is not static, but rather improves with time. Once frozen, an operational algorithm can "lose ground" relative to research analogs. Cost/benefit analyses provide a basis for change management. The challenge is in reconciling and balancing the stability, and "comfort," that today"s generation of operational platforms provide (well-characterized, known, sensors and algorithms) with the greatly improved quality, opportunities, and risks, that the next generation of operational sensors and algorithms offer. By using the best practices and lessons learned from heritage/groundbreaking activities, it is possible to implement an agile process that enables change, while managing change. This approach combines a "known-risk" frozen baseline with preset completion schedules with insertion opportunities for algorithm advances as ongoing validation activities identify and repair areas of weak performance. This paper describes an objective, adaptive implementation roadmap that

  11. Assembled sequence contigs by SOAPdenova and Volvet algorithms from metagenomic short reads of a new bacterial isolate of gut origin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assembled sequence contigs by SOAPdenova and Volvet algorithms from metagenomic short reads of a new bacterial isolate of gut origin. This study included 2 submissions with a total of 9.8 million bp of assembled contigs....

  12. Connected-Health Algorithm: Development and Evaluation.

    PubMed

    Vlahu-Gjorgievska, Elena; Koceski, Saso; Kulev, Igor; Trajkovik, Vladimir

    2016-04-01

    Nowadays, there is a growing interest towards the adoption of novel ICT technologies in the field of medical monitoring and personal health care systems. This paper proposes design of a connected health algorithm inspired from social computing paradigm. The purpose of the algorithm is to give a recommendation for performing a specific activity that will improve user's health, based on his health condition and set of knowledge derived from the history of the user and users with similar attitudes to him. The algorithm could help users to have bigger confidence in choosing their physical activities that will improve their health. The proposed algorithm has been experimentally validated using real data collected from a community of 1000 active users. The results showed that the recommended physical activity, contributed towards weight loss of at least 0.5 kg, is found in the first half of the ordered list of recommendations, generated by the algorithm, with the probability > 0.6 with 1 % level of significance. PMID:26922593

  13. A Developed ESPRIT Algorithm for DOA Estimation

    NASA Astrophysics Data System (ADS)

    Fayad, Youssef; Wang, Caiyun; Cao, Qunsheng; Hafez, Alaa El-Din Sayed

    2015-05-01

    A novel algorithm for estimating direction of arrival (DOAE) for target, which aspires to contribute to increase the estimation process accuracy and decrease the calculation costs, has been carried out. It has introduced time and space multiresolution in Estimation of Signal Parameter via Rotation Invariance Techniques (ESPRIT) method (TS-ESPRIT) to realize subspace approach that decreases errors caused by the model's nonlinearity effect. The efficacy of the proposed algorithm is verified by using Monte Carlo simulation, the DOAE accuracy has evaluated by closed-form Cramér-Rao bound (CRB) which reveals that the proposed algorithm's estimated results are better than those of the normal ESPRIT methods leading to the estimator performance enhancement.

  14. Event-by-event PET image reconstruction using list-mode origin ensembles algorithm

    NASA Astrophysics Data System (ADS)

    Andreyev, Andriy

    2016-03-01

    There is a great demand for real time or event-by-event (EBE) image reconstruction in emission tomography. Ideally, as soon as event has been detected by the acquisition electronics, it needs to be used in the image reconstruction software. This would greatly speed up the image reconstruction since most of the data will be processed and reconstructed while the patient is still undergoing the scan. Unfortunately, the current industry standard is that the reconstruction of the image would not start until all the data for the current image frame would be acquired. Implementing an EBE reconstruction for MLEM family of algorithms is possible, but not straightforward as multiple (computationally expensive) updates to the image estimate are required. In this work an alternative Origin Ensembles (OE) image reconstruction algorithm for PET imaging is converted to EBE mode and is investigated whether it is viable alternative for real-time image reconstruction. In OE algorithm all acquired events are seen as points that are located somewhere along the corresponding line-of-responses (LORs), together forming a point cloud. Iteratively, with a multitude of quasi-random shifts following the likelihood function the point cloud converges to a reflection of an actual radiotracer distribution with the degree of accuracy that is similar to MLEM. New data can be naturally added into the point cloud. Preliminary results with simulated data show little difference between regular reconstruction and EBE mode, proving the feasibility of the proposed approach.

  15. Probabilistic structural analysis algorithm development for computational efficiency

    NASA Technical Reports Server (NTRS)

    Wu, Y.-T.

    1991-01-01

    The PSAM (Probabilistic Structural Analysis Methods) program is developing a probabilistic structural risk assessment capability for the SSME components. An advanced probabilistic structural analysis software system, NESSUS (Numerical Evaluation of Stochastic Structures Under Stress), is being developed as part of the PSAM effort to accurately simulate stochastic structures operating under severe random loading conditions. One of the challenges in developing the NESSUS system is the development of the probabilistic algorithms that provide both efficiency and accuracy. The main probability algorithms developed and implemented in the NESSUS system are efficient, but approximate in nature. In the last six years, the algorithms have improved very significantly.

  16. A Two-Stage Algorithm for Origin-Destination Matrices Estimation Considering Dynamic Dispersion Parameter for Route Choice

    PubMed Central

    Wang, Yong; Ma, Xiaolei; Liu, Yong; Gong, Ke; Henricakson, Kristian C.; Xu, Maozeng; Wang, Yinhai

    2016-01-01

    This paper proposes a two-stage algorithm to simultaneously estimate origin-destination (OD) matrix, link choice proportion, and dispersion parameter using partial traffic counts in a congested network. A non-linear optimization model is developed which incorporates a dynamic dispersion parameter, followed by a two-stage algorithm in which Generalized Least Squares (GLS) estimation and a Stochastic User Equilibrium (SUE) assignment model are iteratively applied until the convergence is reached. To evaluate the performance of the algorithm, the proposed approach is implemented in a hypothetical network using input data with high error, and tested under a range of variation coefficients. The root mean squared error (RMSE) of the estimated OD demand and link flows are used to evaluate the model estimation results. The results indicate that the estimated dispersion parameter theta is insensitive to the choice of variation coefficients. The proposed approach is shown to outperform two established OD estimation methods and produce parameter estimates that are close to the ground truth. In addition, the proposed approach is applied to an empirical network in Seattle, WA to validate the robustness and practicality of this methodology. In summary, this study proposes and evaluates an innovative computational approach to accurately estimate OD matrices using link-level traffic flow data, and provides useful insight for optimal parameter selection in modeling travelers’ route choice behavior. PMID:26761209

  17. A Two-Stage Algorithm for Origin-Destination Matrices Estimation Considering Dynamic Dispersion Parameter for Route Choice.

    PubMed

    Wang, Yong; Ma, Xiaolei; Liu, Yong; Gong, Ke; Henrickson, Kristian C; Henricakson, Kristian C; Xu, Maozeng; Wang, Yinhai

    2016-01-01

    This paper proposes a two-stage algorithm to simultaneously estimate origin-destination (OD) matrix, link choice proportion, and dispersion parameter using partial traffic counts in a congested network. A non-linear optimization model is developed which incorporates a dynamic dispersion parameter, followed by a two-stage algorithm in which Generalized Least Squares (GLS) estimation and a Stochastic User Equilibrium (SUE) assignment model are iteratively applied until the convergence is reached. To evaluate the performance of the algorithm, the proposed approach is implemented in a hypothetical network using input data with high error, and tested under a range of variation coefficients. The root mean squared error (RMSE) of the estimated OD demand and link flows are used to evaluate the model estimation results. The results indicate that the estimated dispersion parameter theta is insensitive to the choice of variation coefficients. The proposed approach is shown to outperform two established OD estimation methods and produce parameter estimates that are close to the ground truth. In addition, the proposed approach is applied to an empirical network in Seattle, WA to validate the robustness and practicality of this methodology. In summary, this study proposes and evaluates an innovative computational approach to accurately estimate OD matrices using link-level traffic flow data, and provides useful insight for optimal parameter selection in modeling travelers' route choice behavior. PMID:26761209

  18. Modified multiscale sample entropy computation of laser speckle contrast images and comparison with the original multiscale entropy algorithm

    NASA Astrophysics Data System (ADS)

    Humeau-Heurtier, Anne; Mahé, Guillaume; Abraham, Pierre

    2015-12-01

    Laser speckle contrast imaging (LSCI) enables a noninvasive monitoring of microvascular perfusion. Some studies have proposed to extract information from LSCI data through their multiscale entropy (MSE). However, for reaching a large range of scales, the original MSE algorithm may require long recordings for reliability. Recently, a novel approach to compute MSE with shorter data sets has been proposed: the short-time MSE (sMSE). Our goal is to apply, for the first time, the sMSE algorithm in LSCI data and to compare results with those given by the original MSE. Moreover, we apply the original MSE algorithm on data of different lengths and compare results with those given by longer recordings. For this purpose, synthetic signals and 192 LSCI regions of interest (ROIs) of different sizes are processed. Our results show that the sMSE algorithm is valid to compute the MSE of LSCI data. Moreover, with time series shorter than those initially proposed, the sMSE and original MSE algorithms give results with no statistical difference from those of the original MSE algorithm with longer data sets. The minimal acceptable length depends on the ROI size. Comparisons of MSE from healthy and pathological subjects can be performed with shorter data sets than those proposed until now.

  19. Motion Cueing Algorithm Development: Piloted Performance Testing of the Cueing Algorithms

    NASA Technical Reports Server (NTRS)

    Houck, Jacob A. (Technical Monitor); Telban, Robert J.; Cardullo, Frank M.; Kelly, Lon C.

    2005-01-01

    The relative effectiveness in simulating aircraft maneuvers with both current and newly developed motion cueing algorithms was assessed with an eleven-subject piloted performance evaluation conducted on the NASA Langley Visual Motion Simulator (VMS). In addition to the current NASA adaptive algorithm, two new cueing algorithms were evaluated: the optimal algorithm and the nonlinear algorithm. The test maneuvers included a straight-in approach with a rotating wind vector, an offset approach with severe turbulence and an on/off lateral gust that occurs as the aircraft approaches the runway threshold, and a takeoff both with and without engine failure after liftoff. The maneuvers were executed with each cueing algorithm with added visual display delay conditions ranging from zero to 200 msec. Two methods, the quasi-objective NASA Task Load Index (TLX), and power spectral density analysis of pilot control, were used to assess pilot workload. Piloted performance parameters for the approach maneuvers, the vertical velocity upon touchdown and the runway touchdown position, were also analyzed but did not show any noticeable difference among the cueing algorithms. TLX analysis reveals, in most cases, less workload and variation among pilots with the nonlinear algorithm. Control input analysis shows pilot-induced oscillations on a straight-in approach were less prevalent compared to the optimal algorithm. The augmented turbulence cues increased workload on an offset approach that the pilots deemed more realistic compared to the NASA adaptive algorithm. The takeoff with engine failure showed the least roll activity for the nonlinear algorithm, with the least rudder pedal activity for the optimal algorithm.

  20. Organization Development: Its Nature, Origins, and Prospects.

    ERIC Educational Resources Information Center

    Bennis, Warren G.

    A primer on organization development (OD), this book presents a basic statement for people in organizations and for practitioners and students of OD. Many concrete examples are included. After a definition of OD, the basic conditions which create the need for OD are discussed: rapid change, growth in size, increasing diversity, change in…

  1. [Academic origin, development and characteristic of Xujiang acupuncture school].

    PubMed

    Xie, Yufeng; Yang Zongbao; Chen, Yun; Wang, Ling; Wang, Shuhui; Yang, Lixia

    2016-03-01

    The origin time, representative physicians and medical works of Xujiang acupuncture school were traced, so as to explore the academic origin and development and summarize the academic characteristic of Xujiang acupuncture school, which could make a better inheritance of academic essence and prompt the innovation and development of Xujiang acupuncture school.

  2. [Academic origin, development and characteristic of Xujiang acupuncture school].

    PubMed

    Xie, Yufeng; Yang Zongbao; Chen, Yun; Wang, Ling; Wang, Shuhui; Yang, Lixia

    2016-03-01

    The origin time, representative physicians and medical works of Xujiang acupuncture school were traced, so as to explore the academic origin and development and summarize the academic characteristic of Xujiang acupuncture school, which could make a better inheritance of academic essence and prompt the innovation and development of Xujiang acupuncture school. PMID:27344849

  3. Origin of texture development in orthorhombic uranium

    DOE PAGES

    Zecevic, Miroslav; Knezevic, Marko; Beyerlein, Irene Jane; McCabe, Rodney James

    2016-04-09

    We study texture evolution of alpha-uranium (α-U) during plane strain compression and uniaxial compression to high strains at different temperatures. We combine a multiscale polycrystal constitutive model and detailed analysis of texture data to uncover the slip and twinning modes responsible for the formation of individual texture components. The analysis indicates that during plane strain compression, floor slip (001)[100] results in the formation of two pronounced {001}{001} texture peaks tilted 10–15° away from the normal toward the rolling direction. During both high-temperature (573 K) through-thickness compression and plane strain compression, the active slip modes are floor slip (001)[100] and chimneymore » slip 1/2{110} <11¯0> with slightly different ratios. {130} <31¯0> deformation twinning is profuse during rolling and in-plane compression and decreases with increasing temperature, but is not as active for through-thickness compression. Lastly, we comment on some similarities between rolling textures of α-U, which has a c/a ratio of 1.734, and those that develop in hexagonal close packed metals with similarly high c/a ratios like Zn (1.856) and Cd (1.885) and are dominated by basal slip.« less

  4. Advances in fracture algorithm development in GRIM

    NASA Astrophysics Data System (ADS)

    Cullis, I.; Church, P.; Greenwood, P.; Huntington-Thresher, W.; Reynolds, M.

    2003-09-01

    The numerical treatment of fracture processes has long been a major challenge in any hydrocode, but has been particularly acute in Eulerian Hydrocodes. This is due to the difficulties in establishing a consistent process for treating failure and the post failure treatment, which is complicated by advection, mixed cell and interface issues, particularly post failure. This alone increase the complexity of incorporating and validating a failure model compared to a Lagrange hydrocode, where the numerical treatment is much simpler. This paper outlines recent significant progress in the incorporation of fracture models in GRIM and the advection of damage across cell boundaries within the mesh. This has allowed a much more robust treatment of fracture in an Eulerian frame of reference and has greatly expanded the scope of tractable dynamic fracture scenarios. The progress has been possible due to a careful integration of the fracture algorithm within the numerical integration scheme to maintain a consistent representation of the physics. The paper describes various applications, which demonstrate the robustness and efficiency of the scheme and highlight some of the future challenges.

  5. Developer Tools for Evaluating Multi-Objective Algorithms

    NASA Technical Reports Server (NTRS)

    Giuliano, Mark E.; Johnston, Mark D.

    2011-01-01

    Multi-objective algorithms for scheduling offer many advantages over the more conventional single objective approach. By keeping user objectives separate instead of combined, more information is available to the end user to make trade-offs between competing objectives. Unlike single objective algorithms, which produce a single solution, multi-objective algorithms produce a set of solutions, called a Pareto surface, where no solution is strictly dominated by another solution for all objectives. From the end-user perspective a Pareto-surface provides a tool for reasoning about trade-offs between competing objectives. From the perspective of a software developer multi-objective algorithms provide an additional challenge. How can you tell if one multi-objective algorithm is better than another? This paper presents formal and visual tools for evaluating multi-objective algorithms and shows how the developer process of selecting an algorithm parallels the end-user process of selecting a solution for execution out of the Pareto-Surface.

  6. Development and Evaluation of Algorithms for Breath Alcohol Screening

    PubMed Central

    Ljungblad, Jonas; Hök, Bertil; Ekström, Mikael

    2016-01-01

    Breath alcohol screening is important for traffic safety, access control and other areas of health promotion. A family of sensor devices useful for these purposes is being developed and evaluated. This paper is focusing on algorithms for the determination of breath alcohol concentration in diluted breath samples using carbon dioxide to compensate for the dilution. The examined algorithms make use of signal averaging, weighting and personalization to reduce estimation errors. Evaluation has been performed by using data from a previously conducted human study. It is concluded that these features in combination will significantly reduce the random error compared to the signal averaging algorithm taken alone. PMID:27043576

  7. Development and Evaluation of Algorithms for Breath Alcohol Screening.

    PubMed

    Ljungblad, Jonas; Hök, Bertil; Ekström, Mikael

    2016-01-01

    Breath alcohol screening is important for traffic safety, access control and other areas of health promotion. A family of sensor devices useful for these purposes is being developed and evaluated. This paper is focusing on algorithms for the determination of breath alcohol concentration in diluted breath samples using carbon dioxide to compensate for the dilution. The examined algorithms make use of signal averaging, weighting and personalization to reduce estimation errors. Evaluation has been performed by using data from a previously conducted human study. It is concluded that these features in combination will significantly reduce the random error compared to the signal averaging algorithm taken alone. PMID:27043576

  8. Developing A Navier-Stokes Algorithm For Supercomputers

    NASA Technical Reports Server (NTRS)

    Swisshelm, Julie M.

    1992-01-01

    Report discusses development of algorithm for solution of Navier-Stokes equations of flow on parallel-processing supercomputers. Involves combination of prior techniques to form algorithm to compute flows in complicated three-dimensional configurations. Includes explicit finite-difference numerical-integration scheme applicable to flows represented by hierarchy of mathematical models ranging from Euler to full Navier-Stokes. Of interest to researchers looking for ways to structure problems for greater computational efficiency.

  9. Algorithm development for Maxwell's equations for computational electromagnetism

    NASA Technical Reports Server (NTRS)

    Goorjian, Peter M.

    1990-01-01

    A new algorithm has been developed for solving Maxwell's equations for the electromagnetic field. It solves the equations in the time domain with central, finite differences. The time advancement is performed implicitly, using an alternating direction implicit procedure. The space discretization is performed with finite volumes, using curvilinear coordinates with electromagnetic components along those directions. Sample calculations are presented of scattering from a metal pin, a square and a circle to demonstrate the capabilities of the new algorithm.

  10. Infrared Algorithm Development for Ocean Observations with EOS/MODIS

    NASA Technical Reports Server (NTRS)

    Brown, Otis B.

    1997-01-01

    Efforts continue under this contract to develop algorithms for the computation of sea surface temperature (SST) from MODIS infrared measurements. This effort includes radiative transfer modeling, comparison of in situ and satellite observations, development and evaluation of processing and networking methodologies for algorithm computation and data accession, evaluation of surface validation approaches for IR radiances, development of experimental instrumentation, and participation in MODIS (project) related activities. Activities in this contract period have focused on radiative transfer modeling, evaluation of atmospheric correction methodologies, undertake field campaigns, analysis of field data, and participation in MODIS meetings.

  11. Translanguaging: Origins and Development from School to Street and beyond

    ERIC Educational Resources Information Center

    Lewis, Gwyn; Jones, Bryn; Baker, Colin

    2012-01-01

    The article traces the Welsh origins of "translanguaging" from the 1980s to the recent global use, analysing the development and extension of the term. It suggests that the growing popularity of the term relates to a change in the way bilingualism and multilingualism have ideologically developed not only among academics but also amid changing…

  12. System development of the Screwworm Eradication Data System (SEDS) algorithm

    NASA Technical Reports Server (NTRS)

    Arp, G.; Forsberg, F.; Giddings, L.; Phinney, D.

    1976-01-01

    The use of remotely sensed data is reported in the eradication of the screwworm and in the study of the role of the weather in the activity and development of the screwworm fly. As a result, the Screwworm Eradication Data System (SEDS) algorithm was developed.

  13. Development and Testing of Data Mining Algorithms for Earth Observation

    NASA Technical Reports Server (NTRS)

    Glymour, Clark

    2005-01-01

    The new algorithms developed under this project included a principled procedure for classification of objects, events or circumstances according to a target variable when a very large number of potential predictor variables is available but the number of cases that can be used for training a classifier is relatively small. These "high dimensional" problems require finding a minimal set of variables -called the Markov Blanket-- sufficient for predicting the value of the target variable. An algorithm, the Markov Blanket Fan Search, was developed, implemented and tested on both simulated and real data in conjunction with a graphical model classifier, which was also implemented. Another algorithm developed and implemented in TETRAD IV for time series elaborated on work by C. Granger and N. Swanson, which in turn exploited some of our earlier work. The algorithms in question learn a linear time series model from data. Given such a time series, the simultaneous residual covariances, after factoring out time dependencies, may provide information about causal processes that occur more rapidly than the time series representation allow, so called simultaneous or contemporaneous causal processes. Working with A. Monetta, a graduate student from Italy, we produced the correct statistics for estimating the contemporaneous causal structure from time series data using the TETRAD IV suite of algorithms. Two economists, David Bessler and Kevin Hoover, have independently published applications using TETRAD style algorithms to the same purpose. These implementations and algorithmic developments were separately used in two kinds of studies of climate data: Short time series of geographically proximate climate variables predicting agricultural effects in California, and longer duration climate measurements of temperature teleconnections.

  14. Implementation on Landsat Data of a Simple Cloud Mask Algorithm Developed for MODIS Land Bands

    NASA Technical Reports Server (NTRS)

    Oreopoulos, Lazaros; Wilson, Michael J.; Varnai, Tamas

    2010-01-01

    This letter assesses the performance on Landsat-7 images of a modified version of a cloud masking algorithm originally developed for clear-sky compositing of Moderate Resolution Imaging Spectroradiometer (MODIS) images at northern mid-latitudes. While data from recent Landsat missions include measurements at thermal wavelengths, and such measurements are also planned for the next mission, thermal tests are not included in the suggested algorithm in its present form to maintain greater versatility and ease of use. To evaluate the masking algorithm we take advantage of the availability of manual (visual) cloud masks developed at USGS for the collection of Landsat scenes used here. As part of our evaluation we also include the Automated Cloud Cover Assesment (ACCA) algorithm that includes thermal tests and is used operationally by the Landsat-7 mission to provide scene cloud fractions, but no cloud masks. We show that the suggested algorithm can perform about as well as ACCA both in terms of scene cloud fraction and pixel-level cloud identification. Specifically, we find that the algorithm gives an error of 1.3% for the scene cloud fraction of 156 scenes, and a root mean square error of 7.2%, while it agrees with the manual mask for 93% of the pixels, figures very similar to those from ACCA (1.2%, 7.1%, 93.7%).

  15. Infrared algorithm development for ocean observations with EOS/MODIS

    NASA Technical Reports Server (NTRS)

    Brown, Otis B.

    1994-01-01

    Efforts continue under this contract to develop algorithms for the computation of sea surface temperature (SST) from MODIS infrared retrievals. This effort includes radiative transfer modeling, comparison of in situ and satellite observations, development and evaluation of processing and networking methodologies for algorithm computation and data accession, evaluation of surface validation approaches for IR radiances, and participation in MODIS (project) related activities. Efforts in this contract period have focused on radiative transfer modeling and evaluation of atmospheric path radiance efforts on SST estimation, exploration of involvement in ongoing field studies, evaluation of new computer networking strategies, and objective analysis approaches.

  16. On the development of protein pKa calculation algorithms

    SciTech Connect

    Carstensen, Tommy; Farrell, Damien; Huang, Yong; Baker, Nathan A.; Nielsen, Jens E.

    2011-12-01

    Protein pKa calculation algorithms are typically developed to reproduce experimental pKa values and provide us with a better understanding of the fundamental importance of electrostatics for protein structure and function. However, the approximations and adjustable parameters employed in almost all pKa calculation methods means that there is the risk that pKa calculation algorithms are 'over-fitted' to the available datasets, and that these methods therefore do not model protein physics realistically. We employ simulations of the protein pKa calculation algorithm development process to show that careful optimization procedures and non-biased experimental datasets must be applied to ensure a realistic description of the underlying physical terms. We furthermore investigate the effect of experimental noise and find a significant effect on the pKa calculation algorithm optimization landscape. Finally, we comment on strategies for ensuring the physical realism of protein pKa calculation algorithms and we assess the overall state of the field with a view to predicting future directions of development.

  17. Origin, Development, and Homeostasis of Tissue-resident Macrophages

    PubMed Central

    Haldar, Malay; Murphy, Kenneth M.

    2014-01-01

    Summary Macrophages are versatile cells of the hematopoietic system that display remarkable functional diversity encompassing innate immune responses, tissue development, and tissue homeostasis. Macrophages are present in almost all tissues of the body and display distinct location-specific phenotypes and gene expression profiles. Recent studies also demonstrate distinct origins of tissue-resident macrophages. This emerging picture of ontological, functional, and phenotypic heterogeneity within tissue macrophages has altered our understanding of these cells, which play important roles in many human diseases. In this review, we discuss the different origins of tissue macrophages, the transcription factors regulating their development, and the mechanisms underlying their homeostasis at steady state. PMID:25319325

  18. Development and Application of a Portable Health Algorithms Test System

    NASA Technical Reports Server (NTRS)

    Melcher, Kevin J.; Fulton, Christopher E.; Maul, William A.; Sowers, T. Shane

    2007-01-01

    This paper describes the development and initial demonstration of a Portable Health Algorithms Test (PHALT) System that is being developed by researchers at the NASA Glenn Research Center (GRC). The PHALT System was conceived as a means of evolving the maturity and credibility of algorithms developed to assess the health of aerospace systems. Comprising an integrated hardware-software environment, the PHALT System allows systems health management algorithms to be developed in a graphical programming environment; to be tested and refined using system simulation or test data playback; and finally, to be evaluated in a real-time hardware-in-the-loop mode with a live test article. In this paper, PHALT System development is described through the presentation of a functional architecture, followed by the selection and integration of hardware and software. Also described is an initial real-time hardware-in-the-loop demonstration that used sensor data qualification algorithms to diagnose and isolate simulated sensor failures in a prototype Power Distribution Unit test-bed. Success of the initial demonstration is highlighted by the correct detection of all sensor failures and the absence of any real-time constraint violations.

  19. Using Hypertext To Develop an Algorithmic Approach to Teaching Statistics.

    ERIC Educational Resources Information Center

    Halavin, James; Sommer, Charles

    Hypertext and its more advanced form Hypermedia represent a powerful authoring tool with great potential for allowing statistics teachers to develop documents to assist students in an algorithmic fashion. An introduction to the use of Hypertext is presented, with an example of its use. Hypertext is an approach to information management in which…

  20. Development, Comparisons and Evaluation of Aerosol Retrieval Algorithms

    NASA Astrophysics Data System (ADS)

    de Leeuw, G.; Holzer-Popp, T.; Aerosol-cci Team

    2011-12-01

    The Climate Change Initiative (cci) of the European Space Agency (ESA) has brought together a team of European Aerosol retrieval groups working on the development and improvement of aerosol retrieval algorithms. The goal of this cooperation is the development of methods to provide the best possible information on climate and climate change based on satellite observations. To achieve this, algorithms are characterized in detail as regards the retrieval approaches, the aerosol models used in each algorithm, cloud detection and surface treatment. A round-robin intercomparison of results from the various participating algorithms serves to identify the best modules or combinations of modules for each sensor. Annual global datasets including their uncertainties will then be produced and validated. The project builds on 9 existing algorithms to produce spectral aerosol optical depth (AOD and Ångström exponent) as well as other aerosol information; two instruments are included to provide the absorbing aerosol index (AAI) and stratospheric aerosol information. The algorithms included are: - 3 for ATSR (ORAC developed by RAL / Oxford university, ADV developed by FMI and the SU algorithm developed by Swansea University ) - 2 for MERIS (BAER by Bremen university and the ESA standard handled by HYGEOS) - 1 for POLDER over ocean (LOA) - 1 for synergetic retrieval (SYNAER by DLR ) - 1 for OMI retreival of the absorbing aerosol index with averaging kernel information (KNMI) - 1 for GOMOS stratospheric extinction profile retrieval (BIRA) The first seven algorithms aim at the retrieval of the AOD. However, each of the algorithms used differ in their approach, even for algorithms working with the same instrument such as ATSR or MERIS. To analyse the strengths and weaknesses of each algorithm several tests are made. The starting point for comparison and measurement of improvements is a retrieval run for 1 month, September 2008. The data from the same month are subsequently used for

  1. Algorithm integration using ADL (Algorithm Development Library) for improving CrIMSS EDR science product quality

    NASA Astrophysics Data System (ADS)

    Das, B.; Wilson, M.; Divakarla, M. G.; Chen, W.; Barnet, C.; Wolf, W.

    2013-05-01

    Algorithm Development Library (ADL) is a framework that mimics the operational system IDPS (Interface Data Processing Segment) that is currently being used to process data from instruments aboard Suomi National Polar-orbiting Partnership (S-NPP) satellite. The satellite was launched successfully in October 2011. The Cross-track Infrared and Microwave Sounder Suite (CrIMSS) consists of the Advanced Technology Microwave Sounder (ATMS) and Cross-track Infrared Sounder (CrIS) instruments that are on-board of S-NPP. These instruments will also be on-board of JPSS (Joint Polar Satellite System) that will be launched in early 2017. The primary products of the CrIMSS Environmental Data Record (EDR) include global atmospheric vertical temperature, moisture, and pressure profiles (AVTP, AVMP and AVPP) and Ozone IP (Intermediate Product from CrIS radiances). Several algorithm updates have recently been proposed by CrIMSS scientists that include fixes to the handling of forward modeling errors, a more conservative identification of clear scenes, indexing corrections for daytime products, and relaxed constraints between surface temperature and air temperature for daytime land scenes. We have integrated these improvements into the ADL framework. This work compares the results from ADL emulation of future IDPS system incorporating all the suggested algorithm updates with the current official processing results by qualitative and quantitative evaluations. The results prove these algorithm updates improve science product quality.

  2. Datasets for radiation network algorithm development and testing

    SciTech Connect

    Rao, Nageswara S; Sen, Satyabrata; Berry, M. L..; Wu, Qishi; Grieme, M.; Brooks, Richard R; Cordone, G.

    2016-01-01

    Domestic Nuclear Detection Office s (DNDO) Intelligence Radiation Sensors Systems (IRSS) program supported the development of networks of commercial-off-the-shelf (COTS) radiation counters for detecting, localizing, and identifying low-level radiation sources. Under this program, a series of indoor and outdoor tests were conducted with multiple source strengths and types, different background profiles, and various types of source and detector movements. Following the tests, network algorithms were replayed in various re-constructed scenarios using sub-networks. These measurements and algorithm traces together provide a rich collection of highly valuable datasets for testing the current and next generation radiation network algorithms, including the ones (to be) developed by broader R&D communities such as distributed detection, information fusion, and sensor networks. From this multiple TeraByte IRSS database, we distilled out and packaged the first batch of canonical datasets for public release. They include measurements from ten indoor and two outdoor tests which represent increasingly challenging baseline scenarios for robustly testing radiation network algorithms.

  3. Developing and Implementing the Data Mining Algorithms in RAVEN

    SciTech Connect

    Sen, Ramazan Sonat; Maljovec, Daniel Patrick; Alfonsi, Andrea; Rabiti, Cristian

    2015-09-01

    The RAVEN code is becoming a comprehensive tool to perform probabilistic risk assessment, uncertainty quantification, and verification and validation. The RAVEN code is being developed to support many programs and to provide a set of methodologies and algorithms for advanced analysis. Scientific computer codes can generate enormous amounts of data. To post-process and analyze such data might, in some cases, take longer than the initial software runtime. Data mining algorithms/methods help in recognizing and understanding patterns in the data, and thus discover knowledge in databases. The methodologies used in the dynamic probabilistic risk assessment or in uncertainty and error quantification analysis couple system/physics codes with simulation controller codes, such as RAVEN. RAVEN introduces both deterministic and stochastic elements into the simulation while the system/physics code model the dynamics deterministically. A typical analysis is performed by sampling values of a set of parameter values. A major challenge in using dynamic probabilistic risk assessment or uncertainty and error quantification analysis for a complex system is to analyze the large number of scenarios generated. Data mining techniques are typically used to better organize and understand data, i.e. recognizing patterns in the data. This report focuses on development and implementation of Application Programming Interfaces (APIs) for different data mining algorithms, and the application of these algorithms to different databases.

  4. Development of microwave rainfall retrieval algorithm for climate applications

    NASA Astrophysics Data System (ADS)

    KIM, J. H.; Shin, D. B.

    2014-12-01

    With the accumulated satellite datasets for decades, it is possible that satellite-based data could contribute to sustained climate applications. Level-3 products from microwave sensors for climate applications can be obtained from several algorithms. For examples, the Microwave Emission brightness Temperature Histogram (METH) algorithm produces level-3 rainfalls directly, whereas the Goddard profiling (GPROF) algorithm first generates instantaneous rainfalls and then temporal and spatial averaging process leads to level-3 products. The rainfall algorithm developed in this study follows a similar approach to averaging instantaneous rainfalls. However, the algorithm is designed to produce instantaneous rainfalls at an optimal resolution showing reduced non-linearity in brightness temperature (TB)-rain rate(R) relations. It is found that the resolution tends to effectively utilize emission channels whose footprints are relatively larger than those of scattering channels. This algorithm is mainly composed of a-priori databases (DBs) and a Bayesian inversion module. The DB contains massive pairs of simulated microwave TBs and rain rates, obtained by WRF (version 3.4) and RTTOV (version 11.1) simulations. To improve the accuracy and efficiency of retrieval process, data mining technique is additionally considered. The entire DB is classified into eight types based on Köppen climate classification criteria using reanalysis data. Among these sub-DBs, only one sub-DB which presents the most similar physical characteristics is selected by considering the thermodynamics of input data. When the Bayesian inversion is applied to the selected DB, instantaneous rain rate with 6 hours interval is retrieved. The retrieved monthly mean rainfalls are statistically compared with CMAP and GPCP, respectively.

  5. Oscillation Detection Algorithm Development Summary Report and Test Plan

    SciTech Connect

    Zhou, Ning; Huang, Zhenyu; Tuffner, Francis K.; Jin, Shuangshuang

    2009-10-03

    Small signal stability problems are one of the major threats to grid stability and reliability in California and the western U.S. power grid. An unstable oscillatory mode can cause large-amplitude oscillations and may result in system breakup and large-scale blackouts. There have been several incidents of system-wide oscillations. Of them, the most notable is the August 10, 1996 western system breakup produced as a result of undamped system-wide oscillations. There is a great need for real-time monitoring of small-signal oscillations in the system. In power systems, a small-signal oscillation is the result of poor electromechanical damping. Considerable understanding and literature have been developed on the small-signal stability problem over the past 50+ years. These studies have been mainly based on a linearized system model and eigenvalue analysis of its characteristic matrix. However, its practical feasibility is greatly limited as power system models have been found inadequate in describing real-time operating conditions. Significant efforts have been devoted to monitoring system oscillatory behaviors from real-time measurements in the past 20 years. The deployment of phasor measurement units (PMU) provides high-precision time-synchronized data needed for estimating oscillation modes. Measurement-based modal analysis, also known as ModeMeter, uses real-time phasor measure-ments to estimate system oscillation modes and their damping. Low damping indicates potential system stability issues. Oscillation alarms can be issued when the power system is lightly damped. A good oscillation alarm tool can provide time for operators to take remedial reaction and reduce the probability of a system breakup as a result of a light damping condition. Real-time oscillation monitoring requires ModeMeter algorithms to have the capability to work with various kinds of measurements: disturbance data (ringdown signals), noise probing data, and ambient data. Several measurement

  6. A new algorithm to diagnose atrial ectopic origin from multi lead ECG systems--insights from 3D virtual human atria and torso.

    PubMed

    Alday, Erick A Perez; Colman, Michael A; Langley, Philip; Butters, Timothy D; Higham, Jonathan; Workman, Antony J; Hancox, Jules C; Zhang, Henggui

    2015-01-01

    Rapid atrial arrhythmias such as atrial fibrillation (AF) predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG) can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP) during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation) were compared to those observed experimentally (obtained from the 64-lead ECG system), showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed algorithms. PMID

  7. A new algorithm to diagnose atrial ectopic origin from multi lead ECG systems--insights from 3D virtual human atria and torso.

    PubMed

    Alday, Erick A Perez; Colman, Michael A; Langley, Philip; Butters, Timothy D; Higham, Jonathan; Workman, Antony J; Hancox, Jules C; Zhang, Henggui

    2015-01-01

    Rapid atrial arrhythmias such as atrial fibrillation (AF) predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG) can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP) during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation) were compared to those observed experimentally (obtained from the 64-lead ECG system), showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed algorithms.

  8. A New Algorithm to Diagnose Atrial Ectopic Origin from Multi Lead ECG Systems - Insights from 3D Virtual Human Atria and Torso

    PubMed Central

    Alday, Erick A. Perez; Colman, Michael A.; Langley, Philip; Butters, Timothy D.; Higham, Jonathan; Workman, Antony J.; Hancox, Jules C.; Zhang, Henggui

    2015-01-01

    Rapid atrial arrhythmias such as atrial fibrillation (AF) predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG) can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP) during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation) were compared to those observed experimentally (obtained from the 64-lead ECG system), showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed algorithms. PMID

  9. Origins.

    ERIC Educational Resources Information Center

    Online-Offline, 1999

    1999-01-01

    Provides an annotated list of resources dealing with the theme of origins of life, the universe, and traditions. Includes Web sites, videos, books, audio materials, and magazines with appropriate grade levels and/or subject disciplines indicated; professional resources; and learning activities. (LRW)

  10. Development of a biomimetic robotic fish and its control algorithm.

    PubMed

    Yu, Junzhi; Tan, Min; Wang, Shuo; Chen, Erkui

    2004-08-01

    This paper is concerned with the design of a robotic fish and its motion control algorithms. A radio-controlled, four-link biomimetic robotic fish is developed using a flexible posterior body and an oscillating foil as a propeller. The swimming speed of the robotic fish is adjusted by modulating joint's oscillating frequency, and its orientation is tuned by different joint's deflections. Since the motion control of a robotic fish involves both hydrodynamics of the fluid environment and dynamics of the robot, it is very difficult to establish a precise mathematical model employing purely analytical methods. Therefore, the fish's motion control task is decomposed into two control systems. The online speed control implements a hybrid control strategy and a proportional-integral-derivative (PID) control algorithm. The orientation control system is based on a fuzzy logic controller. In our experiments, a point-to-point (PTP) control algorithm is implemented and an overhead vision system is adopted to provide real-time visual feedback. The experimental results confirm the effectiveness of the proposed algorithms.

  11. Development of antibiotic regimens using graph based evolutionary algorithms.

    PubMed

    Corns, Steven M; Ashlock, Daniel A; Bryden, Kenneth M

    2013-12-01

    This paper examines the use of evolutionary algorithms in the development of antibiotic regimens given to production animals. A model is constructed that combines the lifespan of the animal and the bacteria living in the animal's gastro-intestinal tract from the early finishing stage until the animal reaches market weight. This model is used as the fitness evaluation for a set of graph based evolutionary algorithms to assess the impact of diversity control on the evolving antibiotic regimens. The graph based evolutionary algorithms have two objectives: to find an antibiotic treatment regimen that maintains the weight gain and health benefits of antibiotic use and to reduce the risk of spreading antibiotic resistant bacteria. This study examines different regimens of tylosin phosphate use on bacteria populations divided into Gram positive and Gram negative types, with a focus on Campylobacter spp. Treatment regimens were found that provided decreased antibiotic resistance relative to conventional methods while providing nearly the same benefits as conventional antibiotic regimes. By using a graph to control the information flow in the evolutionary algorithm, a variety of solutions along the Pareto front can be found automatically for this and other multi-objective problems.

  12. Data inversion algorithm development for the hologen occultation experiment

    NASA Technical Reports Server (NTRS)

    Gordley, Larry L.; Mlynczak, Martin G.

    1986-01-01

    The successful retrieval of atmospheric parameters from radiometric measurement requires not only the ability to do ideal radiometric calculations, but also a detailed understanding of instrument characteristics. Therefore a considerable amount of time was spent in instrument characterization in the form of test data analysis and mathematical formulation. Analyses of solar-to-reference interference (electrical cross-talk), detector nonuniformity, instrument balance error, electronic filter time-constants and noise character were conducted. A second area of effort was the development of techniques for the ideal radiometric calculations required for the Halogen Occultation Experiment (HALOE) data reduction. The computer code for these calculations must be extremely complex and fast. A scheme for meeting these requirements was defined and the algorithms needed form implementation are currently under development. A third area of work included consulting on the implementation of the Emissivity Growth Approximation (EGA) method of absorption calculation into a HALOE broadband radiometer channel retrieval algorithm.

  13. SMMR Simulator radiative transfer calibration model. 2: Algorithm development

    NASA Technical Reports Server (NTRS)

    Link, S.; Calhoon, C.; Krupp, B.

    1980-01-01

    Passive microwave measurements performed from Earth orbit can be used to provide global data on a wide range of geophysical and meteorological phenomena. A Scanning Multichannel Microwave Radiometer (SMMR) is being flown on the Nimbus-G satellite. The SMMR Simulator duplicates the frequency bands utilized in the spacecraft instruments through an amalgamate of radiometer systems. The algorithm developed utilizes data from the fall 1978 NASA CV-990 Nimbus-G underflight test series and subsequent laboratory testing.

  14. Computational Fluid Dynamics. [numerical methods and algorithm development

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This collection of papers was presented at the Computational Fluid Dynamics (CFD) Conference held at Ames Research Center in California on March 12 through 14, 1991. It is an overview of CFD activities at NASA Lewis Research Center. The main thrust of computational work at Lewis is aimed at propulsion systems. Specific issues related to propulsion CFD and associated modeling will also be presented. Examples of results obtained with the most recent algorithm development will also be presented.

  15. Development of an Inverse Algorithm for Resonance Inspection

    SciTech Connect

    Lai, Canhai; Xu, Wei; Sun, Xin

    2012-10-01

    Resonance inspection (RI), which employs the natural frequency spectra shift between the good and the anomalous part populations to detect defects, is a non-destructive evaluation (NDE) technique with many advantages such as low inspection cost, high testing speed, and broad applicability to structures with complex geometry compared to other contemporary NDE methods. It has already been widely used in the automobile industry for quality inspections of safety critical parts. Unlike some conventionally used NDE methods, the current RI technology is unable to provide details, i.e. location, dimension, or types, of the flaws for the discrepant parts. Such limitation severely hinders its wide spread applications and further development. In this study, an inverse RI algorithm based on maximum correlation function is proposed to quantify the location and size of flaws for a discrepant part. A dog-bone shaped stainless steel sample with and without controlled flaws are used for algorithm development and validation. The results show that multiple flaws can be accurately pinpointed back using the algorithms developed, and the prediction accuracy decreases with increasing flaw numbers and decreasing distance between flaws.

  16. Origins.

    PubMed

    Weinberg, S

    1985-10-01

    The farthest of the galaxies that can be seen through the large ground-based telescopes of modern astronomy, such as those on La Palma in the Canary Islands, are so far away that they appear as they did close to the time of the origin of the universe, perhaps some 10 billion years ago. Much has been learned, and much has still to be learned, about the young universe from optical and radio telescopes, but these instruments cannot be used to look directly at the universe in its first few hundred thousand years. Instead, they are used to search the relatively recent past for relics of much earlier times. Together with experiments planned for the next generation of elementary particle accelerators, astronomical observations should continue to extend what is known about the universe backward in time to the Big Bang and may eventually help to reveal the origins of the physical laws that govern the universe.

  17. Development of a novel constellation based landmark detection algorithm

    NASA Astrophysics Data System (ADS)

    Ghayoor, Ali; Vaidya, Jatin G.; Johnson, Hans J.

    2013-03-01

    Anatomical landmarks such as the anterior commissure (AC) and posterior commissure (PC) are commonly used by researchers for co-registration of images. In this paper, we present a novel, automated approach for landmark detection that combines morphometric constraining and statistical shape models to provide accurate estimation of landmark points. This method is made robust to large rotations in initial head orientation by extracting extra information of the eye centers using a radial Hough transform and exploiting the centroid of head mass (CM) using a novel estimation approach. To evaluate the effectiveness of this method, the algorithm is trained on a set of 20 images with manually selected landmarks, and a test dataset is used to compare the automatically detected against the manually detected landmark locations of the AC, PC, midbrain-pons junction (MPJ), and fourth ventricle notch (VN4). The results show that the proposed method is accurate as the average error between the automatically and manually labeled landmark points is less than 1 mm. Also, the algorithm is highly robust as it was successfully run on a large dataset that included different kinds of images with various orientation, spacing, and origin.

  18. Shared memory, cache, and frontwidth considerations in multifrontal algorithm development

    SciTech Connect

    Benner, R.E.

    1986-01-23

    A concurrent, multifrontal algorithm (Benner and Weigand 1986) for solution of finite element equations was modified to better use the cache and shared memories on the ELXSI 6400, and to achieve better load balancing between 'child' processes via frontwidth reduction. The changes were also tailored to use distributed memory machines efficiently by making most local to individual processors. The test code initially used 8 Mbytes of incached shared memory and 155 cp (concurrent processor) sec (a speedup of 1.4) when run on 4 processors. The changes left only 50 Kbytes of uncached, and 470 Kbytes of cached, shared memory, plus 530 Kbytes of data local to each 'child' process. Total cp time was reduced to 57 sec and speedup increased to 2.8 on 4 processors. Based on those results an addition to the ELXSI multitasking software, asynchronous I/O between processes, is proposed that would further decrease the shared memory requirements of the algorithm and make the ELXSI look like a distributed memory machine as far as algorithm development is concerned. This would make the ELXSI an extremely useful tool for further development of special-purpose, finite element computations. 16 refs., 8 tabs.

  19. Developing Information Power Grid Based Algorithms and Software

    NASA Technical Reports Server (NTRS)

    Dongarra, Jack

    1998-01-01

    This exploratory study initiated our effort to understand performance modeling on parallel systems. The basic goal of performance modeling is to understand and predict the performance of a computer program or set of programs on a computer system. Performance modeling has numerous applications, including evaluation of algorithms, optimization of code implementations, parallel library development, comparison of system architectures, parallel system design, and procurement of new systems. Our work lays the basis for the construction of parallel libraries that allow for the reconstruction of application codes on several distinct architectures so as to assure performance portability. Following our strategy, once the requirements of applications are well understood, one can then construct a library in a layered fashion. The top level of this library will consist of architecture-independent geometric, numerical, and symbolic algorithms that are needed by the sample of applications. These routines should be written in a language that is portable across the targeted architectures.

  20. The development of a whole-body algorithm

    NASA Technical Reports Server (NTRS)

    Kay, F. J.

    1973-01-01

    The whole-body algorithm is envisioned as a mathematical model that utilizes human physiology to simulate the behavior of vital body systems. The objective of this model is to determine the response of selected body parameters within these systems to various input perturbations, or stresses. Perturbations of interest are exercise, chemical unbalances, gravitational changes and other abnormal environmental conditions. This model provides for a study of man's physiological response in various space applications, underwater applications, normal and abnormal workloads and environments, and the functioning of the system with physical impairments or decay of functioning components. Many methods or approaches to the development of a whole-body algorithm are considered. Of foremost concern is the determination of the subsystems to be included, the detail of the subsystems and the interaction between the subsystems.

  1. Mechanical origins of rightward torsion in early chick brain development

    NASA Astrophysics Data System (ADS)

    Chen, Zi; Guo, Qiaohang; Dai, Eric; Taber, Larry

    2015-03-01

    During early development, the neural tube of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This torsional deformation is one of the major organ-level left-right asymmetry events in development. Previous studies suggested that bending is mainly due to differential growth, however, the mechanism for torsion remains poorly understood. Since the heart almost always loops rightwards that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is lacking, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. Moreover, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model and a 3D printed physical model are employed to help interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, and further reveals that the asymmetric development in one organ can induce the asymmetry of another developing organ through mechanics, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''. Z.C. is supported by the Society in Science - Branco Weiss fellowship, administered by ETH Zurich. L.A.T acknowledges the support from NIH Grants R01 GM075200 and R01 NS070918.

  2. Algorithm for automatic forced spirometry quality assessment: technological developments.

    PubMed

    Melia, Umberto; Burgos, Felip; Vallverdú, Montserrat; Velickovski, Filip; Lluch-Ariet, Magí; Roca, Josep; Caminal, Pere

    2014-01-01

    We hypothesized that the implementation of automatic real-time assessment of quality of forced spirometry (FS) may significantly enhance the potential for extensive deployment of a FS program in the community. Recent studies have demonstrated that the application of quality criteria defined by the ATS/ERS (American Thoracic Society/European Respiratory Society) in commercially available equipment with automatic quality assessment can be markedly improved. To this end, an algorithm for assessing quality of FS automatically was reported. The current research describes the mathematical developments of the algorithm. An innovative analysis of the shape of the spirometric curve, adding 23 new metrics to the traditional 4 recommended by ATS/ERS, was done. The algorithm was created through a two-step iterative process including: (1) an initial version using the standard FS curves recommended by the ATS; and, (2) a refined version using curves from patients. In each of these steps the results were assessed against one expert's opinion. Finally, an independent set of FS curves from 291 patients was used for validation purposes. The novel mathematical approach to characterize the FS curves led to appropriate FS classification with high specificity (95%) and sensitivity (96%). The results constitute the basis for a successful transfer of FS testing to non-specialized professionals in the community.

  3. Collaborative workbench for cyberinfrastructure to accelerate science algorithm development

    NASA Astrophysics Data System (ADS)

    Ramachandran, R.; Maskey, M.; Kuo, K.; Lynnes, C.

    2013-12-01

    There are significant untapped resources for information and knowledge creation within the Earth Science community in the form of data, algorithms, services, analysis workflows or scripts, and the related knowledge about these resources. Despite the huge growth in social networking and collaboration platforms, these resources often reside on an investigator's workstation or laboratory and are rarely shared. A major reason for this is that there are very few scientific collaboration platforms, and those that exist typically require the use of a new set of analysis tools and paradigms to leverage the shared infrastructure. As a result, adoption of these collaborative platforms for science research is inhibited by the high cost to an individual scientist of switching from his or her own familiar environment and set of tools to a new environment and tool set. This presentation will describe an ongoing project developing an Earth Science Collaborative Workbench (CWB). The CWB approach will eliminate this barrier by augmenting a scientist's current research environment and tool set to allow him or her to easily share diverse data and algorithms. The CWB will leverage evolving technologies such as commodity computing and social networking to design an architecture for scalable collaboration that will support the emerging vision of an Earth Science Collaboratory. The CWB is being implemented on the robust and open source Eclipse framework and will be compatible with widely used scientific analysis tools such as IDL. The myScience Catalog built into CWB will capture and track metadata and provenance about data and algorithms for the researchers in a non-intrusive manner with minimal overhead. Seamless interfaces to multiple Cloud services will support sharing algorithms, data, and analysis results, as well as access to storage and computer resources. A Community Catalog will track the use of shared science artifacts and manage collaborations among researchers.

  4. Leadership development in the age of the algorithm.

    PubMed

    Buckingham, Marcus

    2012-06-01

    By now we expect personalized content--it's routinely served up by online retailers and news services, for example. But the typical leadership development program still takes a formulaic, one-size-fits-all approach. And it rarely happens that an excellent technique can be effectively transferred from one leader to all others. Someone trying to adopt a practice from a leader with a different style usually seems stilted and off--a Franken-leader. Breakthrough work at Hilton Hotels and other organizations shows how companies can use an algorithmic model to deliver training tips uniquely suited to each individual's style. It's a five-step process: First, a company must choose a tool with which to identify each person's leadership type. Second, it should assess its best leaders, and third, it should interview them about their techniques. Fourth, it should use its algorithmic model to feed tips drawn from those techniques to developing leaders of the same type. And fifth, it should make the system dynamically intelligent, with user reactions sharpening the content and targeting of tips. The power of this kind of system--highly customized, based on peer-to-peer sharing, and continually evolving--will soon overturn the generic model of leadership development. And such systems will inevitably break through any one organization, until somewhere in the cloud the best leadership tips from all over are gathered, sorted, and distributed according to which ones suit which people best.

  5. Leadership development in the age of the algorithm.

    PubMed

    Buckingham, Marcus

    2012-06-01

    By now we expect personalized content--it's routinely served up by online retailers and news services, for example. But the typical leadership development program still takes a formulaic, one-size-fits-all approach. And it rarely happens that an excellent technique can be effectively transferred from one leader to all others. Someone trying to adopt a practice from a leader with a different style usually seems stilted and off--a Franken-leader. Breakthrough work at Hilton Hotels and other organizations shows how companies can use an algorithmic model to deliver training tips uniquely suited to each individual's style. It's a five-step process: First, a company must choose a tool with which to identify each person's leadership type. Second, it should assess its best leaders, and third, it should interview them about their techniques. Fourth, it should use its algorithmic model to feed tips drawn from those techniques to developing leaders of the same type. And fifth, it should make the system dynamically intelligent, with user reactions sharpening the content and targeting of tips. The power of this kind of system--highly customized, based on peer-to-peer sharing, and continually evolving--will soon overturn the generic model of leadership development. And such systems will inevitably break through any one organization, until somewhere in the cloud the best leadership tips from all over are gathered, sorted, and distributed according to which ones suit which people best. PMID:22741421

  6. The development of solution algorithms for compressible flows

    NASA Astrophysics Data System (ADS)

    Slack, David Christopher

    Three main topics were examined. The first is the development and comparison of time integration schemes on 2-D unstructured meshes. Both explicit and implicit solution grids are presented. Cell centered and cell vertex finite volume upwind schemes using Roe's approximate Riemann solver are developed. The second topic involves an interactive adaptive remeshing algorithm which uses a frontal grid generator and is compared to a single grid calculation. The final topic examined is the capabilities developed for a structured 3-D code called GASP. The capabilities include: generalized chemistry and thermodynamic modeling, space marching, memory management through the use of binary C I/O, and algebraic and two equation eddy viscosity turbulence modeling. Results are given for Mach 1.7 3-D analytic forebody, a Mach 1.38 axisymmetric nozzle with hydrogen-air combustion, a Mach 14.15 deg ramp, and Mach 0.3 viscous flow over a flat plate.

  7. Development of a new metal artifact reduction algorithm by using an edge preserving method for CBCT imaging

    NASA Astrophysics Data System (ADS)

    Kim, Juhye; Nam, Haewon; Lee, Rena

    2015-07-01

    CT (computed tomography) images, metal materials such as tooth supplements or surgical clips can cause metal artifact and degrade image quality. In severe cases, this may lead to misdiagnosis. In this research, we developed a new MAR (metal artifact reduction) algorithm by using an edge preserving filter and the MATLAB program (Mathworks, version R2012a). The proposed algorithm consists of 6 steps: image reconstruction from projection data, metal segmentation, forward projection, interpolation, applied edge preserving smoothing filter, and new image reconstruction. For an evaluation of the proposed algorithm, we obtained both numerical simulation data and data for a Rando phantom. In the numerical simulation data, four metal regions were added into the Shepp Logan phantom for metal artifacts. The projection data of the metal-inserted Rando phantom were obtained by using a prototype CBCT scanner manufactured by medical engineering and medical physics (MEMP) laboratory research group in medical science at Ewha Womans University. After these had been adopted the proposed algorithm was performed, and the result were compared with the original image (with metal artifact without correction) and with a corrected image based on linear interpolation. Both visual and quantitative evaluations were done. Compared with the original image with metal artifacts and with the image corrected by using linear interpolation, both the numerical and the experimental phantom data demonstrated that the proposed algorithm reduced the metal artifact. In conclusion, the evaluation in this research showed that the proposed algorithm outperformed the interpolation based MAR algorithm. If an optimization and a stability evaluation of the proposed algorithm can be performed, the developed algorithm is expected to be an effective tool for eliminating metal artifacts even in commercial CT systems.

  8. Evaluation of Origin Ensemble algorithm for image reconstruction for pixelated solid-state detectors with large number of channels

    NASA Astrophysics Data System (ADS)

    Kolstein, M.; De Lorenzo, G.; Mikhaylova, E.; Chmeissani, M.; Ariño, G.; Calderón, Y.; Ozsahin, I.; Uzun, D.

    2013-04-01

    The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For PET scanners, conventional algorithms like Filtered Back-Projection (FBP) and Ordered Subset Expectation Maximization (OSEM) are straightforward to use and give good results. However, FBP presents difficulties for detectors with limited angular coverage like PEM and Compton gamma cameras, whereas OSEM has an impractically large time and memory consumption for a Compton gamma camera with a large number of channels. In this article, the Origin Ensemble (OE) algorithm is evaluated as an alternative algorithm for image reconstruction. Monte Carlo simulations of the PET design are used to compare the performance of OE, FBP and OSEM in terms of the bias, variance and average mean squared error (MSE) image quality metrics. For the PEM and Compton camera designs, results obtained with OE are presented.

  9. Origin and development of concepts of bipolar mixed states.

    PubMed

    Marneros, A

    2001-12-01

    This paper reviews the historical origins of the contemporaneous resurgence of interest in mixed states. This is a classical concept whose origins can be traced back to ancient times. In more modern times, already in the pre-Kraepelinian era we can find descriptions and classifications of "mixed states". For example, in his classification of mental disorders described "mixtures of exaltations and depression", and he distinguished among "mixed mood disorders", "mixed mental disorders", and "mixed volition disorders". Subsequently, (the father of empirical and biological psychiatric research in Germany) described the "mid-forms". Half a century later we encounter the crucial role of Emil Kraepelin and the development and systemization of his views between 1899 and 1913--leading to the characterization of such conditions as "depressive-anxious mania", "excited depression", and "stuporous mania". The remainder of this article focuses on the essential points of the first book on mixed states in the psychiatric literature: On The Mixed States of Manic-Depressive Insanity by. For much of the present 20th century nothing new emerges, followed by a contemporary renaissance of mixed states, particularly in the United States. The paper concludes with proposal of mixed states as temperament intruding into an episode of opposite polarity.

  10. Fat-constrained 18F-FDG PET reconstruction using Dixon MR imaging and the origin ensemble algorithm

    NASA Astrophysics Data System (ADS)

    Wülker, Christian; Heinzer, Susanne; Börnert, Peter; Renisch, Steffen; Prevrhal, Sven

    2015-03-01

    Combined PET/MR imaging allows to incorporate the high-resolution anatomical information delivered by MRI into the PET reconstruction algorithm for improvement of PET accuracy beyond standard corrections. We used the working hypothesis that glucose uptake in adipose tissue is low. Thus, our aim was to shift 18F-FDG PET signal into image regions with a low fat content. Dixon MR imaging can be used to generate fat-only images via the water/fat chemical shift difference. On the other hand, the Origin Ensemble (OE) algorithm, a novel Markov chain Monte Carlo method, allows to reconstruct PET data without the use of forward- and back projection operations. By adequate modifications to the Markov chain transition kernel, it is possible to include anatomical a priori knowledge into the OE algorithm. In this work, we used the OE algorithm to reconstruct PET data of a modified IEC/NEMA Body Phantom simulating body water/fat composition. Reconstruction was performed 1) natively, 2) informed with the Dixon MR fat image to down-weight 18F-FDG signal in fatty tissue compartments in favor of adjacent regions, and 3) informed with the fat image to up-weight 18F-FDG signal in fatty tissue compartments, for control purposes. Image intensity profiles confirmed the visibly improved contrast and reduced partial volume effect at water/fat interfaces. We observed a 17+/-2% increased SNR of hot lesions surrounded by fat, while image quality was almost completely retained in fat-free image regions. An additional in vivo experiment proved the applicability of the presented technique in practice, and again verified the beneficial impact of fat-constrained OE reconstruction on PET image quality.

  11. Advanced three-dimensional Eulerian hydrodynamic algorithm development

    SciTech Connect

    Rider, W.J.; Kothe, D.B.; Mosso, S.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project is to investigate, implement, and evaluate algorithms that have high potential for improving the robustness, fidelity and accuracy of three-dimensional Eulerian hydrodynamic simulations. Eulerian computations are necessary to simulate a number of important physical phenomena ranging from the molding process for metal parts to nuclear weapons safety issues to astrophysical phenomena such as that associated with a Type 2 supernovae. A number of algorithmic issues were explored in the course of this research including interface/volume tracking, surface physics integration, high resolution integration techniques, multilevel iterative methods, multimaterial hydrodynamics and coupling radiation with hydrodynamics. This project combines core strengths of several Laboratory divisions. The project has high institutional benefit given the renewed emphasis on numerical simulations in Science-Based Stockpile Stewardship and the Accelerated Strategic Computing Initiative and LANL`s tactical goals related to high performance computing and simulation.

  12. Development of a genetic algorithm for molecular scale catalyst design

    SciTech Connect

    McLeod, A.S.; Gladden, L.F.; Johnston, M.E.

    1997-04-01

    A genetic algorithm has been developed to determine the optimal design of a two-component catalyst for the diffusion-limited A + B AB{up_arrow} reaction in which each species is adsorbed specifically on one of two types of sites. Optimization of the distribution of catalytic sites on the surface is achieved by means of an evolutionary algorithm which repeatedly selects the more active surfaces from a population of possible solutions leading to a gradual improvement in the activity of the catalyst surface. A Monte Carlo simulation is used to determine the activity of each of the catalyst surfaces. It is found that for a reacting mixture composed of equal amounts of each component the optimal active site distribution is that of a checkerboard, this solution being approximately 25% more active than a random site distribution. Study of a range of reactant compositions has shown the optimal distribution of catalytically active sites to be dependent on the composition of the ratio of A to B in the reacting mixture. The potential for application of the optimization method introduced here to other catalysts systems is discussed. 27 refs., 7 figs.

  13. Development of a generally applicable morphokinetic algorithm capable of predicting the implantation potential of embryos transferred on Day 3

    PubMed Central

    Petersen, Bjørn Molt; Boel, Mikkel; Montag, Markus; Gardner, David K.

    2016-01-01

    STUDY QUESTION Can a generally applicable morphokinetic algorithm suitable for Day 3 transfers of time-lapse monitored embryos originating from different culture conditions and fertilization methods be developed for the purpose of supporting the embryologist's decision on which embryo to transfer back to the patient in assisted reproduction? SUMMARY ANSWER The algorithm presented here can be used independently of culture conditions and fertilization method and provides predictive power not surpassed by other published algorithms for ranking embryos according to their blastocyst formation potential. WHAT IS KNOWN ALREADY Generally applicable algorithms have so far been developed only for predicting blastocyst formation. A number of clinics have reported validated implantation prediction algorithms, which have been developed based on clinic-specific culture conditions and clinical environment. However, a generally applicable embryo evaluation algorithm based on actual implantation outcome has not yet been reported. STUDY DESIGN, SIZE, DURATION Retrospective evaluation of data extracted from a database of known implantation data (KID) originating from 3275 embryos transferred on Day 3 conducted in 24 clinics between 2009 and 2014. The data represented different culture conditions (reduced and ambient oxygen with various culture medium strategies) and fertilization methods (IVF, ICSI). The capability to predict blastocyst formation was evaluated on an independent set of morphokinetic data from 11 218 embryos which had been cultured to Day 5. PARTICIPANTS/MATERIALS, SETTING, METHODS The algorithm was developed by applying automated recursive partitioning to a large number of annotation types and derived equations, progressing to a five-fold cross-validation test of the complete data set and a validation test of different incubation conditions and fertilization methods. The results were expressed as receiver operating characteristics curves using the area under the

  14. The Big Bang Model: Its Origin and Development

    NASA Astrophysics Data System (ADS)

    Alpher, Ralph A.

    The current Big Bang Model had its origin in Einstein's attempt to model a static cosmos, based on his general theory of relativity. Friedmann and Lemaitre, as well as de Sitter, further developed the model to cover other options, including nonstatic behavior. Lemaitre in the 1930s and, particularly, Gamow in 1946 first put physics into the nonstatic model. By 1946 there had been significant developments in the mathematics of the model due to Robertson, Walker, Tolman and many others. The Hubble law had given an essential observational basis for the Big Bang, as did the attribution of cosmic significance to element abundances by Goldschmidt. Following early suggestions by George Gamow, the first attempt to explain nucleosynthesis in a hot, dense, early universe was done by Alpher, Bethe and Gamow in 1948, a paper whose principal importance was that it suggested that the early universe was in fact hot and dense, and that hydrogen and helium and perhaps other light elements were primeval. In that same year Alpher and Herman first predicted a cosmic background radiation at 5 kelvin as an essential feature of the model. The Hubble expansion rate, the primordial and stellar abundances of the elements, and the cosmic microwave background are major pillars today for the Big Bang model.

  15. Developing JSequitur to Study the Hierarchical Structure of Biological Sequences in a Grammatical Inference Framework of String Compression Algorithms.

    PubMed

    Galbadrakh, Bulgan; Lee, Kyung-Eun; Park, Hyun-Seok

    2012-12-01

    Grammatical inference methods are expected to find grammatical structures hidden in biological sequences. One hopes that studies of grammar serve as an appropriate tool for theory formation. Thus, we have developed JSequitur for automatically generating the grammatical structure of biological sequences in an inference framework of string compression algorithms. Our original motivation was to find any grammatical traits of several cancer genes that can be detected by string compression algorithms. Through this research, we could not find any meaningful unique traits of the cancer genes yet, but we could observe some interesting traits in regards to the relationship among gene length, similarity of sequences, the patterns of the generated grammar, and compression rate.

  16. Stoffenmanager exposure model: development of a quantitative algorithm.

    PubMed

    Tielemans, Erik; Noy, Dook; Schinkel, Jody; Heussen, Henri; Van Der Schaaf, Doeke; West, John; Fransman, Wouter

    2008-08-01

    In The Netherlands, the web-based tool called 'Stoffenmanager' was initially developed to assist small- and medium-sized enterprises to prioritize and control risks of handling chemical products in their workplaces. The aim of the present study was to explore the accuracy of the Stoffenmanager exposure algorithm. This was done by comparing its semi-quantitative exposure rankings for specific substances with exposure measurements collected from several occupational settings to derive a quantitative exposure algorithm. Exposure data were collected using two strategies. First, we conducted seven surveys specifically for validation of the Stoffenmanager. Second, existing occupational exposure data sets were collected from various sources. This resulted in 378 and 320 measurements for solid and liquid scenarios, respectively. The Spearman correlation coefficients between Stoffenmanager scores and exposure measurements appeared to be good for handling solids (r(s) = 0.80, N = 378, P < 0.0001) and liquid scenarios (r(s) = 0.83, N = 320, P < 0.0001). However, the correlation for liquid scenarios appeared to be lower when calculated separately for sets of volatile substances with a vapour pressure >10 Pa (r(s) = 0.56, N = 104, P < 0.0001) and non-volatile substances with a vapour pressure < or =10 Pa (r(s) = 0.53, N = 216, P < 0.0001). The mixed-effect regression models with natural log-transformed Stoffenmanager scores as independent parameter explained a substantial part of the total exposure variability (52% for solid scenarios and 76% for liquid scenarios). Notwithstanding the good correlation, the data show substantial variability in exposure measurements given a certain Stoffenmanager score. The overall performance increases our confidence in the use of the Stoffenmanager as a generic tool for risk assessment. The mixed-effect regression models presented in this paper may be used for assessment of so-called reasonable worst case exposures. This evaluation is

  17. Development and evaluation of thermal model reduction algorithms for spacecraft

    NASA Astrophysics Data System (ADS)

    Deiml, Michael; Suderland, Martin; Reiss, Philipp; Czupalla, Markus

    2015-05-01

    This paper is concerned with the topic of the reduction of thermal models of spacecraft. The work presented here has been conducted in cooperation with the company OHB AG, formerly Kayser-Threde GmbH, and the Institute of Astronautics at Technische Universität München with the goal to shorten and automatize the time-consuming and manual process of thermal model reduction. The reduction of thermal models can be divided into the simplification of the geometry model for calculation of external heat flows and radiative couplings and into the reduction of the underlying mathematical model. For simplification a method has been developed which approximates the reduced geometry model with the help of an optimization algorithm. Different linear and nonlinear model reduction techniques have been evaluated for their applicability in reduction of the mathematical model. Thereby the compatibility with the thermal analysis tool ESATAN-TMS is of major concern, which restricts the useful application of these methods. Additional model reduction methods have been developed, which account to these constraints. The Matrix Reduction method allows the approximation of the differential equation to reference values exactly expect for numerical errors. The summation method enables a useful, applicable reduction of thermal models that can be used in industry. In this work a framework for model reduction of thermal models has been created, which can be used together with a newly developed graphical user interface for the reduction of thermal models in industry.

  18. Molecular descriptor subset selection in theoretical peptide quantitative structure-retention relationship model development using nature-inspired optimization algorithms.

    PubMed

    Žuvela, Petar; Liu, J Jay; Macur, Katarzyna; Bączek, Tomasz

    2015-10-01

    In this work, performance of five nature-inspired optimization algorithms, genetic algorithm (GA), particle swarm optimization (PSO), artificial bee colony (ABC), firefly algorithm (FA), and flower pollination algorithm (FPA), was compared in molecular descriptor selection for development of quantitative structure-retention relationship (QSRR) models for 83 peptides that originate from eight model proteins. The matrix with 423 descriptors was used as input, and QSRR models based on selected descriptors were built using partial least squares (PLS), whereas root mean square error of prediction (RMSEP) was used as a fitness function for their selection. Three performance criteria, prediction accuracy, computational cost, and the number of selected descriptors, were used to evaluate the developed QSRR models. The results show that all five variable selection methods outperform interval PLS (iPLS), sparse PLS (sPLS), and the full PLS model, whereas GA is superior because of its lowest computational cost and higher accuracy (RMSEP of 5.534%) with a smaller number of variables (nine descriptors). The GA-QSRR model was validated initially through Y-randomization. In addition, it was successfully validated with an external testing set out of 102 peptides originating from Bacillus subtilis proteomes (RMSEP of 22.030%). Its applicability domain was defined, from which it was evident that the developed GA-QSRR exhibited strong robustness. All the sources of the model's error were identified, thus allowing for further application of the developed methodology in proteomics.

  19. Origins and development of the Cauchy problem in general relativity

    NASA Astrophysics Data System (ADS)

    Ringström, Hans

    2015-06-01

    The seminal work of Yvonne Choquet-Bruhat published in 1952 demonstrates that it is possible to formulate Einstein's equations as an initial value problem. The purpose of this article is to describe the background to and impact of this achievement, as well as the result itself. In some respects, the idea of viewing the field equations of general relativity as a system of evolution equations goes back to Einstein himself; in an argument justifying that gravitational waves propagate at the speed of light, Einstein used a special choice of coordinates to derive a system of wave equations for the linear perturbations on a Minkowski background. Over the following decades, Hilbert, de Donder, Lanczos, Darmois and many others worked to put Einstein's ideas on a more solid footing. In fact, the issue of local uniqueness (giving a rigorous justification for the statement that the speed of propagation of the gravitational field is bounded by that of light) was already settled in the 1930s by the work of Stellmacher. However, the first person to demonstrate both local existence and uniqueness in a setting in which the notion of finite speed of propagation makes sense was Yvonne Choquet-Bruhat. In this sense, her work lays the foundation for the formulation of Einstein's equations as an initial value problem. Following a description of the results of Choquet-Bruhat, we discuss the development of three research topics that have their origin in her work. The first one is local existence. One reason for addressing it is that it is at the heart of the original paper. Moreover, it is still an active and important research field, connected to the problem of characterizing the asymptotic behaviour of solutions that blow up in finite time. As a second topic, we turn to the questions of global uniqueness and strong cosmic censorship. These questions are of fundamental importance to anyone interested in justifying that the Cauchy problem makes sense globally. They are also closely

  20. Developing Information Power Grid Based Algorithms and Software

    NASA Technical Reports Server (NTRS)

    Dongarra, Jack

    1998-01-01

    This was an exploratory study to enhance our understanding of problems involved in developing large scale applications in a heterogeneous distributed environment. It is likely that the large scale applications of the future will be built by coupling specialized computational modules together. For example, efforts now exist to couple ocean and atmospheric prediction codes to simulate a more complete climate system. These two applications differ in many respects. They have different grids, the data is in different unit systems and the algorithms for inte,-rating in time are different. In addition the code for each application is likely to have been developed on different architectures and tend to have poor performance when run on an architecture for which the code was not designed, if it runs at all. Architectural differences may also induce differences in data representation which effect precision and convergence criteria as well as data transfer issues. In order to couple such dissimilar codes some form of translation must be present. This translation should be able to handle interpolation from one grid to another as well as construction of the correct data field in the correct units from available data. Even if a code is to be developed from scratch, a modular approach will likely be followed in that standard scientific packages will be used to do the more mundane tasks such as linear algebra or Fourier transform operations. This approach allows the developers to concentrate on their science rather than becoming experts in linear algebra or signal processing. Problems associated with this development approach include difficulties associated with data extraction and translation from one module to another, module performance on different nodal architectures, and others. In addition to these data and software issues there exists operational issues such as platform stability and resource management.

  1. Understanding disordered systems through numerical simulation and algorithm development

    NASA Astrophysics Data System (ADS)

    Sweeney, Sean Michael

    Disordered systems arise in many physical contexts. Not all matter is uniform, and impurities or heterogeneities can be modeled by fixed random disorder. Numerous complex networks also possess fixed disorder, leading to applications in transportation systems, telecommunications, social networks, and epidemic modeling, to name a few. Due to their random nature and power law critical behavior, disordered systems are difficult to study analytically. Numerical simulation can help overcome this hurdle by allowing for the rapid computation of system states. In order to get precise statistics and extrapolate to the thermodynamic limit, large systems must be studied over many realizations. Thus, innovative algorithm development is essential in order reduce memory or running time requirements of simulations. This thesis presents a review of disordered systems, as well as a thorough study of two particular systems through numerical simulation, algorithm development and optimization, and careful statistical analysis of scaling properties. Chapter 1 provides a thorough overview of disordered systems, the history of their study in the physics community, and the development of techniques used to study them. Topics of quenched disorder, phase transitions, the renormalization group, criticality, and scale invariance are discussed. Several prominent models of disordered systems are also explained. Lastly, analysis techniques used in studying disordered systems are covered. In Chapter 2, minimal spanning trees on critical percolation clusters are studied, motivated in part by an analytic perturbation expansion by Jackson and Read that I check against numerical calculations. This system has a direct mapping to the ground state of the strongly disordered spin glass. We compute the path length fractal dimension of these trees in dimensions d = {2, 3, 4, 5} and find our results to be compatible with the analytic results suggested by Jackson and Read. In Chapter 3, the random bond Ising

  2. Nonlinear Motion Cueing Algorithm: Filtering at Pilot Station and Development of the Nonlinear Optimal Filters for Pitch and Roll

    NASA Technical Reports Server (NTRS)

    Zaychik, Kirill B.; Cardullo, Frank M.

    2012-01-01

    Telban and Cardullo have developed and successfully implemented the non-linear optimal motion cueing algorithm at the Visual Motion Simulator (VMS) at the NASA Langley Research Center in 2005. The latest version of the non-linear algorithm performed filtering of motion cues in all degrees-of-freedom except for pitch and roll. This manuscript describes the development and implementation of the non-linear optimal motion cueing algorithm for the pitch and roll degrees of freedom. Presented results indicate improved cues in the specified channels as compared to the original design. To further advance motion cueing in general, this manuscript describes modifications to the existing algorithm, which allow for filtering at the location of the pilot's head as opposed to the centroid of the motion platform. The rational for such modification to the cueing algorithms is that the location of the pilot's vestibular system must be taken into account as opposed to the off-set of the centroid of the cockpit relative to the center of rotation alone. Results provided in this report suggest improved performance of the motion cueing algorithm.

  3. Mars Entry Atmospheric Data System Modelling and Algorithm Development

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Beck, Roger E.; OKeefe, Stephen A.; Siemers, Paul; White, Brady; Engelund, Walter C.; Munk, Michelle M.

    2009-01-01

    The Mars Entry Atmospheric Data System (MEADS) is being developed as part of the Mars Science Laboratory (MSL), Entry, Descent, and Landing Instrumentation (MEDLI) project. The MEADS project involves installing an array of seven pressure transducers linked to ports on the MSL forebody to record the surface pressure distribution during atmospheric entry. These measured surface pressures are used to generate estimates of atmospheric quantities based on modeled surface pressure distributions. In particular, the quantities to be estimated from the MEADS pressure measurements include the total pressure, dynamic pressure, Mach number, angle of attack, and angle of sideslip. Secondary objectives are to estimate atmospheric winds by coupling the pressure measurements with the on-board Inertial Measurement Unit (IMU) data. This paper provides details of the algorithm development, MEADS system performance based on calibration, and uncertainty analysis for the aerodynamic and atmospheric quantities of interest. The work presented here is part of the MEDLI performance pre-flight validation and will culminate with processing flight data after Mars entry in 2012.

  4. Development of hybrid genetic algorithms for product line designs.

    PubMed

    Balakrishnan, P V Sundar; Gupta, Rakesh; Jacob, Varghese S

    2004-02-01

    In this paper, we investigate the efficacy of artificial intelligence (AI) based meta-heuristic techniques namely genetic algorithms (GAs), for the product line design problem. This work extends previously developed methods for the single product design problem. We conduct a large scale simulation study to determine the effectiveness of such an AI based technique for providing good solutions and bench mark the performance of this against the current dominant approach of beam search (BS). We investigate the potential advantages of pursuing the avenue of developing hybrid models and then implement and study such hybrid models using two very distinct approaches: namely, seeding the initial GA population with the BS solution, and employing the BS solution as part of the GA operator's process. We go on to examine the impact of two alternate string representation formats on the quality of the solutions obtained by the above proposed techniques. We also explicitly investigate a critical managerial factor of attribute importance in terms of its impact on the solutions obtained by the alternate modeling procedures. The alternate techniques are then evaluated, using statistical analysis of variance, on a fairy large number of data sets, as to the quality of the solutions obtained with respect to the state-of-the-art benchmark and in terms of their ability to provide multiple, unique product line options.

  5. A new radar technique for satellite rainfall algorithm development

    NASA Technical Reports Server (NTRS)

    Jameson, Arthur R.

    1987-01-01

    A potential new radar parameter was investigated for measuring rainfall, namely the summation of the phase shifts at horizontal and vertical polarizations due to propagation through precipitation. The proposed radar technique has several potential advantages over other approaches because it is insensitive to the drop size distribution and to the shapes of the raindrops. Such a parameter could greatly assist the development of satellite rainfall estimation algorithms by providing comparative measurements near the ground. It could also provide hydrologically useful information for such practical applications as urban hydrology. Results of the investigation showed that the parameters can not be measured by radar. However, a closely related radar parameter, propagation differential phase shift, can be readily measured using a polarization diversity radar. It is recommended that propagation differential phase shift be further investigated and developed for radar monitoring of rainfall using a polarization agile radar. It is also recommended that a prototype multiple frequency microwave link be constructed for attenuation measurements not possible by existing radar systems.

  6. Algorithm development for Prognostics and Health Management (PHM).

    SciTech Connect

    Swiler, Laura Painton; Campbell, James E.; Doser, Adele Beatrice; Lowder, Kelly S.

    2003-10-01

    This report summarizes the results of a three-year LDRD project on prognostics and health management. System failure over some future time interval (an alternative definition is the capability to predict the remaining useful life of a system). Prognostics are integrated with health monitoring (through inspections, sensors, etc.) to provide an overall PHM capability that optimizes maintenance actions and results in higher availability at a lower cost. Our goal in this research was to develop PHM tools that could be applied to a wide variety of equipment (repairable, non-repairable, manufacturing, weapons, battlefield equipment, etc.) and require minimal customization to move from one system to the next. Thus, our approach was to develop a toolkit of reusable software objects/components and architecture for their use. We have developed two software tools: an Evidence Engine and a Consequence Engine. The Evidence Engine integrates information from a variety of sources in order to take into account all the evidence that impacts a prognosis for system health. The Evidence Engine has the capability for feature extraction, trend detection, information fusion through Bayesian Belief Networks (BBN), and estimation of remaining useful life. The Consequence Engine involves algorithms to analyze the consequences of various maintenance actions. The Consequence Engine takes as input a maintenance and use schedule, spares information, and time-to-failure data on components, then generates maintenance and failure events, and evaluates performance measures such as equipment availability, mission capable rate, time to failure, and cost. This report summarizes the capabilities we have developed, describes the approach and architecture of the two engines, and provides examples of their use. 'Prognostics' refers to the capability to predict the probability of

  7. Algorithm development for deeply buried threat detection in GPR data

    NASA Astrophysics Data System (ADS)

    Reichman, Daniël.; Malof, Jordan M.; Collins, Leslie M.

    2016-05-01

    Ground penetrating radar (GPR) is a popular remote sensing modality for buried threat detection. Many algorithms have been developed to detect buried threats using GPR data. One on-going challenge with GPR is the detection of very deeply buried targets. In this work a detection approach is proposed that improves the detection of very deeply buried targets, and interestingly, shallow targets as well. First, it is shown that the signal of a target (the target "signature") is well localized in time, and well correlated with the target's burial depth. This motivates the proposed approach, where GPR data is split into two disjoint subsets: an early and late portion corresponding to the time at which shallow and deep target signatures appear, respectively. Experiments are conducted on real GPR data using the previously published histogram of oriented gradients (HOG) prescreener: a fast supervised processing method operated on HOG features. The results show substantial improvements in detection of very deeply buried targets (4.1% to 17.2%) and in overall detection performance (81.1% to 83.9%). Further, it is shown that the performance of the proposed approach is relatively insensitive to the time at which the data is split. These results suggest that other detection methods may benefit from depth-based processing as well.

  8. Toward Developing Genetic Algorithms to Aid in Critical Infrastructure Modeling

    SciTech Connect

    Not Available

    2007-05-01

    Today’s society relies upon an array of complex national and international infrastructure networks such as transportation, telecommunication, financial and energy. Understanding these interdependencies is necessary in order to protect our critical infrastructure. The Critical Infrastructure Modeling System, CIMS©, examines the interrelationships between infrastructure networks. CIMS© development is sponsored by the National Security Division at the Idaho National Laboratory (INL) in its ongoing mission for providing critical infrastructure protection and preparedness. A genetic algorithm (GA) is an optimization technique based on Darwin’s theory of evolution. A GA can be coupled with CIMS© to search for optimum ways to protect infrastructure assets. This includes identifying optimum assets to enforce or protect, testing the addition of or change to infrastructure before implementation, or finding the optimum response to an emergency for response planning. This paper describes the addition of a GA to infrastructure modeling for infrastructure planning. It first introduces the CIMS© infrastructure modeling software used as the modeling engine to support the GA. Next, the GA techniques and parameters are defined. Then a test scenario illustrates the integration with CIMS© and the preliminary results.

  9. Phase 2 development of Great Lakes algorithms for Nimbus-7 coastal zone color scanner

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1984-01-01

    A series of experiments have been conducted in the Great Lakes designed to evaluate the application of the NIMBUS-7 Coastal Zone Color Scanner (CZCS). Atmospheric and water optical models were used to relate surface and subsurface measurements to satellite measured radiances. Absorption and scattering measurements were reduced to obtain a preliminary optical model for the Great Lakes. Algorithms were developed for geometric correction, correction for Rayleigh and aerosol path radiance, and prediction of chlorophyll-a pigment and suspended mineral concentrations. The atmospheric algorithm developed compared favorably with existing algorithms and was the only algorithm found to adequately predict the radiance variations in the 670 nm band. The atmospheric correction algorithm developed was designed to extract needed algorithm parameters from the CZCS radiance values. The Gordon/NOAA ocean algorithms could not be demonstrated to work for Great Lakes waters. Predicted values of chlorophyll-a concentration compared favorably with expected and measured data for several areas of the Great Lakes.

  10. Origins, Form, and Development of the Son Jarocho: Veracruz, Mexico.

    ERIC Educational Resources Information Center

    Loza, Steven J.

    1982-01-01

    Son Jarocho (specifically from Veracruz) is a song-and-dance form originating in Spain and implanted in Mexico during 17th- and 18th-century colonization. The jarocho style of music today is one of Latin America's most unique forms, using one to four instruments and characterized by its distinctive rhythm. (LC)

  11. Origin and Development of Multilingual Education in Eritrea

    ERIC Educational Resources Information Center

    Asfaha, Yonas Mesfun

    2015-01-01

    In an attempt to describe the historical origins of multilingual education in Eritrea, Horn of Africa, this paper looks at how missionaries, European colonisers, successive Ethiopian rules in Eritrea and the independence movements that fought Ethiopia defined ethnic, religious and linguistic differences of communities in the country. These…

  12. The 1918 Education Act: Origins, Aims and Development

    ERIC Educational Resources Information Center

    Sherington, G. E.

    1976-01-01

    There has been some disagreement and confusion as to the origins of the 1918 Education Act, one of three major measures of twentieth-century English educational legislation. This article attempts to clarify and resolve that confusion. A fuller understanding of the aims of this important educational legislation is also explored. (Author/RK)

  13. Development of Great Lakes algorithms for the Nimbus-G coastal zone color scanner

    NASA Technical Reports Server (NTRS)

    Tanis, F. J.; Lyzenga, D. R.

    1981-01-01

    A series of experiments in the Great Lakes designed to evaluate the application of the Nimbus G satellite Coastal Zone Color Scanner (CZCS) were conducted. Absorption and scattering measurement data were reduced to obtain a preliminary optical model for the Great Lakes. Available optical models were used in turn to calculate subsurface reflectances for expected concentrations of chlorophyll-a pigment and suspended minerals. Multiple nonlinear regression techniques were used to derive CZCS water quality prediction equations from Great Lakes simulation data. An existing atmospheric model was combined with a water model to provide the necessary simulation data for evaluation of the preliminary CZCS algorithms. A CZCS scanner model was developed which accounts for image distorting scanner and satellite motions. This model was used in turn to generate mapping polynomials that define the transformation from the original image to one configured in a polyconic projection. Four computer programs (FORTRAN IV) for image transformation are presented.

  14. Developing a modified SEBAL algorithm that is responsive to advection by using limited weather data

    NASA Astrophysics Data System (ADS)

    Mkhwanazi, Mcebisi

    The use of Remote Sensing ET algorithms in water management, especially for agricultural purposes is increasing, and there are more models being introduced. The Surface Energy Balance Algorithm for Land (SEBAL) and its variant, Mapping Evapotranspiration with Internalized Calibration (METRIC) are some of the models that are being widely used. While SEBAL has several advantages over other RS models, including that it does not require prior knowledge of soil, crop and other ground details, it has the downside of underestimating evapotranspiration (ET) on days when there is advection, which may be in most cases in arid and semi-arid areas. METRIC, however has been modified to be able to account for advection, but in doing so it requires hourly weather data. In most developing countries, while accurate estimates of ET are required, the weather data necessary to use METRIC may not be available. This research therefore was meant to develop a modified version of SEBAL that would require minimal weather data that may be available in these areas, and still estimate ET accurately. The data that were used to develop this model were minimum and maximum temperatures, wind data, preferably the run of wind in the afternoon, and wet bulb temperature. These were used to quantify the advected energy that would increase ET in the field. This was a two-step process; the first was developing the model for standard conditions, which was described as a healthy cover of alfalfa, 40-60 cm tall and not short of water. Under standard conditions, when estimated ET using modified SEBAL was compared with lysimeter-measured ET, the modified SEBAL model had a Mean Bias Error (MBE) of 2.2 % compared to -17.1 % from the original SEBAL. The Root Mean Square Error (RMSE) was lower for the modified SEBAL model at 10.9 % compared to 25.1 % for the original SEBAL. The modified SEBAL model, developed on an alfalfa field in Rocky Ford, was then tested on other crops; beans and wheat. It was also tested on

  15. Developing new algorithms for estimating river discharge from SWOT

    NASA Astrophysics Data System (ADS)

    Pavelsky, T. M.; Durand, M. T.

    2012-12-01

    Flow of water through rivers is a critical component of the global hydrologic cycle, yet discharge on many of the world's rivers remains poorly constrained by ground-based observations. The planned NASA/CNES Surface Water and Ocean Topography (SWOT) satellite mission will provide concurrent observations of inundated area, water surface elevation, and its spatial derivative (surface slope) for rivers wider than 100 m (and perhaps as narrow as 50 m), which will allow a step-change improvement in our ability to characterize river discharge from space. New discharge algorithms must be developed to incorporate SWOT's unprecedented observations. While ground-based discharge is usually measured at river cross-sections, SWOT will estimate discharge over river reaches of variable length. Cross-sectional discharge is often estimated using slope-area scaling methods such as Manning's Equation, and modified forms of these equations could be used to estimate reach-averaged discharge. While some of the parameters required to estimate discharge are measured directly by SWOT, others including baseflow depth and channel roughness (e.g. Manning's n) are not. Promising new methods are under development to estimate baseflow depth in selected river reaches by extrapolating width-stage relationships. In contrast, channel roughness has received relatively little attention. By combining SWOT observations of several reaches over multiple overpasses, however, it may be possible to simultaneously derive both depth and channel roughness from SWOT observations alone. The principle in this method is to start from mass and momentum conservation, apply a slope-area method such as Manning's equation, assume the roughness coefficient and bathymetry are temporally-invariant, then solve for the unknowns by constraining over a number of overpasses. In principle, only four overpasses are needed for this method, but in practice more will likely be needed to obtain an accurate solution; the actual number

  16. Development of adaptive noise reduction filter algorithm for pediatric body images in a multi-detector CT

    NASA Astrophysics Data System (ADS)

    Nishimaru, Eiji; Ichikawa, Katsuhiro; Okita, Izumi; Ninomiya, Yuuji; Tomoshige, Yukihiro; Kurokawa, Takehiro; Ono, Yutaka; Nakamura, Yuko; Suzuki, Masayuki

    2008-03-01

    Recently, several kinds of post-processing image filters which reduce the noise of computed tomography (CT) images have been proposed. However, these image filters are mostly for adults. Because these are not very effective in small (< 20 cm) display fields of view (FOV), we cannot use them for pediatric body images (e.g., premature babies and infant children). We have developed a new noise reduction filter algorithm for pediatric body CT images. This algorithm is based on a 3D post-processing in which the output pixel values are calculated by nonlinear interpolation in z-directions on original volumetric-data-sets. This algorithm does not need the in-plane (axial plane) processing, so the spatial resolution does not change. From the phantom studies, our algorithm could reduce SD up to 40% without affecting the spatial resolution of x-y plane and z-axis, and improved the CNR up to 30%. This newly developed filter algorithm will be useful for the diagnosis and radiation dose reduction of the pediatric body CT images.

  17. Evolutionary origin of gastrulation: insights from sponge development

    PubMed Central

    2014-01-01

    Background The evolutionary origin of gastrulation—defined as a morphogenetic event that leads to the establishment of germ layers—remains a vexing question. Central to this debate is the evolutionary relationship between the cell layers of sponges (poriferans) and eumetazoan germ layers. Despite considerable attention, it remains unclear whether sponge cell layers undergo progressive fate determination akin to eumetazoan primary germ layer formation during gastrulation. Results Here we show by cell-labelling experiments in the demosponge Amphimedon queenslandica that the cell layers established during embryogenesis have no relationship to the cell layers of the juvenile. In addition, juvenile epithelial cells can transdifferentiate into a range of cell types and move between cell layers. Despite the apparent lack of cell layer and fate determination and stability in this sponge, the transcription factor GATA, a highly conserved eumetazoan endomesodermal marker, is expressed consistently in the inner layer of A. queenslandica larvae and juveniles. Conclusions Our results are compatible with sponge cell layers not undergoing progressive fate determination and thus not being homologous to eumetazoan germ layers. Nonetheless, the expression of GATA in the sponge inner cell layer suggests a shared ancestry with the eumetazoan endomesoderm, and that the ancestral role of GATA in specifying internalised cells may antedate the origin of germ layers. Together, these results support germ layers and gastrulation evolving early in eumetazoan evolution from pre-existing developmental programs used for the simple patterning of cells in the first multicellular animals. PMID:24678663

  18. Item Selection for the Development of Short Forms of Scales Using an Ant Colony Optimization Algorithm

    ERIC Educational Resources Information Center

    Leite, Walter L.; Huang, I-Chan; Marcoulides, George A.

    2008-01-01

    This article presents the use of an ant colony optimization (ACO) algorithm for the development of short forms of scales. An example 22-item short form is developed for the Diabetes-39 scale, a quality-of-life scale for diabetes patients, using a sample of 265 diabetes patients. A simulation study comparing the performance of the ACO algorithm and…

  19. The Origin and Development of the African Evaluation Guidelines

    ERIC Educational Resources Information Center

    Rouge, Jean-Charles

    2004-01-01

    In May 1990, the first evaluation seminar in Africa took place in Cote d'Ivoire. It was the first in a series of regional seminars on evaluation planned by the Development Assistance Committee (DAC) of the Organization for Economic Cooperation and Development (OECD). The seminar was jointly presented by the DAC and African Development Bank (ADB).…

  20. Thapsigargin, Origin, Chemistry, Structure-Activity Relationships and Prodrug Development.

    PubMed

    Quynh Doan, Nhu Thi; Christensen, Soren Brogger

    2015-01-01

    Thapsigargin was originally isolated from the roots of the Mediterranean umbelliferous plant Thapsia garganica in order to characterize the skin irritant principle. Characteristic chemical properties and semi-syntheses are reviewed. The biological activity was related to the subnanomolar affinity for the sarco/endoplasmic reticulum calcium ATPase. Prolonged inhibition of the pump afforded collapse of the calcium homeostasis and eventually apoptosis. Structure-activity relationships enabled design of an equipotent analogue containing a linker. Conjugation of the analogue containing the linker with peptides, which only are substrates for either prostate specific antigen (PSA) or prostate specific membrane antigen (PSMA) enabled design of prodrugs targeting a number of cancer diseases including prostate cancer (G115) and hepatocellular carcinoma (G202). Prodrug G202 has under the name of mipsagargin in phase II clinical trials shown promising properties against hepatocellular carcinoma.

  1. Thapsigargin, Origin, Chemistry, Structure-Activity Relationships and Prodrug Development.

    PubMed

    Quynh Doan, Nhu Thi; Christensen, Soren Brogger

    2015-01-01

    Thapsigargin was originally isolated from the roots of the Mediterranean umbelliferous plant Thapsia garganica in order to characterize the skin irritant principle. Characteristic chemical properties and semi-syntheses are reviewed. The biological activity was related to the subnanomolar affinity for the sarco/endoplasmic reticulum calcium ATPase. Prolonged inhibition of the pump afforded collapse of the calcium homeostasis and eventually apoptosis. Structure-activity relationships enabled design of an equipotent analogue containing a linker. Conjugation of the analogue containing the linker with peptides, which only are substrates for either prostate specific antigen (PSA) or prostate specific membrane antigen (PSMA) enabled design of prodrugs targeting a number of cancer diseases including prostate cancer (G115) and hepatocellular carcinoma (G202). Prodrug G202 has under the name of mipsagargin in phase II clinical trials shown promising properties against hepatocellular carcinoma. PMID:26429715

  2. Development of Beliefs about the Origins and Controllability of Dreams.

    ERIC Educational Resources Information Center

    Woolley, Jacqueline D.; Boerger, Elizabeth A.

    2002-01-01

    Three studies investigated development of beliefs about dreams among preschoolers, elementary school children, and adults. Results revealed significant changes between 3- and 5-years about the role of behavioral experiences and mental processes in generation of dream content. There was significant development in beliefs that dreams are not subject…

  3. Litter-of-origin trait effects on gilt development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The preweaning litter environment of gilts can affect subsequent development. In a recent experiment designed to test the effects of diet on gilt development, individual birth weights, immunocrits, sow parity, number weaned, and individual weaning weights were collected for gilts during the preweani...

  4. Notes on quantitative structure-property relationships (QSPR), part 3: density functions origin shift as a source of quantum QSPR algorithms in molecular spaces.

    PubMed

    Carbó-Dorca, Ramon

    2013-04-01

    A general algorithm implementing a useful variant of quantum quantitative structure-property relationships (QQSPR) theory is described. Based on quantum similarity framework and previous theoretical developments on the subject, the present QQSPR procedure relies on the possibility to perform geometrical origin shifts over molecular density function sets. In this way, molecular collections attached to known properties can be easily used over other quantum mechanically well-described molecular structures for the estimation of their unknown property values. The proposed procedure takes quantum mechanical expectation value as provider of causal relation background and overcomes the dimensionality paradox, which haunts classical descriptor space QSPR. Also, contrarily to classical procedures, which are also attached to heavy statistical gear, the present QQSPR approach might use a geometrical assessment only or just some simple statistical outline or both. From an applied point of view, several easily reachable computational levels can be set up. A Fortran 95 program: QQSPR-n is described with two versions, which might be downloaded from a dedicated web site. Various practical examples are provided, yielding excellent results. Finally, it is also shown that an equivalent molecular space classical QSPR formalism can be easily developed. PMID:23238931

  5. IVF and embryo transfer: historical origin and development.

    PubMed

    Biggers, John D

    2012-08-01

    IVF and embryo transfer for the treatment of human infertility has now resulted in the birth of over 4 million babies. The technique did not arise as a quantum event but was built on the efforts of many earlier workers in the fields of reproductive endocrinology and development. One should remember the famous saying of Isaac Newton: 'If I have seen further than most, it is because I have stood on the shoulder's of giants'. Ethical and moral issues have always arisen when investigators study early mammalian development, particularly human development. This paper documents these earlier studies and also draws attention to the ethical and moral arguments that inevitably arose.

  6. IVF and embryo transfer: historical origin and development.

    PubMed

    Biggers, John D

    2012-08-01

    IVF and embryo transfer for the treatment of human infertility has now resulted in the birth of over 4 million babies. The technique did not arise as a quantum event but was built on the efforts of many earlier workers in the fields of reproductive endocrinology and development. One should remember the famous saying of Isaac Newton: 'If I have seen further than most, it is because I have stood on the shoulder's of giants'. Ethical and moral issues have always arisen when investigators study early mammalian development, particularly human development. This paper documents these earlier studies and also draws attention to the ethical and moral arguments that inevitably arose. PMID:22695311

  7. The development of a simplified epithelial tissue phantom for the evaluation of an autofluorescence mitigation algorithm

    NASA Astrophysics Data System (ADS)

    Hou, Vivian W.; Yang, Chenying; Nelson, Leonard Y.; Seibel, Eric J.

    2014-03-01

    Previously we developed an ultrathin, flexible, multimodal scanning fiber endoscope (SFE) for concurrent white light and fluorescence imaging. Autofluorescence (AF) arising from endogenous fluorophores (primarily collagen in the esophagus) act as major confounders in fluorescence-aided detection. To address the issue of AF, a real-time mitigation algorithm was developed and has been show to successfully remove AF during SFE imaging. To test our algorithm, we previously developed flexible, color-matched, synthetic phantoms featuring a homogenous distribution of collagen. In order to more rigorously test the AF mitigation algorithm, a phantom that better mimicked the in-vivo distribution of collagen in tissue was developed.

  8. Extended precision data types for the development of the original computer aided engineering applications

    NASA Astrophysics Data System (ADS)

    Pescaru, A.; Oanta, E.; Axinte, T.; Dascalescu, A.-D.

    2015-11-01

    Computer aided engineering is based on models of the phenomena which are expressed as algorithms. The implementations of the algorithms are usually software applications which are processing a large volume of numerical data, regardless the size of the input data. In this way, the finite element method applications used to have an input data generator which was creating the entire volume of geometrical data, starting from the initial geometrical information and the parameters stored in the input data file. Moreover, there were several data processing stages, such as: renumbering of the nodes meant to minimize the size of the band length of the system of equations to be solved, computation of the equivalent nodal forces, computation of the element stiffness matrix, assemblation of system of equations, solving the system of equations, computation of the secondary variables. The modern software application use pre-processing and post-processing programs to easily handle the information. Beside this example, CAE applications use various stages of complex computation, being very interesting the accuracy of the final results. Along time, the development of CAE applications was a constant concern of the authors and the accuracy of the results was a very important target. The paper presents the various computing techniques which were imagined and implemented in the resulting applications: finite element method programs, finite difference element method programs, applied general numerical methods applications, data generators, graphical applications, experimental data reduction programs. In this context, the use of the extended precision data types was one of the solutions, the limitations being imposed by the size of the memory which may be allocated. To avoid the memory-related problems the data was stored in files. To minimize the execution time, part of the file was accessed using the dynamic memory allocation facilities. One of the most important consequences of the

  9. Motion Cueing Algorithm Development: New Motion Cueing Program Implementation and Tuning

    NASA Technical Reports Server (NTRS)

    Houck, Jacob A. (Technical Monitor); Telban, Robert J.; Cardullo, Frank M.; Kelly, Lon C.

    2005-01-01

    A computer program has been developed for the purpose of driving the NASA Langley Research Center Visual Motion Simulator (VMS). This program includes two new motion cueing algorithms, the optimal algorithm and the nonlinear algorithm. A general description of the program is given along with a description and flowcharts for each cueing algorithm, and also descriptions and flowcharts for subroutines used with the algorithms. Common block variable listings and a program listing are also provided. The new cueing algorithms have a nonlinear gain algorithm implemented that scales each aircraft degree-of-freedom input with a third-order polynomial. A description of the nonlinear gain algorithm is given along with past tuning experience and procedures for tuning the gain coefficient sets for each degree-of-freedom to produce the desired piloted performance. This algorithm tuning will be needed when the nonlinear motion cueing algorithm is implemented on a new motion system in the Cockpit Motion Facility (CMF) at the NASA Langley Research Center.

  10. Motion Cueing Algorithm Development: Human-Centered Linear and Nonlinear Approaches

    NASA Technical Reports Server (NTRS)

    Houck, Jacob A. (Technical Monitor); Telban, Robert J.; Cardullo, Frank M.

    2005-01-01

    While the performance of flight simulator motion system hardware has advanced substantially, the development of the motion cueing algorithm, the software that transforms simulated aircraft dynamics into realizable motion commands, has not kept pace. Prior research identified viable features from two algorithms: the nonlinear "adaptive algorithm", and the "optimal algorithm" that incorporates human vestibular models. A novel approach to motion cueing, the "nonlinear algorithm" is introduced that combines features from both approaches. This algorithm is formulated by optimal control, and incorporates a new integrated perception model that includes both visual and vestibular sensation and the interaction between the stimuli. Using a time-varying control law, the matrix Riccati equation is updated in real time by a neurocomputing approach. Preliminary pilot testing resulted in the optimal algorithm incorporating a new otolith model, producing improved motion cues. The nonlinear algorithm vertical mode produced a motion cue with a time-varying washout, sustaining small cues for longer durations and washing out large cues more quickly compared to the optimal algorithm. The inclusion of the integrated perception model improved the responses to longitudinal and lateral cues. False cues observed with the NASA adaptive algorithm were absent. The neurocomputing approach was crucial in that the number of presentations of an input vector could be reduced to meet the real time requirement without degrading the quality of the motion cues.

  11. Design requirements and development of an airborne descent path definition algorithm for time navigation

    NASA Technical Reports Server (NTRS)

    Izumi, K. H.; Thompson, J. L.; Groce, J. L.; Schwab, R. W.

    1986-01-01

    The design requirements for a 4D path definition algorithm are described. These requirements were developed for the NASA ATOPS as an extension of the Local Flow Management/Profile Descent algorithm. They specify the processing flow, functional and data architectures, and system input requirements, and recommended the addition of a broad path revision (reinitialization) function capability. The document also summarizes algorithm design enhancements and the implementation status of the algorithm on an in-house PDP-11/70 computer. Finally, the requirements for the pilot-computer interfaces, the lateral path processor, and guidance and steering function are described.

  12. Community Psychology in South Africa: Origins, Developments, and Manifestations

    ERIC Educational Resources Information Center

    Seedat, Mohamed; Lazarus, Sandy

    2011-01-01

    This article represents a South African contribution to the growing international body of knowledge on histories of community psychology. We trace the early antecedents of social-community psychology interventions and describe the social forces and academic influences that provided the impetus for the emergence and development of community…

  13. Online Library Tutorials at Antelope Valley College: Origin and Development

    ERIC Educational Resources Information Center

    Burrell, Carolyn; Lee, Scott

    2005-01-01

    Antelope Valley College Library has provided online library instruction tutorials for students since 2000. These tutorials were developed in three phases during the last five years. This article describes the evolution of the tutorials including how to create a web based tutorial and accompanying interactive quiz. Hardware and software…

  14. Update on Development of Mesh Generation Algorithms in MeshKit

    SciTech Connect

    Jain, Rajeev; Vanderzee, Evan; Mahadevan, Vijay

    2015-09-30

    MeshKit uses a graph-based design for coding all its meshing algorithms, which includes the Reactor Geometry (and mesh) Generation (RGG) algorithms. This report highlights the developmental updates of all the algorithms, results and future work. Parallel versions of algorithms, documentation and performance results are reported. RGG GUI design was updated to incorporate new features requested by the users; boundary layer generation and parallel RGG support were added to the GUI. Key contributions to the release, upgrade and maintenance of other SIGMA1 libraries (CGM and MOAB) were made. Several fundamental meshing algorithms for creating a robust parallel meshing pipeline in MeshKit are under development. Results and current status of automated, open-source and high quality nuclear reactor assembly mesh generation algorithms such as trimesher, quadmesher, interval matching and multi-sweeper are reported.

  15. Developments in Human Centered Cueing Algorithms for Control of Flight Simulator Motion Systems

    NASA Technical Reports Server (NTRS)

    Houck, Jacob A.; Telban, Robert J.; Cardullo, Frank M.

    1997-01-01

    The authors conducted further research with cueing algorithms for control of flight simulator motion systems. A variation of the so-called optimal algorithm was formulated using simulated aircraft angular velocity input as a basis. Models of the human vestibular sensation system, i.e. the semicircular canals and otoliths, are incorporated within the algorithm. Comparisons of angular velocity cueing responses showed a significant improvement over a formulation using angular acceleration input. Results also compared favorably with the coordinated adaptive washout algorithm, yielding similar results for angular velocity cues while eliminating false cues and reducing the tilt rate for longitudinal cues. These results were confirmed in piloted tests on the current motion system at NASA-Langley, the Visual Motion Simulator (VMS). Proposed future developments by the authors in cueing algorithms are revealed. The new motion system, the Cockpit Motion Facility (CMF), where the final evaluation of the cueing algorithms will be conducted, is also described.

  16. Evaluating Knowledge Structure-Based Adaptive Testing Algorithms and System Development

    ERIC Educational Resources Information Center

    Wu, Huey-Min; Kuo, Bor-Chen; Yang, Jinn-Min

    2012-01-01

    In recent years, many computerized test systems have been developed for diagnosing students' learning profiles. Nevertheless, it remains a challenging issue to find an adaptive testing algorithm to both shorten testing time and precisely diagnose the knowledge status of students. In order to find a suitable algorithm, four adaptive testing…

  17. Clustering algorithm evaluation and the development of a replacement for procedure 1. [for crop inventories

    NASA Technical Reports Server (NTRS)

    Lennington, R. K.; Johnson, J. K.

    1979-01-01

    An efficient procedure which clusters data using a completely unsupervised clustering algorithm and then uses labeled pixels to label the resulting clusters or perform a stratified estimate using the clusters as strata is developed. Three clustering algorithms, CLASSY, AMOEBA, and ISOCLS, are compared for efficiency. Three stratified estimation schemes and three labeling schemes are also considered and compared.

  18. Geologist's Field Assistant: Developing Image and Spectral Analyses Algorithms for Remote Science Exploration

    NASA Astrophysics Data System (ADS)

    Gulick, V. C.; Morris, R. L.; Bishop, J.; Gazis, P.; Alena, R.; Sierhuis, M.

    2002-03-01

    We are developing science analyses algorithms to interface with a Geologist's Field Assistant device to allow robotic or human remote explorers to better sense their surroundings during limited surface excursions. Our algorithms will interpret spectral and imaging data obtained by various sensors.

  19. Editorial Commentary: The Importance of Developing an Algorithm When Diagnosing Hip Pain.

    PubMed

    Coleman, Struan H

    2016-08-01

    The differential diagnosis of groin pain is broad and complex. Therefore, it is essential to develop an algorithm when differentiating the hip as a cause of groin pain from other sources. Selective injections in and around the hip can be helpful when making the diagnosis but are only one part of the algorithm.

  20. Development of Online Cognitive and Algorithm Tests as Assessment Tools in Introductory Computer Science Courses

    ERIC Educational Resources Information Center

    Avancena, Aimee Theresa; Nishihara, Akinori; Vergara, John Paul

    2012-01-01

    This paper presents the online cognitive and algorithm tests, which were developed in order to determine if certain cognitive factors and fundamental algorithms correlate with the performance of students in their introductory computer science course. The tests were implemented among Management Information Systems majors from the Philippines and…

  1. Development of a Behavioural Algorithm for Autonomous Spacecraft

    NASA Astrophysics Data System (ADS)

    Radice, G.

    manner with the environment through the use of sensors and actuators. As such, there is little computational effort required to implement such an approach, which is clearly of great benefit for limited micro-satellites. Rather than using complex world models, which have to be updated, the agent is allowed to exploit the dynamics of its environment for cues as to appropriate actions to take to achieve mission goals. The particular artificial agent implementation used here has been borrowed from studies of biological systems, where it has been used successfully to provide models of motivation and opportunistic behaviour. The so called "cue-deficit" action selection algorithm considers the micro-spacecraft to be a non linear dynamical system with a number of observable states. Using optimal control theory rules are derived which determine which of a finite repertoire of behaviours the satellite should select and perform. It will also be shown that in the event of hardware failures the algorithm will resequence the spacecraft actions to ensure survival while still meeting the mission goals, albeit in a degraded manner.

  2. Motor Development in Canadian Infants of Asian and European Ethnic Origins

    ERIC Educational Resources Information Center

    Mayson, Tanja A.; Backman, Catherine L.; Harris, Susan R.; Hayes, Virginia E.

    2009-01-01

    Ethnic origin is one factor that may influence the rate or sequence of infant motor development, interpretation of screening test results, and decisions regarding early intervention. The primary purpose of this study is to compare motor development screening test scores from infants of Asian and European ethnic origins. Using a cross-sectional…

  3. The origin and development of a concept: the information society.

    PubMed Central

    Crawford, S

    1983-01-01

    The constructs that underlie a discipline are complex and often times uncertain. It is argued that the ways in which we perceive and conceptualize are influenced by our habits of mind and our view of the world. This paper traces the concept of the "Information Society" from its inception in the discipline of economics through its development and its subsequent diffusion to the field of information science. PMID:6652297

  4. Dysthymia and cyclothymia: historical origins and contemporary development.

    PubMed

    Brieger, P; Marneros, A

    1997-09-01

    The aim of this article is to review and put in their historical context today's data, methodologies and concepts concerning subaffective disorders. The historic roots of dysthymic and cyclothymic disorders--part of the subaffective spectrum--are essentially Greek, but the first use of the word 'dysthymia' in psychiatry was by C.F. Flemming in 1844. E. Hecker introduced the term 'cyclothymia' in 1877. K.L. Kahlbaum (1882) further developed the concepts of hyperthymia, cyclothymia and dysthymia--with possible subthreshold symptomatology--in 1882. After Kraepelin's rubric of 'manic-depressive insanity', the term 'dysthymia' was widely forgotten, and 'cyclothymia' became ill defined. Nowadays the latter term is used in three, partially contradictory, senses: (1) a synonym for bipolar disorder (K. Schneider), (2) a temperament (E. Kretschmer) and (3) a subaffective disorder (DSM-IV, ICD-10). A renaissance of subaffective disorders began with the development of DSM-III. Therapeutically important research has focused on dysthymic disorder and its relationship to major depressive disorder, while cyclothymic disorder is relatively neglected; nonetheless, operationalized as a subaffective dimension or temperament, cyclothymia appears to be a likely precursor or ingredient of the construct of bipolar II disorder.

  5. Origins and early development of human body knowledge.

    PubMed

    Slaughter, Virginia; Heron, Michelle

    2004-01-01

    As a knowable object, the human body is highly complex. Evidence from several converging lines of research, including psychological studies, neuroimaging and clinical neuropsychology, indicates that human body knowledge is widely distributed in the adult brain, and is instantiated in at least three partially independent levels of representation. Sensorimotor body knowledge is responsible for on-line control and movement of one's own body and may also contribute to the perception of others' moving bodies; visuo-spatial body knowledge specifies detailed structural descriptions of the spatial attributes of the human body; and lexical-semantic body knowledge contains language-based knowledge about the human body. In the first chapter of this Monograph, we outline the evidence for these three hypothesized levels of human body knowledge, then review relevant literature on infants' and young children's human body knowledge in terms of the three-level framework. In Chapters II and III, we report two complimentary series of studies that specifically investigate the emergence of visuo-spatial body knowledge in infancy. Our technique is to compare infants'responses to typical and scrambled human bodies, in order to evaluate when and how infants acquire knowledge about the canonical spatial layout of the human body. Data from a series of visual habituation studies indicate that infants first discriminate scrambled from typical human body picture sat 15 to 18 months of age. Data from object examination studies similarly indicate that infants are sensitive to violations of three-dimensional human body stimuli starting at 15-18 months of age. The overall pattern of data supports several conclusions about the early development of human body knowledge: (a) detailed visuo-spatial knowledge about the human body is first evident in the second year of life, (b) visuo-spatial knowledge of human faces and human bodies are at least partially independent in infancy and (c) infants' initial

  6. Origins and early development of human body knowledge.

    PubMed

    Slaughter, Virginia; Heron, Michelle

    2004-01-01

    As a knowable object, the human body is highly complex. Evidence from several converging lines of research, including psychological studies, neuroimaging and clinical neuropsychology, indicates that human body knowledge is widely distributed in the adult brain, and is instantiated in at least three partially independent levels of representation. Sensorimotor body knowledge is responsible for on-line control and movement of one's own body and may also contribute to the perception of others' moving bodies; visuo-spatial body knowledge specifies detailed structural descriptions of the spatial attributes of the human body; and lexical-semantic body knowledge contains language-based knowledge about the human body. In the first chapter of this Monograph, we outline the evidence for these three hypothesized levels of human body knowledge, then review relevant literature on infants' and young children's human body knowledge in terms of the three-level framework. In Chapters II and III, we report two complimentary series of studies that specifically investigate the emergence of visuo-spatial body knowledge in infancy. Our technique is to compare infants'responses to typical and scrambled human bodies, in order to evaluate when and how infants acquire knowledge about the canonical spatial layout of the human body. Data from a series of visual habituation studies indicate that infants first discriminate scrambled from typical human body picture sat 15 to 18 months of age. Data from object examination studies similarly indicate that infants are sensitive to violations of three-dimensional human body stimuli starting at 15-18 months of age. The overall pattern of data supports several conclusions about the early development of human body knowledge: (a) detailed visuo-spatial knowledge about the human body is first evident in the second year of life, (b) visuo-spatial knowledge of human faces and human bodies are at least partially independent in infancy and (c) infants' initial

  7. An organismal perspective on C. intestinalis development, origins and diversification

    PubMed Central

    Kourakis, Matthew J; Smith, William C

    2015-01-01

    The ascidian Ciona intestinalis, commonly known as a ‘sea squirt’, has become an important model for embryological studies, offering a simple blueprint for chordate development. As a model organism, it offers the following: a small, compact genome; a free swimming larva with only about 2600 cells; and an embryogenesis that unfolds according to a predictable program of cell division. Moreover, recent phylogenies reveal that C. intestinalis occupies a privileged branch in the tree of life: it is our nearest invertebrate relative. Here, we provide an organismal perspective of C. intestinalis, highlighting aspects of its life history and habitat—from its brief journey as a larva to its radical metamorphosis into adult form—and relate these features to its utility as a laboratory model. DOI: http://dx.doi.org/10.7554/eLife.06024.001 PMID:25807088

  8. Benign myoepithelioma of the breast: origin and development.

    PubMed

    Hikino, Hajime; Nagaoka, Saburo; Miura, Hiroshi; Kurosumi, Masafumi

    2009-06-01

    A case of benign myoepithelioma of the breast in a 55-year-old woman is described. The tumor was a well-circumscribed solid mass, measuring 13 x 12 mm. Histopathology indicated that the tumor was composed of entirely myoepithelial cells, which was confirmed by immunoreactivity to calponin and S-100. There was no ductal differentiation in the tumor, and staining for pan-cytokeratin and epithelial membrane antigen was weak and negative, respectively. Although the biological behavior of the tumor remains to be ascertained, the tumor was considered to be myoepithelioma with benign features due to mild nuclear pleomorphism, sparse mitotic figures, low Ki-67 labeling index and low S-phase fraction. Diagnostic confusion between benign myoepithelioma and other myoepithelial-rich cell tumors is possible. Considering the classification of myoepithelial tumor in the salivary glands, benign myoepithelioma of the breast may possess a different development process from adenomyoepithelioma.

  9. Origin and development of the germ line in sea stars.

    PubMed

    Wessel, Gary M; Fresques, Tara; Kiyomoto, Masato; Yajima, Mamiko; Zazueta, Vanesa

    2014-05-01

    This review summarizes and integrates our current understanding of how sea stars make gametes. Although little is known of the mechanism of germ line formation in these animals, recent results point to specific cells and to cohorts of molecules in the embryos and larvae that may lay the ground work for future research efforts. A coelomic outpocketing forms in the posterior of the gut in larvae, referred to as the posterior enterocoel (PE), that when removed, significantly reduces the number of germ cell later in larval growth. This same PE structure also selectively accumulates several germ-line associated factors-vasa, nanos, piwi-and excludes factors involved in somatic cell fate. Since its formation is relatively late in development, these germ cells may form by inductive mechanisms. When integrated into the morphological observations of germ cells and gonad development in larvae, juveniles, and adults, the field of germ line determination appears to have a good model system to study inductive germ line determination to complement the recent work on the molecular mechanisms in mice. We hope this review will also guide investigators interested in germ line determination and regulation of the germ line into how these animals can help in this research field. The review is not intended to be comprehensive-sea star reproduction has been studied for over 100 years and many reviews are comprehensive in their coverage of, for example, seasonal growth of the gonads in response to light, nutrient, and temperature. Rather the intent of this review is to help the reader focus on new experimental results attached to the historical underpinnings of how the germ cell functions in sea stars with particular emphasis to clarify the important areas of priority for future research.

  10. Algorithm and simulation development in support of response strategies for contamination events in air and water systems.

    SciTech Connect

    Waanders, Bart Van Bloemen

    2006-01-01

    Chemical/Biological/Radiological (CBR) contamination events pose a considerable threat to our nation's infrastructure, especially in large internal facilities, external flows, and water distribution systems. Because physical security can only be enforced to a limited degree, deployment of early warning systems is being considered. However to achieve reliable and efficient functionality, several complex questions must be answered: (1) where should sensors be placed, (2) how can sparse sensor information be efficiently used to determine the location of the original intrusion, (3) what are the model and data uncertainties, (4) how should these uncertainties be handled, and (5) how can our algorithms and forward simulations be sufficiently improved to achieve real time performance? This report presents the results of a three year algorithmic and application development to support the identification, mitigation, and risk assessment of CBR contamination events. The main thrust of this investigation was to develop (1) computationally efficient algorithms for strategically placing sensors, (2) identification process of contamination events by using sparse observations, (3) characterization of uncertainty through developing accurate demands forecasts and through investigating uncertain simulation model parameters, (4) risk assessment capabilities, and (5) reduced order modeling methods. The development effort was focused on water distribution systems, large internal facilities, and outdoor areas.

  11. Parent-of-Origin DNA Methylation Dynamics during Mouse Development.

    PubMed

    Stelzer, Yonatan; Wu, Hao; Song, Yuelin; Shivalila, Chikdu S; Markoulaki, Styliani; Jaenisch, Rudolf

    2016-09-20

    Parent-specific differentially methylated regions (DMRs) are established during gametogenesis and regulate parent-specific expression of imprinted genes. Monoallelic expression of imprinted genes is essential for development, suggesting that imprints are faithfully maintained in embryos and adults. To test this hypothesis, we targeted a reporter for genomic methylation to the imprinted Dlk1-Dio3 intergenic DMR (IG-DMR) to assess the methylation of both parental alleles at single-cell resolution. Biallelic gain or loss of IG-DMR methylation occurred in a small fraction of mouse embryonic stem cells, significantly affecting developmental potency. Mice carrying the reporter in either parental allele showed striking parent-specific changes in IG-DMR methylation, causing substantial and consistent tissue- and cell-type-dependent signatures in embryos and postnatal animals. Furthermore, dynamics in DNA methylation persisted during adult neurogenesis, resulting in inter-individual diversity. This substantial cell-cell DNA methylation heterogeneity implies that dynamic DNA methylation variations in the adult may be of functional importance. PMID:27653683

  12. AeroADL: applying the integration of the Suomi-NPP science algorithms with the Algorithm Development Library to the calibration and validation task

    NASA Astrophysics Data System (ADS)

    Houchin, J. S.

    2014-09-01

    A common problem for the off-line validation of the calibration algorithms and algorithm coefficients is being able to run science data through the exact same software used for on-line calibration of that data. The Joint Polar Satellite System (JPSS) program solved part of this problem by making the Algorithm Development Library (ADL) available, which allows the operational algorithm code to be compiled and run on a desktop Linux workstation using flat file input and output. However, this solved only part of the problem, as the toolkit and methods to initiate the processing of data through the algorithms were geared specifically toward the algorithm developer, not the calibration analyst. In algorithm development mode, a limited number of sets of test data are staged for the algorithm once, and then run through the algorithm over and over as the software is developed and debugged. In calibration analyst mode, we are continually running new data sets through the algorithm, which requires significant effort to stage each of those data sets for the algorithm without additional tools. AeroADL solves this second problem by providing a set of scripts that wrap the ADL tools, providing both efficient means to stage and process an input data set, to override static calibration coefficient look-up-tables (LUT) with experimental versions of those tables, and to manage a library containing multiple versions of each of the static LUT files in such a way that the correct set of LUTs required for each algorithm are automatically provided to the algorithm without analyst effort. Using AeroADL, The Aerospace Corporation's analyst team has demonstrated the ability to quickly and efficiently perform analysis tasks for both the VIIRS and OMPS sensors with minimal training on the software tools.

  13. Development of new flux splitting schemes. [computational fluid dynamics algorithms

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing; Steffen, Christopher J., Jr.

    1992-01-01

    Maximizing both accuracy and efficiency has been the primary objective in designing a numerical algorithm for computational fluid dynamics (CFD). This is especially important for solutions of complex three dimensional systems of Navier-Stokes equations which often include turbulence modeling and chemistry effects. Recently, upwind schemes have been well received for their capability in resolving discontinuities. With this in mind, presented are two new flux splitting techniques for upwind differencing. The first method is based on High-Order Polynomial Expansions (HOPE) of the mass flux vector. The second new flux splitting is based on the Advection Upwind Splitting Method (AUSM). The calculation of the hypersonic conical flow demonstrates the accuracy of the splitting in resolving the flow in the presence of strong gradients. A second series of tests involving the two dimensional inviscid flow over a NACA 0012 airfoil demonstrates the ability of the AUSM to resolve the shock discontinuity at transonic speed. A third case calculates a series of supersonic flows over a circular cylinder. Finally, the fourth case deals with tests of a two dimensional shock wave/boundary layer interaction.

  14. Reflections on "Multiplication as Original Sin": The Implications of Using a Case to Help Preservice Teachers Understand Invented Algorithms

    ERIC Educational Resources Information Center

    Harkness, Shelly Sheats; Thomas, Jonathan

    2008-01-01

    This article describes the use of a case report, Multiplication as original sin (Corwin, R. B. (1989). "Multiplication as original sin." "Journal of Mathematical Behavior, 8", 223-225), as an assignment in a mathematics course for preservice elementary teachers. In this case study, Corwin described her experience as a 6th grader when she revealed…

  15. Swedish Upper Secondary Students' Views of the Origin and Development of the Universe

    ERIC Educational Resources Information Center

    Hansson, Lena; Redfors, Andreas

    2006-01-01

    The article is addressing how students reason about the origin and development of the universe. Students' own views as well as their descriptions of physical models are analysed. Data consists of written surveys, and interviews of a subset of the students. Most of the students relate to the Big Bang model when describing the origin of the…

  16. [Herbal textual research on origin and development of traditional Chinese medicine "duhuo" and "qianghuo"].

    PubMed

    Shan, Feng; Yuan, Yuan; Hao, Jin-Da; Huang, Lu-Qi

    2014-09-01

    To clarify the origin and development of the traditional Chinese medicine "Duhuo" and "Qianghuo" with medicinal literatures. Medical literatures of past dynasties were analysed and combined with the modern material. The "Duhuo" in Herbal writing Shen Nong Ben Cao Jing include traditional Chinese medicine "Duhuo" and "Qianghuo", "Qianghuo" was separated from "Duhuo" due to the distinguish of clinical application. The origin of "Qianghuo" is Notopterygium incisum and N. forbesii, However, The origin of "Duhuo" is very complex, Angelica pubescens f. biserrata as authentic "Duhuo" was used from Song Dynasty. "Qianghuo" was originated from "Duhuo".

  17. Development of an automatic identification algorithm for antibiogram analysis.

    PubMed

    Costa, Luan F R; da Silva, Eduardo S; Noronha, Victor T; Vaz-Moreira, Ivone; Nunes, Olga C; Andrade, Marcelino M de

    2015-12-01

    Routinely, diagnostic and microbiology laboratories perform antibiogram analysis which can present some difficulties leading to misreadings and intra and inter-reader deviations. An Automatic Identification Algorithm (AIA) has been proposed as a solution to overcome some issues associated with the disc diffusion method, which is the main goal of this work. AIA allows automatic scanning of inhibition zones obtained by antibiograms. More than 60 environmental isolates were tested using susceptibility tests which were performed for 12 different antibiotics for a total of 756 readings. Plate images were acquired and classified as standard or oddity. The inhibition zones were measured using the AIA and results were compared with reference method (human reading), using weighted kappa index and statistical analysis to evaluate, respectively, inter-reader agreement and correlation between AIA-based and human-based reading. Agreements were observed in 88% cases and 89% of the tests showed no difference or a <4mm difference between AIA and human analysis, exhibiting a correlation index of 0.85 for all images, 0.90 for standards and 0.80 for oddities with no significant difference between automatic and manual method. AIA resolved some reading problems such as overlapping inhibition zones, imperfect microorganism seeding, non-homogeneity of the circumference, partial action of the antimicrobial, and formation of a second halo of inhibition. Furthermore, AIA proved to overcome some of the limitations observed in other automatic methods. Therefore, AIA may be a practical tool for automated reading of antibiograms in diagnostic and microbiology laboratories. PMID:26513468

  18. Characterizing interplanetary shocks for development and optimization of an automated solar wind shock detection algorithm

    NASA Astrophysics Data System (ADS)

    Cash, M. D.; Wrobel, J. S.; Cosentino, K. C.; Reinard, A. A.

    2014-06-01

    Human evaluation of solar wind data for interplanetary (IP) shock identification relies on both heuristics and pattern recognition, with the former lending itself to algorithmic representation and automation. Such detection algorithms can potentially alert forecasters of approaching shocks, providing increased warning of subsequent geomagnetic storms. However, capturing shocks with an algorithmic treatment alone is challenging, as past and present work demonstrates. We present a statistical analysis of 209 IP shocks observed at L1, and we use this information to optimize a set of shock identification criteria for use with an automated solar wind shock detection algorithm. In order to specify ranges for the threshold values used in our algorithm, we quantify discontinuities in the solar wind density, velocity, temperature, and magnetic field magnitude by analyzing 8 years of IP shocks detected by the SWEPAM and MAG instruments aboard the ACE spacecraft. Although automatic shock detection algorithms have previously been developed, in this paper we conduct a methodical optimization to refine shock identification criteria and present the optimal performance of this and similar approaches. We compute forecast skill scores for over 10,000 permutations of our shock detection criteria in order to identify the set of threshold values that yield optimal forecast skill scores. We then compare our results to previous automatic shock detection algorithms using a standard data set, and our optimized algorithm shows improvements in the reliability of automated shock detection.

  19. Analysis and Classification of Stride Patterns Associated with Children Development Using Gait Signal Dynamics Parameters and Ensemble Learning Algorithms.

    PubMed

    Wu, Meihong; Liao, Lifang; Luo, Xin; Ye, Xiaoquan; Yao, Yuchen; Chen, Pinnan; Shi, Lei; Huang, Hui; Wu, Yunfeng

    2016-01-01

    Measuring stride variability and dynamics in children is useful for the quantitative study of gait maturation and neuromotor development in childhood and adolescence. In this paper, we computed the sample entropy (SampEn) and average stride interval (ASI) parameters to quantify the stride series of 50 gender-matched children participants in three age groups. We also normalized the SampEn and ASI values by leg length and body mass for each participant, respectively. Results show that the original and normalized SampEn values consistently decrease over the significance level of the Mann-Whitney U test (p < 0.01) in children of 3-14 years old, which indicates the stride irregularity has been significantly ameliorated with the body growth. The original and normalized ASI values are also significantly changing when comparing between any two groups of young (aged 3-5 years), middle (aged 6-8 years), and elder (aged 10-14 years) children. Such results suggest that healthy children may better modulate their gait cadence rhythm with the development of their musculoskeletal and neurological systems. In addition, the AdaBoost.M2 and Bagging algorithms were used to effectively distinguish the children's gait patterns. These ensemble learning algorithms both provided excellent gait classification results in terms of overall accuracy (≥90%), recall (≥0.8), and precision (≥0.8077). PMID:27034952

  20. Analysis and Classification of Stride Patterns Associated with Children Development Using Gait Signal Dynamics Parameters and Ensemble Learning Algorithms

    PubMed Central

    Wu, Meihong; Liao, Lifang; Luo, Xin; Ye, Xiaoquan; Yao, Yuchen; Chen, Pinnan; Shi, Lei; Huang, Hui

    2016-01-01

    Measuring stride variability and dynamics in children is useful for the quantitative study of gait maturation and neuromotor development in childhood and adolescence. In this paper, we computed the sample entropy (SampEn) and average stride interval (ASI) parameters to quantify the stride series of 50 gender-matched children participants in three age groups. We also normalized the SampEn and ASI values by leg length and body mass for each participant, respectively. Results show that the original and normalized SampEn values consistently decrease over the significance level of the Mann-Whitney U test (p < 0.01) in children of 3–14 years old, which indicates the stride irregularity has been significantly ameliorated with the body growth. The original and normalized ASI values are also significantly changing when comparing between any two groups of young (aged 3–5 years), middle (aged 6–8 years), and elder (aged 10–14 years) children. Such results suggest that healthy children may better modulate their gait cadence rhythm with the development of their musculoskeletal and neurological systems. In addition, the AdaBoost.M2 and Bagging algorithms were used to effectively distinguish the children's gait patterns. These ensemble learning algorithms both provided excellent gait classification results in terms of overall accuracy (≥90%), recall (≥0.8), and precision (≥0.8077). PMID:27034952

  1. METHOD DEVELOPMENT FOR THE DETERMINATION OF FORMALDEHYDE IN SAMPLES OF ENVIRONMENTAL ORIGIN

    EPA Science Inventory

    An analytical method was developed for the determination of formaldehyde in samples of environmental origin. After a review of the current literature, five candidate methods involving chemical derivatization were chosen for evaluation. The five derivatization reagents studied wer...

  2. The development of an algebraic multigrid algorithm for symmetric positive definite linear systems

    SciTech Connect

    Vanek, P.; Mandel, J.; Brezina, M.

    1996-12-31

    An algebraic multigrid algorithm for symmetric, positive definite linear systems is developed based on the concept of prolongation by smoothed aggregation. Coarse levels are generated automatically. We present a set of requirements motivated heuristically by a convergence theory. The algorithm then attempts to satisfy the requirements. Input to the method are the coefficient matrix and zero energy modes, which are determined from nodal coordinates and knowledge of the differential equation. Efficiency of the resulting algorithm is demonstrated by computational results on real world problems from solid elasticity, plate blending, and shells.

  3. Deciphering the Minimal Algorithm for Development and Information-genesis

    NASA Astrophysics Data System (ADS)

    Li, Zhiyuan; Tang, Chao; Li, Hao

    During development, cells with identical genomes acquires different fates in a highly organized manner. In order to decipher the principles underlining development, we used C.elegans as the model organism. Based on a large set of microscopy imaging, we first constructed a ``standard worm'' in silico: from the single zygotic cell to about 500 cell stage, the lineage, position, cell-cell contact and gene expression dynamics are quantified for each cell in order to investigate principles underlining these intensive data. Next, we reverse-engineered the possible gene-gene/cell-cell interaction rules that are capable of running a dynamic model recapitulating the early fate decisions during C.elegans development. we further formulized the C.elegans embryogenesis in the language of information genesis. Analysis towards data and model uncovered the global landscape of development in the cell fate space, suggested possible gene regulatory architectures and cell signaling processes, revealed diversity and robustness as the essential trade-offs in development, and demonstrated general strategies in building multicellular organisms.

  4. MODIS algorithm development and data visualization using ACTS

    NASA Technical Reports Server (NTRS)

    Abbott, Mark R.

    1992-01-01

    The study of the Earth as a system will require the merger of scientific and data resources on a much larger scale than has been done in the past. New methods of scientific research, particularly in the development of geographically dispersed, interdisciplinary teams, are necessary if we are to understand the complexity of the Earth system. Even the planned satellite missions themselves, such as the Earth Observing System, will require much more interaction between researchers and engineers if they are to produce scientifically useful data products. A key component in these activities is the development of flexible, high bandwidth data networks that can be used to move large amounts of data as well as allow researchers to communicate in new ways, such as through video. The capabilities of the Advanced Communications Technology Satellite (ACTS) will allow the development of such networks. The Pathfinder global AVHRR data set and the upcoming SeaWiFS Earthprobe mission would serve as a testbed in which to develop the tools to share data and information among geographically distributed researchers. Our goal is to develop a 'Distributed Research Environment' that can be used as a model for scientific collaboration in the EOS era. The challenge is to unite the advances in telecommunications with the parallel advances in computing and networking.

  5. Development of HF radar inversion algorithm for spectrum estimation (HIAS)

    NASA Astrophysics Data System (ADS)

    Hisaki, Yukiharu

    2015-03-01

    A method for estimating ocean wave directional spectra using an HF (high-frequency) ocean radar was developed. This method represents the development of work conducted in previous studies. In the present method, ocean wave directional spectra are estimated on polar coordinates whose center is the radar position, while spectra are estimated on regular grids. This method can be applied to both single and multiple radar cases. The area for wave estimation is more flexible than that of the previous method. As the signal to noise (SN) ratios of Doppler spectra are critical for wave estimation, we develop a method to exclude low SN ratio Doppler spectra. The validity of the method is demonstrated by comparing results with in situ observed wave data that it would be impossible to estimate by the methods of other groups.

  6. The Development of FPGA-Based Pseudo-Iterative Clustering Algorithms

    NASA Astrophysics Data System (ADS)

    Drueke, Elizabeth; Fisher, Wade; Plucinski, Pawel

    2016-03-01

    The Large Hadron Collider (LHC) in Geneva, Switzerland, is set to undergo major upgrades in 2025 in the form of the High-Luminosity Large Hadron Collider (HL-LHC). In particular, several hardware upgrades are proposed to the ATLAS detector, one of the two general purpose detectors. These hardware upgrades include, but are not limited to, a new hardware-level clustering algorithm, to be performed by a field programmable gate array, or FPGA. In this study, we develop that clustering algorithm and compare the output to a Python-implemented topoclustering algorithm developed at the University of Oregon. Here, we present the agreement between the FPGA output and expected output, with particular attention to the time required by the FPGA to complete the algorithm and other limitations set by the FPGA itself.

  7. Development of practical multiband algorithms for estimating land-surface temperature from EOS/MODIS data

    NASA Technical Reports Server (NTRS)

    Dozier, J.; Wan, Z.

    1994-01-01

    A practical multiband, hierarchical algorithm for estimating land-surface temperature from NASA's future Earth Observing System (EOS) instruments Moderate Resolution Imaging Spectroradiometer (MODIS) and Advance Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is developed through comprehensive, accurate, radiative transfer simulations at moderate spectral steps of 1-5/cm for wide ranges of atmospheric and surface conditions. The algorithm will accept empirical or estimated information about the surface emissivity and reflectivity and the atmospheric temperature and water-vapor profiles. Ground-based and aircraft measurements are necessary to validate and improve the algorithm and to establish its quality. Its accuracy depends on the calibration accuracy of thermal infrared data, uncertainties in surface heterogeneity, and temperature-dependent atmospheric absorption coefficients. Better knowledge of land-surface spectral emissivities and more accurate coefficients for atmospheric molecular band absorption and water vapor continuum absorption are needed to develop global land-surface temperature algorithms accurate to 1-2 K.

  8. Development of a Computer-Aided-Design-Based Geometry and Mesh Movement Algorithm for Three-Dimensional Aerodynamic Shape Optimization

    NASA Astrophysics Data System (ADS)

    Truong, Anh Hoang

    This thesis focuses on the development of a Computer-Aided-Design (CAD)-based geometry parameterization method and a corresponding surface mesh movement algorithm suitable for three-dimensional aerodynamic shape optimization. The geometry parameterization method includes a geometry control tool to aid in the construction and manipulation of a CAD geometry through a vendor-neutral application interface, CAPRI. It automates the tedious part of the construction phase involving data entry and provides intuitive and effective design variables that allow for both the flexibility and the precision required to control the movement of the geometry. The surface mesh movement algorithm, on the other hand, transforms an initial structured surface mesh to fit the new geometry using a discrete representation of the new CAD surface provided by CAPRI. Using a unique mapping procedure, the algorithm not only preserves the characteristics of the original surface mesh, but also guarantees that the new mesh points are on the CAD geometry. The new surface mesh is then smoothed in the parametric space before it is transformed back into three-dimensional space. The procedure is efficient in that all the processing is done in the parametric space, incurring minimal computational cost. The geometry parameterization and mesh movement tools are integrated into a three-dimensional shape optimization framework, with a linear-elasticity volume-mesh movement algorithm, a Newton-Krylov flow solver for the Euler equations, and a gradient-based optimizer. The validity and accuracy of the CAD-based optimization algorithm are demonstrated through a number of verification and optimization cases.

  9. Millimeter-wave imaging radiometer data processing and development of water vapor retrieval algorithms

    NASA Technical Reports Server (NTRS)

    Chang, L. Aron

    1995-01-01

    This document describes the current status of Millimeter-wave Imaging Radiometer (MIR) data processing and the technical development of the first version of a water vapor retrieval algorithm. The algorithm is being used by NASA/GSFC Microwave Sensors Branch, Laboratory for Hydrospheric Processes. It is capable of a three dimensional mapping of moisture fields using microwave data from airborne sensor of MIR and spaceborne instrument of Special Sensor Microwave/T-2 (SSM/T-2).

  10. Applications of feature selection. [development of classification algorithms for LANDSAT data

    NASA Technical Reports Server (NTRS)

    Guseman, L. F., Jr.

    1976-01-01

    The use of satellite-acquired (LANDSAT) multispectral scanner (MSS) data to conduct an inventory of some crop of economic interest such as wheat over a large geographical area is considered in relation to the development of accurate and efficient algorithms for data classification. The dimension of the measurement space and the computational load for a classification algorithm is increased by the use of multitemporal measurements. Feature selection/combination techniques used to reduce the dimensionality of the problem are described.

  11. Development and validation of an automated operational modal analysis algorithm for vibration-based monitoring and tensile load estimation

    NASA Astrophysics Data System (ADS)

    Rainieri, Carlo; Fabbrocino, Giovanni

    2015-08-01

    In the last few decades large research efforts have been devoted to the development of methods for automated detection of damage and degradation phenomena at an early stage. Modal-based damage detection techniques are well-established methods, whose effectiveness for Level 1 (existence) and Level 2 (location) damage detection is demonstrated by several studies. The indirect estimation of tensile loads in cables and tie-rods is another attractive application of vibration measurements. It provides interesting opportunities for cheap and fast quality checks in the construction phase, as well as for safety evaluations and structural maintenance over the structure lifespan. However, the lack of automated modal identification and tracking procedures has been for long a relevant drawback to the extensive application of the above-mentioned techniques in the engineering practice. An increasing number of field applications of modal-based structural health and performance assessment are appearing after the development of several automated output-only modal identification procedures in the last few years. Nevertheless, additional efforts are still needed to enhance the robustness of automated modal identification algorithms, control the computational efforts and improve the reliability of modal parameter estimates (in particular, damping). This paper deals with an original algorithm for automated output-only modal parameter estimation. Particular emphasis is given to the extensive validation of the algorithm based on simulated and real datasets in view of continuous monitoring applications. The results point out that the algorithm is fairly robust and demonstrate its ability to provide accurate and precise estimates of the modal parameters, including damping ratios. As a result, it has been used to develop systems for vibration-based estimation of tensile loads in cables and tie-rods. Promising results have been achieved for non-destructive testing as well as continuous

  12. Development and application of unified algorithms for problems in computational science

    NASA Technical Reports Server (NTRS)

    Shankar, Vijaya; Chakravarthy, Sukumar

    1987-01-01

    A framework is presented for developing computationally unified numerical algorithms for solving nonlinear equations that arise in modeling various problems in mathematical physics. The concept of computational unification is an attempt to encompass efficient solution procedures for computing various nonlinear phenomena that may occur in a given problem. For example, in Computational Fluid Dynamics (CFD), a unified algorithm will be one that allows for solutions to subsonic (elliptic), transonic (mixed elliptic-hyperbolic), and supersonic (hyperbolic) flows for both steady and unsteady problems. The objectives are: development of superior unified algorithms emphasizing accuracy and efficiency aspects; development of codes based on selected algorithms leading to validation; application of mature codes to realistic problems; and extension/application of CFD-based algorithms to problems in other areas of mathematical physics. The ultimate objective is to achieve integration of multidisciplinary technologies to enhance synergism in the design process through computational simulation. Specific unified algorithms for a hierarchy of gas dynamics equations and their applications to two other areas: electromagnetic scattering, and laser-materials interaction accounting for melting.

  13. Ocean observations with EOS/MODIS: Algorithm development and post launch studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1995-01-01

    An investigation of the influence of stratospheric aerosol on the performance of the atmospheric correction algorithm was carried out. The results indicate how the performance of the algorithm is degraded if the stratospheric aerosol is ignored. Use of the MODIS 1380 nm band to effect a correction for stratospheric aerosols was also studied. The development of a multi-layer Monte Carlo radiative transfer code that includes polarization by molecular and aerosol scattering and wind-induced sea surface roughness has been completed. Comparison tests with an existing two-layer successive order of scattering code suggests that both codes are capable of producing top-of-atmosphere radiances with errors usually less than 0.1 percent. An initial set of simulations to study the effects of ignoring the polarization of the the ocean-atmosphere light field, in both the development of the atmospheric correction algorithm and the generation of the lookup tables used for operation of the algorithm, have been completed. An algorithm was developed that can be used to invert the radiance exiting the top and bottom of the atmosphere to yield the columnar optical properties of the atmospheric aerosol under clear sky conditions over the ocean, for aerosol optical thicknesses as large as 2. The algorithm is capable of retrievals with such large optical thicknesses because all significant orders of multiple scattering are included.

  14. Unified Framework for Development, Deployment and Robust Testing of Neuroimaging Algorithms

    PubMed Central

    Joshi, Alark; Scheinost, Dustin; Okuda, Hirohito; Belhachemi, Dominique; Murphy, Isabella; Staib, Lawrence H.; Papademetris, Xenophon

    2011-01-01

    Developing both graphical and command-line user interfaces for neuroimaging algorithms requires considerable effort. Neuroimaging algorithms can meet their potential only if they can be easily and frequently used by their intended users. Deployment of a large suite of such algorithms on multiple platforms requires consistency of user interface controls, consistent results across various platforms and thorough testing. We present the design and implementation of a novel object-oriented framework that allows for rapid development of complex image analysis algorithms with many reusable components and the ability to easily add graphical user interface controls. Our framework also allows for simplified yet robust nightly testing of the algorithms to ensure stability and cross platform interoperability. All of the functionality is encapsulated into a software object requiring no separate source code for user interfaces, testing or deployment. This formulation makes our framework ideal for developing novel, stable and easy-to-use algorithms for medical image analysis and computer assisted interventions. The framework has been both deployed at Yale and released for public use in the open source multi-platform image analysis software—BioImage Suite (bioimagesuite.org). PMID:21249532

  15. Development of Fast Algorithms Using Recursion, Nesting and Iterations for Computational Electromagnetics

    NASA Technical Reports Server (NTRS)

    Chew, W. C.; Song, J. M.; Lu, C. C.; Weedon, W. H.

    1995-01-01

    In the first phase of our work, we have concentrated on laying the foundation to develop fast algorithms, including the use of recursive structure like the recursive aggregate interaction matrix algorithm (RAIMA), the nested equivalence principle algorithm (NEPAL), the ray-propagation fast multipole algorithm (RPFMA), and the multi-level fast multipole algorithm (MLFMA). We have also investigated the use of curvilinear patches to build a basic method of moments code where these acceleration techniques can be used later. In the second phase, which is mainly reported on here, we have concentrated on implementing three-dimensional NEPAL on a massively parallel machine, the Connection Machine CM-5, and have been able to obtain some 3D scattering results. In order to understand the parallelization of codes on the Connection Machine, we have also studied the parallelization of 3D finite-difference time-domain (FDTD) code with PML material absorbing boundary condition (ABC). We found that simple algorithms like the FDTD with material ABC can be parallelized very well allowing us to solve within a minute a problem of over a million nodes. In addition, we have studied the use of the fast multipole method and the ray-propagation fast multipole algorithm to expedite matrix-vector multiplication in a conjugate-gradient solution to integral equations of scattering. We find that these methods are faster than LU decomposition for one incident angle, but are slower than LU decomposition when many incident angles are needed as in the monostatic RCS calculations.

  16. Developing NASA's VIIRS LST and Emissivity EDRs using a physics based Temperature Emissivity Separation (TES) algorithm

    NASA Astrophysics Data System (ADS)

    Islam, T.; Hulley, G. C.; Malakar, N.; Hook, S. J.

    2015-12-01

    Land Surface Temperature and Emissivity (LST&E) data are acknowledged as critical Environmental Data Records (EDRs) by the NASA Earth Science Division. The current operational LST EDR for the recently launched Suomi National Polar-orbiting Partnership's (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) payload utilizes a split-window algorithm that relies on previously-generated fixed emissivity dependent coefficients and does not produce a dynamically varying and multi-spectral land surface emissivity product. Furthermore, this algorithm deviates from its MODIS counterpart (MOD11) resulting in a discontinuity in the MODIS/VIIRS LST time series. This study presents an alternative physics based algorithm for generation of the NASA VIIRS LST&E EDR in order to provide continuity with its MODIS counterpart algorithm (MOD21). The algorithm, known as temperature emissivity separation (TES) algorithm, uses a fast radiative transfer model - Radiative Transfer for (A)TOVS (RTTOV) in combination with an emissivity calibration model to isolate the surface radiance contribution retrieving temperature and emissivity. Further, a new water-vapor scaling (WVS) method is developed and implemented to improve the atmospheric correction process within the TES system. An independent assessment of the VIIRS LST&E outputs is performed against in situ LST measurements and laboratory measured emissivity spectra samples over dedicated validation sites in the Southwest USA. Emissivity retrievals are also validated with the latest ASTER Global Emissivity Database Version 4 (GEDv4). An overview and current status of the algorithm as well as the validation results will be discussed.

  17. Battery algorithm verification and development using hardware-in-the-loop testing

    NASA Astrophysics Data System (ADS)

    He, Yongsheng; Liu, Wei; Koch, Brain J.

    Battery algorithms play a vital role in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), extended-range electric vehicles (EREVs), and electric vehicles (EVs). The energy management of hybrid and electric propulsion systems needs to rely on accurate information on the state of the battery in order to determine the optimal electric drive without abusing the battery. In this study, a cell-level hardware-in-the-loop (HIL) system is used to verify and develop state of charge (SOC) and power capability predictions of embedded battery algorithms for various vehicle applications. Two different batteries were selected as representative examples to illustrate the battery algorithm verification and development procedure. One is a lithium-ion battery with a conventional metal oxide cathode, which is a power battery for HEV applications. The other is a lithium-ion battery with an iron phosphate (LiFePO 4) cathode, which is an energy battery for applications in PHEVs, EREVs, and EVs. The battery cell HIL testing provided valuable data and critical guidance to evaluate the accuracy of the developed battery algorithms, to accelerate battery algorithm future development and improvement, and to reduce hybrid/electric vehicle system development time and costs.

  18. Advancements in the Development of an Operational Lightning Jump Algorithm for GOES-R GLM

    NASA Technical Reports Server (NTRS)

    Shultz, Chris; Petersen, Walter; Carey, Lawrence

    2011-01-01

    Rapid increases in total lightning have been shown to precede the manifestation of severe weather at the surface. These rapid increases have been termed lightning jumps, and are the current focus of algorithm development for the GOES-R Geostationary Lightning Mapper (GLM). Recent lightning jump algorithm work has focused on evaluation of algorithms in three additional regions of the country, as well as, markedly increasing the number of thunderstorms in order to evaluate the each algorithm s performance on a larger population of storms. Lightning characteristics of just over 600 thunderstorms have been studied over the past four years. The 2 lightning jump algorithm continues to show the most promise for an operational lightning jump algorithm, with a probability of detection of 82%, a false alarm rate of 35%, a critical success index of 57%, and a Heidke Skill Score of 0.73 on the entire population of thunderstorms. Average lead time for the 2 algorithm on all severe weather is 21.15 minutes, with a standard deviation of +/- 14.68 minutes. Looking at tornadoes alone, the average lead time is 18.71 minutes, with a standard deviation of +/-14.88 minutes. Moreover, removing the 2 lightning jumps that occur after a jump has been detected, and before severe weather is detected at the ground, the 2 lightning jump algorithm s false alarm rate drops from 35% to 21%. Cold season, low topped, and tropical environments cause problems for the 2 lightning jump algorithm, due to their relative dearth in lightning as compared to a supercellular or summertime airmass thunderstorm environment.

  19. The development of a scalable parallel 3-D CFD algorithm for turbomachinery. M.S. Thesis Final Report

    NASA Technical Reports Server (NTRS)

    Luke, Edward Allen

    1993-01-01

    Two algorithms capable of computing a transonic 3-D inviscid flow field about rotating machines are considered for parallel implementation. During the study of these algorithms, a significant new method of measuring the performance of parallel algorithms is developed. The theory that supports this new method creates an empirical definition of scalable parallel algorithms that is used to produce quantifiable evidence that a scalable parallel application was developed. The implementation of the parallel application and an automated domain decomposition tool are also discussed.

  20. Bobcat 2013: a hyperspectral data collection supporting the development and evaluation of spatial-spectral algorithms

    NASA Astrophysics Data System (ADS)

    Kaufman, Jason; Celenk, Mehmet; White, A. K.; Stocker, Alan D.

    2014-06-01

    The amount of hyperspectral imagery (HSI) data currently available is relatively small compared to other imaging modalities, and what is suitable for developing, testing, and evaluating spatial-spectral algorithms is virtually nonexistent. In this work, a significant amount of coincident airborne hyperspectral and high spatial resolution panchromatic imagery that supports the advancement of spatial-spectral feature extraction algorithms was collected to address this need. The imagery was collected in April 2013 for Ohio University by the Civil Air Patrol, with their Airborne Real-time Cueing Hyperspectral Enhanced Reconnaissance (ARCHER) sensor. The target materials, shapes, and movements throughout the collection area were chosen such that evaluation of change detection algorithms, atmospheric compensation techniques, image fusion methods, and material detection and identification algorithms is possible. This paper describes the collection plan, data acquisition, and initial analysis of the collected imagery.

  1. Development of a two wheeled self balancing robot with speech recognition and navigation algorithm

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Muhaimin; Ashik-E-Rasul, Haq, Nowab. Md. Aminul; Hassan, Mehedi; Hasib, Irfan Mohammad Al; Hassan, K. M. Rafidh

    2016-07-01

    This paper is aimed to discuss modeling, construction and development of navigation algorithm of a two wheeled self balancing mobile robot in an enclosure. In this paper, we have discussed the design of two of the main controller algorithms, namely PID algorithms, on the robot model. Simulation is performed in the SIMULINK environment. The controller is developed primarily for self-balancing of the robot and also it's positioning. As for the navigation in an enclosure, template matching algorithm is proposed for precise measurement of the robot position. The navigation system needs to be calibrated before navigation process starts. Almost all of the earlier template matching algorithms that can be found in the open literature can only trace the robot. But the proposed algorithm here can also locate the position of other objects in an enclosure, like furniture, tables etc. This will enable the robot to know the exact location of every stationary object in the enclosure. Moreover, some additional features, such as Speech Recognition and Object Detection, are added. For Object Detection, the single board Computer Raspberry Pi is used. The system is programmed to analyze images captured via the camera, which are then processed through background subtraction, followed by active noise reduction.

  2. Development of a fire detection algorithm for the COMS (Communication Ocean and Meteorological Satellite)

    NASA Astrophysics Data System (ADS)

    Kim, Goo; Kim, Dae Sun; Lee, Yang-Won

    2013-10-01

    The forest fires do much damage to our life in ecological and economic aspects. South Korea is probably more liable to suffer from the forest fire because mountain area occupies more than half of land in South Korea. They have recently launched the COMS(Communication Ocean and Meteorological Satellite) which is a geostationary satellite. In this paper, we developed forest fire detection algorithm using COMS data. Generally, forest fire detection algorithm uses characteristics of 4 and 11 micrometer brightness temperature. Our algorithm additionally uses LST(Land Surface Temperature). We confirmed the result of our fire detection algorithm using statistical data of Korea Forest Service and ASTER(Advanced Spaceborne Thermal Emission and Reflection Radiometer) images. We used the data in South Korea On April 1 and 2, 2011 because there are small and big forest fires at that time. The detection rate was 80% in terms of the frequency of the forest fires and was 99% in terms of the damaged area. Considering the number of COMS's channels and its low resolution, this result is a remarkable outcome. To provide users with the result of our algorithm, we developed a smartphone application for users JSP(Java Server Page). This application can work regardless of the smartphone's operating system. This study can be unsuitable for other areas and days because we used just two days data. To improve the accuracy of our algorithm, we need analysis using long-term data as future work.

  3. Development of an Algorithm to Classify Colonoscopy Indication from Coded Health Care Data

    PubMed Central

    Adams, Kenneth F.; Johnson, Eric A.; Chubak, Jessica; Kamineni, Aruna; Doubeni, Chyke A.; Buist, Diana S.M.; Williams, Andrew E.; Weinmann, Sheila; Doria-Rose, V. Paul; Rutter, Carolyn M.

    2015-01-01

    Introduction: Electronic health data are potentially valuable resources for evaluating colonoscopy screening utilization and effectiveness. The ability to distinguish screening colonoscopies from exams performed for other purposes is critical for research that examines factors related to screening uptake and adherence, and the impact of screening on patient outcomes, but distinguishing between these indications in secondary health data proves challenging. The objective of this study is to develop a new and more accurate algorithm for identification of screening colonoscopies using electronic health data. Methods: Data from a case-control study of colorectal cancer with adjudicated colonoscopy indication was used to develop logistic regression-based algorithms. The proposed algorithms predict the probability that a colonoscopy was indicated for screening, with variables selected for inclusion in the models using the Least Absolute Shrinkage and Selection Operator (LASSO). Results: The algorithms had excellent classification accuracy in internal validation. The primary, restricted model had AUC= 0.94, sensitivity=0.91, and specificity=0.82. The secondary, extended model had AUC=0.96, sensitivity=0.88, and specificity=0.90. Discussion: The LASSO approach enabled estimation of parsimonious algorithms that identified screening colonoscopies with high accuracy in our study population. External validation is needed to replicate these results and to explore the performance of these algorithms in other settings. PMID:26290883

  4. A comparison of three self-tuning control algorithms developed for the Bristol-Babcock controller

    SciTech Connect

    Tapp, P.A.

    1992-04-01

    A brief overview of adaptive control methods relating to the design of self-tuning proportional-integral-derivative (PID) controllers is given. The methods discussed include gain scheduling, self-tuning, auto-tuning, and model-reference adaptive control systems. Several process identification and parameter adjustment methods are discussed. Characteristics of the two most common types of self-tuning controllers implemented by industry (i.e., pattern recognition and process identification) are summarized. The substance of the work is a comparison of three self-tuning proportional-plus-integral (STPI) control algorithms developed to work in conjunction with the Bristol-Babcock PID control module. The STPI control algorithms are based on closed-loop cycling theory, pattern recognition theory, and model-based theory. A brief theory of operation of these three STPI control algorithms is given. Details of the process simulations developed to test the STPI algorithms are given, including an integrating process, a first-order system, a second-order system, a system with initial inverse response, and a system with variable time constant and delay. The STPI algorithms' performance with regard to both setpoint changes and load disturbances is evaluated, and their robustness is compared. The dynamic effects of process deadtime and noise are also considered. Finally, the limitations of each of the STPI algorithms is discussed, some conclusions are drawn from the performance comparisons, and a few recommendations are made. 6 refs.

  5. A comparison of three self-tuning control algorithms developed for the Bristol-Babcock controller

    SciTech Connect

    Tapp, P.A.

    1992-04-01

    A brief overview of adaptive control methods relating to the design of self-tuning proportional-integral-derivative (PID) controllers is given. The methods discussed include gain scheduling, self-tuning, auto-tuning, and model-reference adaptive control systems. Several process identification and parameter adjustment methods are discussed. Characteristics of the two most common types of self-tuning controllers implemented by industry (i.e., pattern recognition and process identification) are summarized. The substance of the work is a comparison of three self-tuning proportional-plus-integral (STPI) control algorithms developed to work in conjunction with the Bristol-Babcock PID control module. The STPI control algorithms are based on closed-loop cycling theory, pattern recognition theory, and model-based theory. A brief theory of operation of these three STPI control algorithms is given. Details of the process simulations developed to test the STPI algorithms are given, including an integrating process, a first-order system, a second-order system, a system with initial inverse response, and a system with variable time constant and delay. The STPI algorithms` performance with regard to both setpoint changes and load disturbances is evaluated, and their robustness is compared. The dynamic effects of process deadtime and noise are also considered. Finally, the limitations of each of the STPI algorithms is discussed, some conclusions are drawn from the performance comparisons, and a few recommendations are made. 6 refs.

  6. TIGER: Development of Thermal Gradient Compensation Algorithms and Techniques

    NASA Technical Reports Server (NTRS)

    Hereford, James; Parker, Peter A.; Rhew, Ray D.

    2004-01-01

    In a wind tunnel facility, the direct measurement of forces and moments induced on the model are performed by a force measurement balance. The measurement balance is a precision-machined device that has strain gages at strategic locations to measure the strain (i.e., deformations) due to applied forces and moments. The strain gages convert the strain (and hence the applied force) to an electrical voltage that is measured by external instruments. To address the problem of thermal gradients on the force measurement balance NASA-LaRC has initiated a research program called TIGER - Thermally-Induced Gradients Effects Research. The ultimate goals of the TIGER program are to: (a) understand the physics of the thermally-induced strain and its subsequent impact on load measurements and (b) develop a robust thermal gradient compensation technique. This paper will discuss the impact of thermal gradients on force measurement balances, specific aspects of the TIGER program (the design of a special-purpose balance, data acquisition and data analysis challenges), and give an overall summary.

  7. Development of a rule-based algorithm for rice cultivation mapping using Landsat 8 time series

    NASA Astrophysics Data System (ADS)

    Karydas, Christos G.; Toukiloglou, Pericles; Minakou, Chara; Gitas, Ioannis Z.

    2015-06-01

    In the framework of ERMES project (FP7 66983), an algorithm for mapping rice cultivation extents using mediumhigh resolution satellite data was developed. ERMES (An Earth obseRvation Model based RicE information Service) aims to develop a prototype of downstream service for rice yield modelling based on a combination of Earth Observation and in situ data. The algorithm was designed as a set of rules applied on a time series of Landsat 8 images, acquired throughout the rice cultivation season of 2014 from the plain of Thessaloniki, Greece. The rules rely on the use of spectral indices, such as the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Water Index (NDWI), and the Normalized Seasonal Wetness Index (NSWI), extracted from the Landsat 8 dataset. The algorithm is subdivided into two phases: a) a hard classification phase, resulting in a binary map (rice/no-rice), where pixels are judged according to their performance in all the images of the time series, while index thresholds were defined after a trial and error approach; b) a soft classification phase, resulting in a fuzzy map, by assigning scores to the pixels which passed (as `rice') the first phase. Finally, a user-defined threshold of the fuzzy score will discriminate rice from no-rice pixels in the output map. The algorithm was tested in a subset of Thessaloniki plain against a set of selected field data. The results indicated an overall accuracy of the algorithm higher than 97%. The algorithm was also applied in a study are in Spain (Valencia) and a preliminary test indicated a similar performance, i.e. about 98%. Currently, the algorithm is being modified, so as to map rice extents early in the cultivation season (by the end of June), with a view to contribute more substantially to the rice yield prediction service of ERMES. Both algorithm modes (late and early) are planned to be tested in extra Mediterranean study areas, in Greece, Italy, and Spain.

  8. Automated Development of Accurate Algorithms and Efficient Codes for Computational Aeroacoustics

    NASA Technical Reports Server (NTRS)

    Goodrich, John W.; Dyson, Rodger W.

    1999-01-01

    The simulation of sound generation and propagation in three space dimensions with realistic aircraft components is a very large time dependent computation with fine details. Simulations in open domains with embedded objects require accurate and robust algorithms for propagation, for artificial inflow and outflow boundaries, and for the definition of geometrically complex objects. The development, implementation, and validation of methods for solving these demanding problems is being done to support the NASA pillar goals for reducing aircraft noise levels. Our goal is to provide algorithms which are sufficiently accurate and efficient to produce usable results rapidly enough to allow design engineers to study the effects on sound levels of design changes in propulsion systems, and in the integration of propulsion systems with airframes. There is a lack of design tools for these purposes at this time. Our technical approach to this problem combines the development of new, algorithms with the use of Mathematica and Unix utilities to automate the algorithm development, code implementation, and validation. We use explicit methods to ensure effective implementation by domain decomposition for SPMD parallel computing. There are several orders of magnitude difference in the computational efficiencies of the algorithms which we have considered. We currently have new artificial inflow and outflow boundary conditions that are stable, accurate, and unobtrusive, with implementations that match the accuracy and efficiency of the propagation methods. The artificial numerical boundary treatments have been proven to have solutions which converge to the full open domain problems, so that the error from the boundary treatments can be driven as low as is required. The purpose of this paper is to briefly present a method for developing highly accurate algorithms for computational aeroacoustics, the use of computer automation in this process, and a brief survey of the algorithms that

  9. Genetic algorithms

    NASA Technical Reports Server (NTRS)

    Wang, Lui; Bayer, Steven E.

    1991-01-01

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

  10. Correlation signatures of wet soils and snows. [algorithm development and computer programming

    NASA Technical Reports Server (NTRS)

    Phillips, M. R.

    1972-01-01

    Interpretation, analysis, and development of algorithms have provided the necessary computational programming tools for soil data processing, data handling and analysis. Algorithms that have been developed thus far, are adequate and have been proven successful for several preliminary and fundamental applications such as software interfacing capabilities, probability distributions, grey level print plotting, contour plotting, isometric data displays, joint probability distributions, boundary mapping, channel registration and ground scene classification. A description of an Earth Resources Flight Data Processor, (ERFDP), which handles and processes earth resources data under a users control is provided.

  11. Developing Subdomain Allocation Algorithms Based on Spatial and Communicational Constraints to Accelerate Dust Storm Simulation

    PubMed Central

    Gui, Zhipeng; Yu, Manzhu; Yang, Chaowei; Jiang, Yunfeng; Chen, Songqing; Xia, Jizhe; Huang, Qunying; Liu, Kai; Li, Zhenlong; Hassan, Mohammed Anowarul; Jin, Baoxuan

    2016-01-01

    Dust storm has serious disastrous impacts on environment, human health, and assets. The developments and applications of dust storm models have contributed significantly to better understand and predict the distribution, intensity and structure of dust storms. However, dust storm simulation is a data and computing intensive process. To improve the computing performance, high performance computing has been widely adopted by dividing the entire study area into multiple subdomains and allocating each subdomain on different computing nodes in a parallel fashion. Inappropriate allocation may introduce imbalanced task loads and unnecessary communications among computing nodes. Therefore, allocation is a key factor that may impact the efficiency of parallel process. An allocation algorithm is expected to consider the computing cost and communication cost for each computing node to minimize total execution time and reduce overall communication cost for the entire simulation. This research introduces three algorithms to optimize the allocation by considering the spatial and communicational constraints: 1) an Integer Linear Programming (ILP) based algorithm from combinational optimization perspective; 2) a K-Means and Kernighan-Lin combined heuristic algorithm (K&K) integrating geometric and coordinate-free methods by merging local and global partitioning; 3) an automatic seeded region growing based geometric and local partitioning algorithm (ASRG). The performance and effectiveness of the three algorithms are compared based on different factors. Further, we adopt the K&K algorithm as the demonstrated algorithm for the experiment of dust model simulation with the non-hydrostatic mesoscale model (NMM-dust) and compared the performance with the MPI default sequential allocation. The results demonstrate that K&K method significantly improves the simulation performance with better subdomain allocation. This method can also be adopted for other relevant atmospheric and numerical

  12. Developing Subdomain Allocation Algorithms Based on Spatial and Communicational Constraints to Accelerate Dust Storm Simulation.

    PubMed

    Gui, Zhipeng; Yu, Manzhu; Yang, Chaowei; Jiang, Yunfeng; Chen, Songqing; Xia, Jizhe; Huang, Qunying; Liu, Kai; Li, Zhenlong; Hassan, Mohammed Anowarul; Jin, Baoxuan

    2016-01-01

    Dust storm has serious disastrous impacts on environment, human health, and assets. The developments and applications of dust storm models have contributed significantly to better understand and predict the distribution, intensity and structure of dust storms. However, dust storm simulation is a data and computing intensive process. To improve the computing performance, high performance computing has been widely adopted by dividing the entire study area into multiple subdomains and allocating each subdomain on different computing nodes in a parallel fashion. Inappropriate allocation may introduce imbalanced task loads and unnecessary communications among computing nodes. Therefore, allocation is a key factor that may impact the efficiency of parallel process. An allocation algorithm is expected to consider the computing cost and communication cost for each computing node to minimize total execution time and reduce overall communication cost for the entire simulation. This research introduces three algorithms to optimize the allocation by considering the spatial and communicational constraints: 1) an Integer Linear Programming (ILP) based algorithm from combinational optimization perspective; 2) a K-Means and Kernighan-Lin combined heuristic algorithm (K&K) integrating geometric and coordinate-free methods by merging local and global partitioning; 3) an automatic seeded region growing based geometric and local partitioning algorithm (ASRG). The performance and effectiveness of the three algorithms are compared based on different factors. Further, we adopt the K&K algorithm as the demonstrated algorithm for the experiment of dust model simulation with the non-hydrostatic mesoscale model (NMM-dust) and compared the performance with the MPI default sequential allocation. The results demonstrate that K&K method significantly improves the simulation performance with better subdomain allocation. This method can also be adopted for other relevant atmospheric and numerical

  13. Developing Subdomain Allocation Algorithms Based on Spatial and Communicational Constraints to Accelerate Dust Storm Simulation.

    PubMed

    Gui, Zhipeng; Yu, Manzhu; Yang, Chaowei; Jiang, Yunfeng; Chen, Songqing; Xia, Jizhe; Huang, Qunying; Liu, Kai; Li, Zhenlong; Hassan, Mohammed Anowarul; Jin, Baoxuan

    2016-01-01

    Dust storm has serious disastrous impacts on environment, human health, and assets. The developments and applications of dust storm models have contributed significantly to better understand and predict the distribution, intensity and structure of dust storms. However, dust storm simulation is a data and computing intensive process. To improve the computing performance, high performance computing has been widely adopted by dividing the entire study area into multiple subdomains and allocating each subdomain on different computing nodes in a parallel fashion. Inappropriate allocation may introduce imbalanced task loads and unnecessary communications among computing nodes. Therefore, allocation is a key factor that may impact the efficiency of parallel process. An allocation algorithm is expected to consider the computing cost and communication cost for each computing node to minimize total execution time and reduce overall communication cost for the entire simulation. This research introduces three algorithms to optimize the allocation by considering the spatial and communicational constraints: 1) an Integer Linear Programming (ILP) based algorithm from combinational optimization perspective; 2) a K-Means and Kernighan-Lin combined heuristic algorithm (K&K) integrating geometric and coordinate-free methods by merging local and global partitioning; 3) an automatic seeded region growing based geometric and local partitioning algorithm (ASRG). The performance and effectiveness of the three algorithms are compared based on different factors. Further, we adopt the K&K algorithm as the demonstrated algorithm for the experiment of dust model simulation with the non-hydrostatic mesoscale model (NMM-dust) and compared the performance with the MPI default sequential allocation. The results demonstrate that K&K method significantly improves the simulation performance with better subdomain allocation. This method can also be adopted for other relevant atmospheric and numerical

  14. Utilization of Ancillary Data Sets for SMAP Algorithm Development and Product Generation

    NASA Technical Reports Server (NTRS)

    ONeill, P.; Podest, E.; Njoku, E.

    2011-01-01

    Algorithms being developed for the Soil Moisture Active Passive (SMAP) mission require a variety of both static and ancillary data. The selection of the most appropriate source for each ancillary data parameter is driven by a number of considerations, including accuracy, latency, availability, and consistency across all SMAP products and with SMOS (Soil Moisture Ocean Salinity). It is anticipated that initial selection of all ancillary datasets, which are needed for ongoing algorithm development activities on the SMAP algorithm testbed at JPL, will be completed within the year. These datasets will be updated as new or improved sources become available, and all selections and changes will be documented for the benefit of the user community. Wise choices in ancillary data will help to enable SMAP to provide new global measurements of soil moisture and freeze/thaw state at the targeted accuracy necessary to tackle hydrologically-relevant societal issues.

  15. Development and validation of evolutionary algorithm software as an optimization tool for biological and environmental applications.

    PubMed

    Sys, K; Boon, N; Verstraete, W

    2004-06-01

    A flexible, extendable tool for the optimization of (micro)biological processes and protocols using evolutionary algorithms was developed. It has been tested using three different theoretical optimization problems: 2 two-dimensional problems, one with three maxima and one with five maxima and a river autopurification optimization problem with boundary conditions. For each problem, different evolutionary parameter settings were used for the optimization. For each combination of evolutionary parameters, 15 generations were run 20 times. It has been shown that in all cases, the evolutionary algorithm gave rise to valuable results. Generally, the algorithms were able to detect the more stable sub-maximum even if there existed less stable maxima. The latter is, from a practical point of view, generally more desired. The most important factors influencing the convergence process were the parameter value randomization rate and distribution. The developed software, described in this work, is available for free.

  16. Applications and development of new algorithms for displacement analysis using InSAR time series

    NASA Astrophysics Data System (ADS)

    Osmanoglu, Batuhan

    -dimensional (3-D) phase unwrapping. Chapter 4 focuses on the unwrapping path. Unwrapping algorithms can be divided into two groups, path-dependent and path-independent algorithms. Path-dependent algorithms use local unwrapping functions applied pixel-by-pixel to the dataset. In contrast, path-independent algorithms use global optimization methods such as least squares, and return a unique solution. However, when aliasing and noise are present, path-independent algorithms can underestimate the signal in some areas due to global fitting criteria. Path-dependent algorithms do not underestimate the signal, but, as the name implies, the unwrapping path can affect the result. Comparison between existing path algorithms and a newly developed algorithm based on Fisher information theory was conducted. Results indicate that Fisher information theory does indeed produce lower misfit results for most tested cases. Chapter 5 presents a new time series analysis method based on 3-D unwrapping of SAR data using extended Kalman filters. Existing methods for time series generation using InSAR data employ special filters to combine two-dimensional (2-D) spatial unwrapping with one-dimensional (1-D) temporal unwrapping results. The new method, however, combines observations in azimuth, range and time for repeat pass interferometry. Due to the pixel-by-pixel characteristic of the filter, the unwrapping path is selected based on a quality map. This unwrapping algorithm is the first application of extended Kalman filters to the 3-D unwrapping problem. Time series analyses of InSAR data are used in a variety of applications with different characteristics. Consequently, it is difficult to develop a single algorithm that can provide optimal results in all cases, given that different algorithms possess a unique set of strengths and weaknesses. Nonetheless, filter-based unwrapping algorithms such as the one presented in this dissertation have the capability of joining multiple observations into a uniform

  17. Authentication of the botanical origin of unifloral honey by infrared spectroscopy coupled with support vector machine algorithm

    NASA Astrophysics Data System (ADS)

    Lenhardt, L.; Zeković, I.; Dramićanin, T.; Tešić, Ž.; Milojković-Opsenica, D.; Dramićanin, M. D.

    2014-09-01

    In recent years, the potential of Fourier-transform infrared spectroscopy coupled with different chemometric tools in food analysis has been established. This technique is rapid, low cost, and reliable and requires little sample preparation. In this work, 130 Serbian unifloral honey samples (linden, acacia, and sunflower types) were analyzed using attenuated total reflectance infrared spectroscopy (ATR-IR). For each spectrum, 64 scans were recorded in wavenumbers between 4000 and 500 cm-1 and at a spectral resolution of 4 cm-1. These spectra were analyzed using principal component analysis (PCA), and calculated principal components were then used for support vector machine (SVM) training. In this way, the pattern-recognition tool is obtained for building a classification model for determining the botanical origin of honey. The PCA was used to analyze results and to see if the separation between groups of different types of honeys exists. Using the SVM, the classification model was built and classification errors were acquired. It has been observed that this technique is adequate for determining the botanical origin of honey with a success rate of 98.6%. Based on these results, it can be concluded that this technique offers many possibilities for future rapid qualitative analysis of honey.

  18. Developments in the Aerosol Layer Height Retrieval Algorithm for the Copernicus Sentinel-4/UVN Instrument

    NASA Astrophysics Data System (ADS)

    Nanda, Swadhin; Sanders, Abram; Veefkind, Pepijn

    2016-04-01

    The Sentinel-4 mission is a part of the European Commission's Copernicus programme, the goal of which is to provide geo-information to manage environmental assets, and to observe, understand and mitigate the effects of the changing climate. The Sentinel-4/UVN instrument design is motivated by the need to monitor trace gas concentrations and aerosols in the atmosphere from a geostationary orbit. The on-board instrument is a high resolution UV-VIS-NIR (UVN) spectrometer system that provides hourly radiance measurements over Europe and northern Africa with a spatial sampling of 8 km. The main application area of Sentinel-4/UVN is air quality. One of the data products that is being developed for Sentinel-4/UVN is the Aerosol Layer Height (ALH). The goal is to determine the height of aerosol plumes with a resolution of better than 0.5 - 1 km. The ALH product thus targets aerosol layers in the free troposphere, such as desert dust, volcanic ash and biomass during plumes. KNMI is assigned with the development of the Aerosol Layer Height (ALH) algorithm. Its heritage is the ALH algorithm developed by Sanders and De Haan (ATBD, 2016) for the TROPOMI instrument on board the Sentinel-5 Precursor mission that is to be launched in June or July 2016 (tentative date). The retrieval algorithm designed so far for the aerosol height product is based on the absorption characteristics of the oxygen-A band (759-770 nm). The algorithm has heritage to the ALH algorithm developed for TROPOMI on the Sentinel 5 precursor satellite. New aspects for Sentinel-4/UVN include the higher resolution (0.116 nm compared to 0.4 for TROPOMI) and hourly observation from the geostationary orbit. The algorithm uses optimal estimation to obtain a spectral fit of the reflectance across absorption band, while assuming a single uniform layer with fixed width to represent the aerosol vertical distribution. The state vector includes amongst other elements the height of this layer and its aerosol optical

  19. Development and Evaluation of Model Algorithms to Account for Chemical Transformation in the Nearroad Environment

    EPA Science Inventory

    We describe the development and evaluation of two new model algorithms for NOx chemistry in the R-LINE near-road dispersion model for traffic sources. With increased urbanization, there is increased mobility leading to higher amount of traffic related activity on a global scale. ...

  20. Development of sub-daily erosion and sediment transport algorithms in SWAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New Soil and Water Assessment Tool (SWAT) algorithms for simulation of stormwater best management practices (BMPs) such as detention basins, wet ponds, sedimentation filtration ponds, and retention irrigation systems are under development for modeling small/urban watersheds. Modeling stormwater BMPs...

  1. Scheduling language and algorithm development study. Appendix: Study approach and activity summary

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The approach and organization of the study to develop a high level computer programming language and a program library are presented. The algorithm and problem modeling analyses are summarized. The approach used to identify and specify the capabilities required in the basic language is described. Results of the analyses used to define specifications for the scheduling module library are presented.

  2. Ocean Observations with EOS/MODIS: Algorithm Development and Post Launch Studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1997-01-01

    The following accomplishments were made during the present reporting period: (1) We expanded our new method, for identifying the presence of absorbing aerosols and simultaneously performing atmospheric correction, to the point where it could be added as a subroutine to the MODIS water-leaving radiance algorithm; (2) We successfully acquired micro pulse lidar (MPL) data at sea during a cruise in February; (3) We developed a water-leaving radiance algorithm module for an approximate correction of the MODIS instrument polarization sensitivity; and (4) We participated in one cruise to the Gulf of Maine, a well known region for mesoscale coccolithophore blooms. We measured coccolithophore abundance, production and optical properties.

  3. Ocean observations with EOS/MODIS: Algorithm Development and Post Launch Studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1998-01-01

    Significant accomplishments made during the present reporting period: (1) We expanded our "spectral-matching" algorithm (SMA), for identifying the presence of absorbing aerosols and simultaneously performing atmospheric correction and derivation of the ocean's bio-optical parameters, to the point where it could be added as a subroutine to the MODIS water-leaving radiance algorithm; (2) A modification to the SMA that does not require detailed aerosol models has been developed. This is important as the requirement for realistic aerosol models has been a weakness of the SMA; and (3) We successfully acquired micro pulse lidar data in a Saharan dust outbreak during ACE-2 in the Canary Islands.

  4. Development of fetal brain renin–angiotensin system and hypertension programmed in fetal origins

    PubMed Central

    Mao, Caiping; Shi, Lijun; Xu, Feichao; Zhang, Lubo; Xu, Zhice

    2010-01-01

    Since the concept of fetal origins of adult diseases was introduced in 1980s, the development of the renin–angiotensin system (RAS) in normal and abnormal patterns has attracted attention. Recent studies have shown the importance of the fetal RAS in both prenatal and postnatal development. This review focuses on the functional development of the fetal brain RAS, and ontogeny of local brain RAS components in utero. The central RAS plays an important role in the control of fetal cardiovascular responses, body fluid balance, and neuroendocrine regulation. Recent progress has been made in demonstrating that altered fetal RAS development as a consequence of environmental insults may impact on “programming” of hypertension later in life. Given that the central RAS is of equal importance to the peripheral RAS in cardiovascular regulation, studies on the fetal brain RAS development in normal and abnormal patterns could shed light on “programming” mechanisms of adult cardiovascular diseases in fetal origins. PMID:19428956

  5. Development and benefit analysis of a sector design algorithm for terminal dynamic airspace configuration

    NASA Astrophysics Data System (ADS)

    Sciandra, Vincent

    The National Airspace System (NAS) is the vast network of systems enabling safe and efficient air travel in the United States. It consists of a set of static sectors, each controlled by one or more air traffic controllers. Air traffic control is tasked with ensuring that all flights can depart and arrive on time and in a safe and efficient matter. However, skyrocketing demand will only increase the stress on an already inefficient system, causing massive delays. The current, static configuration of the NAS cannot possibly handle the future demand on the system safely and efficiently, especially since it is projected to triple by 2025. To overcome these issues, the Next Generation of Air Transportation System (NextGen) is being enacted to increase the flexibility of the NAS. A major objective of NextGen is to implement Adaptable Dynamic Airspace Configuration (ADAC) which will dynamically allocate the sectors to best fit the traffic in the area. Dynamically allocating sectors will allow resources such as controllers to be better distributed to meet traffic demands. Currently, most DAC research has involved the en route airspace. This leaves the terminal airspace, which accounts for a large amount of the overall NAS complexity, in need of work. Using a combination of methods used in en route sectorization, this thesis has developed an algorithm for the dynamic allocation of sectors in the terminal airspace. This algorithm will be evaluated using metrics common in the evaluation of dynamic density, which is adapted for the unique challenges of the terminal airspace, and used to measure workload on air traffic controllers. These metrics give a better view of the controller workload than the number of aircraft alone. By comparing the test results with sectors currently used in the NAS using real traffic data, the algorithm xv generated sectors can be quantitatively evaluated for improvement of the current sectorizations. This will be accomplished by testing the

  6. Development of a 2-D algorithm to simulate convection and phase transition efficiently

    NASA Astrophysics Data System (ADS)

    Evans, Katherine J.; Knoll, D. A.; Pernice, Michael

    2006-11-01

    We develop a Jacobian-Free Newton-Krylov (JFNK) method for the solution of a two-dimensional convection phase change model using the incompressible Navier-Stokes equation set and enthalpy as the energy conservation variable. The SIMPLE algorithm acts as a physics-based preconditioner to JFNK. This combined algorithm is compared to solutions using SIMPLE as the main solver. Algorithm performance is assessed for two benchmark problems of phase change convection of a pure material, one melting and one freezing. The JFNK-SIMPLE method is shown to be more efficient per time step and more robust at larger time steps. Overall CPU savings of more than an order of magnitude are realized.

  7. Development of the Landsat Data Continuity Mission Cloud Cover Assessment Algorithms

    USGS Publications Warehouse

    Scaramuzza, Pat; Bouchard, M.A.; Dwyer, J.L.

    2012-01-01

    The upcoming launch of the Operational Land Imager (OLI) will start the next era of the Landsat program. However, the Automated Cloud-Cover Assessment (CCA) (ACCA) algorithm used on Landsat 7 requires a thermal band and is thus not suited for OLI. There will be a thermal instrument on the Landsat Data Continuity Mission (LDCM)-the Thermal Infrared Sensor-which may not be available during all OLI collections. This illustrates a need for CCA for LDCM in the absence of thermal data. To research possibilities for full-resolution OLI cloud assessment, a global data set of 207 Landsat 7 scenes with manually generated cloud masks was created. It was used to evaluate the ACCA algorithm, showing that the algorithm correctly classified 79.9% of a standard test subset of 3.95 109 pixels. The data set was also used to develop and validate two successor algorithms for use with OLI data-one derived from an off-the-shelf machine learning package and one based on ACCA but enhanced by a simple neural network. These comprehensive CCA algorithms were shown to correctly classify pixels as cloudy or clear 88.5% and 89.7% of the time, respectively.

  8. Millimeter-Wave Imaging Radiometer (MIR) Data Processing and Development of Water Vapor Retrieval Algorithms

    NASA Technical Reports Server (NTRS)

    Chang, L. Aron

    1998-01-01

    This document describes the final report of the Millimeter-wave Imaging Radiometer (MIR) Data Processing and Development of Water Vapor Retrieval Algorithms. Volumes of radiometric data have been collected using airborne MIR measurements during a series of field experiments since May 1992. Calibrated brightness temperature data in MIR channels are now available for studies of various hydrological parameters of the atmosphere and Earth's surface. Water vapor retrieval algorithms using multichannel MIR data input are developed for the profiling of atmospheric humidity. The retrieval algorithms are also extended to do three-dimensional mapping of moisture field using continuous observation provided by airborne sensor MIR or spaceborne sensor SSM/T-2. Validation studies for water vapor retrieval are carried out through the intercomparison of collocated and concurrent measurements using different instruments including lidars and radiosondes. The developed MIR water vapor retrieval algorithm is capable of humidity profiling under meteorological conditions ranging from clear column to moderately cloudy sky. Simulative water vapor retrieval studies using extended microwave channels near 183 and 557 GHz strong absorption lines indicate feasibility of humidity profiling to layers in the upper troposphere and improve the overall vertical resolution through the atmosphere.

  9. SPHERES as Formation Flight Algorithm Development and Validation Testbed: Current Progress and Beyond

    NASA Technical Reports Server (NTRS)

    Kong, Edmund M.; Saenz-Otero, Alvar; Nolet, Simon; Berkovitz, Dustin S.; Miller, David W.; Sell, Steve W.

    2004-01-01

    The MIT-SSL SPHERES testbed provides a facility for the development of algorithms necessary for the success of Distributed Satellite Systems (DSS). The initial development contemplated formation flight and docking control algorithms; SPHERES now supports the study of metrology, control, autonomy, artificial intelligence, and communications algorithms and their effects on DSS projects. To support this wide range of topics, the SPHERES design contemplated the need to support multiple researchers, as echoed from both the hardware and software designs. The SPHERES operational plan further facilitates the development of algorithms by multiple researchers, while the operational locations incrementally increase the ability of the tests to operate in a representative environment. In this paper, an overview of the SPHERES testbed is first presented. The SPHERES testbed serves as a model of the design philosophies that allow for the various researches being carried out on such a facility. The implementation of these philosophies are further highlighted in the three different programs that are currently scheduled for testing onboard the International Space Station (ISS) and three that are proposed for a re-flight mission: Mass Property Identification, Autonomous Rendezvous and Docking, TPF Multiple Spacecraft Formation Flight in the first flight and Precision Optical Pointing, Tethered Formation Flight and Mars Orbit Sample Retrieval for the re-flight mission.

  10. An Improved Greedy Search Algorithm for the Development of a Phonetically Rich Speech Corpus

    NASA Astrophysics Data System (ADS)

    Zhang, Jin-Song; Nakamura, Satoshi

    An efficient way to develop large scale speech corpora is to collect phonetically rich ones that have high coverage of phonetic contextual units. The sentence set, usually called as the minimum set, should have small text size in order to reduce the collection cost. It can be selected by a greedy search algorithm from a large mother text corpus. With the inclusion of more and more phonetic contextual effects, the number of different phonetic contextual units increased dramatically, making the search not a trivial issue. In order to improve the search efficiency, we previously proposed a so-called least-to-most-ordered greedy search based on the conventional algorithms. This paper evaluated these algorithms in order to show their different characteristics. The experimental results showed that the least-to-most-ordered methods successfully achieved smaller objective sets at significantly less computation time, when compared with the conventional ones. This algorithm has already been applied to the development a number of speech corpora, including a large scale phonetically rich Chinese speech corpus ATRPTH which played an important role in developing our multi-language translation system.

  11. Units and Systems of Weights and Measures, Their Origin, Development, and Present Status.

    ERIC Educational Resources Information Center

    Barbrow, L. E.

    This newsletter, adapted in 1976 from one originally published in 1960, reviews the subject of weights and measures from several standpoints. It deals first with the historical development of standard systems of measurement, discussing both the metric and English systems. The second section defines a variety of units and describes standardization…

  12. The Influences of the Family of Origin on Career Development: A Review and Analysis. Major Contribution

    ERIC Educational Resources Information Center

    Whiston, Susan C.; Keller, Briana K.

    2004-01-01

    Based on a developmental contextual perspective advocated by Vondracek, Lerner, and Schulenberg, this article provides a comprehensive review of the research published since 1980 related to family of origin influences on career development and occupational choice. Because individuals are most likely to seek assistance with career decisions from…

  13. Integrated Graphics Operations and Analysis Lab Development of Advanced Computer Graphics Algorithms

    NASA Technical Reports Server (NTRS)

    Wheaton, Ira M.

    2011-01-01

    The focus of this project is to aid the IGOAL in researching and implementing algorithms for advanced computer graphics. First, this project focused on porting the current International Space Station (ISS) Xbox experience to the web. Previously, the ISS interior fly-around education and outreach experience only ran on an Xbox 360. One of the desires was to take this experience and make it into something that can be put on NASA s educational site for anyone to be able to access. The current code works in the Unity game engine which does have cross platform capability but is not 100% compatible. The tasks for an intern to complete this portion consisted of gaining familiarity with Unity and the current ISS Xbox code, porting the Xbox code to the web as is, and modifying the code to work well as a web application. In addition, a procedurally generated cloud algorithm will be developed. Currently, the clouds used in AGEA animations and the Xbox experiences are a texture map. The desire is to create a procedurally generated cloud algorithm to provide dynamically generated clouds for both AGEA animations and the Xbox experiences. This task consists of gaining familiarity with AGEA and the plug-in interface, developing the algorithm, creating an AGEA plug-in to implement the algorithm inside AGEA, and creating a Unity script to implement the algorithm for the Xbox. This portion of the project was unable to be completed in the time frame of the internship; however, the IGOAL will continue to work on it in the future.

  14. Femtosecond free-electron laser x-ray diffraction data sets for algorithm development.

    PubMed

    Kassemeyer, Stephan; Steinbrener, Jan; Lomb, Lukas; Hartmann, Elisabeth; Aquila, Andrew; Barty, Anton; Martin, Andrew V; Hampton, Christina Y; Bajt, Saša; Barthelmess, Miriam; Barends, Thomas R M; Bostedt, Christoph; Bott, Mario; Bozek, John D; Coppola, Nicola; Cryle, Max; DePonte, Daniel P; Doak, R Bruce; Epp, Sascha W; Erk, Benjamin; Fleckenstein, Holger; Foucar, Lutz; Graafsma, Heinz; Gumprecht, Lars; Hartmann, Andreas; Hartmann, Robert; Hauser, Günter; Hirsemann, Helmut; Hömke, André; Holl, Peter; Jönsson, Olof; Kimmel, Nils; Krasniqi, Faton; Liang, Mengning; Maia, Filipe R N C; Marchesini, Stefano; Nass, Karol; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Schmidt, Carlo; Schulz, Joachim; Shoeman, Robert L; Sierra, Raymond G; Soltau, Heike; Spence, John C H; Starodub, Dmitri; Stellato, Francesco; Stern, Stephan; Stier, Gunter; Svenda, Martin; Weidenspointner, Georg; Weierstall, Uwe; White, Thomas A; Wunderer, Cornelia; Frank, Matthias; Chapman, Henry N; Ullrich, Joachim; Strüder, Lothar; Bogan, Michael J; Schlichting, Ilme

    2012-02-13

    We describe femtosecond X-ray diffraction data sets of viruses and nanoparticles collected at the Linac Coherent Light Source. The data establish the first large benchmark data sets for coherent diffraction methods freely available to the public, to bolster the development of algorithms that are essential for developing this novel approach as a useful imaging technique. Applications are 2D reconstructions, orientation classification and finally 3D imaging by assembling 2D patterns into a 3D diffraction volume.

  15. Femtosecond free-electron laser x-ray diffraction data sets for algorithm development.

    PubMed

    Kassemeyer, Stephan; Steinbrener, Jan; Lomb, Lukas; Hartmann, Elisabeth; Aquila, Andrew; Barty, Anton; Martin, Andrew V; Hampton, Christina Y; Bajt, Saša; Barthelmess, Miriam; Barends, Thomas R M; Bostedt, Christoph; Bott, Mario; Bozek, John D; Coppola, Nicola; Cryle, Max; DePonte, Daniel P; Doak, R Bruce; Epp, Sascha W; Erk, Benjamin; Fleckenstein, Holger; Foucar, Lutz; Graafsma, Heinz; Gumprecht, Lars; Hartmann, Andreas; Hartmann, Robert; Hauser, Günter; Hirsemann, Helmut; Hömke, André; Holl, Peter; Jönsson, Olof; Kimmel, Nils; Krasniqi, Faton; Liang, Mengning; Maia, Filipe R N C; Marchesini, Stefano; Nass, Karol; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Schmidt, Carlo; Schulz, Joachim; Shoeman, Robert L; Sierra, Raymond G; Soltau, Heike; Spence, John C H; Starodub, Dmitri; Stellato, Francesco; Stern, Stephan; Stier, Gunter; Svenda, Martin; Weidenspointner, Georg; Weierstall, Uwe; White, Thomas A; Wunderer, Cornelia; Frank, Matthias; Chapman, Henry N; Ullrich, Joachim; Strüder, Lothar; Bogan, Michael J; Schlichting, Ilme

    2012-02-13

    We describe femtosecond X-ray diffraction data sets of viruses and nanoparticles collected at the Linac Coherent Light Source. The data establish the first large benchmark data sets for coherent diffraction methods freely available to the public, to bolster the development of algorithms that are essential for developing this novel approach as a useful imaging technique. Applications are 2D reconstructions, orientation classification and finally 3D imaging by assembling 2D patterns into a 3D diffraction volume. PMID:22418172

  16. Strain characterization of Echinococcus granulosus protoscoleces of cattle origin using the in vitro vesicular development.

    PubMed

    Elissondo, M C; Dopchiz, M C; Zanini, F; Pérez, H; Brasesco, M; Denegri, G

    2005-06-01

    The aim of this work was to characterize the strain of protoscoleces of E. granulosus of cattle origin using the in vitro vesicular development. The in vitro development of these samples was compared to samples of sheep origin determined previously by genetic analyses as common sheep strain (G1). There were similarities between sheep and cattle samples not only in the time of microcysts formation, but also in the development process. Vesiculated protoscoleces and protoscoleces with posterior bladders appeared during the first week of incubation. After 14 days of culture, a laminated layer appeared like a fine membrane in one of the extremes of the protoscoleces. In the sheep samples, microcysts were observed between 19 and 20 days. In the cattle samples, microcysts appeared between 20 and 23 days. The coincidence between the development times and physiological characteristics found in the present study may indicate that the parasites from cattle and sheep were of the same strain.

  17. Development of sensor-based nitrogen recommendation algorithms for cereal crops

    NASA Astrophysics Data System (ADS)

    Asebedo, Antonio Ray

    Nitrogen (N) management is one of the most recognizable components of farming both within and outside the world of agriculture. Interest over the past decade has greatly increased in improving N management systems in corn (Zea mays) and winter wheat (Triticum aestivum ) to have high NUE, high yield, and be environmentally sustainable. Nine winter wheat experiments were conducted across seven locations from 2011 through 2013. The objectives of this study were to evaluate the impacts of fall-winter, Feekes 4, Feekes 7, and Feekes 9 N applications on winter wheat grain yield, grain protein, and total grain N uptake. Nitrogen treatments were applied as single or split applications in the fall-winter, and top-dressed in the spring at Feekes 4, Feekes 7, and Feekes 9 with applied N rates ranging from 0 to 134 kg ha-1. Results indicate that Feekes 7 and 9 N applications provide more optimal combinations of grain yield, grain protein levels, and fertilizer N recovered in the grain when compared to comparable rates of N applied in the fall-winter or at Feekes 4. Winter wheat N management studies from 2006 through 2013 were utilized to develop sensor-based N recommendation algorithms for winter wheat in Kansas. Algorithm RosieKat v.2.6 was designed for multiple N application strategies and utilized N reference strips for establishing N response potential. Algorithm NRS v1.5 addressed single top-dress N applications and does not require a N reference strip. In 2013, field validations of both algorithms were conducted at eight locations across Kansas. Results show algorithm RK v2.6 consistently provided highly efficient N recommendations for improving NUE, while achieving high grain yield and grain protein. Without the use of the N reference strip, NRS v1.5 performed statistically equal to the KSU soil test N recommendation in regards to grain yield but with lower applied N rates. Six corn N fertigation experiments were conducted at KSU irrigated experiment fields from 2012

  18. Review and Analysis of Algorithmic Approaches Developed for Prognostics on CMAPSS Dataset

    NASA Technical Reports Server (NTRS)

    Ramasso, Emannuel; Saxena, Abhinav

    2014-01-01

    Benchmarking of prognostic algorithms has been challenging due to limited availability of common datasets suitable for prognostics. In an attempt to alleviate this problem several benchmarking datasets have been collected by NASA's prognostic center of excellence and made available to the Prognostics and Health Management (PHM) community to allow evaluation and comparison of prognostics algorithms. Among those datasets are five C-MAPSS datasets that have been extremely popular due to their unique characteristics making them suitable for prognostics. The C-MAPSS datasets pose several challenges that have been tackled by different methods in the PHM literature. In particular, management of high variability due to sensor noise, effects of operating conditions, and presence of multiple simultaneous fault modes are some factors that have great impact on the generalization capabilities of prognostics algorithms. More than 70 publications have used the C-MAPSS datasets for developing data-driven prognostic algorithms. The C-MAPSS datasets are also shown to be well-suited for development of new machine learning and pattern recognition tools for several key preprocessing steps such as feature extraction and selection, failure mode assessment, operating conditions assessment, health status estimation, uncertainty management, and prognostics performance evaluation. This paper summarizes a comprehensive literature review of publications using C-MAPSS datasets and provides guidelines and references to further usage of these datasets in a manner that allows clear and consistent comparison between different approaches.

  19. DEVELOPMENT OF PROCESSING ALGORITHMS FOR OUTLIERS AND MISSING VALUES IN CONSTANT OBSERVATION DATA OF TRAFFIC VOLUMES

    NASA Astrophysics Data System (ADS)

    Hashimoto, Hiroyoshi; Kawano, Tomohiko; Momma, Toshiyuki; Uesaka, Katsumi

    Ministry of Land, Infrastructure, Transport and Tourism of Japan is going to make maximum use of vehicle detectors installed at national roads around the country and efficiently gather traffic volume data from wide areas by estimating traffic volumes within adjacent road sections based on the constant observation data obtained from the vehicle detectors. Efficient processing of outliers and missing values in constant observation data are needed in this process. Focusing on the processing of singular and missing values, the authors have developed a series of algorithms to calculate hourly traffic volumes in which a required accuracy is secured based on measurement data obtained from vehicle detectors. The algorithms have been put to practical uses. The main characteristic of these algorithms is that they use data accumulated in the past as well as data from constant observation devices in adjacent road sections. This paper describes the contents of the developed algorithms and clarifies their accuracy using actual observation data and by making comparis on with other methods.

  20. jClustering, an Open Framework for the Development of 4D Clustering Algorithms

    PubMed Central

    Mateos-Pérez, José María; García-Villalba, Carmen; Pascau, Javier; Desco, Manuel; Vaquero, Juan J.

    2013-01-01

    We present jClustering, an open framework for the design of clustering algorithms in dynamic medical imaging. We developed this tool because of the difficulty involved in manually segmenting dynamic PET images and the lack of availability of source code for published segmentation algorithms. Providing an easily extensible open tool encourages publication of source code to facilitate the process of comparing algorithms and provide interested third parties with the opportunity to review code. The internal structure of the framework allows an external developer to implement new algorithms easily and quickly, focusing only on the particulars of the method being implemented and not on image data handling and preprocessing. This tool has been coded in Java and is presented as an ImageJ plugin in order to take advantage of all the functionalities offered by this imaging analysis platform. Both binary packages and source code have been published, the latter under a free software license (GNU General Public License) to allow modification if necessary. PMID:23990913

  1. Space-based Doppler lidar sampling strategies: Algorithm development and simulated observation experiments

    NASA Technical Reports Server (NTRS)

    Emmitt, G. D.; Wood, S. A.; Morris, M.

    1990-01-01

    Lidar Atmospheric Wind Sounder (LAWS) Simulation Models (LSM) were developed to evaluate the potential impact of global wind observations on the basic understanding of the Earth's atmosphere and on the predictive skills of current forecast models (GCM and regional scale). Fully integrated top to bottom LAWS Simulation Models for global and regional scale simulations were developed. The algorithm development incorporated the effects of aerosols, water vapor, clouds, terrain, and atmospheric turbulence into the models. Other additions include a new satellite orbiter, signal processor, line of sight uncertainty model, new Multi-Paired Algorithm and wind error analysis code. An atmospheric wind field library containing control fields, meteorological fields, phenomena fields, and new European Center for Medium Range Weather Forecasting (ECMWF) data was also added. The LSM was used to address some key LAWS issues and trades such as accuracy and interpretation of LAWS information, data density, signal strength, cloud obscuration, and temporal data resolution.

  2. Neural Networks algorithm development for polarimetric observations of above cloud aerosols (ACA)

    NASA Astrophysics Data System (ADS)

    Segal-Rosenhaimer, M.; Knobelspiesse, K. D.; Redemann, J.

    2015-12-01

    The direct and indirect radiative effects of above clouds aerosols (ACA) are still highly uncertain in current climate assessments. Much of this uncertainty is observational as most orbital remote sensing algorithms were not designed to simultaneously retrieve aerosol and cloud optical properties. Recently, several algorithms have been developed to infer ACA loading and properties using passive, single view angle instruments (OMI, MODIS). Yet, these are not operational and still require rigorous validation. Multiangle polarimetric instruments like POLDER, and RSP show promise for detection and quantification of ACA. However, the retrieval methods for polarimetric measurements entail some drawbacks such as assuming homogeneity of the underlying cloud field for POLDER and retrieved cloud effective radii as an input into RSP scheme. In addition, these methods require computationally expensive RT calculations, which precludes real-time polarimetric data analysis during field campaigns. Here we describe the development of a new algorithm to retrieve atmospheric aerosol and cloud optical properties from observations by polarimetrically sensitive instruments using Neural Networks (NN), which are computationally efficient and fast enough to produce results in the field. This algorithm is specific for ACA, and developed primarily to support the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign, which will acquire measurements of ACA in the South-East Atlantic Ocean during episodes of absorbing aerosols above Stratocumulus cloud decks in 2016-18. The algorithm will use a trained NN scheme for concurrent cloud and aerosol microphysical property retrievals that will be input to optimal estimation method. We will discuss the overall retrieval scheme, focusing on the input variables. Specifically, we use principle component analysis (PCA) to examine the information content available to describe the simulated cloud scenes (with adequate noise

  3. Recommendations for Technology Development and Validation Activities in Support of the Origins Program

    NASA Technical Reports Server (NTRS)

    Capps, Richard W. (Editor)

    1996-01-01

    The Office of Space Science (OSS) has initiated mission concept studies and associated technology roadmapping activities for future large space optical systems. The scientific motivation for these systems is the study of the origins of galaxies, stars, planetary systems and, ultimately, life. Collectively, these studies are part of the 'Astronomical Search for Origins and Planetary Systems Program' or 'Origins Program'. A series of at least three science missions and associated technology validation flights is currently envisioned in the time frame between the year 1999 and approximately 2020. These would be the Space Interferometry Mission (SIM), a 10-meter baseline Michelson stellar interferometer; the Next Generation Space Telescope (NGST), a space-based infrared optimized telescope with aperture diameter larger than four meters; and the Terrestrial Planet Finder (TPF), an 80-meter baseline-nulling Michelson interferometer described in the Exploration of Neighboring Planetary Systems (ExNPS) Study. While all of these missions include significant technological challenges, preliminary studies indicate that the technological requirements are achievable. However, immediate and aggressive technology development is needed. The Office of Space Access and Technology (OSAT) is the primary sponsor of NASA-unique technology for missions such as the Origins series. For some time, the OSAT Space Technology Program has been developing technologies for large space optical systems, including both interferometers and large-aperture telescopes. In addition, technology investments have been made by other NASA programs, including OSS; other government agencies, particularly the Department of Defense; and by the aerospace industrial community. This basis of prior technology investment provides much of the rationale for confidence in the feasibility of the advanced Origins missions. In response to the enhanced interest of both the user community and senior NASA management in large

  4. Development of Outlier detection Algorithm Applicable to a Korean Surge-Gauge

    NASA Astrophysics Data System (ADS)

    Lee, Jun-Whan; Park, Sun-Cheon; Lee, Won-Jin; Lee, Duk Kee

    2016-04-01

    The Korea Meteorological Administration (KMA) is operating a surge-gauge (aerial ultrasonic type) at Ulleung-do to monitor tsunamis. And the National Institute of Meteorological Sciences (NIMS), KMA is developing a tsunami detection and observation system using this surge-gauge. Outliers resulting from a problem with the transmission and extreme events, which change the water level temporarily, are one of the most common discouraging problems in tsunami detection. Unlike a spike, multipoint outliers are difficult to detect clearly. Most of the previous studies used statistic values or signal processing methods such as wavelet transform and filter to detect the multipoint outliers, and used a continuous dataset. However, as the focus moved to a near real-time operation with a dataset that contains gaps, these methods are no longer tenable. In this study, we developed an outlier detection algorithm applicable to the Ulleung-do surge gauge where both multipoint outliers and missing data exist. Although only 9-point data and two arithmetic operations (plus and minus) are used, because of the newly developed keeping method, the algorithm is not only simple and fast but also effective in a non-continuous dataset. We calibrated 17 thresholds and conducted performance tests using the three month data from the Ulleung-do surge gauge. The results show that the newly developed despiking algorithm performs reliably in alleviating the outlier detecting problem.

  5. Sensitivity of cloud retrieval statistics to algorithm choices: Lessons learned from MODIS product development

    NASA Astrophysics Data System (ADS)

    Platnick, Steven; Ackerman, Steven; King, Michael; Zhang, Zhibo; Wind, Galina

    2013-04-01

    Cloud detection algorithms search for measurement signatures that differentiate a cloud-contaminated or "not-clear" pixel from the clear-sky background. These signatures can be spectral, textural or temporal in nature. The magnitude of the difference between the cloud and the background must exceed a threshold value for the pixel to be classified having a not-clear FOV. All detection algorithms employ multiple tests ranging across some portion of the solar reflectance and/or infrared spectrum. However, a cloud is not a single, uniform object, but rather has a distribution of optical thickness and morphology. As a result, problems can arise when the distributions of cloud and clear-sky background characteristics overlap, making some test results indeterminate and/or leading to some amount of detection misclassification. Further, imager cloud retrieval statistics are highly sensitive to how a pixel identified as not-clear by a cloud mask is determined to be useful for cloud-top and optical retrievals based on 1-D radiative models. This presentation provides an overview of the different 'choices' algorithm developers make in cloud detection algorithms and the impact on regional and global cloud amounts and fractional coverage, cloud type and property distributions. Lessons learned over the course of the MODIS cloud product development history are discussed. As an example, we will focus on the 1km MODIS Collection 5 cloud optical retrieval algorithm (product MOD06/MYD06 for Terra and Aqua, respectively) which removed pixels associated with cloud edges as defined by immediate adjacency to clear FOV MODIS cloud mask (MOD35/MYD35) pixels as well as ocean pixels with partly cloudy elements in the 250m MODIS cloud mask - part of the so-called Clear Sky Restoral algorithm. The Collection 6 algorithm attempts retrievals for these two types of partly cloudy pixel populations, but allows a user to isolate or filter out the populations. Retrieval sensitivities for these

  6. MEMS-based sensing and algorithm development for fall detection and gait analysis

    NASA Astrophysics Data System (ADS)

    Gupta, Piyush; Ramirez, Gabriel; Lie, Donald Y. C.; Dallas, Tim; Banister, Ron E.; Dentino, Andrew

    2010-02-01

    Falls by the elderly are highly detrimental to health, frequently resulting in injury, high medical costs, and even death. Using a MEMS-based sensing system, algorithms are being developed for detecting falls and monitoring the gait of elderly and disabled persons. In this study, wireless sensors utilize Zigbee protocols were incorporated into planar shoe insoles and a waist mounted device. The insole contains four sensors to measure pressure applied by the foot. A MEMS based tri-axial accelerometer is embedded in the insert and a second one is utilized by the waist mounted device. The primary fall detection algorithm is derived from the waist accelerometer. The differential acceleration is calculated from samples received in 1.5s time intervals. This differential acceleration provides the quantification via an energy index. From this index one may ascertain different gait and identify fall events. Once a pre-determined index threshold is exceeded, the algorithm will classify an event as a fall or a stumble. The secondary algorithm is derived from frequency analysis techniques. The analysis consists of wavelet transforms conducted on the waist accelerometer data. The insole pressure data is then used to underline discrepancies in the transforms, providing more accurate data for classifying gait and/or detecting falls. The range of the transform amplitude in the fourth iteration of a Daubechies-6 transform was found sufficient to detect and classify fall events.

  7. A Focus Group on Dental Pain Complaints with General Medical Practitioners: Developing a Treatment Algorithm.

    PubMed

    Carter, Ava Elizabeth; Carter, Geoff; Abbey, Robyn

    2016-01-01

    Objective. The differential diagnosis of pain in the mouth can be challenging for general medical practitioners (GMPs) as many different dental problems can present with similar signs and symptoms. This study aimed to create a treatment algorithm for GMPs to effectively and appropriately refer the patients and prescribe antibiotics. Design. The study design is comprised of qualitative focus group discussions. Setting and Subjects. Groups of GMPs within the Gold Coast and Brisbane urban and city regions. Outcome Measures. Content thematically analysed and treatment algorithm developed. Results. There were 5 focus groups with 8-9 participants per group. Addressing whether antibiotics should be given to patients with dental pain was considered very important to GMPs to prevent overtreatment and creating antibiotic resistance. Many practitioners were unsure of what the different forms of dental pains represent. 90% of the practitioners involved agreed that the treatment algorithm was useful to daily practice. Conclusion. Common dental complaints and infections are seldom surgical emergencies but can result in prolonged appointments for those GMPs who do not regularly deal with these issues. The treatment algorithm for referral processes and prescriptions was deemed easily downloadable and simple to interpret and detailed but succinct enough for clinical use by GMPs. PMID:27462469

  8. Dataset exploited for the development and validation of automated cyanobacteria quantification algorithm, ACQUA.

    PubMed

    Gandola, Emanuele; Antonioli, Manuela; Traficante, Alessio; Franceschini, Simone; Scardi, Michele; Congestri, Roberta

    2016-09-01

    The estimation and quantification of potentially toxic cyanobacteria in lakes and reservoirs are often used as a proxy of risk for water intended for human consumption and recreational activities. Here, we present data sets collected from three volcanic Italian lakes (Albano, Vico, Nemi) that present filamentous cyanobacteria strains at different environments. Presented data sets were used to estimate abundance and morphometric characteristics of potentially toxic cyanobacteria comparing manual Vs. automated estimation performed by ACQUA ("ACQUA: Automated Cyanobacterial Quantification Algorithm for toxic filamentous genera using spline curves, pattern recognition and machine learning" (Gandola et al., 2016) [1]). This strategy was used to assess the algorithm performance and to set up the denoising algorithm. Abundance and total length estimations were used for software development, to this aim we evaluated the efficiency of statistical tools and mathematical algorithms, here described. The image convolution with the Sobel filter has been chosen to denoise input images from background signals, then spline curves and least square method were used to parameterize detected filaments and to recombine crossing and interrupted sections aimed at performing precise abundances estimations and morphometric measurements. PMID:27500194

  9. Development of Algorithms for Control of Humidity in Plant Growth Chambers

    NASA Technical Reports Server (NTRS)

    Costello, Thomas A.

    2003-01-01

    Algorithms were developed to control humidity in plant growth chambers used for research on bioregenerative life support at Kennedy Space Center. The algorithms used the computed water vapor pressure (based on measured air temperature and relative humidity) as the process variable, with time-proportioned outputs to operate the humidifier and de-humidifier. Algorithms were based upon proportional-integral-differential (PID) and Fuzzy Logic schemes and were implemented using I/O Control software (OPTO-22) to define and download the control logic to an autonomous programmable logic controller (PLC, ultimate ethernet brain and assorted input-output modules, OPTO-22), which performed the monitoring and control logic processing, as well the physical control of the devices that effected the targeted environment in the chamber. During limited testing, the PLC's successfully implemented the intended control schemes and attained a control resolution for humidity of less than 1%. The algorithms have potential to be used not only with autonomous PLC's but could also be implemented within network-based supervisory control programs. This report documents unique control features that were implemented within the OPTO-22 framework and makes recommendations regarding future uses of the hardware and software for biological research by NASA.

  10. A Focus Group on Dental Pain Complaints with General Medical Practitioners: Developing a Treatment Algorithm

    PubMed Central

    Carter, Geoff; Abbey, Robyn

    2016-01-01

    Objective. The differential diagnosis of pain in the mouth can be challenging for general medical practitioners (GMPs) as many different dental problems can present with similar signs and symptoms. This study aimed to create a treatment algorithm for GMPs to effectively and appropriately refer the patients and prescribe antibiotics. Design. The study design is comprised of qualitative focus group discussions. Setting and Subjects. Groups of GMPs within the Gold Coast and Brisbane urban and city regions. Outcome Measures. Content thematically analysed and treatment algorithm developed. Results. There were 5 focus groups with 8-9 participants per group. Addressing whether antibiotics should be given to patients with dental pain was considered very important to GMPs to prevent overtreatment and creating antibiotic resistance. Many practitioners were unsure of what the different forms of dental pains represent. 90% of the practitioners involved agreed that the treatment algorithm was useful to daily practice. Conclusion. Common dental complaints and infections are seldom surgical emergencies but can result in prolonged appointments for those GMPs who do not regularly deal with these issues. The treatment algorithm for referral processes and prescriptions was deemed easily downloadable and simple to interpret and detailed but succinct enough for clinical use by GMPs. PMID:27462469

  11. Development of AN Algorithmic Procedure for the Detection of Conjugate Fragments

    NASA Astrophysics Data System (ADS)

    Filippas, D.; Georgopoulo, A.

    2013-07-01

    The rapid development of Computer Vision has contributed to the widening of the techniques and methods utilized by archaeologists for the digitization and reconstruction of historic objects by automating the matching of fragments, small or large. This paper proposes a novel method for the detection of conjugate fragments, based mainly on their geometry. Subsequently the application of the Fragmatch algorithm is presented, with an extensive analysis of both of its parts; the global and the partial matching of surfaces. The method proposed is based on the comparison of vectors and surfaces, performed linearly, for simplicity and speed. A series of simulations have been performed in order to test the limits of the algorithm for the noise and the accuracy of scanning, for the number of scan points, as well as for the wear of the surfaces and the diversity of shapes. Problems that have been encountered during the application of these examples are interpreted and ways of dealing with them are being proposed. In addition a practical application is presented to test the algorithm in real conditions. Finally, the key points of this work are being mentioned, followed by an analysis of the advantages and disadvantages of the proposed Fragmatch algorithm along with proposals for future work.

  12. Development of an Aircraft Approach and Departure Atmospheric Profile Generation Algorithm

    NASA Technical Reports Server (NTRS)

    Buck, Bill K.; Velotas, Steven G.; Rutishauser, David K. (Technical Monitor)

    2004-01-01

    In support of NASA Virtual Airspace Modeling and Simulation (VAMS) project, an effort was initiated to develop and test techniques for extracting meteorological data from landing and departing aircraft, and for building altitude based profiles for key meteorological parameters from these data. The generated atmospheric profiles will be used as inputs to NASA s Aircraft Vortex Spacing System (AVOLSS) Prediction Algorithm (APA) for benefits and trade analysis. A Wake Vortex Advisory System (WakeVAS) is being developed to apply weather and wake prediction and sensing technologies with procedures to reduce current wake separation criteria when safe and appropriate to increase airport operational efficiency. The purpose of this report is to document the initial theory and design of the Aircraft Approach Departure Atmospheric Profile Generation Algorithm.

  13. Algorithm developments for the Euler equations with calculations of transonic flows

    NASA Technical Reports Server (NTRS)

    Goorjian, Peter M.

    1987-01-01

    A new algorithm has been developed for the Euler equations that uses flux vector splitting in combination with the concept of rotating the coordinate system to the local streamwise direction. Flux vector biasing is applied along the local streamwise direction and central differencing is used transverse to the flow direction. The flux vector biasing is switched from upwind for supersonic flow to downwind-biased for subsonic flow. This switching is based on the Mach number; hence the proper domain of dependence is used in the supersonic regions and the switching occurs across shock waves. The theoretical basis and the development of the formulas for flux vector splitting are presented. Then several one-dimensional calculations are presented of steady and unsteady transonic flows, which demonstrate the stability and accuracy of the algorithm. Finally results are shown for unsteady transonic flow over an airfoil. The pressure coefficient plots show sharp transonic shock profiles, and the Mach contour plots show smoothly varying contours.

  14. Forecasting of the development of professional medical equipment engineering based on neuro-fuzzy algorithms

    NASA Astrophysics Data System (ADS)

    Vaganova, E. V.; Syryamkin, M. V.

    2015-11-01

    The purpose of the research is the development of evolutionary algorithms for assessments of promising scientific directions. The main attention of the present study is paid to the evaluation of the foresight possibilities for identification of technological peaks and emerging technologies in professional medical equipment engineering in Russia and worldwide on the basis of intellectual property items and neural network modeling. An automated information system consisting of modules implementing various classification methods for accuracy of the forecast improvement and the algorithm of construction of neuro-fuzzy decision tree have been developed. According to the study result, modern trends in this field will focus on personalized smart devices, telemedicine, bio monitoring, «e-Health» and «m-Health» technologies.

  15. Ocean Observations with EOS/MODIS: Algorithm Development and Post Launch Studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1997-01-01

    Significant accomplishments made during the present reporting period are as follows: (1) We developed a new method for identifying the presence of absorbing aerosols and, simultaneously, performing atmospheric correction. The algorithm consists of optimizing the match between the top-of-atmosphere radiance spectrum and the result of models of both the ocean and aerosol optical properties; (2) We developed an algorithm for providing an accurate computation of the diffuse transmittance of the atmosphere given an aerosol model. A module for inclusion into the MODIS atmospheric-correction algorithm was completed; (3) We acquired reflectance data for oceanic whitecaps during a cruise on the RV Ka'imimoana in the Tropical Pacific (Manzanillo, Mexico to Honolulu, Hawaii). The reflectance spectrum of whitecaps was found to be similar to that for breaking waves in the surf zone measured by Frouin, Schwindling and Deschamps, however, the drop in augmented reflectance from 670 to 860 nm was not as great, and the magnitude of the augmented reflectance was significantly less than expected; and (4) We developed a method for the approximate correction for the effects of the MODIS polarization sensitivity. The correction, however, requires adequate characterization of the polarization sensitivity of MODIS prior to launch.

  16. Estimating SWE globally using AMSR-E observations: validation and algorithm development

    NASA Astrophysics Data System (ADS)

    Kelly, R. E.; Foster, J. L.; Hall, D. K.; Tedesco, M.

    2007-12-01

    The Advanced Microwave Scanning Radiometer - EOS (AMSR-E) instrument aboard NASA's Aqua satellite mission is used to estimate daily, five day maximum and monthly average snow water equivalent on a polar projected 25 x 25 km grid. The five-day and monthly products are based on the daily product which uses microwave brightness temperature observations at 10, 18, 36 and 89 GHz, two MODIS land cover products and a snow density "climatology" based on Russian and Canadian data. The current version (B07) of the product implements a dynamic algorithm that has developed from a static approach based on a method by Chang et al. (1987). Retrievals are performed at the native spatial resolution to reflect the measurement "process". This paper describes validation and algorithm developments to the product based on an assessment of the B07 version. New developments to the algorithm that improve the detection capability and that better correct for vegetation are described. The paper also identifies a pathway that will enable the product to reach level 1 validation status.

  17. Development of a Distributed Routing Algorithm for a Digital Telephony Switch.

    NASA Astrophysics Data System (ADS)

    Al-Wakeel, Sami Saleh

    This research has developed a distributed routing algorithm and distributed control software to be implemented in modular digital telephone switching systems. The routing algorithm allows the routing information and the computer calculations for determining the route of switch calls to be divided evenly among the individual units of the digital switch, thus eliminating the need for the centralized complex routing logic. In addition a "routing language" for the storage of routing information has been developed that both compresses the routing information to conserve computer memory and speeds up the search through the routing information. A fully modular microprocessor-based digital switch that takes advantage of the routing algorithm was designed. The switch design achieves several objectives that include the reduction of digital telephone switch cost by taking full advantage of VLSI technology enabling manufacture by developing countries. By utilization of the technical advantages of the distributive routing algorithm, the modular switch can easily reach a capacity of 400,000 lines without degrading the system call processing or exceeding the system loading limits. A distributive control software was also designed to provide the main software protocols and routines necessary for a fully modular telephone switch. The design has several advantages over normal stored program control switches since it eliminates the need for centralized control software and allows the switch units to operate in any signaling environment. As a result, the possibility of total system breakdown is reduced, the switch software can be easily tested or modified, and the switch can interface any of the currently available communication technologies; namely, cable, VHF, satellite, R-1 or R-2 trunks and trunked radio phones. A second development of this research is a mathematical scheme to evaluate the performance of microprocessor-based digital telephone switches. The scheme evaluates various

  18. Developing an Algorithm to Identify History of Cancer Using Electronic Medical Records

    PubMed Central

    Clarke, Christina L.; Feigelson, Heather S.

    2016-01-01

    Introduction/Objective: The objective of this study was to develop an algorithm to identify Kaiser Permanente Colorado (KPCO) members with a history of cancer. Background: Tumor registries are used with high precision to identify incident cancer, but are not designed to capture prevalent cancer within a population. We sought to identify a cohort of adults with no history of cancer, and thus, we could not rely solely on the tumor registry. Methods: We included all KPCO members between the ages of 40–75 years who were continuously enrolled during 2013 (N=201,787). Data from the tumor registry, chemotherapy files, inpatient and outpatient claims were used to create an algorithm to identify members with a high likelihood of cancer. We validated the algorithm using chart review and calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for occurrence of cancer. Findings: The final version of the algorithm achieved a sensitivity of 100 percent and specificity of 84.6 percent for identifying cancer. If we relied on the tumor registry alone, 47 percent of those with a history of cancer would have been missed. Discussion: Using the tumor registry alone to identify a cohort of patients with prior cancer is not sufficient. In the final version of the algorithm, the sensitivity and PPV were improved when a diagnosis code for cancer was required to accompany oncology visits or chemotherapy administration. Conclusion: Electronic medical record (EMR) data can be used effectively in combination with data from the tumor registry to identify health plan members with a history of cancer. PMID:27195308

  19. Development and evaluation of an articulated registration algorithm for human skeleton registration

    NASA Astrophysics Data System (ADS)

    Yip, Stephen; Perk, Timothy; Jeraj, Robert

    2014-03-01

    Accurate registration over multiple scans is necessary to assess treatment response of bone diseases (e.g. metastatic bone lesions). This study aimed to develop and evaluate an articulated registration algorithm for the whole-body skeleton registration in human patients. In articulated registration, whole-body skeletons are registered by auto-segmenting into individual bones using atlas-based segmentation, and then rigidly aligning them. Sixteen patients (weight = 80-117 kg, height = 168-191 cm) with advanced prostate cancer underwent the pre- and mid-treatment PET/CT scans over a course of cancer therapy. Skeletons were extracted from the CT images by thresholding (HU>150). Skeletons were registered using the articulated, rigid, and deformable registration algorithms to account for position and postural variability between scans. The inter-observers agreement in the atlas creation, the agreement between the manually and atlas-based segmented bones, and the registration performances of all three registration algorithms were all assessed using the Dice similarity index—DSIobserved, DSIatlas, and DSIregister. Hausdorff distance (dHausdorff) of the registered skeletons was also used for registration evaluation. Nearly negligible inter-observers variability was found in the bone atlases creation as the DSIobserver was 96 ± 2%. Atlas-based and manual segmented bones were in excellent agreement with DSIatlas of 90 ± 3%. Articulated (DSIregsiter = 75 ± 2%, dHausdorff = 0.37 ± 0.08 cm) and deformable registration algorithms (DSIregister = 77 ± 3%, dHausdorff = 0.34 ± 0.08 cm) considerably outperformed the rigid registration algorithm (DSIregsiter = 59 ± 9%, dHausdorff = 0.69 ± 0.20 cm) in the skeleton registration as the rigid registration algorithm failed to capture the skeleton flexibility in the joints. Despite superior skeleton registration performance, deformable registration algorithm failed to preserve the local rigidity of bones as over 60% of the

  20. Development and evaluation of an articulated registration algorithm for human skeleton registration.

    PubMed

    Yip, Stephen; Perk, Timothy; Jeraj, Robert

    2014-03-21

    Accurate registration over multiple scans is necessary to assess treatment response of bone diseases (e.g. metastatic bone lesions). This study aimed to develop and evaluate an articulated registration algorithm for the whole-body skeleton registration in human patients. In articulated registration, whole-body skeletons are registered by auto-segmenting into individual bones using atlas-based segmentation, and then rigidly aligning them. Sixteen patients (weight = 80-117 kg, height = 168-191 cm) with advanced prostate cancer underwent the pre- and mid-treatment PET/CT scans over a course of cancer therapy. Skeletons were extracted from the CT images by thresholding (HU>150). Skeletons were registered using the articulated, rigid, and deformable registration algorithms to account for position and postural variability between scans. The inter-observers agreement in the atlas creation, the agreement between the manually and atlas-based segmented bones, and the registration performances of all three registration algorithms were all assessed using the Dice similarity index-DSIobserved, DSIatlas, and DSIregister. Hausdorff distance (dHausdorff) of the registered skeletons was also used for registration evaluation. Nearly negligible inter-observers variability was found in the bone atlases creation as the DSIobserver was 96 ± 2%. Atlas-based and manual segmented bones were in excellent agreement with DSIatlas of 90 ± 3%. Articulated (DSIregsiter = 75 ± 2%, dHausdorff = 0.37 ± 0.08 cm) and deformable registration algorithms (DSIregister = 77 ± 3%, dHausdorff = 0.34 ± 0.08 cm) considerably outperformed the rigid registration algorithm (DSIregsiter = 59 ± 9%, dHausdorff = 0.69 ± 0.20 cm) in the skeleton registration as the rigid registration algorithm failed to capture the skeleton flexibility in the joints. Despite superior skeleton registration performance, deformable registration algorithm failed to preserve the local rigidity of bones as over 60% of the skeletons

  1. Development of Analytical Algorithm for the Performance Analysis of Power Train System of an Electric Vehicle

    NASA Astrophysics Data System (ADS)

    Kim, Chul-Ho; Lee, Kee-Man; Lee, Sang-Heon

    Power train system design is one of the key R&D areas on the development process of new automobile because an optimum size of engine with adaptable power transmission which can accomplish the design requirement of new vehicle can be obtained through the system design. Especially, for the electric vehicle design, very reliable design algorithm of a power train system is required for the energy efficiency. In this study, an analytical simulation algorithm is developed to estimate driving performance of a designed power train system of an electric. The principal theory of the simulation algorithm is conservation of energy with several analytical and experimental data such as rolling resistance, aerodynamic drag, mechanical efficiency of power transmission etc. From the analytical calculation results, running resistance of a designed vehicle is obtained with the change of operating condition of the vehicle such as inclined angle of road and vehicle speed. Tractive performance of the model vehicle with a given power train system is also calculated at each gear ratio of transmission. Through analysis of these two calculation results: running resistance and tractive performance, the driving performance of a designed electric vehicle is estimated and it will be used to evaluate the adaptability of the designed power train system on the vehicle.

  2. Algorithm and code development for unsteady three-dimensional Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Obayashi, Shigeru

    1994-01-01

    Aeroelastic tests require extensive cost and risk. An aeroelastic wind-tunnel experiment is an order of magnitude more expensive than a parallel experiment involving only aerodynamics. By complementing the wind-tunnel experiments with numerical simulations, the overall cost of the development of aircraft can be considerably reduced. In order to accurately compute aeroelastic phenomenon it is necessary to solve the unsteady Euler/Navier-Stokes equations simultaneously with the structural equations of motion. These equations accurately describe the flow phenomena for aeroelastic applications. At ARC a code, ENSAERO, is being developed for computing the unsteady aerodynamics and aeroelasticity of aircraft, and it solves the Euler/Navier-Stokes equations. The purpose of this cooperative agreement was to enhance ENSAERO in both algorithm and geometric capabilities. During the last five years, the algorithms of the code have been enhanced extensively by using high-resolution upwind algorithms and efficient implicit solvers. The zonal capability of the code has been extended from a one-to-one grid interface to a mismatching unsteady zonal interface. The geometric capability of the code has been extended from a single oscillating wing case to a full-span wing-body configuration with oscillating control surfaces. Each time a new capability was added, a proper validation case was simulated, and the capability of the code was demonstrated.

  3. Development of an algorithm to predict comfort of wheelchair fit based on clinical measures.

    PubMed

    Kon, Keisuke; Hayakawa, Yasuyuki; Shimizu, Shingo; Nosaka, Toshiya; Tsuruga, Takeshi; Matsubara, Hiroyuki; Nomura, Tomohiro; Murahara, Shin; Haruna, Hirokazu; Ino, Takumi; Inagaki, Jun; Kobayashi, Toshiki

    2015-09-01

    [Purpose] The purpose of this study was to develop an algorithm to predict the comfort of a subject seated in a wheelchair, based on common clinical measurements and without depending on verbal communication. [Subjects] Twenty healthy males (mean age: 21.5 ± 2 years; height: 171 ± 4.3 cm; weight: 56 ± 12.3 kg) participated in this study. [Methods] Each experimental session lasted for 60 min. The clinical measurements were obtained under 4 conditions (good posture, with and without a cushion; bad posture, with and without a cushion). Multiple regression analysis was performed to determine the relationship between a visual analogue scale and exercise physiology parameters (respiratory and metabolism), autonomic nervous parameters (heart rate, blood pressure, and salivary amylase level), and 3D-coordinate posture parameters (good or bad posture). [Results] For the equation (algorithm) to predict the visual analogue scale score, the adjusted multiple correlation coefficient was 0.72, the residual standard deviation was 1.2, and the prediction error was 12%. [Conclusion] The algorithm developed in this study could predict the comfort of healthy male seated in a wheelchair with 72% accuracy. PMID:26504299

  4. Development of an algorithm to predict comfort of wheelchair fit based on clinical measures

    PubMed Central

    Kon, Keisuke; Hayakawa, Yasuyuki; Shimizu, Shingo; Nosaka, Toshiya; Tsuruga, Takeshi; Matsubara, Hiroyuki; Nomura, Tomohiro; Murahara, Shin; Haruna, Hirokazu; Ino, Takumi; Inagaki, Jun; Kobayashi, Toshiki

    2015-01-01

    [Purpose] The purpose of this study was to develop an algorithm to predict the comfort of a subject seated in a wheelchair, based on common clinical measurements and without depending on verbal communication. [Subjects] Twenty healthy males (mean age: 21.5 ± 2 years; height: 171 ± 4.3 cm; weight: 56 ± 12.3 kg) participated in this study. [Methods] Each experimental session lasted for 60 min. The clinical measurements were obtained under 4 conditions (good posture, with and without a cushion; bad posture, with and without a cushion). Multiple regression analysis was performed to determine the relationship between a visual analogue scale and exercise physiology parameters (respiratory and metabolism), autonomic nervous parameters (heart rate, blood pressure, and salivary amylase level), and 3D-coordinate posture parameters (good or bad posture). [Results] For the equation (algorithm) to predict the visual analogue scale score, the adjusted multiple correlation coefficient was 0.72, the residual standard deviation was 1.2, and the prediction error was 12%. [Conclusion] The algorithm developed in this study could predict the comfort of healthy male seated in a wheelchair with 72% accuracy. PMID:26504299

  5. Development of Deterministic Disaggregation Algorithm for Remotely Sensed Soil Moisture Products

    NASA Astrophysics Data System (ADS)

    Shin, Y.; Mohanty, B. P.

    2011-12-01

    Soil moisture near the land surface and in the subsurface profile is an important issue for hydrology, agronomy, and meteorology. Soil moisture data are limited in the spatial and temporal scales. Till now, point-scaled soil moisture measurements representing regional scales are available. Remote sensing (RS) scheme can be an alternative to direct measurement. However, the availability of RS datasets has a limitation due to the scale discrepancy between the RS resolution and local-scale. A number of studies have been conducted to develop downscaling/disaggregation algorithm for extracting fine-scaled soil moisture within a remote sensing product using the stochastic methods. The stochastic downscaling/disaggregation schemes provide us only for soil texture information and sub-area fractions contained in a RS pixel indicating that their specific locations are not recognized. Thus, we developed the deterministic disaggregation algorithm (DDA) with a genetic algorithm (GA) adapting the inverse method for extracting/searching soil textures and their specific location of sub-pixels within a RS soil moisture product under the numerical experiments and field validations. This approach performs quite well in disaggregating/recognizing the soil textures and their specific locations within a RS soil moisture footprint compared to the results of stochastic method. On the basis of these findings, we can suggest that the DDA can be useful for improving the availability of RS products.

  6. An Effort to Develop an Algorithm to Target Abdominal CT Scans for Patients After Gastric Bypass.

    PubMed

    Pernar, Luise I M; Lockridge, Ryan; McCormack, Colleen; Chen, Judy; Shikora, Scott A; Spector, David; Tavakkoli, Ali; Vernon, Ashley H; Robinson, Malcolm K

    2016-10-01

    Abdominal CT (abdCT) scans are frequently ordered for Roux-en-Y gastric bypass (RYGB) patients presenting to the emergency department (ED) with abdominal pain, but often do not reveal intra-abdominal pathology. We aimed to develop an algorithm for rational ordering of abdCTs. We retrospectively reviewed our institution's RYGB patients presenting acutely with abdominal pain, documenting clinical and laboratory data, and scan results. Associations of clinical parameters to abdCT results were examined for outcome predictors. Of 1643 RYGB patients who had surgery between 2005 and 2015, 355 underwent 387 abdCT scans. Based on abdCT, 48 (12 %) patients required surgery and 86 (22 %) another intervention. No clinical or laboratory parameter predicted imaging results. Imaging decisions for RYGB patients do not appear to be amenable to a simple algorithm, and patient work-up should be based on astute clinical judgment.

  7. Ocean Observations with EOS/MODIS: Algorithm Development and Post Launch Studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.; Conboy, Barbara (Technical Monitor)

    1999-01-01

    This separation has been logical thus far; however, as launch of AM-1 approaches, it must be recognized that many of these activities will shift emphasis from algorithm development to validation. For example, the second, third, and fifth bullets will become almost totally validation-focussed activities in the post-launch era, providing the core of our experimental validation effort. Work under the first bullet will continue into the post-launch time frame, driven in part by algorithm deficiencies revealed as a result of validation activities. Prior to the start of the 1999 fiscal year (FY99) we were requested to prepare a brief plan for our FY99 activities. This plan is included as Appendix 1. The present report describes the progress made on our planned activities.

  8. Hybrid Neural-Network: Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics Developed and Demonstrated

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.

    2002-01-01

    As part of the NASA Aviation Safety Program, a unique model-based diagnostics method that employs neural networks and genetic algorithms for aircraft engine performance diagnostics has been developed and demonstrated at the NASA Glenn Research Center against a nonlinear gas turbine engine model. Neural networks are applied to estimate the internal health condition of the engine, and genetic algorithms are used for sensor fault detection, isolation, and quantification. This hybrid architecture combines the excellent nonlinear estimation capabilities of neural networks with the capability to rank the likelihood of various faults given a specific sensor suite signature. The method requires a significantly smaller data training set than a neural network approach alone does, and it performs the combined engine health monitoring objectives of performance diagnostics and sensor fault detection and isolation in the presence of nominal and degraded engine health conditions.

  9. A simulation environment for modeling and development of algorithms for ensembles of mobile microsystems

    NASA Astrophysics Data System (ADS)

    Fink, Jonathan; Collins, Tom; Kumar, Vijay; Mostofi, Yasamin; Baras, John; Sadler, Brian

    2009-05-01

    The vision for the Micro Autonomous Systems Technologies MAST programis to develop autonomous, multifunctional, collaborative ensembles of agile, mobile microsystems to enhance tactical situational awareness in urban and complex terrain for small unit operations. Central to this vision is the ability to have multiple, heterogeneous autonomous assets to function as a single cohesive unit, that is adaptable, responsive to human commands and resilient to adversarial conditions. This paper represents an effort to develop a simulation environment for studying control, sensing, communication, perception, and planning methodologies and algorithms.

  10. Development of a block Lanczos algorithm for free vibration analysis of spinning structures

    NASA Technical Reports Server (NTRS)

    Gupta, K. K.; Lawson, C. L.

    1988-01-01

    This paper is concerned with the development of an efficient eigenproblem solution algorithm and an associated computer program for the economical solution of the free vibration problem of complex practical spinning structural systems. Thus, a detailed description of a newly developed block Lanczos procedure is presented in this paper that employs only real numbers in all relevant computations and also fully exploits sparsity of associated matrices. The procedure is capable of computing multiple roots and proves to be most efficient compared to other existing similar techniques.

  11. Development of a memetic clustering algorithm for optimal spectral histology: application to FTIR images of normal human colon.

    PubMed

    Farah, Ihsen; Nguyen, Thi Nguyet Que; Groh, Audrey; Guenot, Dominique; Jeannesson, Pierre; Gobinet, Cyril

    2016-05-23

    The coupling between Fourier-transform infrared (FTIR) imaging and unsupervised classification is effective in revealing the different structures of human tissues based on their specific biomolecular IR signatures; thus the spectral histology of the studied samples is achieved. However, the most widely applied clustering methods in spectral histology are local search algorithms, which converge to a local optimum, depending on initialization. Multiple runs of the techniques estimate multiple different solutions. Here, we propose a memetic algorithm, based on a genetic algorithm and a k-means clustering refinement, to perform optimal clustering. In addition, this approach was applied to the acquired FTIR images of normal human colon tissues originating from five patients. The results show the efficiency of the proposed memetic algorithm to achieve the optimal spectral histology of these samples, contrary to k-means. PMID:27110605

  12. Development of ichthyosporeans sheds light on the origin of metazoan multicellularity.

    PubMed

    Suga, Hiroshi; Ruiz-Trillo, Iñaki

    2013-05-01

    To understand the mechanisms involved in the transition from protists to multicellular animals (metazoans), studying unicellular relatives of metazoans is as important as studying metazoans themselves. However, investigations remain poor on the closest unicellular (or colonial) relatives of Metazoa, i.e., choanoflagellates, filastereans and ichthyosporeans. Molecular-level analyses on these protists have been severely limited by the lack of transgenesis tools. Their genomes, however, contain several key genes encoding proteins important for metazoan development and multicellularity, including those involved in cell-cell communication, cell proliferation, cell differentiation, and tissue growth control. Tools to analyze their functions in a molecular level are awaited. Here we report techniques of cell transformation and gene silencing developed for the first time in a close relative of metazoans, the ichthyosporean Creolimax fragrantissima. We propose C. fragrantissima as a model organism to investigate the origin of metazoan multicellularity. By transgenesis, we demonstrate that its colony develops from a fully-grown multinucleate syncytium, in which nuclear divisions are strictly synchronized. It has been hypothesized that metazoan multicellular development initially occurred in the course of evolution through successive rounds of cell division, which were not necessarily be synchronized, or alternatively through cell aggregation. Our findings point to another possible mechanism for the evolution of animal multicellularity, namely, cellularization of a syncytium in which nuclear divisions are synchronized. We believe that further studies on the development of ichthyosporeans by the use of our methodologies will provide novel insights into the origin of metazoan multicellularity.

  13. Developments of global greenhouse gas retrieval algorithm based on Optimal Estimation Method

    NASA Astrophysics Data System (ADS)

    Kim, W. V.; Kim, J.; Lee, H.; Jung, Y.; Boesch, H.

    2013-12-01

    After the industrial revolution, atmospheric carbon dioxide concentration increased drastically over the last 250 years. It is still increasing and over than 400ppm of carbon dioxide was measured at Mauna Loa observatory for the first time which value was considered as important milestone. Therefore, understanding the source, emission, transport and sink of global carbon dioxide is unprecedentedly important. Currently, Total Carbon Column Observing Network (TCCON) is operated to observe CO2 concentration by ground base instruments. However, the number of site is very few and concentrated to Europe and North America. Remote sensing of CO2 could supplement those limitations. Greenhouse Gases Observing SATellite (GOSAT) which was launched 2009 is measuring column density of CO2 and other satellites are planned to launch in a few years. GOSAT provide valuable measurement data but its low spatial resolution and poor success rate of retrieval due to aerosol and cloud, forced the results to cover less than half of the whole globe. To improve data availability, accurate aerosol information is necessary, especially for East Asia region where the aerosol concentration is higher than other region. For the first step, we are developing CO2 retrieval algorithm based on optimal estimation method with VLIDORT the vector discrete ordinate radiative transfer model. Proto type algorithm, developed from various combinations of state vectors to find best combination of state vectors, shows appropriate result and good agreement with TCCON measurements. To reduce calculation cost low-stream interpolation is applied for model simulation and the simulation time is drastically reduced. For the further study, GOSAT CO2 retrieval algorithm will be combined with accurate GOSAT-CAI aerosol retrieval algorithm to obtain more accurate result especially for East Asia.

  14. Status of GCOM-W1/AMSR2 development, algorithms, and products

    NASA Astrophysics Data System (ADS)

    Maeda, Takashi; Imaoka, Keiji; Kachi, Misako; Fujii, Hideyuki; Shibata, Akira; Naoki, Kazuhiro; Kasahara, Marehito; Ito, Norimasa; Nakagawa, Keizo; Oki, Taikan

    2011-11-01

    The Global Change Observation Mission (GCOM) consists of two polar orbiting satellite observing systems, GCOM-W (Water) and GCOM-C (Climate), and three generations to achieve global and long-term monitoring of the Earth. GCOM-W1 is the first satellite of the GCOM-W series and scheduled to be launched in Japanese fiscal year 2011. The Advanced Microwave Scanning Radiometer-2 (AMSR2) will be the mission instrument of GCOM-W1. AMSR2 will extend the observation of currently ongoing AMSR-E on EOS Aqua platform. Development of GCOM-W1 and AMSR2 is progressing on schedule. Proto-flight test (PFT) of AMSR2 was completed and delivered to the GCOM-W1 satellite system. Currently, the GCOM-W1 system is under PFT at Tsukuba Space Center until summer 2011 before shipment to launch site, Tanegashima Space Center. Development of retrieval algorithms has been also progressing with the collaboration of the principal investigators. Based on the algorithm comparison results, at-launch standard algorithms were selected and implemented into the processing system. These algorithms will be validated and updated during the initial calibration and validation phase. As an instrument calibration activity, a deep space calibration maneuver is planned during the initial checkout phase, to confirm the consistency of cold sky calibration and intra-scan biases. Maintaining and expanding the validation sites are also ongoing activities. A flux tower observing instruments will be introduced into the Murray-Darling basin in Australia, where the validation of other soil moisture instruments (e.g., SMOS and SMAP) is planned.

  15. The development of line-scan image recognition algorithms for the detection of frass on mature tomatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this research, a multispectral algorithm derived from hyperspectral line-scan fluorescence imaging under violet LED excitation was developed for the detection of frass contamination on mature tomatoes. The algorithm utilized the fluorescence intensities at two wavebands, 664 nm and 690 nm, for co...

  16. Algorithm development and verification of UASCM for multi-dimension and multi-group neutron kinetics model

    SciTech Connect

    Si, S.

    2012-07-01

    The Universal Algorithm of Stiffness Confinement Method (UASCM) for neutron kinetics model of multi-dimensional and multi-group transport equations or diffusion equations has been developed. The numerical experiments based on transport theory code MGSNM and diffusion theory code MGNEM have demonstrated that the algorithm has sufficient accuracy and stability. (authors)

  17. Microphysical particle properties derived from inversion algorithms developed in the framework of EARLINET

    NASA Astrophysics Data System (ADS)

    Müller, Detlef; Böckmann, Christine; Kolgotin, Alexei; Schneidenbach, Lars; Chemyakin, Eduard; Rosemann, Julia; Znak, Pavel; Romanov, Anton

    2016-10-01

    We present a summary on the current status of two inversion algorithms that are used in EARLINET (European Aerosol Research Lidar Network) for the inversion of data collected with EARLINET multiwavelength Raman lidars. These instruments measure backscatter coefficients at 355, 532, and 1064 nm, and extinction coefficients at 355 and 532 nm. Development of these two algorithms started in 2000 when EARLINET was founded. The algorithms are based on a manually controlled inversion of optical data which allows for detailed sensitivity studies. The algorithms allow us to derive particle effective radius as well as volume and surface area concentration with comparably high confidence. The retrieval of the real and imaginary parts of the complex refractive index still is a challenge in view of the accuracy required for these parameters in climate change studies in which light absorption needs to be known with high accuracy. It is an extreme challenge to retrieve the real part with an accuracy better than 0.05 and the imaginary part with accuracy better than 0.005-0.1 or ±50 %. Single-scattering albedo can be computed from the retrieved microphysical parameters and allows us to categorize aerosols into high- and low-absorbing aerosols. On the basis of a few exemplary simulations with synthetic optical data we discuss the current status of these manually operated algorithms, the potentially achievable accuracy of data products, and the goals for future work. One algorithm was used with the purpose of testing how well microphysical parameters can be derived if the real part of the complex refractive index is known to at least 0.05 or 0.1. The other algorithm was used to find out how well microphysical parameters can be derived if this constraint for the real part is not applied. The optical data used in our study cover a range of Ångström exponents and extinction-to-backscatter (lidar) ratios that are found from lidar measurements of various aerosol types. We also tested

  18. A collaborative approach to developing an electronic health record phenotyping algorithm for drug-induced liver injury

    PubMed Central

    Overby, Casey Lynnette; Pathak, Jyotishman; Gottesman, Omri; Haerian, Krystl; Perotte, Adler; Murphy, Sean; Bruce, Kevin; Johnson, Stephanie; Talwalkar, Jayant; Shen, Yufeng; Ellis, Steve; Kullo, Iftikhar; Chute, Christopher; Friedman, Carol; Bottinger, Erwin; Hripcsak, George; Weng, Chunhua

    2013-01-01

    Objective To describe a collaborative approach for developing an electronic health record (EHR) phenotyping algorithm for drug-induced liver injury (DILI). Methods We analyzed types and causes of differences in DILI case definitions provided by two institutions—Columbia University and Mayo Clinic; harmonized two EHR phenotyping algorithms; and assessed the performance, measured by sensitivity, specificity, positive predictive value, and negative predictive value, of the resulting algorithm at three institutions except that sensitivity was measured only at Columbia University. Results Although these sites had the same case definition, their phenotyping methods differed by selection of liver injury diagnoses, inclusion of drugs cited in DILI cases, laboratory tests assessed, laboratory thresholds for liver injury, exclusion criteria, and approaches to validating phenotypes. We reached consensus on a DILI phenotyping algorithm and implemented it at three institutions. The algorithm was adapted locally to account for differences in populations and data access. Implementations collectively yielded 117 algorithm-selected cases and 23 confirmed true positive cases. Discussion Phenotyping for rare conditions benefits significantly from pooling data across institutions. Despite the heterogeneity of EHRs and varied algorithm implementations, we demonstrated the portability of this algorithm across three institutions. The performance of this algorithm for identifying DILI was comparable with other computerized approaches to identify adverse drug events. Conclusions Phenotyping algorithms developed for rare and complex conditions are likely to require adaptive implementation at multiple institutions. Better approaches are also needed to share algorithms. Early agreement on goals, data sources, and validation methods may improve the portability of the algorithms. PMID:23837993

  19. Development and evaluation of collision warning/collision avoidance algorithms using an errable driver model

    NASA Astrophysics Data System (ADS)

    Yang, Hsin-Hsiang; Peng, Huei

    2010-12-01

    Collision warning/collision avoidance (CW/CA) systems must be designed to work seamlessly with a human driver, providing warning or control actions when the driver's response (or lack of) is deemed inappropriate. The effectiveness of CW/CA systems working with a human driver needs to be evaluated thoroughly because of legal/liability and other (e.g. traffic flow) concerns. CW/CA systems tuned only under open-loop manoeuvres were frequently found to work unsatisfactorily with human-in-the-loop. However, tuning CW/CA systems with human drivers co-existing is slow and non-repeatable. Driver models, if constructed and used properly, can capture human/control interactions and accelerate the CW/CA development process. Design and evaluation methods for CW/CA algorithms can be categorised into three approaches, scenario-based, performance-based and human-centred. The strength and weakness of these approaches were discussed in this paper and a humanised errable driver model was introduced to improve the developing process. The errable driver model used in this paper is a model that emulates human driver's functions and can generate both nominal (error-free) and devious (with error) behaviours. The car-following data used for developing and validating the model were obtained from a large-scale naturalistic driving database. Three error-inducing behaviours were introduced: human perceptual limitation, time delay and distraction. By including these error-inducing behaviours, rear-end collisions with a lead vehicle were found to occur at a probability similar to traffic accident statistics in the USA. This driver model is then used to evaluate the performance of several existing CW/CA algorithms. Finally, a new CW/CA algorithm was developed based on this errable driver model.

  20. Development of algorithms for understanding the temporal and spatial variability of the earth's radiation balance

    NASA Astrophysics Data System (ADS)

    Brooks, D. R.; Harrison, E. F.; Minnis, P.; Suttles, J. T.; Kandel, R. S.

    1986-05-01

    A brief description is given of how temporal and spatial variability in the earth's radiative behavior influences the goals of satellite radiation monitoring systems and how some previous systems have addressed the existing problems. Then, results of some simulations of radiation budget monitoring missions are presented. These studies led to the design of the Earth Radiation Budget Experiment (ERBE). A description is given of the temporal and spatial averaging algorithms developed for the ERBE data analysis. These algorithms are intended primarily to produce monthly averages of the net radiant exitance on regional, zonal, and global scales and to provide insight into the regional diurnal variability of radiative parameters such as albedo and long-wave radiant exitance. The algorithms are applied to scanner and nonscanner data for up to three satellites. Modeling of dialy shortwave albedo and radiant exitance with satellite samling that is insufficient to fully account for changing meteorology is discussed in detail. Studies performed during the ERBE mission and software design are reviewed. These studies provide quantitative estimates of the effects of temporally sparse and biased sampling on inferred diurnal and regional radiative parameters. Other topics covered include long-wave diurnal modeling, extraction of a regional monthly net clear-sky radiation budget, the statistical significance of observed diurnal variability, quality control of the analysis, and proposals for validating the results of ERBE time and space averaging.

  1. GLASS daytime all-wave net radiation product: Algorithm development and preliminary validation

    DOE PAGES

    Jiang, Bo; Liang, Shunlin; Ma, Han; Zhang, Xiaotong; Xiao, Zhiqiang; Zhao, Xiang; Jia, Kun; Yao, Yunjun; Jia, Aolin

    2016-03-09

    Mapping surface all-wave net radiation (Rn) is critically needed for various applications. Several existing Rn products from numerical models and satellite observations have coarse spatial resolutions and their accuracies may not meet the requirements of land applications. In this study, we develop the Global LAnd Surface Satellite (GLASS) daytime Rn product at a 5 km spatial resolution. Its algorithm for converting shortwave radiation to all-wave net radiation using the Multivariate Adaptive Regression Splines (MARS) model is determined after comparison with three other algorithms. The validation of the GLASS Rn product based on high-quality in situ measurements in the United Statesmore » shows a coefficient of determination value of 0.879, an average root mean square error value of 31.61 Wm-2, and an average bias of 17.59 Wm-2. Furthermore, we also compare our product/algorithm with another satellite product (CERES-SYN) and two reanalysis products (MERRA and JRA55), and find that the accuracy of the much higher spatial resolution GLASS Rn product is satisfactory. The GLASS Rn product from 2000 to the present is operational and freely available to the public.« less

  2. Development of a general learning algorithm with applications in nuclear reactor systems

    SciTech Connect

    Brittain, C.R.; Otaduy, P.J.; Perez, R.B.

    1989-12-01

    The objective of this study was development of a generalized learning algorithm that can learn to predict a particular feature of a process by observation of a set of representative input examples. The algorithm uses pattern matching and statistical analysis techniques to find a functional relationship between descriptive attributes of the input examples and the feature to be predicted. The algorithm was tested by applying it to a set of examples consisting of performance descriptions for 277 fuel cycles of Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR). The program learned to predict the critical rod position for the HFIR from core configuration data prior to reactor startup. The functional relationship bases its predictions on initial core reactivity, the number of certain targets placed in the center of the reactor, and the total exposure of the control plates. Twelve characteristic fuel cycle clusters were identified. Nine fuel cycles were diagnosed as having noisy data, and one could not be predicted by the functional relationship. 13 refs., 6 figs.

  3. Development of a new time domain-based algorithm for train detection and axle counting

    NASA Astrophysics Data System (ADS)

    Allotta, B.; D'Adamio, P.; Meli, E.; Pugi, L.

    2015-12-01

    This paper presents an innovative train detection algorithm, able to perform the train localisation and, at the same time, to estimate its speed, the crossing times on a fixed point of the track and the axle number. The proposed solution uses the same approach to evaluate all these quantities, starting from the knowledge of generic track inputs directly measured on the track (for example, the vertical forces on the sleepers, the rail deformation and the rail stress). More particularly, all the inputs are processed through cross-correlation operations to extract the required information in terms of speed, crossing time instants and axle counter. This approach has the advantage to be simple and less invasive than the standard ones (it requires less equipment) and represents a more reliable and robust solution against numerical noise because it exploits the whole shape of the input signal and not only the peak values. A suitable and accurate multibody model of railway vehicle and flexible track has also been developed by the authors to test the algorithm when experimental data are not available and in general, under any operating conditions (fundamental to verify the algorithm accuracy and robustness). The railway vehicle chosen as benchmark is the Manchester Wagon, modelled in the Adams VI-Rail environment. The physical model of the flexible track has been implemented in the Matlab and Comsol Multiphysics environments. A simulation campaign has been performed to verify the performance and the robustness of the proposed algorithm, and the results are quite promising. The research has been carried out in cooperation with Ansaldo STS and ECM Spa.

  4. Development and Validation of a Diabetic Retinopathy Referral Algorithm Based on Single-Field Fundus Photography

    PubMed Central

    Srinivasan, Sangeetha; Shetty, Sharan; Natarajan, Viswanathan; Sharma, Tarun; Raman, Rajiv

    2016-01-01

    Purpose To develop a simplified algorithm to identify and refer diabetic retinopathy (DR) from single-field retinal images specifically for sight-threatening diabetic retinopathy for appropriate care (ii) to determine the agreement and diagnostic accuracy of the algorithm as a pilot study among optometrists versus “gold standard” (retinal specialist grading). Methods The severity of DR was scored based on colour photo using a colour coded algorithm, which included the lesions of DR and number of quadrants involved. A total of 99 participants underwent training followed by evaluation. Data of the 99 participants were analyzed. Fifty posterior pole 45 degree retinal images with all stages of DR were presented. Kappa scores (κ), areas under the receiver operating characteristic curves (AUCs), sensitivity and specificity were determined, with further comparison between working optometrists and optometry students. Results Mean age of the participants was 22 years (range: 19–43 years), 87% being women. Participants correctly identified 91.5% images that required immediate referral (κ) = 0.696), 62.5% of images as requiring review after 6 months (κ = 0.462), and 51.2% of those requiring review after 1 year (κ = 0.532). The sensitivity and specificity of the optometrists were 91% and 78% for immediate referral, 62% and 84% for review after 6 months, and 51% and 95% for review after 1 year, respectively. The AUC was the highest (0.855) for immediate referral, second highest (0.824) for review after 1 year, and 0.727 for review after 6 months criteria. Optometry students performed better than the working optometrists for all grades of referral. Conclusions The diabetic retinopathy algorithm assessed in this work is a simple and a fairly accurate method for appropriate referral based on single-field 45 degree posterior pole retinal images. PMID:27661981

  5. The origin and development of the immune system with a view to stem cell therapy.

    PubMed

    Anastassova-Kristeva, Marlene

    2003-04-01

    Careful study of the phylogeny and ontogeny of the three components of the immune system reveals that the macrophage, lymphatic, and hematopoietic systems originate independently of each other. Chronologically, the most ancient is the macrophage system, which arises in the coelomic cavity as mesenchymal ameboid cells having the properties to recognize self from non-self and to ingest foreign particles. The lymphatic system later develops from the endoderm of pharyngeal pouches, where the thymic anlage differentiates. The lymphocytes that originate here seed all lymphatic organs and retain the ability to divide and thereby form multiple colonies (lymphatic nodules) in the respiratory and digestive tract; further diversification of lymphocytes follows after confrontation with antigens. The last component of the immune system to appear is the hematopoietic system, which originates from the splanchnic mesoderm of the yolk sac as hematogenic tissue, containing hemangioblasts. The hematogenic tissue remains attached to the outer wall of the vitelline vessels, which provides an efficient mechanism for introducing the hematogenic tissue into the embryo. In an appropriate microenvironment, the hemangioblasts give rise to sinusoidal endothelium and to hemocytoblasts - the bone marrow stem cells for erythrocytes, myeloid cells, and megakaryocytes. The facts and opinions presented in this article are not in agreement with the currently accepted dogma that a common "hematolymphatic stem cell" localized in the marrow generates all of the cellular components of blood and the immune system.

  6. Development of Bio-Optical Algorithms for Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Ryu, J.; Moon, J.; Min, J.; Palanisamy, S.; Han, H.; Ahn, Y.

    2007-12-01

    GOCI, the first Geostationary Ocean Color Imager, shall be operated in a staring-frame capture mode onboard its Communication Ocean and Meteorological Satellite (COMS) and tentatively scheduled for launch in 2008. The mission concept includes eight visible-to-near-infrared bands, 0.5 km pixel resolution, and a coverage region of 2,500 ¢®¢¯ 2,500 km centered at Korea. The GOCI is expected to provide SeaWiFS quality observations for a single study area with imaging interval of 1 hour from 10 am to 5 pm. In the GOCI swath area, the optical properties of the East Sea (typical of Case-I water), the Yellow Sea and East China Sea (typical of Case-II water) are investigated. For developing the GOCI bio-optical algorithms in optically more complex waters, it is necessary to study and understand the optical properties around the Korean Sea. Radiometric measurements were made using WETLabs AC-S, TriOS RAMSES ACC/ARC, and ASD FieldSpec Pro Dual VNIR Spectroradiometer. Seawater samples were collected concurrently with the radiometric measurements at about 300 points around the Korean Sea during 1998 to 2007. The absorption coefficients were determined using Perkin-Elmer Lambda 19 dual-beam spectrophotometer. We analyzed the absorption coefficient of sea water constituents such as phytoplankton, Suspended Sediment (SS) and Dissolved Organic Matter (DOM). Two kinds of chlorophyll algorithms are developed by using statistical regression and fluorescence-based technique considering the bio- optical properties in Case-II waters. Fluorescence measurements were related to in situ Chl-a concentrations to obtain the Flu(681), Flu(688) and Flu(area) algorithms, which were compared with those from standard spectral ratios of the remote sensing reflectance. The single band algorithm for is derived by relationship between Rrs (555) and in situ concentration. The CDOM is estimated by absorption spectra and its slope centered at 440 nm wavelength. These standard algorithms will be

  7. Origine et developpement des industries de la langue (Origin and Development of Language Utilities). Publication K-8.

    ERIC Educational Resources Information Center

    L'Homme, Marie-Claude

    The evolution of "language utilities," a concept confined largely to the francophone world and relating to the uses of language in computer science and the use of computer science for languages, is chronicled. The language utilities are of three types: (1) tools for language development, primarily dictionary databases and related tools; (2) tools…

  8. [Biological problems of origin and development of various physiological functions (theory and application)].

    PubMed

    Ivanov, K P

    2001-01-01

    The author presents some idea about origin and development of some physiological functions: outer breathing, breath function of blood, blood circulation, thermoregulation, energy supply. The conclusions about main directions of evolution of these functions and duration of their development in phylogeny were drawn. The author gave some examples of abrupt changes of development of these functions in different groups of animals and discussed possible reasons of such changes. General quantitative estimation of the results of evolution of these functions from the position of their summArized efficiency was done. Quantitative characteristics of optimization and efficiency limits of physiological functions were suggested on the base of new data in general biology and comparative physiology. The author put toward the hypothesis about conventional "mistakes" of evolution and showed deep biological reasons of some seriOus illness. The examples of some applied problems in biology, physiology and medicine that can be solved with the data on evolution of physiological functions are presented. PMID:11548400

  9. Initiation and development of first lightning leader: The effects of coronae and position of lightning origin

    NASA Astrophysics Data System (ADS)

    Aleksandrov, N. L.; Bazelyan, E. M.; Raizer, Yu. P.

    2005-07-01

    This paper addresses, by means of numerical simulations, the issues of lightning initiation near tall, grounded objects and lightning development in the cloud-to-ground gap. Taken into account is the effect of coronae on the initiation of an upward leader from the top of a fixed grounded structure that is exposed to the electric field produced by the storm-cloud and approaching downward leader. It is shown that the potential carried by a downward leader to the ground and, consequently, the return stroke current depend greatly on the position of a bi-directional leader origin inside a cloud and on the shape of the leader path.

  10. Geochemical background values for trace elements in arable soils developed from sedimentary rocks of glacial origin.

    PubMed

    Czarnowska, K; Gworek, B

    1990-12-01

    The total content of trace elements was examined in some arable soils developed from boulder loam and silt formations of the Middle Poland and Baltic glaciations (62 profiles). Mean element concentrations calculated on the basis of chemical and statistical analyses were as follows: Mn = 322; Zn = 36; Cr = 30; Ni = 12.7; Pb = 10.3; Cu = 8.8; Co = 4.7; and Cd = 0.27 in mg kg(-1) of soil dry weight. The authors propose to accept these figures as the geochemical background values for soils derived from sedimentary rocks of glacial origin.

  11. An Illustrated Overview of the Origins and Development of the QSCP Meetings

    NASA Astrophysics Data System (ADS)

    Maruani, Jean

    The origins and development of the QSCP meetings are recalled: from a congress organized in Paris in 1986 to honour Prof. Raymond Daudel, through Franco-Bulgarian cooperation between various teams then European contracts, in the frame of COST projects, involving a network of French, Spanish, British, Italian, Swedish, and Bulgarian scientists, till the holding of the first QSCP workshop near Pisa in 1996 to honour Prof. Stefan Christov. After that there was a meeting every year, always with proceedings published. This historical overview will be presented as an illustrated journey in picturesque cities of Western and Eastern Europe, North Africa, and North America, sprinkled with historical or philosophical anecdotes and insights.

  12. Development of Algorithms and Error Analyses for the Short Baseline Lightning Detection and Ranging System

    NASA Technical Reports Server (NTRS)

    Starr, Stanley O.

    1998-01-01

    NASA, at the John F. Kennedy Space Center (KSC), developed and operates a unique high-precision lightning location system to provide lightning-related weather warnings. These warnings are used to stop lightning- sensitive operations such as space vehicle launches and ground operations where equipment and personnel are at risk. The data is provided to the Range Weather Operations (45th Weather Squadron, U.S. Air Force) where it is used with other meteorological data to issue weather advisories and warnings for Cape Canaveral Air Station and KSC operations. This system, called Lightning Detection and Ranging (LDAR), provides users with a graphical display in three dimensions of 66 megahertz radio frequency events generated by lightning processes. The locations of these events provide a sound basis for the prediction of lightning hazards. This document provides the basis for the design approach and data analysis for a system of radio frequency receivers to provide azimuth and elevation data for lightning pulses detected simultaneously by the LDAR system. The intent is for this direction-finding system to correct and augment the data provided by LDAR and, thereby, increase the rate of valid data and to correct or discard any invalid data. This document develops the necessary equations and algorithms, identifies sources of systematic errors and means to correct them, and analyzes the algorithms for random error. This data analysis approach is not found in the existing literature and was developed to facilitate the operation of this Short Baseline LDAR (SBLDAR). These algorithms may also be useful for other direction-finding systems using radio pulses or ultrasonic pulse data.

  13. Development of a Smart Release Algorithm for Mid-Air Separation of Parachute Test Articles

    NASA Technical Reports Server (NTRS)

    Moore, James W.

    2011-01-01

    The Crew Exploration Vehicle Parachute Assembly System (CPAS) project is currently developing an autonomous method to separate a capsule-shaped parachute test vehicle from an air-drop platform for use in the test program to develop and validate the parachute system for the Orion spacecraft. The CPAS project seeks to perform air-drop tests of an Orion-like boilerplate capsule. Delivery of the boilerplate capsule to the test condition has proven to be a critical and complicated task. In the current concept, the boilerplate vehicle is extracted from an aircraft on top of a Type V pallet and then separated from the pallet in mid-air. The attitude of the vehicles at separation is critical to avoiding re-contact and successfully deploying the boilerplate into a heatshield-down orientation. Neither the pallet nor the boilerplate has an active control system. However, the attitude of the mated vehicle as a function of time is somewhat predictable. CPAS engineers have designed an avionics system to monitor the attitude of the mated vehicle as it is extracted from the aircraft and command a release when the desired conditions are met. The algorithm includes contingency capabilities designed to release the test vehicle before undesirable orientations occur. The algorithm was verified with simulation and ground testing. The pre-flight development and testing is discussed and limitations of ground testing are noted. The CPAS project performed a series of three drop tests as a proof-of-concept of the release technique. These tests helped to refine the attitude instrumentation and software algorithm to be used on future tests. The drop tests are described in detail and the evolution of the release system with each test is described.

  14. Developing a Direct Search Algorithm for Solving the Capacitated Open Vehicle Routing Problem

    NASA Astrophysics Data System (ADS)

    Simbolon, Hotman

    2011-06-01

    In open vehicle routing problems, the vehicles are not required to return to the depot after completing service. In this paper, we present the first exact optimization algorithm for the open version of the well-known capacitated vehicle routing problem (CVRP). The strategy of releasing nonbasic variables from their bounds, combined with the "active constraint" method and the notion of superbasics, has been developed for efficiently requirements; this strategy is used to force the appropriate non-integer basic variables to move to their neighborhood integer points. A study of criteria for choosing a nonbasic variable to work with in the integerizing strategy has also been made.

  15. Multidisciplinary Design, Analysis, and Optimization Tool Development using a Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Li, Wesley

    2008-01-01

    Multidisciplinary design, analysis, and optimization using a genetic algorithm is being developed at the National Aeronautics and Space A dministration Dryden Flight Research Center to automate analysis and design process by leveraging existing tools such as NASTRAN, ZAERO a nd CFD codes to enable true multidisciplinary optimization in the pr eliminary design stage of subsonic, transonic, supersonic, and hypers onic aircraft. This is a promising technology, but faces many challe nges in large-scale, real-world application. This paper describes cur rent approaches, recent results, and challenges for MDAO as demonstr ated by our experience with the Ikhana fire pod design.

  16. Multidisciplinary Design, Analysis, and Optimization Tool Development Using a Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Li, Wesley

    2009-01-01

    Multidisciplinary design, analysis, and optimization using a genetic algorithm is being developed at the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) to automate analysis and design process by leveraging existing tools to enable true multidisciplinary optimization in the preliminary design stage of subsonic, transonic, supersonic, and hypersonic aircraft. This is a promising technology, but faces many challenges in large-scale, real-world application. This report describes current approaches, recent results, and challenges for multidisciplinary design, analysis, and optimization as demonstrated by experience with the Ikhana fire pod design.!

  17. Developing a data element repository to support EHR-driven phenotype algorithm authoring and execution.

    PubMed

    Jiang, Guoqian; Kiefer, Richard C; Rasmussen, Luke V; Solbrig, Harold R; Mo, Huan; Pacheco, Jennifer A; Xu, Jie; Montague, Enid; Thompson, William K; Denny, Joshua C; Chute, Christopher G; Pathak, Jyotishman

    2016-08-01

    The Quality Data Model (QDM) is an information model developed by the National Quality Forum for representing electronic health record (EHR)-based electronic clinical quality measures (eCQMs). In conjunction with the HL7 Health Quality Measures Format (HQMF), QDM contains core elements that make it a promising model for representing EHR-driven phenotype algorithms for clinical research. However, the current QDM specification is available only as descriptive documents suitable for human readability and interpretation, but not for machine consumption. The objective of the present study is to develop and evaluate a data element repository (DER) for providing machine-readable QDM data element service APIs to support phenotype algorithm authoring and execution. We used the ISO/IEC 11179 metadata standard to capture the structure for each data element, and leverage Semantic Web technologies to facilitate semantic representation of these metadata. We observed there are a number of underspecified areas in the QDM, including the lack of model constraints and pre-defined value sets. We propose a harmonization with the models developed in HL7 Fast Healthcare Interoperability Resources (FHIR) and Clinical Information Modeling Initiatives (CIMI) to enhance the QDM specification and enable the extensibility and better coverage of the DER. We also compared the DER with the existing QDM implementation utilized within the Measure Authoring Tool (MAT) to demonstrate the scalability and extensibility of our DER-based approach. PMID:27392645

  18. Development and evaluation of a predictive algorithm for telerobotic task complexity

    NASA Technical Reports Server (NTRS)

    Gernhardt, M. L.; Hunter, R. C.; Hedgecock, J. C.; Stephenson, A. G.

    1993-01-01

    There is a wide range of complexity in the various telerobotic servicing tasks performed in subsea, space, and hazardous material handling environments. Experience with telerobotic servicing has evolved into a knowledge base used to design tasks to be 'telerobot friendly.' This knowledge base generally resides in a small group of people. Written documentation and requirements are limited in conveying this knowledge base to serviceable equipment designers and are subject to misinterpretation. A mathematical model of task complexity based on measurable task parameters and telerobot performance characteristics would be a valuable tool to designers and operational planners. Oceaneering Space Systems and TRW have performed an independent research and development project to develop such a tool for telerobotic orbital replacement unit (ORU) exchange. This algorithm was developed to predict an ORU exchange degree of difficulty rating (based on the Cooper-Harper rating used to assess piloted operations). It is based on measurable parameters of the ORU, attachment receptacle and quantifiable telerobotic performance characteristics (e.g., link length, joint ranges, positional accuracy, tool lengths, number of cameras, and locations). The resulting algorithm can be used to predict task complexity as the ORU parameters, receptacle parameters, and telerobotic characteristics are varied.

  19. Estimating aquifer recharge in Mission River watershed, Texas: model development and calibration using genetic algorithms

    NASA Astrophysics Data System (ADS)

    Uddameri, V.; Kuchanur, M.

    2007-01-01

    Soil moisture balance studies provide a convenient approach to estimate aquifer recharge when only limited site-specific data are available. A monthly mass-balance approach has been utilized in this study to estimate recharge in a small watershed in the coastal bend of South Texas. The developed lumped parameter model employs four adjustable parameters to calibrate model predicted stream runoff to observations at a gaging station. A new procedure was developed to correctly capture the intermittent nature of rainfall. The total monthly rainfall was assigned to a single-equivalent storm whose duration was obtained via calibration. A total of four calibrations were carried out using an evolutionary computing technique called genetic algorithms as well as the conventional gradient descent (GD) technique. Ordinary least squares and the heteroscedastic maximum likelihood error (HMLE) based objective functions were evaluated as part of this study as well. While the genetic algorithm based calibrations were relatively better in capturing the peak runoff events, the GD based calibration did slightly better in capturing the low flow events. Treating the Box-Cox exponent in the HMLE function as a calibration parameter did not yield better estimates and the study corroborates the suggestion made in the literature of fixing this exponent at 0.3. The model outputs were compared against available information and results indicate that the developed modeling approach provides a conservative estimate of recharge.

  20. Development of ocean color algorithms for estimating chlorophyll-a concentrations and inherent optical properties using gene expression programming (GEP).

    PubMed

    Chang, Chih-Hua

    2015-03-01

    This paper proposes new inversion algorithms for the estimation of Chlorophyll-a concentration (Chla) and the ocean's inherent optical properties (IOPs) from the measurement of remote sensing reflectance (Rrs). With in situ data from the NASA bio-optical marine algorithm data set (NOMAD), inversion algorithms were developed by the novel gene expression programming (GEP) approach, which creates, manipulates and selects the most appropriate tree-structured functions based on evolutionary computing. The limitations and validity of the proposed algorithms are evaluated by simulated Rrs spectra with respect to NOMAD, and a closure test for IOPs obtained at a single reference wavelength. The application of GEP-derived algorithms is validated against in situ, synthetic and satellite match-up data sets compiled by NASA and the International Ocean Color Coordinate Group (IOCCG). The new algorithms are able to provide Chla and IOPs retrievals to those derived by other state-of-the-art regression approaches and obtained with the semi- and quasi-analytical algorithms, respectively. In practice, there are no significant differences between GEP, support vector regression, and multilayer perceptron model in terms of the overall performance. The GEP-derived algorithms are successfully applied in processing the images taken by the Sea Wide Field-of-view Sensor (SeaWiFS), generate Chla and IOPs maps which show better details of developing algal blooms, and give more information on the distribution of water constituents between different water bodies. PMID:25836776

  1. An algorithm for hyperspectral remote sensing of aerosols: 1. Development of theoretical framework

    NASA Astrophysics Data System (ADS)

    Hou, Weizhen; Wang, Jun; Xu, Xiaoguang; Reid, Jeffrey S.; Han, Dong

    2016-07-01

    This paper describes the first part of a series of investigations to develop algorithms for simultaneous retrieval of aerosol parameters and surface reflectance from a newly developed hyperspectral instrument, the GEOstationary Trace gas and Aerosol Sensor Optimization (GEO-TASO), by taking full advantage of available hyperspectral measurement information in the visible bands. We describe the theoretical framework of an inversion algorithm for the hyperspectral remote sensing of the aerosol optical properties, in which major principal components (PCs) for surface reflectance is assumed known, and the spectrally dependent aerosol refractive indices are assumed to follow a power-law approximation with four unknown parameters (two for real and two for imaginary part of refractive index). New capabilities for computing the Jacobians of four Stokes parameters of reflected solar radiation at the top of the atmosphere with respect to these unknown aerosol parameters and the weighting coefficients for each PC of surface reflectance are added into the UNified Linearized Vector Radiative Transfer Model (UNL-VRTM), which in turn facilitates the optimization in the inversion process. Theoretical derivations of the formulas for these new capabilities are provided, and the analytical solutions of Jacobians are validated against the finite-difference calculations with relative error less than 0.2%. Finally, self-consistency check of the inversion algorithm is conducted for the idealized green-vegetation and rangeland surfaces that were spectrally characterized by the U.S. Geological Survey digital spectral library. It shows that the first six PCs can yield the reconstruction of spectral surface reflectance with errors less than 1%. Assuming that aerosol properties can be accurately characterized, the inversion yields a retrieval of hyperspectral surface reflectance with an uncertainty of 2% (and root-mean-square error of less than 0.003), which suggests self-consistency in the

  2. Millimeter-wave Imaging Radiometer (MIR) data processing and development of water vapor retrieval algorithms

    NASA Technical Reports Server (NTRS)

    Chang, L. Aron

    1995-01-01

    This document describes the progress of the task of the Millimeter-wave Imaging Radiometer (MIR) data processing and the development of water vapor retrieval algorithms, for the second six-month performing period. Aircraft MIR data from two 1995 field experiments were collected and processed with a revised data processing software. Two revised versions of water vapor retrieval algorithm were developed, one for the execution of retrieval on a supercomputer platform, and one for using pressure as the vertical coordinate. Two implementations of incorporating products from other sensors into the water vapor retrieval system, one from the Special Sensor Microwave Imager (SSM/I), the other from the High-resolution Interferometer Sounder (HIS). Water vapor retrievals were performed for both airborne MIR data and spaceborne SSM/T-2 data, during field experiments of TOGA/COARE, CAMEX-1, and CAMEX-2. The climatology of water vapor during TOGA/COARE was examined by SSM/T-2 soundings and conventional rawinsonde.

  3. Developing algorithms for predicting protein-protein interactions of homology modeled proteins.

    SciTech Connect

    Martin, Shawn Bryan; Sale, Kenneth L.; Faulon, Jean-Loup Michel; Roe, Diana C.

    2006-01-01

    The goal of this project was to examine the protein-protein docking problem, especially as it relates to homology-based structures, identify the key bottlenecks in current software tools, and evaluate and prototype new algorithms that may be developed to improve these bottlenecks. This report describes the current challenges in the protein-protein docking problem: correctly predicting the binding site for the protein-protein interaction and correctly placing the sidechains. Two different and complementary approaches are taken that can help with the protein-protein docking problem. The first approach is to predict interaction sites prior to docking, and uses bioinformatics studies of protein-protein interactions to predict theses interaction site. The second approach is to improve validation of predicted complexes after docking, and uses an improved scoring function for evaluating proposed docked poses, incorporating a solvation term. This scoring function demonstrates significant improvement over current state-of-the art functions. Initial studies on both these approaches are promising, and argue for full development of these algorithms.

  4. Development of optimization model for sputtering process parameter based on gravitational search algorithm

    NASA Astrophysics Data System (ADS)

    Norlina, M. S.; Diyana, M. S. Nor; Mazidah, P.; Rusop, M.

    2016-07-01

    In the RF magnetron sputtering process, the desirable layer properties are largely influenced by the process parameters and conditions. If the quality of the thin film has not reached up to its intended level, the experiments have to be repeated until the desirable quality has been met. This research is proposing Gravitational Search Algorithm (GSA) as the optimization model to reduce the time and cost to be spent in the thin film fabrication. The optimization model's engine has been developed using Java. The model is developed based on GSA concept, which is inspired by the Newtonian laws of gravity and motion. In this research, the model is expected to optimize four deposition parameters which are RF power, deposition time, oxygen flow rate and substrate temperature. The results have turned out to be promising and it could be concluded that the performance of the model is satisfying in this parameter optimization problem. Future work could compare GSA with other nature based algorithms and test them with various set of data.

  5. Remote Sensing of Ocean Color in the Arctic: Algorithm Development and Comparative Validation. Chapter 9

    NASA Technical Reports Server (NTRS)

    Cota, Glenn F.

    2001-01-01

    The overall goal of this effort is to acquire a large bio-optical database, encompassing most environmental variability in the Arctic, to develop algorithms for phytoplankton biomass and production and other optically active constituents. A large suite of bio-optical and biogeochemical observations have been collected in a variety of high latitude ecosystems at different seasons. The Ocean Research Consortium of the Arctic (ORCA) is a collaborative effort between G.F. Cota of Old Dominion University (ODU), W.G. Harrison and T. Platt of the Bedford Institute of Oceanography (BIO), S. Sathyendranath of Dalhousie University and S. Saitoh of Hokkaido University. ORCA has now conducted 12 cruises and collected over 500 in-water optical profiles plus a variety of ancillary data. Observational suites typically include apparent optical properties (AOPs), inherent optical property (IOPs), and a variety of ancillary observations including sun photometry, biogeochemical profiles, and productivity measurements. All quality-assured data have been submitted to NASA's SeaWIFS Bio-Optical Archive and Storage System (SeaBASS) data archive. Our algorithm development efforts address most of the potential bio-optical data products for the Sea-Viewing Wide Field-of-view Sensor (SeaWiFS), Moderate Resolution Imaging Spectroradiometer (MODIS), and GLI, and provides validation for a specific areas of concern, i.e., high latitudes and coastal waters.

  6. Developing a Moving-Solid Algorithm for Simulating Tsunamis Induced by Rock Sliding

    NASA Astrophysics Data System (ADS)

    Chuang, M.; Wu, T.; Huang, C.; Wang, C.; Chu, C.; Chen, M.

    2012-12-01

    The landslide generated tsunami is one of the most devastating nature hazards. However, the involvement of the moving obstacle and dynamic free-surface movement makes the numerical simulation a difficult task. To describe the fluid motion, we use modified two-step projection method to decouple the velocity and pressure fields with 3D LES turbulent model. The free-surface movement is tracked by volume of fluid (VOF) method (Wu, 2004). To describe the effect from the moving obstacle on the fluid, a newly developed moving-solid algorithm (MSA) is developed. We combine the ideas from immersed boundary method (IBM) and partial-cell treatment (PCT) for specifying the contacting speed on the solid face and for presenting the obstacle blocking effect, respectively. By using the concept of IBM, the cell-center and cell-face velocities can be specified arbitrarily. And because we move the solid obstacle on a fixed grid, the boundary of the solid seldom coincides with the cell faces, which makes it inappropriate to assign the solid boundary velocity to the cell faces. To overcome this problem, the PCT is adopted. Using this algorithm, the solid surface is conceptually coincided with the cell faces, and the cell face velocity is able to be specified as the obstacle velocity. The advantage of using this algorithm is obtaining the stable pressure field which is extremely important for coupling with a force-balancing model which describes the solid motion. This model is therefore able to simulate incompressible high-speed fluid motion. In order to describe the solid motion, the DEM (Discrete Element Method) is adopted. The new-time solid movement can be predicted and divided into translation and rotation based on the Newton's equations and Euler's equations respectively. The detail of the moving-solid algorithm is presented in this paper. This model is then applied to studying the rock-slide generated tsunami. The results are validated with the laboratory data (Liu and Wu, 2005

  7. Development of Gis Tool for the Solution of Minimum Spanning Tree Problem using Prim's Algorithm

    NASA Astrophysics Data System (ADS)

    Dutta, S.; Patra, D.; Shankar, H.; Alok Verma, P.

    2014-11-01

    minimum spanning tree (MST) of a connected, undirected and weighted network is a tree of that network consisting of all its nodes and the sum of weights of all its edges is minimum among all such possible spanning trees of the same network. In this study, we have developed a new GIS tool using most commonly known rudimentary algorithm called Prim's algorithm to construct the minimum spanning tree of a connected, undirected and weighted road network. This algorithm is based on the weight (adjacency) matrix of a weighted network and helps to solve complex network MST problem easily, efficiently and effectively. The selection of the appropriate algorithm is very essential otherwise it will be very hard to get an optimal result. In case of Road Transportation Network, it is very essential to find the optimal results by considering all the necessary points based on cost factor (time or distance). This paper is based on solving the Minimum Spanning Tree (MST) problem of a road network by finding it's minimum span by considering all the important network junction point. GIS technology is usually used to solve the network related problems like the optimal path problem, travelling salesman problem, vehicle routing problems, location-allocation problems etc. Therefore, in this study we have developed a customized GIS tool using Python script in ArcGIS software for the solution of MST problem for a Road Transportation Network of Dehradun city by considering distance and time as the impedance (cost) factors. It has a number of advantages like the users do not need a greater knowledge of the subject as the tool is user-friendly and that allows to access information varied and adapted the needs of the users. This GIS tool for MST can be applied for a nationwide plan called Prime Minister Gram Sadak Yojana in India to provide optimal all weather road connectivity to unconnected villages (points). This tool is also useful for constructing highways or railways spanning several

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

    PubMed

    Xu, Lei; Jeavons, Peter

    2015-11-01

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

  9. Development and Implementation of a Hardware In-the-Loop Test Bed for Unmanned Aerial Vehicle Control Algorithms

    NASA Technical Reports Server (NTRS)

    Nyangweso, Emmanuel; Bole, Brian

    2014-01-01

    Successful prediction and management of battery life using prognostic algorithms through ground and flight tests is important for performance evaluation of electrical systems. This paper details the design of test beds suitable for replicating loading profiles that would be encountered in deployed electrical systems. The test bed data will be used to develop and validate prognostic algorithms for predicting battery discharge time and battery failure time. Online battery prognostic algorithms will enable health management strategies. The platform used for algorithm demonstration is the EDGE 540T electric unmanned aerial vehicle (UAV). The fully designed test beds developed and detailed in this paper can be used to conduct battery life tests by controlling current and recording voltage and temperature to develop a model that makes a prediction of end-of-charge and end-of-life of the system based on rapid state of health (SOH) assessment.

  10. Development of region processing algorithm for HSTAMIDS: status and field test results

    NASA Astrophysics Data System (ADS)

    Ngan, Peter; Burke, Sean; Cresci, Roger; Wilson, Joseph N.; Gader, Paul; Ho, K. C.; Bartosz, Elizabeth; Duvoisin, Herbert

    2007-04-01

    The Region Processing Algorithm (RPA) has been developed by the Office of the Army Humanitarian Demining Research and Development (HD R&D) Program as part of improvements for the AN/PSS-14. The effort was a collaboration between the HD R&D Program, L-3 Communication CyTerra Corporation, University of Florida, Duke University and University of Missouri. RPA has been integrated into and implemented in a real-time AN/PSS-14. The subject unit was used to collect data and tested for its performance at three Army test sites within the United States of America. This paper describes the status of the technology and its recent test results.

  11. Ocean observations with EOS/MODIS: Algorithm development and post launch studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1995-01-01

    Several significant accomplishments were made during the present reporting period. (1) Initial simulations to understand the applicability of the MODerate Resolution Imaging Spectrometer (MODIS) 1380 nm band for removing the effects of stratospheric aerosols and thin cirrus clouds were completed using a model for an aged volcanic aerosol. The results suggest that very simple procedures requiring no a priori knowledge of the optical properties of the stratospheric aerosol may be as effective as complex procedures requiring full knowledge of the aerosol properties, except the concentration which is estimated from the reflectance at 1380 nm. The limitations of this conclusion will be examined in the next reporting period; (2) The lookup tables employed in the implementation of the atmospheric correction algorithm have been modified in several ways intended to improve the accuracy and/or speed of processing. These have been delivered to R. Evans for implementation into the MODIS prototype processing algorithm for testing; (3) A method was developed for removal of the effects of the O2 'A' absorption band from SeaWiFS band 7 (745-785 nm). This is important in that SeaWiFS imagery will be used as a test data set for the MODIS atmospheric correction algorithm over the oceans; and (4) Construction of a radiometer, and associated deployment boom, for studying the spectral reflectance of oceanic whitecaps at sea was completed. The system was successfully tested on a cruise off Hawaii on which whitecaps were plentiful during October-November. This data set is now under analysis.

  12. The early life origin theory in the development of cardiovascular disease and type 2 diabetes.

    PubMed

    Lindblom, Runa; Ververis, Katherine; Tortorella, Stephanie M; Karagiannis, Tom C

    2015-04-01

    Life expectancy has been examined from a variety of perspectives in recent history. Epidemiology is one perspective which examines causes of morbidity and mortality at the population level. Over the past few 100 years there have been dramatic shifts in the major causes of death and expected life length. This change has suffered from inconsistency across time and space with vast inequalities observed between population groups. In current focus is the challenge of rising non-communicable diseases (NCD), such as cardiovascular disease and type 2 diabetes mellitus. In the search to discover methods to combat the rising incidence of these diseases, a number of new theories on the development of morbidity have arisen. A pertinent example is the hypothesis published by David Barker in 1995 which postulates the prenatal and early developmental origin of adult onset disease, and highlights the importance of the maternal environment. This theory has been subject to criticism however it has gradually gained acceptance. In addition, the relatively new field of epigenetics is contributing evidence in support of the theory. This review aims to explore the implication and limitations of the developmental origin hypothesis, via an historical perspective, in order to enhance understanding of the increasing incidence of NCDs, and facilitate an improvement in planning public health policy.

  13. [A Research on the origin and development of standardization of Chinese medical case records].

    PubMed

    Zhang, Lei

    2014-11-01

    The origin of Chinese medical case history is rather early. Chunyu Yi's medical cases (zhen ji) of the Western Han Dynasty were the earliest actual extant medical case with the practical contents. In the Ming Dynasty, Han Mao put forward firstly the principles of "six aspects must be recorded" for writing the pulse record, as the beginning of the standardization of medical case record. Later, Wu Kun, Yu Yan, Li Yanzhen, He Lianchen et al. supplemented, adjusted and changed the format of medical case record. After 1949, the format of medical case record was revised several times to form the national standard. In fact, the clinical medical case record is different from the case history. The modern medical case record could not reflect fully the thinking process of traditional Chinese medicine (TCM) and the essence of the treatment based on syndrome differentiation. Exploring the origin and development of the standardization of medical case record will benefit for the improvement of modern format of medical case record. PMID:25620355

  14. Historical perspective: The problem of the origin of life in the context of developments in biology

    NASA Astrophysics Data System (ADS)

    Kamminga, Harmke

    1988-03-01

    The structure of the history of scientific ideas on the origin of life, after Darwin's theory of evolution brought the problem into focus, is discussed. 19th-century theories in the mainstream of historical development already included some notion of chemical evolution. These theories were limited, however, by their reliance on a protoplasmic view of life, according to which the protoplasmic substance combines all vital properties. It was only when this holistic concept of protoplasm was abandoned that a clear distinction between different vital functions such as metabolism and replication was made. This led to two schools of thought in the origin of life field, one inspired by biochemistry and one by genetics. Oparin's theory, which was rooted in the metabolic traditions of biochemistry, provided a model which has had a lasting impact in methodological terms and which helped to transform the field from a largely theoretical one to an area of active research. Genetically based theories, on the other hand, had a delayed impact in this respect, because of long-lasting uncertainty regarding the structural basis of gene function.

  15. Development of a highly immunogenic Newcastle disease virus chicken vaccine strain of duck origin.

    PubMed

    Kim, J Y; Kye, S J; Lee, H J; Gaikwad, S; Lee, H S; Jung, S C; Choi, K S

    2016-04-01

    Newcastle disease virus (NDV) strain NDRL0901 was developed as a live vaccine candidate for control of Newcastle disease. NDV isolate KR/duck/13/07 (DK1307) of duck origin was used as the selected vaccine strain. DK1307 was passaged 6 times in chickens. Then a single clone from the chicken-adapted virus (DK1307C) was finally selected, and the vaccine strain was named NDRL0901. DK1307C and the clone NDRL0901 viruses showed enhanced immunogenicity compared to the DK1307 virus. Principal component analysis based on fusion and hemagglutinin-neuraminidase genes revealed the codon usage pattern in the dataset is distinct separating duck viral sequences and avian sequences, and passage of the duck origin virus into the chicken host causes deviation in the codon usage pattern. The NDRL0901 virus was avirulent and did not acquire viral virulence even after 7 back passages in chickens. When day-old chicks were vaccinated with the NDRL0901 virus via spray, eye drops, and drinking water, the vaccinated birds showed no clinical signs and had significant protection efficacy (>80%) against very virulent NDV (Kr005 strain) infection regardless of the administration route employed. The results indicate that the NDRL0901 strain is safe in chickens and can offer protective immunity.

  16. The settling dynamics of flocculating mud-sand mixtures: Part 1—Empirical algorithm development

    NASA Astrophysics Data System (ADS)

    Manning, Andrew James; Baugh, John V.; Spearman, Jeremy R.; Pidduck, Emma L.; Whitehouse, Richard J. S.

    2011-03-01

    , and in most cases produced excessive over-estimations in MSF. The reason for these predictive errors was that this hybrid approach still treated mud and sand separately. This is potentially reasonable if the sediments are segregated and non-interactive, but appears to be unacceptable when the mud and sand are flocculating via an interactive matrix. The MSSV empirical model may be regarded as a `first stage' approximation for scientists and engineers either wishing to investigate mixed-sediment flocculation and its depositional characteristics in a quantifiable framework, or simulate mixed-sediment settling in a numerical sediment transport model where flocculation is occurring. The preliminary assessment concluded that in general when all the SPM and shear stress range data were combined, the net result indicated that the new mixed-sediment settling velocity empirical model was only in error by -3 to -6.7% across the experimental mud:sand mixture ratios. Tuning of the algorithm coefficients is required for the accurate prediction of depositional rates in a specific estuary, as was demonstrated by the algorithm calibration using data from Portsmouth Harbour. The development of a more physics-based model, which captures the essential features of the empirical MSSV model, would be more universally applicable.

  17. A Prototype Hail Detection Algorithm and Hail Climatology Developed with the Advanced Microwave Sounding Unit (AMSU)

    NASA Technical Reports Server (NTRS)

    Ferraro, Ralph; Beauchamp, James; Cecil, Dan; Heymsfeld, Gerald

    2015-01-01

    In previous studies published in the open literature, a strong relationship between the occurrence of hail and the microwave brightness temperatures (primarily at 37 and 85 GHz) was documented. These studies were performed with the Nimbus-7 SMMR, the TRMM Microwave Imager (TMI) and most recently, the Aqua AMSR-E sensor. This lead to climatologies of hail frequency from TMI and AMSR-E, however, limitations include geographical domain of the TMI sensor (35 S to 35 N) and the overpass time of the Aqua satellite (130 am/pm local time), both of which reduce an accurate mapping of hail events over the global domain and the full diurnal cycle. Nonetheless, these studies presented exciting, new applications for passive microwave sensors. Since 1998, NOAA and EUMETSAT have been operating the AMSU-A/B and the MHS on several operational satellites: NOAA-15 through NOAA-19; MetOp-A and -B. With multiple satellites in operation since 2000, the AMSU/MHS sensors provide near global coverage every 4 hours, thus, offering a much larger time and temporal sampling than TRMM or AMSR-E. With similar observation frequencies near 30 and 85 GHz and additionally three at the 183 GHz water vapor band, the potential to detect strong convection associated with severe storms on a more comprehensive time and space scale exists. In this study, we develop a prototype AMSU-based hail detection algorithm through the use of collocated satellite and surface hail reports over the continental U.S. for a 12-year period (2000-2011). Compared with the surface observations, the algorithm detects approximately 40 percent of hail occurrences. The simple threshold algorithm is then used to generate a hail climatology that is based on all available AMSU observations during 2000-11 that is stratified in several ways, including total hail occurrence by month (March through September), total annual, and over the diurnal cycle. Independent comparisons are made compared to similar data sets derived from other

  18. Microphysical particle properties derived from inversion algorithms developed in the framework of EARLINET

    NASA Astrophysics Data System (ADS)

    Müller, D.; Böckmann, C.; Kolgotin, A.; Schneidenbach, L.; Chemyakin, E.; Rosemann, J.; Znak, P.; Romanov, A.

    2015-12-01

    We present a summary on the current status of two inversion algorithms that are used in EARLINET for the inversion of data collected with EARLINET multiwavelength Raman lidars. These instruments measure backscatter coefficients at 355, 532, and 1064 nm, and extinction coefficients at 355 and 532 nm. Development of these two algorithms started in 2000 when EARLINET was founded. The algorithms are based on manually controlled inversion of optical data which allows for detailed sensitivity studies and thus provides us with comparably high quality of the derived data products. The algorithms allow us to derive particle effective radius, and volume and surface-area concentration with comparably high confidence. The retrieval of the real and imaginary parts of the complex refractive index still is a challenge in view of the accuracy required for these parameters in climate change studies in which light-absorption needs to be known with high accuracy. Single-scattering albedo can be computed from the retrieved microphysical parameters and allows us to categorize aerosols into high and low absorbing aerosols. We discuss the current status of these manually operated algorithms, the potentially achievable accuracy of data products, and the goals for future work on the basis of a few exemplary simulations with synthetic optical data. The optical data used in our study cover a range of Ångström exponents and extinction-to-backscatter (lidar) ratios that are found from lidar measurements of various aerosol types. We also tested aerosol scenarios that are considered highly unlikely, e.g., the lidar ratios fall outside the commonly accepted range of values measured with Raman lidar, even though the underlying microphysical particle properties are not uncommon. The goal of this part of the study is to test robustness of the algorithms toward their ability to identify aerosol types that have not been measured so far, but cannot be ruled out based on our current knowledge of

  19. Description of ALARMA: the alarm algorithm developed for the Nuclear Car Wash

    SciTech Connect

    Luu, T; Biltoft, P; Church, J; Descalle, M; Hall, J; Manatt, D; Mauger, J; Norman, E; Petersen, D; Pruet, J; Prussin, S; Slaughter, D

    2006-11-28

    The goal of any alarm algorithm should be that it provide the necessary tools to derive confidence limits on whether the existence of fissile materials is present in cargo containers. It should be able to extract these limits from (usually) noisy and/or weak data while maintaining a false alarm rate (FAR) that is economically suitable for port operations. It should also be able to perform its analysis within a reasonably short amount of time (i.e. {approx} seconds). To achieve this, it is essential that the algorithm be able to identify and subtract any interference signature that might otherwise be confused with a fissile signature. Lastly, the algorithm itself should be user-intuitive and user-friendly so that port operators with little or no experience with detection algorithms may use it with relative ease. In support of the Nuclear Car Wash project at Lawrence Livermore Laboratory, we have developed an alarm algorithm that satisfies the above requirements. The description of the this alarm algorithm, dubbed ALARMA, is the purpose of this technical report. The experimental setup of the nuclear car wash has been well documented [1, 2, 3]. The presence of fissile materials is inferred by examining the {beta}-delayed gamma spectrum induced after a brief neutron irradiation of cargo, particularly in the high-energy region above approximately 2.5 MeV. In this region naturally occurring gamma rays are virtually non-existent. Thermal-neutron induced fission of {sup 235}U and {sup 239}P, on the other hand, leaves a unique {beta}-delayed spectrum [4]. This spectrum comes from decays of fission products having half-lives as large as 30 seconds, many of which have high Q-values. Since high-energy photons penetrate matter more freely, it is natural to look for unique fissile signatures in this energy region after neutron irradiation. The goal of this interrogation procedure is a 95% success rate of detection of as little as 5 kilograms of fissile material while retaining

  20. White Light Modeling, Algorithm Development, and Validation on the Micro-arcsecond Metrology Testbed

    NASA Technical Reports Server (NTRS)

    Milman, Mark H.; Regher, Martin; Shen, Tsae Pyng

    2004-01-01

    The Space Interferometry Mission (SIM) scheduled for launch in early 2010, is an optical interferometer that will perform narrow angle and global wide angle astrometry with unprecedented accuracy, providing differential position accuracies of 1uas, and 4uas global accuracies in position, proper motion and parallax. The astrometric observations of the SIM instrument are performed via delay measurements provided by three Michelson-type, white light interferometers. Two 'guide' interferometers acquire fringes on bright guide stars in order to make highly precise measurements of variations in spacecraft attitude, while the third interferometer performs the science measurement. SIM derives its performance from a combination of precise fringe measurements of the interfered starlight (a few ten-thousandths of a wave) and very precise (tens of picometers) relative distance measurements made between a set of fiducials. The focus of the present paper is on the development and analysis of algorithms for accurate white light estimation, and on validating some of these algorithms on the MicroArcsecond Testbed.

  1. Path optimization by a variational reaction coordinate method. I. Development of formalism and algorithms

    SciTech Connect

    Birkholz, Adam B.; Schlegel, H. Bernhard

    2015-12-28

    The development of algorithms to optimize reaction pathways between reactants and products is an active area of study. Existing algorithms typically describe the path as a discrete series of images (chain of states) which are moved downhill toward the path, using various reparameterization schemes, constraints, or fictitious forces to maintain a uniform description of the reaction path. The Variational Reaction Coordinate (VRC) method is a novel approach that finds the reaction path by minimizing the variational reaction energy (VRE) of Quapp and Bofill. The VRE is the line integral of the gradient norm along a path between reactants and products and minimization of VRE has been shown to yield the steepest descent reaction path. In the VRC method, we represent the reaction path by a linear expansion in a set of continuous basis functions and find the optimized path by minimizing the VRE with respect to the linear expansion coefficients. Improved convergence is obtained by applying constraints to the spacing of the basis functions and coupling the minimization of the VRE to the minimization of one or more points along the path that correspond to intermediates and transition states. The VRC method is demonstrated by optimizing the reaction path for the Müller-Brown surface and by finding a reaction path passing through 5 transition states and 4 intermediates for a 10 atom Lennard-Jones cluster.

  2. Path optimization by a variational reaction coordinate method. I. Development of formalism and algorithms.

    PubMed

    Birkholz, Adam B; Schlegel, H Bernhard

    2015-12-28

    The development of algorithms to optimize reaction pathways between reactants and products is an active area of study. Existing algorithms typically describe the path as a discrete series of images (chain of states) which are moved downhill toward the path, using various reparameterization schemes, constraints, or fictitious forces to maintain a uniform description of the reaction path. The Variational Reaction Coordinate (VRC) method is a novel approach that finds the reaction path by minimizing the variational reaction energy (VRE) of Quapp and Bofill. The VRE is the line integral of the gradient norm along a path between reactants and products and minimization of VRE has been shown to yield the steepest descent reaction path. In the VRC method, we represent the reaction path by a linear expansion in a set of continuous basis functions and find the optimized path by minimizing the VRE with respect to the linear expansion coefficients. Improved convergence is obtained by applying constraints to the spacing of the basis functions and coupling the minimization of the VRE to the minimization of one or more points along the path that correspond to intermediates and transition states. The VRC method is demonstrated by optimizing the reaction path for the Müller-Brown surface and by finding a reaction path passing through 5 transition states and 4 intermediates for a 10 atom Lennard-Jones cluster.

  3. Development of an algorithm for production of inactivated arbovirus antigens in cell culture

    PubMed Central

    Goodman, C.H.; Russell, B.J.; Velez, J.O.; Laven, J.J.; Nicholson, W.L; Bagarozzi, D.A.; Moon, J.L.; Bedi, K.; Johnson, B.W.

    2015-01-01

    Arboviruses are medically important pathogens that cause human disease ranging from a mild fever to encephalitis. Laboratory diagnosis is essential to differentiate arbovirus infections from other pathogens with similar clinical manifestations. The Arboviral Diseases Branch (ADB) reference laboratory at the CDC Division of Vector-Borne Diseases (DVBD) produces reference antigens used in serological assays such as the virus-specific immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Antigen production in cell culture has largely replaced the use of suckling mice; however, the methods are not directly transferable. The development of a cell culture antigen production algorithm for nine arboviruses from the three main arbovirus families, Flaviviridae, Togaviridae, and Bunyaviridae, is described here. Virus cell culture growth and harvest conditions were optimized, inactivation methods were evaluated, and concentration procedures were compared for each virus. Antigen performance was evaluated by the MAC-ELISA at each step of the procedure. The antigen production algorithm is a framework for standardization of methodology and quality control; however, a single antigen production protocol was not applicable to all arboviruses and needed to be optimized for each virus. PMID:25102428

  4. Development of an algorithm for production of inactivated arbovirus antigens in cell culture.

    PubMed

    Goodman, C H; Russell, B J; Velez, J O; Laven, J J; Nicholson, W L; Bagarozzi, D A; Moon, J L; Bedi, K; Johnson, B W

    2014-11-01

    Arboviruses are medically important pathogens that cause human disease ranging from a mild fever to encephalitis. Laboratory diagnosis is essential to differentiate arbovirus infections from other pathogens with similar clinical manifestations. The Arboviral Diseases Branch (ADB) reference laboratory at the CDC Division of Vector-Borne Diseases (DVBD) produces reference antigens used in serological assays such as the virus-specific immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Antigen production in cell culture has largely replaced the use of suckling mice; however, the methods are not directly transferable. The development of a cell culture antigen production algorithm for nine arboviruses from the three main arbovirus families, Flaviviridae, Togaviridae, and Bunyaviridae, is described here. Virus cell culture growth and harvest conditions were optimized, inactivation methods were evaluated, and concentration procedures were compared for each virus. Antigen performance was evaluated by the MAC-ELISA at each step of the procedure. The antigen production algorithm is a framework for standardization of methodology and quality control; however, a single antigen production protocol was not applicable to all arboviruses and needed to be optimized for each virus.

  5. Development of an algorithm for production of inactivated arbovirus antigens in cell culture.

    PubMed

    Goodman, C H; Russell, B J; Velez, J O; Laven, J J; Nicholson, W L; Bagarozzi, D A; Moon, J L; Bedi, K; Johnson, B W

    2014-11-01

    Arboviruses are medically important pathogens that cause human disease ranging from a mild fever to encephalitis. Laboratory diagnosis is essential to differentiate arbovirus infections from other pathogens with similar clinical manifestations. The Arboviral Diseases Branch (ADB) reference laboratory at the CDC Division of Vector-Borne Diseases (DVBD) produces reference antigens used in serological assays such as the virus-specific immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Antigen production in cell culture has largely replaced the use of suckling mice; however, the methods are not directly transferable. The development of a cell culture antigen production algorithm for nine arboviruses from the three main arbovirus families, Flaviviridae, Togaviridae, and Bunyaviridae, is described here. Virus cell culture growth and harvest conditions were optimized, inactivation methods were evaluated, and concentration procedures were compared for each virus. Antigen performance was evaluated by the MAC-ELISA at each step of the procedure. The antigen production algorithm is a framework for standardization of methodology and quality control; however, a single antigen production protocol was not applicable to all arboviruses and needed to be optimized for each virus. PMID:25102428

  6. Development of TIF based figuring algorithm for deterministic pitch tool polishing

    NASA Astrophysics Data System (ADS)

    Yi, Hyun-Su; Kim, Sug-Whan; Yang, Ho-Soon; Lee, Yun-Woo

    2007-12-01

    Pitch is perhaps the oldest material used for optical polishing, leaving superior surface texture, and has been used widely in the optics shop floor. However, for its unpredictable controllability of removal characteristics, the pitch tool polishing has been rarely analysed quantitatively and many optics shops rely heavily on optician's "feel" even today. In order to bring a degree of process controllability to the pitch tool polishing, we added motorized tool motions to the conventional Draper type polishing machine and modelled the tool path in the absolute machine coordinate. We then produced a number of Tool Influence Function (TIF) both from an analytical model and a series of experimental polishing runs using the pitch tool. The theoretical TIFs agreed well with the experimental TIFs to the profile accuracy of 79 % in terms of its shape. The surface figuring algorithm was then developed in-house utilizing both theoretical and experimental TIFs. We are currently undertaking a series of trial figuring experiments to prove the performance of the polishing algorithm, and the early results indicate that the highly deterministic material removal control with the pitch tool can be achieved to a certain level of form error. The machine renovation, TIF theory and experimental confirmation, figuring simulation results are reported together with implications to deterministic polishing.

  7. Path optimization by a variational reaction coordinate method. I. Development of formalism and algorithms

    NASA Astrophysics Data System (ADS)

    Birkholz, Adam B.; Schlegel, H. Bernhard

    2015-12-01

    The development of algorithms to optimize reaction pathways between reactants and products is an active area of study. Existing algorithms typically describe the path as a discrete series of images (chain of states) which are moved downhill toward the path, using various reparameterization schemes, constraints, or fictitious forces to maintain a uniform description of the reaction path. The Variational Reaction Coordinate (VRC) method is a novel approach that finds the reaction path by minimizing the variational reaction energy (VRE) of Quapp and Bofill. The VRE is the line integral of the gradient norm along a path between reactants and products and minimization of VRE has been shown to yield the steepest descent reaction path. In the VRC method, we represent the reaction path by a linear expansion in a set of continuous basis functions and find the optimized path by minimizing the VRE with respect to the linear expansion coefficients. Improved convergence is obtained by applying constraints to the spacing of the basis functions and coupling the minimization of the VRE to the minimization of one or more points along the path that correspond to intermediates and transition states. The VRC method is demonstrated by optimizing the reaction path for the Müller-Brown surface and by finding a reaction path passing through 5 transition states and 4 intermediates for a 10 atom Lennard-Jones cluster.

  8. Development of a pharmacogenetic-guided warfarin dosing algorithm for Puerto Rican patients

    PubMed Central

    Ramos, Alga S; Seip, Richard L; Rivera-Miranda, Giselle; Felici-Giovanini, Marcos E; Garcia-Berdecia, Rafael; Alejandro-Cowan, Yirelia; Kocherla, Mohan; Cruz, Iadelisse; Feliu, Juan F; Cadilla, Carmen L; Renta, Jessica Y; Gorowski, Krystyna; Vergara, Cunegundo; Ruaño, Gualberto; Duconge, Jorge

    2012-01-01

    Aim This study was aimed at developing a pharmacogenetic-driven warfarin-dosing algorithm in 163 admixed Puerto Rican patients on stable warfarin therapy. Patients & methods A multiple linear-regression analysis was performed using log-transformed effective warfarin dose as the dependent variable, and combining CYP2C9 and VKORC1 genotyping with other relevant nongenetic clinical and demographic factors as independent predictors. Results The model explained more than two-thirds of the observed variance in the warfarin dose among Puerto Ricans, and also produced significantly better ‘ideal dose’ estimates than two pharmacogenetic models and clinical algorithms published previously, with the greatest benefit seen in patients ultimately requiring <7 mg/day. We also assessed the clinical validity of the model using an independent validation cohort of 55 Puerto Rican patients from Hartford, CT, USA (R2 = 51%). Conclusion Our findings provide the basis for planning prospective pharmacogenetic studies to demonstrate the clinical utility of genotyping warfarin-treated Puerto Rican patients. PMID:23215886

  9. How the challenge of explaining learning influenced the origins and development of John B. Watson's behaviorism.

    PubMed

    Rilling, M

    2000-01-01

    Before he invented behaviorism, John B. Watson considered learning one of the most important topics in psychology. Watson conducted excellent empirical research on animal learning. He developed behaviorism in part to promote research and elevate the status of learning in psychology. Watson was much less successful in the adequacy and originality of the mechanisms he proposed to explain learning. By assimilating the method of classical conditioning and adopting Pavlov's theory of stimulus substitution, Watson linked behaviorism with a new method that could compete with both Titchener's method of introspection and Freud's methods of psychoanalysis. Watson's interest in explaining psychopathology led to the discovery of conditioned emotional responses and a behavioristic explanation for the learning of phobic behavior. Watson established learning as a central topic for basic research and application in American psychology.

  10. New Insights Into Tissue Macrophages: From Their Origin to the Development of Memory.

    PubMed

    Italiani, Paola; Boraschi, Diana

    2015-08-01

    Macrophages are the main effector cells of innate immunity and are involved in inflammatory and anti-infective processes. They also have an essential role in maintaining tissue homeostasis, supporting tissue development, and repairing tissue damage. Until few years ago, it was believed that tissue macrophages derived from circulating blood monocytes, which terminally differentiated in the tissue and unable to proliferate. Recent evidence in the biology of tissue macrophages has uncovered a series of immune and ontogenic features that had been neglected for long, despite old observations. These include origin, heterogeneity, proliferative potential (or self-renewal), polarization, and memory. In recent years, the number of publications on tissue resident macrophages has grown rapidly, highlighting the renewed interest of the immunologists for these key players of innate immunity. This mini-review aims to summarizing the new current knowledge in macrophage immunobiology, in order to offer a clear and immediate overview of the field.

  11. Novel origins of lineage founder cells in the direct-developing sea urchin Heliocidaris erythrogramma.

    PubMed

    Wray, G A; Raff, R A

    1990-09-01

    The lineage and fate of each blastomere in the 32-cell embryo of the direct-developing sea urchin Heliocidaris erythrogramma have been traced by microinjection of tetramethylrhodamine-dextran. The results reveal substantive evolutionary modifications of the ancestral cell lineage pattern of indirect sea urchin development. Significant among these modifications are changes in the time and order of cell lineage segregation: vegetal ectodermal founder cells consistently arise earlier than during indirect development, while internal founder cells generally segregate later and in a different sequence. Modifications have also arisen in proportions of the embryo fated to become various cell types and larval structures. Ectodermal fates, particularly vestibular ectoderm, comprise a greater proportion of the total cellular volume in H. erythrogramma. Among internal cell types, coelom consumes more and endoderm less of the remaining cellular volume than during indirect sea urchin development. Evolutionary modifications are also apparent in the positional origin of larval cell types and structures in H. erythrogramma. These include an apparent tilt in the axis of prospective cell fate relative to the animal-vegetal axis as defined by cleavage planes. Together these evolutionary changes in the cell lineage of H. erythrogramma produce an accelerated loss of dorsoventral symmetry in cell fate relative to indirect development. The extent and diversity of rearrangements in its cell lineage indicate that the non-feeding larva of H. erythrogramma is a highly modified, novel form rather than a degenerate pluteus larva. These same modifications underscore the evolutionarily flexible relationship between cell lineage, gene expression, and larval morphology in sea urchin development.

  12. The fetal origins of memory: the role of dietary choline in optimal brain development.

    PubMed

    Zeisel, Steven H

    2006-11-01

    Fetal nutrition sets the stage for organ function in later life. In this review we discuss the fetal and neonatal origins of brain function. Numerous research observations point to the importance of choline for the developing fetus and neonate. This essential nutrient is involved in 1-carbon metabolism and is the precursor for many important compounds, including phospholipids, acetylcholine, and the methyl donor betaine. Dietary intake of choline by the pregnant mother and later by the infant directly affects brain development and results in permanent changes in brain function. In rodents, perinatal supplementation of choline enhances memory and learning functions, changes that endure across the lifespan. Conversely, choline deficiency during these sensitive periods results in memory and cognitive deficits that also persist. Furthermore, recent studies suggest that perinatal choline supplementation can reduce the behavioral effects of prenatal stress and the cognitive effects of prenatal alcohol exposure in offspring. The likely mechanism for these effects of choline involves DNA methylation, altered gene expression, and associated changes in stem cell proliferation and differentiation. The currently available animal data on choline and hippocampal development are compelling, but studies are needed to determine whether the same is true in humans. PMID:17212955

  13. NASA's Physics of the Cosmos and Cosmic Origins Technology Development Programs

    NASA Technical Reports Server (NTRS)

    Clampin, Mark; Pham, Thai

    2014-01-01

    NASA's Physics of the Cosmos (PCOS) and Cosmic Origins (COR) Program Offices, established in 2011, reside at the NASA Goddard Space Flight Center (GSFC). The offices serve as the implementation arm for the Astrophysics Division at NASA Headquarters. We present an overview of the programs' technology development activities and technology investment portfolio, funded by NASA's Strategic Astrophysics Technology (SAT) program. We currently fund 19 technology advancements to enable future PCOS and COR missions to help answer the questions "How did our universe begin and evolve?" and "How did galaxies, stars, and planets come to be?" We discuss the process for addressing community-provided technology gaps and Technology Management Board (TMB)-vetted prioritization and investment recommendations that inform the SAT program. The process improves the transparency and relevance of our technology investments, provides the community a voice in the process, and promotes targeted external technology investments by defining needs and identifying customers. The programs' goal is to promote and support technology development needed to enable missions envisioned by the National Research Council's (NRC) "New Worlds, New Horizons in Astronomy and Astrophysics" (NWNH) Decadal Survey report [1] and the Astrophysics Implementation Plan (AIP) [2]. These include technology development for dark energy, gravitational waves, X-ray and inflation probe science, and a 4m-class UV/optical telescope to conduct imaging and spectroscopy studies, as a post-Hubble observatory with significantly improved sensitivity and capability.

  14. NASA's Physics of the Cosmos and Cosmic Origins technology development programs

    NASA Astrophysics Data System (ADS)

    Clampin, Mark; Pham, Thai

    2014-07-01

    NASA's Physics of the Cosmos (PCOS) and Cosmic Origins (COR) Program Offices, established in 2011, reside at the NASA Goddard Space Flight Center (GSFC). The offices serve as the implementation arm for the Astrophysics Division at NASA Headquarters. We present an overview of the programs' technology development activities and technology investment portfolio, funded by NASA's Strategic Astrophysics Technology (SAT) program. We currently fund 19 technology advancements to enable future PCOS and COR missions to help answer the questions "How did our universe begin and evolve?" and "How did galaxies, stars, and planets come to be?" We discuss the process for addressing community-provided technology gaps and Technology Management Board (TMB)-vetted prioritization and investment recommendations that inform the SAT program. The process improves the transparency and relevance of our technology investments, provides the community a voice in the process, and promotes targeted external technology investments by defining needs and identifying customers. The programs' goal is to promote and support technology development needed to enable missions envisioned by the National Research Council's (NRC) "New Worlds, New Horizons in Astronomy and Astrophysics" (NWNH) Decadal Survey report [1] and the Astrophysics Implementation Plan (AIP) [2]. These include technology development for dark energy, gravitational waves, X-ray and inflation probe science, and a 4m-class UV/optical telescope to conduct imaging and spectroscopy studies, as a post-Hubble observatory with significantly improved sensitivity and capability.

  15. Japanese printing has been multi-media since its origin! : Rediscovering that development of printing culture is the origin of information society from a talk of Kochi Kabayama, Director, Printing Museum, Tokyo.

    NASA Astrophysics Data System (ADS)

    Morita, Utako

    Japanese printing has been multi-media since its origin! : Rediscovering that development of printing culture is the origin of information society from a talk of Kochi Kabayama, Director, Printing Museum, Tokyo.

  16. Developing Image Processing Meta-Algorithms with Data Mining of Multiple Metrics

    PubMed Central

    Cunha, Alexandre; Toga, A. W.; Parker, D. Stott

    2014-01-01

    People often use multiple metrics in image processing, but here we take a novel approach of mining the values of batteries of metrics on image processing results. We present a case for extending image processing methods to incorporate automated mining of multiple image metric values. Here by a metric we mean any image similarity or distance measure, and in this paper we consider intensity-based and statistical image measures and focus on registration as an image processing problem. We show how it is possible to develop meta-algorithms that evaluate different image processing results with a number of different metrics and mine the results in an automated fashion so as to select the best results. We show that the mining of multiple metrics offers a variety of potential benefits for many image processing problems, including improved robustness and validation. PMID:24653748

  17. Development of a Collins-type cryocooler floating piston control algorithm

    NASA Astrophysics Data System (ADS)

    Hogan, Jake; Hannon, Charles L.; Brisson, John

    2012-06-01

    The Collins-type cryocooler uses a floating piston design for the working fluid expansion. The piston floats between a cold volume, where the working fluid is expanded, and a warm volume. The piston is shuttled between opposite ends of the closed cylinder by opening and closing valves connecting several reservoirs at various pressures to the warm volume. Ideally, these pressures should be distributed between the high and low system pressure to gain good control of the piston motion. In this work, a numerical quasi-steady thermodynamic model is developed for the piston cycle. The model determines the steady state pressure distribution of the reservoirs for a given control algorithm. The results are then extended to show how valve timing modifications can be used to overcome helium leakage past the piston during operation.

  18. Development of a Low-Lift Chiller Controller and Simplified Precooling Control Algorithm - Final Report

    SciTech Connect

    Gayeski, N.; Armstrong, Peter; Alvira, M.; Gagne, J.; Katipamula, Srinivas

    2011-11-30

    KGS Buildings LLC (KGS) and Pacific Northwest National Laboratory (PNNL) have developed a simplified control algorithm and prototype low-lift chiller controller suitable for model-predictive control in a demonstration project of low-lift cooling. Low-lift cooling is a highly efficient cooling strategy conceived to enable low or net-zero energy buildings. A low-lift cooling system consists of a high efficiency low-lift chiller, radiant cooling, thermal storage, and model-predictive control to pre-cool thermal storage overnight on an optimal cooling rate trajectory. We call the properly integrated and controlled combination of these elements a low-lift cooling system (LLCS). This document is the final report for that project.

  19. Development of Web-Based Menu Planning Support System and its Solution Using Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Kashima, Tomoko; Matsumoto, Shimpei; Ishii, Hiroaki

    2009-10-01

    Recently lifestyle-related diseases have become an object of public concern, while at the same time people are being more health conscious. As an essential factor for causing the lifestyle-related diseases, we assume that the knowledge circulation on dietary habits is still insufficient. This paper focuses on everyday meals close to our life and proposes a well-balanced menu planning system as a preventive measure of lifestyle-related diseases. The system is developed by using a Web-based frontend and it provides multi-user services and menu information sharing capabilities like social networking services (SNS). The system is implemented on a Web server running Apache (HTTP server software), MySQL (database management system), and PHP (scripting language for dynamic Web pages). For the menu planning, a genetic algorithm is applied by understanding this problem as multidimensional 0-1 integer programming.

  20. Develop algorithms to improve detectability of defects in Sonic IR imaging NDE

    NASA Astrophysics Data System (ADS)

    Obeidat, Omar; Yu, Qiuye; Han, Xiaoyan

    2016-02-01

    Sonic Infrared (IR) technology is relative new in the NDE family. It is a fast, wide area imaging method. It combines ultrasound excitation and infrared imaging while the former to apply ultrasound energy thus induce friction heating in defects and the latter to capture the IR emission from the target. This technology can detect both surface and subsurface defects such as cracks and disbands/delaminations in various materials, metal/metal alloy or composites. However, certain defects may results in only very small IR signature be buried in noise or heating patterns. In such cases, to effectively extract the defect signals becomes critical in identifying the defects. In this paper, we will present algorithms which are developed to improve the detectability of defects in Sonic IR.

  1. Algorithm and code development for unsteady three-dimensional Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Obayashi, Shigeru

    1993-01-01

    In the last two decades, there have been extensive developments in computational aerodynamics, which constitutes a major part of the general area of computational fluid dynamics. Such developments are essential to advance the understanding of the physics of complex flows, to complement expensive wind-tunnel tests, and to reduce the overall design cost of an aircraft, particularly in the area of aeroelasticity. Aeroelasticity plays an important role in the design and development of aircraft, particularly modern aircraft, which tend to be more flexible. Several phenomena that can be dangerous and limit the performance of an aircraft occur because of the interaction of the flow with flexible components. For example, an aircraft with highly swept wings may experience vortex-induced aeroelastic oscillations. Also, undesirable aeroelastic phenomena due to the presence and movement of shock waves occur in the transonic range. Aeroelastically critical phenomena, such as a low transonic flutter speed, have been known to occur through limited wind-tunnel tests and flight tests. Aeroelastic tests require extensive cost and risk. An aeroelastic wind-tunnel experiment is an order of magnitude more expensive than a parallel experiment involving only aerodynamics. By complementing the wind-tunnel experiments with numerical simulations the overall cost of the development of aircraft can be considerably reduced. In order to accurately compute aeroelastic phenomenon it is necessary to solve the unsteady Euler/Navier-Stokes equations simultaneously with the structural equations of motion. These equations accurately describe the flow phenomena for aeroelastic applications. At Ames a code, ENSAERO, is being developed for computing the unsteady aerodynamics and aeroelasticity of aircraft and it solves the Euler/Navier-Stokes equations. The purpose of this contract is to continue the algorithm enhancements of ENSAERO and to apply the code to complicated geometries. During the last year

  2. Development of a new genetic algorithm to solve the feedstock scheduling problem in an anaerobic digester

    NASA Astrophysics Data System (ADS)

    Cram, Ana Catalina

    As worldwide environmental awareness grow, alternative sources of energy have become important to mitigate climate change. Biogas in particular reduces greenhouse gas emissions that contribute to global warming and has the potential of providing 25% of the annual demand for natural gas in the U.S. In 2011, 55,000 metric tons of methane emissions were reduced and 301 metric tons of carbon dioxide emissions were avoided through the use of biogas alone. Biogas is produced by anaerobic digestion through the fermentation of organic material. It is mainly composed of methane with a rage of 50 to 80% in its concentration. Carbon dioxide covers 20 to 50% and small amounts of hydrogen, carbon monoxide and nitrogen. The biogas production systems are anaerobic digestion facilities and the optimal operation of an anaerobic digester requires the scheduling of all batches from multiple feedstocks during a specific time horizon. The availability times, biomass quantities, biogas production rates and storage decay rates must all be taken into account for maximal biogas production to be achieved during the planning horizon. Little work has been done to optimize the scheduling of different types of feedstock in anaerobic digestion facilities to maximize the total biogas produced by these systems. Therefore, in the present thesis, a new genetic algorithm is developed with the main objective of obtaining the optimal sequence in which different feedstocks will be processed and the optimal time to allocate to each feedstock in the digester with the main objective of maximizing the production of biogas considering different types of feedstocks, arrival times and decay rates. Moreover, all batches need to be processed in the digester in a specified time with the restriction that only one batch can be processed at a time. The developed algorithm is applied to 3 different examples and a comparison with results obtained in previous studies is presented.

  3. Developing Multiple Diverse Potential Designs for Heat Transfer Utilizing Graph Based Evolutionary Algorithms

    SciTech Connect

    David J. Muth Jr.

    2006-09-01

    This paper examines the use of graph based evolutionary algorithms (GBEAs) to find multiple acceptable solutions for heat transfer in engineering systems during the optimization process. GBEAs are a type of evolutionary algorithm (EA) in which a topology, or geography, is imposed on an evolving population of solutions. The rates at which solutions can spread within the population are controlled by the choice of topology. As in nature geography can be used to develop and sustain diversity within the solution population. Altering the choice of graph can create a more or less diverse population of potential solutions. The choice of graph can also affect the convergence rate for the EA and the number of mating events required for convergence. The engineering system examined in this paper is a biomass fueled cookstove used in developing nations for household cooking. In this cookstove wood is combusted in a small combustion chamber and the resulting hot gases are utilized to heat the stove’s cooking surface. The spatial temperature profile of the cooking surface is determined by a series of baffles that direct the flow of hot gases. The optimization goal is to find baffle configurations that provide an even temperature distribution on the cooking surface. Often in engineering, the goal of optimization is not to find the single optimum solution but rather to identify a number of good solutions that can be used as a starting point for detailed engineering design. Because of this a key aspect of evolutionary optimization is the diversity of the solutions found. The key conclusion in this paper is that GBEA’s can be used to create multiple good solutions needed to support engineering design.

  4. Algorithms and Algorithmic Languages.

    ERIC Educational Resources Information Center

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

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

  5. Body wall development in lamprey and a new perspective on the origin of vertebrate paired fins.

    PubMed

    Tulenko, Frank J; McCauley, David W; Mackenzie, Ethan L; Mazan, Sylvie; Kuratani, Shigeru; Sugahara, Fumiaki; Kusakabe, Rie; Burke, Ann C

    2013-07-16

    Classical hypotheses regarding the evolutionary origin of paired appendages propose transformation of precursor structures (gill arches and lateral fin folds) into paired fins. During development, gnathostome paired appendages form as outgrowths of body wall somatopleure, a tissue composed of somatic lateral plate mesoderm (LPM) and overlying ectoderm. In amniotes, LPM contributes connective tissue to abaxial musculature and forms ventrolateral dermis of the interlimb body wall. The phylogenetic distribution of this character is uncertain because lineage analyses of LPM have not been generated in anamniotes. We focus on the evolutionary history of the somatopleure to gain insight into the tissue context in which paired fins first appeared. Lampreys diverged from other vertebrates before the acquisition of paired fins and provide a model for investigating the preappendicular condition. We present vital dye fate maps that suggest the somatopleure is eliminated in lamprey as the LPM is separated from the ectoderm and sequestered to the coelomic linings during myotome extension. We also examine the distribution of postcranial mesoderm in catshark and axolotl. In contrast to lamprey, our findings support an LPM contribution to the trunk body wall of these taxa, which is similar to published data for amniotes. Collectively, these data lead us to hypothesize that a persistent somatopleure in the lateral body wall is a gnathostome synapomorphy, and the redistribution of LPM was a key step in generating the novel developmental module that ultimately produced paired fins. These embryological criteria can refocus arguments on paired fin origins and generate hypotheses testable by comparative studies on the source, sequence, and extent of genetic redeployment. PMID:23818600

  6. Stem cell plasticity in development and cancer: epigenetic origin of cancer stem cells.

    PubMed

    Shah, Mansi; Allegrucci, Cinzia

    2013-01-01

    Stem cells are unique cells that can self-renew and differentiate into many cell types. Plasticity is a fundamental characteristic of stem cells and it is regulated by reversible epigenetic modifications. Although gene-restriction programs are established during embryonic development when cell lineages are formed, stem cells retain a degree of flexibility that is essential for tissue regeneration. For instance, quiescent adult stem cells can be induced to proliferate and trans-differentiate in response to injury. The same degree of plasticity is observed in cancer, where cancer cells with stem cell characteristics (or cancer stem cells) are formed by transformation of normal stem cells or de-differentiation of somatic cells. Reprogramming experiments with normal somatic cells and cancer cells show that epigenetic landscapes are more plastic than originally thought and that their manipulation can induce changes in cell fate. Our knowledge of stem cell function is still limited and only by understanding the mechanisms regulating developmental potential together with the definition of epigenetic maps of normal and diseased tissues we can reveal the true extent of their plasticity. In return, the control of plastic epigenetic programs in stem cells will allow us to develop effective treatments for degenerative diseases and cancer. PMID:23150267

  7. Production of proxy datasets in support of GOES-R algorithm development

    NASA Astrophysics Data System (ADS)

    Hillger, Don; Brummer, Renate; Grasso, Louie; Sengupta, Manajit; DeMaria, Robert; DeMaria, Mark

    2009-08-01

    Realistic simulated satellite imagery for GOES-R ABI using state of the art mesoscale modeling and accurate radiative transfer is being produced at the Cooperative Institute for Research in the Atmosphere (CIRA) and used in developing and testing new products. Products which have been produced in support of the GOES-R Algorithm Working Group (AWG) include 6-hour imagery at 5 minute intervals for 4 GOES-R ABI bands (2.25 μm, 3.9 μm, 10.35 μm, and 11.2 μm) that include fire hotspots. The imagery was initially produced at 400 m resolution and a point-spread function applied on the data to create ABI resolution imagery. Also created was corresponding imagery for current GOES at 2 bands (3.9 μm and 10.7 μm). These fire hotspots were simulated for 4 different cases over Kansas, Central America, and California. Additionally, high quality imagery for 10 GOES-R ABI bands (3.9 μm and higher) were produced for 4 extreme weather events. These simulations include a lake effect snow case, a severe weather case, Hurricane Wilma, and Hurricane Lili. All simulations for extreme weather events were also performed for current GOES and compared with available imagery for quality control purposes. Future work focuses on the creation of additional fire proxy datasets including true-color imagery for 3 ABI visible bands. This project also supports the GOES-R AWG Aviation Team in their effort to test their convective initiation algorithm by providing simulated ABI datasets for bands between 2.25 μm and 13.3 μm for a severe weather case. In addition, simulated ABI was generated from MSG infrared (IR) window band imagery and corresponding simulated ABI for the 7 tropical cyclones from 2006-2008 that became hurricanes in the east Atlantic for evaluation of the GOES-R ADT algorithm conducted by the University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (CIMSS).

  8. Development of a Near-Real Time Hail Damage Swath Identification Algorithm for Vegetation

    NASA Technical Reports Server (NTRS)

    Bell, Jordan R.; Molthan, Andrew L.; Schultz, Lori A.; McGrath, Kevin M.; Burks, Jason E.

    2015-01-01

    The Midwest is home to one of the world's largest agricultural growing regions. Between the time period of late May through early September, and with irrigation and seasonal rainfall these crops are able to reach their full maturity. Using moderate to high resolution remote sensors, the monitoring of the vegetation can be achieved using the red and near-infrared wavelengths. These wavelengths allow for the calculation of vegetation indices, such as Normalized Difference Vegetation Index (NDVI). The vegetation growth and greenness, in this region, grows and evolves uniformly as the growing season progresses. However one of the biggest threats to Midwest vegetation during the time period is thunderstorms that bring large hail and damaging winds. Hail and wind damage to crops can be very expensive to crop growers and, damage can be spread over long swaths associated with the tracks of the damaging storms. Damage to the vegetation can be apparent in remotely sensed imagery and is visible from space after storms slightly damage the crops, allowing for changes to occur slowly over time as the crops wilt or more readily apparent if the storms strip material from the crops or destroy them completely. Previous work on identifying these hail damage swaths used manual interpretation by the way of moderate and higher resolution satellite imagery. With the development of an automated and near-real time hail swath damage identification algorithm, detection can be improved, and more damage indicators be created in a faster and more efficient way. The automated detection of hail damage swaths will examine short-term, large changes in the vegetation by differencing near-real time eight day NDVI composites and comparing them to post storm imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard Terra and Aqua and Visible Infrared Imaging Radiometer Suite (VIIRS) aboard Suomi NPP. In addition land surface temperatures from these instruments will be examined as

  9. Development of algorithms for capacitance imaging techniques for fluidized bed flow fields. 1990 Annual report

    SciTech Connect

    Loudin, W.J.

    1991-01-01

    The objective of this research is to provide support for the instrumentation concept of a High Resolution Capacitance Imaging System (HRCIS). The work involves the development and evaluation of the mathematical theory and associated models and algorithms which reduce the electronic measurements to valid physical characterizations. The research and development require the investigation of techniques to solve large systems of equations based on capacitance measurements for various electrode configurations in order to estimate densities of materials in a cross-section of a fluidized bed. Capacitance measurements are made for 400 connections of the 32-electrode system; 400 corresponding electric-field curves are constructed by solving a second order partial differential equation. These curves are used to partition the circular disk into 193 regions called pixels, and the density of material in each pixel is to be estimated. Two methods of approximating densities have been developed and consideration of a third method has been initiated. One method (Method 1) is based on products of displacement currents for intersecting electric-field curves on a cross section. For each pixel one point of intersection is chosen, and the product of the capacitance measurements is found. Both the product and the square-root-of-product seem to yield good relative distribution of densities.

  10. Development of algorithms for capacitance imaging techniques for fluidized bed flow fields

    SciTech Connect

    Loudin, W.J.

    1991-01-01

    The objective of this research is to provide support for the instrumentation concept of a High Resolution Capacitance Imaging System (HRCIS). The work involves the development and evaluation of the mathematical theory and associated models and algorithms which reduce the electronic measurements to valid physical characterizations. The research and development require the investigation of techniques to solve large systems of equations based on capacitance measurements for various electrode configurations in order to estimate densities of materials in a cross-section of a fluidized bed. Capacitance measurements are made for 400 connections of the 32-electrode system; 400 corresponding electric-field curves are constructed by solving a second order partial differential equation. These curves are used to partition the circular disk into 193 regions called pixels, and the density of material in each pixel is to be estimated. Two methods of approximating densities have been developed and consideration of a third method has been initiated. One method (Method 1) is based on products of displacement currents for intersecting electric-field curves on a cross section. For each pixel one point of intersection is chosen, and the product of the capacitance measurements is found. Both the product and the square-root-of-product seem to yield good relative distribution of densities.

  11. Innovative approach in the development of computer assisted algorithm for spine pedicle screw placement.

    PubMed

    Solitro, Giovanni F; Amirouche, Farid

    2016-04-01

    Pedicle screws are typically used for fusion, percutaneous fixation, and means of gripping a spinal segment. The screws act as a rigid and stable anchor points to bridge and connect with a rod as part of a construct. The foundation of the fusion is directly related to the placement of these screws. Malposition of pedicle screws causes intraoperative complications such as pedicle fractures and dural lesions and is a contributing factor to fusion failure. Computer assisted spine surgery (CASS) and patient-specific drill templates were developed to reduce this failure rate, but the trajectory of the screws remains a decision driven by anatomical landmarks often not easily defined. Current data shows the need of a robust and reliable technique that prevents screw misplacement. Furthermore, there is a need to enhance screw insertion guides to overcome the distortion of anatomical landmarks, which is viewed as a limiting factor by current techniques. The objective of this study is to develop a method and mathematical lemmas that are fundamental to the development of computer algorithms for pedicle screw placement. Using the proposed methodology, we show how we can generate automated optimal safe screw insertion trajectories based on the identification of a set of intrinsic parameters. The results, obtained from the validation of the proposed method on two full thoracic segments, are similar to previous morphological studies. The simplicity of the method, being pedicle arch based, is applicable to vertebrae where landmarks are either not well defined, altered or distorted. PMID:26922675

  12. The development of a near-real time hail damage swath identification algorithm for vegetation

    NASA Astrophysics Data System (ADS)

    Bell, Jordan R.

    The central United States is primarily covered in agricultural lands with a growing season that peaks during the same time as the region's climatological maximum for severe weather. These severe thunderstorms can bring large hail that can cause extensive areas of crop damage, which can be difficult to survey from the ground. Satellite remote sensing can help with the identification of these damaged areas. This study examined three techniques for identifying damage using satellite imagery that could be used in the development of a near-real time algorithm formulated for the detection of damage to agriculture caused by hail. The three techniques: a short term Normalized Difference Vegetation Index (NDVI) change product, a modified Vegetation Health Index (mVHI) that incorporates both NDVI and land surface temperature (LST), and a feature detection technique based on NDVI and LST anomalies were tested on a single training case and five case studies. Skill scores were computed for each of the techniques during the training case and each case study. Among the best-performing case studies, the probability of detection (POD) for the techniques ranged from 0.527 - 0.742. Greater skill was noted for environments that occurred later in the growing season over areas where the land cover was consistently one or two types of uniform vegetation. The techniques struggled in environments where the land cover was not able to provide uniform vegetation, resulting in POD of 0.067 - 0.223. The feature detection technique was selected to be used for the near-real-time algorithm, based on the consistent performance throughout the entire growing season.

  13. Development of the Tardivo Algorithm to Predict Amputation Risk of Diabetic Foot

    PubMed Central

    Tardivo, João Paulo; Baptista, Maurício S.; Correa, João Antonio; Adami, Fernando; Pinhal, Maria Aparecida Silva

    2015-01-01

    Diabetes is a chronic disease that affects almost 19% of the elderly population in Brazil and similar percentages around the world. Amputation of lower limbs in diabetic patients who present foot complications is a common occurrence with a significant reduction of life quality, and heavy costs on the health system. Unfortunately, there is no easy protocol to define the conditions that should be considered to proceed to amputation. The main objective of the present study is to create a simple prognostic score to evaluate the diabetic foot, which is called Tardivo Algorithm. Calculation of the score is based on three main factors: Wagner classification, signs of peripheral arterial disease (PAD), which is evaluated by using Peripheral Arterial Disease Classification, and the location of ulcers. The final score is obtained by multiplying the value of the individual factors. Patients with good peripheral vascularization received a value of 1, while clinical signs of ischemia received a value of 2 (PAD 2). Ulcer location was defined as forefoot, midfoot and hind foot. The conservative treatment used in patients with scores below 12 was based on a recently developed Photodynamic Therapy (PDT) protocol. 85.5% of these patients presented a good outcome and avoided amputation. The results showed that scores 12 or higher represented a significantly higher probability of amputation (Odds ratio and logistic regression-IC 95%, 12.2–1886.5). The Tardivo algorithm is a simple prognostic score for the diabetic foot, easily accessible by physicians. It helps to determine the amputation risk and the best treatment, whether it is conservative or surgical management. PMID:26281044

  14. Development and validation of a simple algorithm for initiation of CPAP in neonates with respiratory distress in Malawi

    PubMed Central

    Hundalani, Shilpa G; Richards-Kortum, Rebecca; Oden, Maria; Kawaza, Kondwani; Gest, Alfred; Molyneux, Elizabeth

    2015-01-01

    Background Low-cost bubble continuous positive airway pressure (bCPAP) systems have been shown to improve survival in neonates with respiratory distress, in developing countries including Malawi. District hospitals in Malawi implementing CPAP requested simple and reliable guidelines to enable healthcare workers with basic skills and minimal training to determine when treatment with CPAP is necessary. We developed and validated TRY (T: Tone is good, R: Respiratory Distress and Y=Yes) CPAP, a simple algorithm to identify neonates with respiratory distress who would benefit from CPAP. Objective To validate the TRY CPAP algorithm for neonates with respiratory distress in a low-resource setting. Methods We constructed an algorithm using a combination of vital signs, tone and birth weight to determine the need for CPAP in neonates with respiratory distress. Neonates admitted to the neonatal ward of Queen Elizabeth Central Hospital, in Blantyre, Malawi, were assessed in a prospective, cross-sectional study. Nurses and paediatricians-in-training assessed neonates to determine whether they required CPAP using the TRY CPAP algorithm. To establish the accuracy of the TRY CPAP algorithm in evaluating the need for CPAP, their assessment was compared with the decision of a neonatologist blinded to the TRY CPAP algorithm findings. Results 325 neonates were evaluated over a 2-month period; 13% were deemed to require CPAP by the neonatologist. The inter-rater reliability with the algorithm was 0.90 for nurses and 0.97 for paediatricians-in-training using the neonatologist's assessment as the reference standard. Conclusions The TRY CPAP algorithm has the potential to be a simple and reliable tool to assist nurses and clinicians in identifying neonates who require treatment with CPAP in low-resource settings. PMID:25877290

  15. [The origin, diffusion and development of healing doctrines in medical history--exemplified by homeopathy].

    PubMed

    Schmidt, Josef M

    2007-01-01

    As a paradigmatic case study of the origin, spread, and development of medical systems, this paper investigates the 200-years history of homeopathy from different perspectives of medical history. On the basis of new research on Samuel Hahnemann (1755-1843), first, a concise and critical overview on the principles, explanations, and implications of his doctrine is presented. The historical, conceptual, and social background of the founder of homeopathy is then elaborated in terms of history of medicine, science, philosophy, sociology, culture, and ideas, as well as theory of science, theory of communication, and sociology of science. The process of the world wide spread of homeopathy is examined from different points of view, ranging from history of heroes, institutions, professionalisation, politics, economics, religion, and organisations to history of patients, perception, and semiotics. Finally, a comparative approach to the different development and status of homeopathy in different countries results in the extraction of a set of crucial variables, such as charismatic personage, influential patronage, economic sponsorship, political protection, media support, and patients' demand, which might explane a major part of these differences. Eventually, the notorious splits of homeopathy's doctrine suggest the idea that--in analogy to theory of evolution--a variety of concurrent strains (rather than one monolithic block) of a doctrine may prove to be a kind of advantage for survival. In conclusion, acceptance and relevance of medical systems are determined by many factors. Since external ones are usually outweighing internal ones, medical history may offer a broader and more comprehensive understanding of the dynamics of their spread and development than clinical trials and scientific objection alone.

  16. Calibration and algorithm development for estimation of nitrogen in wheat crop using tractor mounted N-sensor.

    PubMed

    Singh, Manjeet; Kumar, Rajneesh; Sharma, Ankit; Singh, Bhupinder; Thind, S K

    2015-01-01

    The experiment was planned to investigate the tractor mounted N-sensor (Make Yara International) to predict nitrogen (N) for wheat crop under different nitrogen levels. It was observed that, for tractor mounted N-sensor, spectrometers can scan about 32% of total area of crop under consideration. An algorithm was developed using a linear relationship between sensor sufficiency index (SIsensor) and SISPAD to calculate the N app as a function of SISPAD. There was a strong correlation among sensor attributes (sensor value, sensor biomass, and sensor NDVI) and different N-levels. It was concluded that tillering stage is most prominent stage to predict crop yield as compared to the other stages by using sensor attributes. The algorithms developed for tillering and booting stages are useful for the prediction of N-application rates for wheat crop. N-application rates predicted by algorithm developed and sensor value were almost the same for plots with different levels of N applied. PMID:25811039

  17. Calibration and Algorithm Development for Estimation of Nitrogen in Wheat Crop Using Tractor Mounted N-Sensor

    PubMed Central

    Singh, Manjeet; Kumar, Rajneesh; Sharma, Ankit; Singh, Bhupinder; Thind, S. K.

    2015-01-01

    The experiment was planned to investigate the tractor mounted N-sensor (Make Yara International) to predict nitrogen (N) for wheat crop under different nitrogen levels. It was observed that, for tractor mounted N-sensor, spectrometers can scan about 32% of total area of crop under consideration. An algorithm was developed using a linear relationship between sensor sufficiency index (SIsensor) and SISPAD to calculate the Napp as a function of SISPAD. There was a strong correlation among sensor attributes (sensor value, sensor biomass, and sensor NDVI) and different N-levels. It was concluded that tillering stage is most prominent stage to predict crop yield as compared to the other stages by using sensor attributes. The algorithms developed for tillering and booting stages are useful for the prediction of N-application rates for wheat crop. N-application rates predicted by algorithm developed and sensor value were almost the same for plots with different levels of N applied. PMID:25811039

  18. Accessing primary care Big Data: the development of a software algorithm to explore the rich content of consultation records

    PubMed Central

    MacRae, J; Darlow, B; McBain, L; Jones, O; Stubbe, M; Turner, N; Dowell, A

    2015-01-01

    Objective To develop a natural language processing software inference algorithm to classify the content of primary care consultations using electronic health record Big Data and subsequently test the algorithm's ability to estimate the prevalence and burden of childhood respiratory illness in primary care. Design Algorithm development and validation study. To classify consultations, the algorithm is designed to interrogate clinical narrative entered as free text, diagnostic (Read) codes created and medications prescribed on the day of the consultation. Setting Thirty-six consenting primary care practices from a mixed urban and semirural region of New Zealand. Three independent sets of 1200 child consultation records were randomly extracted from a data set of all general practitioner consultations in participating practices between 1 January 2008–31 December 2013 for children under 18 years of age (n=754 242). Each consultation record within these sets was independently classified by two expert clinicians as respiratory or non-respiratory, and subclassified according to respiratory diagnostic categories to create three ‘gold standard’ sets of classified records. These three gold standard record sets were used to train, test and validate the algorithm. Outcome measures Sensitivity, specificity, positive predictive value and F-measure were calculated to illustrate the algorithm's ability to replicate judgements of expert clinicians within the 1200 record gold standard validation set. Results The algorithm was able to identify respiratory consultations in the 1200 record validation set with a sensitivity of 0.72 (95% CI 0.67 to 0.78) and a specificity of 0.95 (95% CI 0.93 to 0.98). The positive predictive value of algorithm respiratory classification was 0.93 (95% CI 0.89 to 0.97). The positive predictive value of the algorithm classifying consultations as being related to specific respiratory diagnostic categories ranged from 0.68 (95% CI 0.40 to 1.00; other

  19. Ice surface temperature retrieval from AVHRR, ATSR, and passive microwave satellite data: Algorithm development and application

    NASA Technical Reports Server (NTRS)

    Key, Jeff; Maslanik, James; Steffen, Konrad

    1994-01-01

    One essential parameter used in the estimation of radiative and turbulent heat fluxes from satellite data is surface temperature. Sea and land surface temperature (SST and LST) retrieval algorithms that utilize the thermal infrared portion of the spectrum have been developed, with the degree of success dependent primarily upon the variability of the surface and atmospheric characteristics. However, little effort has been directed to the retrieval of the sea ice surface temperature (IST) in the Arctic and Antarctic pack ice or the ice sheet surface temperature over Antarctica and Greenland. The reason is not one of methodology, but rather our limited knowledge of atmospheric temperature, humidity, and aerosol vertical, spatial and temporal distributions, the microphysical properties of polar clouds, and the spectral characteristics of snow, ice, and water surfaces. Over the open ocean the surface is warm, dark, and relatively homogeneous. This makes SST retrieval, including cloud clearing, a fairly straightforward task. Over the ice, however, the surface within a single satellite pixel is likely to be highly heterogeneous, a mixture of ice of various thicknesses, open water, and snow cover in the case of sea ice. Additionally, the Arctic is cloudy - very cloudy - with typical cloud cover amounts ranging from 60-90 percent. There are few observations of cloud cover amounts over Antarctica. The goal of this research is to increase our knowledge of surface temperature patterns and magnitudes in both polar regions, by examining existing data and improving our ability to use satellite data as a monitoring tool. Four instruments are of interest in this study: the AVHRR, ATSR, SMMR, and SSM/I. Our objectives are as follows. Refine the existing AVHRR retrieval algorithm defined in Key and Haefliger (1992; hereafter KH92) and applied elsewhere. Develop a method for IST retrieval from ATSR data similar to the one used for SST. Further investigate the possibility of estimating

  20. The Age Specific Incidence Anomaly Suggests that Cancers Originate During Development

    NASA Astrophysics Data System (ADS)

    Brody, James P.

    2014-05-01

    The accumulation of genetic alterations causes cancers. Since this accumulation takes time, the incidence of most cancers is thought to increase exponentially with age. However, careful measurements of the age-specific incidence show that the specific incidence for many forms of cancer rises with age to a maximum, and then decreases. This decrease in the age-specific incidence with age is an anomaly. Understanding this anomaly should lead to a better understanding of how tumors develop and grow. Here we derive the shape of the age-specific incidence, showing that it should follow the shape of a Weibull distribution. Measurements indicate that the age-specific incidence for colon cancer does indeed follow a Weibull distribution. This analysis leads to the interpretation that for colon cancer two subpopulations exist in the general population: a susceptible population and an immune population. Colon tumors will only occur in the susceptible population. This analysis is consistent with the developmental origins of disease hypothesis and generalizable to many other common forms of cancer.

  1. The Age Specific Incidence Anomaly Suggests that Cancers Originate During Development

    NASA Astrophysics Data System (ADS)

    Brody, James P.

    The accumulation of genetic alterations causes cancers. Since this accumulation takes time, the incidence of most cancers is thought to increase exponentially with age. However, careful measurements of the age-specific incidence show that the specific incidence for many forms of cancer rises with age to a maximum, and then decreases. This decrease in the age-specific incidence with age is an anomaly. Understanding this anomaly should lead to a better understanding of how tumors develop and grow. Here we derive the shape of the age-specific incidence, showing that it should follow the shape of a Weibull distribution. Measurements indicate that the age-specific incidence for colon cancer does indeed follow a Weibull distribution. This analysis leads to the interpretation that for colon cancer two subpopulations exist in the general population: a susceptible population and an immune population. Colon tumors will only occur in the susceptible population. This analysis is consistent with the developmental origins of disease hypothesis and generalizable to many other common forms of cancer.

  2. A Review: Origins of the Dielectric Properties of Proteins and Potential Development as Bio-Sensors

    PubMed Central

    Bibi, Fabien; Villain, Maud; Guillaume, Carole; Sorli, Brice; Gontard, Nathalie

    2016-01-01

    Polymers can be classified as synthetic polymers and natural polymers, and are often characterized by their most typical functions namely their high mechanical resistivity, electrical conductivity and dielectric properties. This bibliography report consists in: (i) Defining the origins of the dielectric properties of natural polymers by reviewing proteins. Despite their complex molecular chains, proteins present several points of interest, particularly, their charge content conferring their electrical and dielectric properties; (ii) Identifying factors influencing the dielectric properties of protein films. The effects of vapors and gases such as water vapor, oxygen, carbon dioxide, ammonia and ethanol on the dielectric properties are put forward; (iii) Finally, potential development of protein films as bio-sensors coated on electronic devices for detection of environmental changes particularly humidity or carbon dioxide content in relation with dielectric properties variations are discussed. As the study of the dielectric properties implies imposing an electric field to the material, it was necessary to evaluate the impact of frequency on the polymers and subsequently on their structure. Characterization techniques, on the one hand dielectric spectroscopy devoted for the determination of the glass transition temperature among others, and on the other hand other techniques such as infra-red spectroscopy for structure characterization as a function of moisture content for instance are also introduced. PMID:27527179

  3. A Review: Origins of the Dielectric Properties of Proteins and Potential Development as Bio-Sensors.

    PubMed

    Bibi, Fabien; Villain, Maud; Guillaume, Carole; Sorli, Brice; Gontard, Nathalie

    2016-08-04

    Polymers can be classified as synthetic polymers and natural polymers, and are often characterized by their most typical functions namely their high mechanical resistivity, electrical conductivity and dielectric properties. This bibliography report consists in: (i) Defining the origins of the dielectric properties of natural polymers by reviewing proteins. Despite their complex molecular chains, proteins present several points of interest, particularly, their charge content conferring their electrical and dielectric properties; (ii) Identifying factors influencing the dielectric properties of protein films. The effects of vapors and gases such as water vapor, oxygen, carbon dioxide, ammonia and ethanol on the dielectric properties are put forward; (iii) Finally, potential development of protein films as bio-sensors coated on electronic devices for detection of environmental changes particularly humidity or carbon dioxide content in relation with dielectric properties variations are discussed. As the study of the dielectric properties implies imposing an electric field to the material, it was necessary to evaluate the impact of frequency on the polymers and subsequently on their structure. Characterization techniques, on the one hand dielectric spectroscopy devoted for the determination of the glass transition temperature among others, and on the other hand other techniques such as infra-red spectroscopy for structure characterization as a function of moisture content for instance are also introduced.

  4. Not So Rare Earth? New Developments in Understanding the Origin of the Earth and Moon

    NASA Technical Reports Server (NTRS)

    Righter, Kevin

    2007-01-01

    A widely accepted model for the origin of the Earth and Moon has been a somewhat specific giant impact scenario involving an impactor to proto-Earth mass ratio of 3:7, occurring 50-60 Ma after T(sub 0), when the Earth was only half accreted, with the majority of Earth's water then accreted after the main stage of growth, perhaps from comets. There have been many changes to this specific scenario, due to advances in isotopic and trace element geochemistry, more detailed, improved, and realistic giant impact and terrestrial planet accretion modeling, and consideration of terrestrial water sources other than high D/H comets. The current scenario is that the Earth accreted faster and differentiated quickly, the Moon-forming impact could have been mid to late in the accretion process, and water may have been present during accretion. These new developments have broadened the range of conditions required to make an Earth-Moon system, and suggests there may be many new fruitful avenues of research. There are also some classic and unresolved problems such as the significance of the identical O isotopic composition of the Earth and Moon, the depletion of volatiles on the lunar mantle relative to Earth's, the relative contribution of the impactor and proto-Earth to the Moon's mass, and the timing of Earth's possible atmospheric loss relative to the giant impact.

  5. A Review: Origins of the Dielectric Properties of Proteins and Potential Development as Bio-Sensors.

    PubMed

    Bibi, Fabien; Villain, Maud; Guillaume, Carole; Sorli, Brice; Gontard, Nathalie

    2016-01-01

    Polymers can be classified as synthetic polymers and natural polymers, and are often characterized by their most typical functions namely their high mechanical resistivity, electrical conductivity and dielectric properties. This bibliography report consists in: (i) Defining the origins of the dielectric properties of natural polymers by reviewing proteins. Despite their complex molecular chains, proteins present several points of interest, particularly, their charge content conferring their electrical and dielectric properties; (ii) Identifying factors influencing the dielectric properties of protein films. The effects of vapors and gases such as water vapor, oxygen, carbon dioxide, ammonia and ethanol on the dielectric properties are put forward; (iii) Finally, potential development of protein films as bio-sensors coated on electronic devices for detection of environmental changes particularly humidity or carbon dioxide content in relation with dielectric properties variations are discussed. As the study of the dielectric properties implies imposing an electric field to the material, it was necessary to evaluate the impact of frequency on the polymers and subsequently on their structure. Characterization techniques, on the one hand dielectric spectroscopy devoted for the determination of the glass transition temperature among others, and on the other hand other techniques such as infra-red spectroscopy for structure characterization as a function of moisture content for instance are also introduced. PMID:27527179

  6. Examination of a genetic algorithm for the application in high-throughput downstream process development.

    PubMed

    Treier, Katrin; Berg, Annette; Diederich, Patrick; Lang, Katharina; Osberghaus, Anna; Dismer, Florian; Hubbuch, Jürgen

    2012-10-01

    Compared to traditional strategies, application of high-throughput experiments combined with optimization methods can potentially speed up downstream process development and increase our understanding of processes. In contrast to the method of Design of Experiments in combination with response surface analysis (RSA), optimization approaches like genetic algorithms (GAs) can be applied to identify optimal parameter settings in multidimensional optimizations tasks. In this article the performance of a GA was investigated applying parameters applicable in high-throughput downstream process development. The influence of population size, the design of the initial generation and selection pressure on the optimization results was studied. To mimic typical experimental data, four mathematical functions were used for an in silico evaluation. The influence of GA parameters was minor on landscapes with only one optimum. On landscapes with several optima, parameters had a significant impact on GA performance and success in finding the global optimum. Premature convergence increased as the number of parameters and noise increased. RSA was shown to be comparable or superior for simple systems and low to moderate noise. For complex systems or high noise levels, RSA failed, while GA optimization represented a robust tool for process optimization. Finally, the effect of different objective functions is shown exemplarily for a refolding optimization of lysozyme.

  7. Evaluating the administration costs of biologic drugs: development of a cost algorithm.

    PubMed

    Tetteh, Ebenezer K; Morris, Stephen

    2014-12-01

    Biologic drugs, as with all other medical technologies, are subject to a number of regulatory, marketing, reimbursement (financing) and other demand-restricting hurdles applied by healthcare payers. One example is the routine use of cost-effectiveness analyses or health technology assessments to determine which medical technologies offer value-for-money. The manner in which these assessments are conducted suggests that, holding all else equal, the economic value of biologic drugs may be determined by how much is spent on administering these drugs or trade-offs between drug acquisition and administration costs. Yet, on the supply-side, it seems very little attention is given to how manufacturing and formulation choices affect healthcare delivery costs. This paper evaluates variations in the administration costs of biologic drugs, taking care to ensure consistent inclusion of all relevant cost resources. From this, it develops a regression-based algorithm with which manufacturers could possibly predict, during process development, how their manufacturing and formulation choices may impact on the healthcare delivery costs of their products. PMID:26208926

  8. Development of fast line scanning imaging algorithm for diseased chicken detection

    NASA Astrophysics Data System (ADS)

    Yang, Chun-Chieh; Chao, Kuanglin; Chen, Yud-Ren; Kim, Moon S.

    2005-11-01

    A hyperspectral line-scan imaging system for automated inspection of wholesome and diseased chickens was developed and demonstrated. The hyperspectral imaging system consisted of an electron-multiplying charge-coupled-device (EMCCD) camera and an imaging spectrograph. The system used a spectrograph to collect spectral measurements across a pixel-wide vertical linear field of view through which moving chicken carcasses passed. After a series of image calibration procedures, the hyperspectral line-scan images were collected for chickens on a laboratory simulated processing line. From spectral analysis, four key wavebands for differentiating between wholesome and systemically diseased chickens were selected: 413 nm, 472 nm, 515 nm, and 546 nm, and a reference waveband, 622 nm. The ratio of relative reflectance between each key wavelength and the reference wavelength was calculated as an image feature. A fuzzy logic-based algorithm utilizing the key wavebands was developed to identify individual pixels on the chicken surface exhibiting symptoms of systemic disease. Two differentiation methods were built to successfully differentiate 72 systemically diseased chickens from 65 wholesome chickens.

  9. Life origination and development hydrate theory (LOH-Theory) in the context of biological, physicochemical, astrophysical, and paleontological studies

    NASA Astrophysics Data System (ADS)

    Ostrovskii, V. E.; Kadyshevich, E. A.

    2014-04-01

    Till now, we formulated and developed the Life Origination Hydrate Theory (LOH-Theory) and Mitosis and Replication Hydrate Theory (MRHTheory) as the instruments for understanding the physical and chemical mechanisms applied by Nature for the living matter origination and propagation. This work is aimed at coordination of these theories with the paleontological and astrophysical knowledges and hypotheses of the Earth and Solar System remote histories.

  10. NASA's Physics of the Cosmos and Cosmic Origins Technology Development Programs

    NASA Technical Reports Server (NTRS)

    Pham, Thai; Seery, Bernard; Ganel, Opher

    2016-01-01

    The strategic astrophysics missions of the coming decades will help answer the questions "How did our universe begin and evolve?" and "How did galaxies, stars, and planets come to be?" Enabling these missions requires advances in key technologies far beyond the current state of the art. NASA's Physics of the Cosmos (PCOS) and Cosmic Origins (COR) Program Offices manage technology maturation projects funded through the Strategic Astrophysics Technology (SAT) program to accomplish such advances. The PCOS and COR Program Offices, residing at the NASA Goddard Space Flight Center (GSFC), were established in 2011, and serve as the implementation arm for the Astrophysics Division at NASA Headquarters. We present an overview of the Programs' technology development activities and the current technology investment portfolio of 23 technology advancements. We discuss the process for addressing community-provided technology gaps and Technology Management Board (TMB)-vetted prioritization and investment recommendations that inform the SAT program. The process improves the transparency and relevance of our technology investments, provides the community a voice in the process, and promotes targeted external technology investments by defining needs and identifying customers. The Programs' priorities are driven by strategic direction from the Astrophysics Division, which is informed by the National Research Council's (NRC) "New Worlds, New Horizons in Astronomy and Astrophysics" (NWNH) 2010 Decadal Survey report [1], the Astrophysics Implementation Plan (AIP) [2] as updated, and the Astrophysics Roadmap "Enduring Quests, Daring Visions" [3]. These priorities include technology development for missions to study dark energy, gravitational waves, X-ray and inflation probe science, and large far-infrared (IR) and ultraviolet (UV)/optical/IR telescopes to conduct imaging and spectroscopy studies. The SAT program is the Astrophysics Division's main investment method to mature technologies

  11. Development of an Innovative Algorithm for Aerodynamics-Structure Interaction Using Lattice Boltzmann Method

    NASA Technical Reports Server (NTRS)

    Mei, Ren-Wei; Shyy, Wei; Yu, Da-Zhi; Luo, Li-Shi; Rudy, David (Technical Monitor)

    2001-01-01

    The lattice Boltzmann equation (LBE) is a kinetic formulation which offers an alternative computational method capable of solving fluid dynamics for various systems. Major advantages of the method are owing to the fact that the solution for the particle distribution functions is explicit, easy to implement, and the algorithm is natural to parallelize. In this final report, we summarize the works accomplished in the past three years. Since most works have been published, the technical details can be found in the literature. Brief summary will be provided in this report. In this project, a second-order accurate treatment of boundary condition in the LBE method is developed for a curved boundary and tested successfully in various 2-D and 3-D configurations. To evaluate the aerodynamic force on a body in the context of LBE method, several force evaluation schemes have been investigated. A simple momentum exchange method is shown to give reliable and accurate values for the force on a body in both 2-D and 3-D cases. Various 3-D LBE models have been assessed in terms of efficiency, accuracy, and robustness. In general, accurate 3-D results can be obtained using LBE methods. The 3-D 19-bit model is found to be the best one among the 15-bit, 19-bit, and 27-bit LBE models. To achieve desired grid resolution and to accommodate the far field boundary conditions in aerodynamics computations, a multi-block LBE method is developed by dividing the flow field into various blocks each having constant lattice spacing. Substantial contribution to the LBE method is also made through the development of a new, generalized lattice Boltzmann equation constructed in the moment space in order to improve the computational stability, detailed theoretical analysis on the stability, dispersion, and dissipation characteristics of the LBE method, and computational studies of high Reynolds number flows with singular gradients. Finally, a finite difference-based lattice Boltzmann method is

  12. Development and verification of an analytical algorithm to predict absorbed dose distributions in ocular proton therapy using Monte Carlo simulations.

    PubMed

    Koch, Nicholas C; Newhauser, Wayne D

    2010-02-01

    Proton beam radiotherapy is an effective and non-invasive treatment for uveal melanoma. Recent research efforts have focused on improving the dosimetric accuracy of treatment planning and overcoming the present limitation of relative analytical dose calculations. Monte Carlo algorithms have been shown to accurately predict dose per monitor unit (D/MU) values, but this has yet to be shown for analytical algorithms dedicated to ocular proton therapy, which are typically less computationally expensive than Monte Carlo algorithms. The objective of this study was to determine if an analytical method could predict absolute dose distributions and D/MU values for a variety of treatment fields like those used in ocular proton therapy. To accomplish this objective, we used a previously validated Monte Carlo model of an ocular nozzle to develop an analytical algorithm to predict three-dimensional distributions of D/MU values from pristine Bragg peaks and therapeutically useful spread-out Bragg peaks (SOBPs). Results demonstrated generally good agreement between the analytical and Monte Carlo absolute dose calculations. While agreement in the proximal region decreased for beams with less penetrating Bragg peaks compared with the open-beam condition, the difference was shown to be largely attributable to edge-scattered protons. A method for including this effect in any future analytical algorithm was proposed. Comparisons of D/MU values showed typical agreement to within 0.5%. We conclude that analytical algorithms can be employed to accurately predict absolute proton dose distributions delivered by an ocular nozzle.

  13. Development of a deformable dosimetric phantom to verify dose accumulation algorithms for adaptive radiotherapy

    PubMed Central

    Zhong, Hualiang; Adams, Jeffrey; Glide-Hurst, Carri; Zhang, Hualin; Li, Haisen; Chetty, Indrin J.

    2016-01-01

    Adaptive radiotherapy may improve treatment outcomes for lung cancer patients. Because of the lack of an effective tool for quality assurance, this therapeutic modality is not yet accepted in clinic. The purpose of this study is to develop a deformable physical phantom for validation of dose accumulation algorithms in regions with heterogeneous mass. A three-dimensional (3D) deformable phantom was developed containing a tissue-equivalent tumor and heterogeneous sponge inserts. Thermoluminescent dosimeters (TLDs) were placed at multiple locations in the phantom each time before dose measurement. Doses were measured with the phantom in both the static and deformed cases. The deformation of the phantom was actuated by a motor driven piston. 4D computed tomography images were acquired to calculate 3D doses at each phase using Pinnacle and EGSnrc/DOSXYZnrc. These images were registered using two registration software packages: VelocityAI and Elastix. With the resultant displacement vector fields (DVFs), the calculated 3D doses were accumulated using a mass-and energy congruent mapping method and compared to those measured by the TLDs at four typical locations. In the static case, TLD measurements agreed with all the algorithms by 1.8% at the center of the tumor volume and by 4.0% in the penumbra. In the deformable case, the phantom's deformation was reproduced within 1.1 mm. For the 3D dose calculated by Pinnacle, the total dose accumulated with the Elastix DVF agreed well to the TLD measurements with their differences <2.5% at four measured locations. When the VelocityAI DVF was used, their difference increased up to 11.8%. For the 3D dose calculated by EGSnrc/DOSXYZnrc, the total doses accumulated with the two DVFs were within 5.7% of the TLD measurements which are slightly over the rate of 5% for clinical acceptance. The detector-embedded deformable phantom allows radiation dose to be measured in a dynamic environment, similar to deforming lung tissues, supporting

  14. Development of a deformable dosimetric phantom to verify dose accumulation algorithms for adaptive radiotherapy.

    PubMed

    Zhong, Hualiang; Adams, Jeffrey; Glide-Hurst, Carri; Zhang, Hualin; Li, Haisen; Chetty, Indrin J

    2016-01-01

    Adaptive radiotherapy may improve treatment outcomes for lung cancer patients. Because of the lack of an effective tool for quality assurance, this therapeutic modality is not yet accepted in clinic. The purpose of this study is to develop a deformable physical phantom for validation of dose accumulation algorithms in regions with heterogeneous mass. A three-dimensional (3D) deformable phantom was developed containing a tissue-equivalent tumor and heterogeneous sponge inserts. Thermoluminescent dosimeters (TLDs) were placed at multiple locations in the phantom each time before dose measurement. Doses were measured with the phantom in both the static and deformed cases. The deformation of the phantom was actuated by a motor driven piston. 4D computed tomography images were acquired to calculate 3D doses at each phase using Pinnacle and EGSnrc/DOSXYZnrc. These images were registered using two registration software packages: VelocityAI and Elastix. With the resultant displacement vector fields (DVFs), the calculated 3D doses were accumulated using a mass-and energy congruent mapping method and compared to those measured by the TLDs at four typical locations. In the static case, TLD measurements agreed with all the algorithms by 1.8% at the center of the tumor volume and by 4.0% in the penumbra. In the deformable case, the phantom's deformation was reproduced within 1.1 mm. For the 3D dose calculated by Pinnacle, the total dose accumulated with the Elastix DVF agreed well to the TLD measurements with their differences <2.5% at four measured locations. When the VelocityAI DVF was used, their difference increased up to 11.8%. For the 3D dose calculated by EGSnrc/DOSXYZnrc, the total doses accumulated with the two DVFs were within 5.7% of the TLD measurements which are slightly over the rate of 5% for clinical acceptance. The detector-embedded deformable phantom allows radiation dose to be measured in a dynamic environment, similar to deforming lung tissues, supporting

  15. Utilization of Ancillary Data Sets for Conceptual SMAP Mission Algorithm Development and Product Generation

    NASA Technical Reports Server (NTRS)

    O'Neill, P.; Podest, E.

    2011-01-01

    The planned Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey, Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond [1]. Scheduled to launch late in 2014, the proposed SMAP mission would provide high resolution and frequent revisit global mapping of soil moisture and freeze/thaw state, utilizing enhanced Radio Frequency Interference (RFI) mitigation approaches to collect new measurements of the hydrological condition of the Earth's surface. The SMAP instrument design incorporates an L-band radar (3 km) and an L band radiometer (40 km) sharing a single 6-meter rotating mesh antenna to provide measurements of soil moisture and landscape freeze/thaw state [2]. These observations would (1) improve our understanding of linkages between the Earth's water, energy, and carbon cycles, (2) benefit many application areas including numerical weather and climate prediction, flood and drought monitoring, agricultural productivity, human health, and national security, (3) help to address priority questions on climate change, and (4) potentially provide continuity with brightness temperature and soil moisture measurements from ESA's SMOS (Soil Moisture Ocean Salinity) and NASA's Aquarius missions. In the planned SMAP mission prelaunch time frame, baseline algorithms are being developed for generating (1) soil moisture products both from radiometer measurements on a 36 km grid and from combined radar/radiometer measurements on a 9 km grid, and (2) freeze/thaw products from radar measurements on a 3 km grid. These retrieval algorithms need a variety of global ancillary data, both static and dynamic, to run the retrieval models, constrain the retrievals, and provide flags for indicating retrieval quality. The choice of which ancillary dataset to use for a particular SMAP product would be based on a number of factors

  16. Development of an algorithm for heartbeats detection and classification in Holter records based on temporal and morphological features

    NASA Astrophysics Data System (ADS)

    García, A.; Romano, H.; Laciar, E.; Correa, R.

    2011-12-01

    In this work a detection and classification algorithm for heartbeats analysis in Holter records was developed. First, a QRS complexes detector was implemented and their temporal and morphological characteristics were extracted. A vector was built with these features; this vector is the input of the classification module, based on discriminant analysis. The beats were classified in three groups: Premature Ventricular Contraction beat (PVC), Atrial Premature Contraction beat (APC) and Normal Beat (NB). These beat categories represent the most important groups of commercial Holter systems. The developed algorithms were evaluated in 76 ECG records of two validated open-access databases "arrhythmias MIT BIH database" and "MIT BIH supraventricular arrhythmias database". A total of 166343 beats were detected and analyzed, where the QRS detection algorithm provides a sensitivity of 99.69 % and a positive predictive value of 99.84 %. The classification stage gives sensitivities of 97.17% for NB, 97.67% for PCV and 92.78% for APC.

  17. Decoding neural events from fMRI BOLD signal: a comparison of existing approaches and development of a new algorithm.

    PubMed

    Bush, Keith; Cisler, Josh

    2013-07-01

    Neuroimaging methodology predominantly relies on the blood oxygenation level dependent (BOLD) signal. While the BOLD signal is a valid measure of neuronal activity, variances in fluctuations of the BOLD signal are not only due to fluctuations in neural activity. Thus, a remaining problem in neuroimaging analyses is developing methods that ensure specific inferences about neural activity that are not confounded by unrelated sources of noise in the BOLD signal. Here, we develop and test a new algorithm for performing semiblind (i.e., no knowledge of stimulus timings) deconvolution of the BOLD signal that treats the neural event as an observable, but intermediate, probabilistic representation of the system's state. We test and compare this new algorithm against three other recent deconvolution algorithms under varied levels of autocorrelated and Gaussian noise, hemodynamic response function (HRF) misspecification and observation sampling rate. Further, we compare the algorithms' performance using two models to simulate BOLD data: a convolution of neural events with a known (or misspecified) HRF versus a biophysically accurate balloon model of hemodynamics. We also examine the algorithms' performance on real task data. The results demonstrated good performance of all algorithms, though the new algorithm generally outperformed the others (3.0% improvement) under simulated resting-state experimental conditions exhibiting multiple, realistic confounding factors (as well as 10.3% improvement on a real Stroop task). The simulations also demonstrate that the greatest negative influence on deconvolution accuracy is observation sampling rate. Practical and theoretical implications of these results for improving inferences about neural activity from fMRI BOLD signal are discussed.

  18. Algorithm development for the retrieval of coastal water constituents from satellite Modular Optoelectronic Scanner images

    NASA Astrophysics Data System (ADS)

    Hetscher, Matthias; Krawczyk, Harald; Neumann, Andreas; Walzel, Thomas; Zimmermann, Gerhard

    1997-10-01

    DLR's imaging spectrometer the Modular Optoelectronic Scanner (MOS) on the Indian remote sensing satellite IRS-P3 has been orbiting since March 1996. MOS consists of two spectrometers, one narrow band spectrometer around 760 nm for retrieval of atmospheric parameters and a second one in the IVS/NIR region with an additional line camera at 1,6 micrometers . The instrument was especially designed for the remote sensing of coastal zone water and the determination and distinction of its constituents. MOS was developed and manufactured at the Institute of Space Sensor Technology (ISST) and launched in a joint effort with the Indian Space Research Organization (ISRO). The high spectral resolution of MOS offers the possibility of using the differences in spectral signatures of remote sensing objects for quantitative determination of geophysical parameters. In ISST a linear estimator to derive water constituents and aerosol optical thickness has been developed, exploiting Principal Component Inversion (PCI) of modeled top-of- atmosphere and experimental radiance data sets. The estimator results in sets of weighting coefficients for each measurement band, depending on the geophysical situations. Because of systematic misinterpretation due to non- adequateness of model and real situation the further development implies the parallel improvement of used water models and recalibration with in-situ data. The paper will present for selected test sites of the European coasts results of algorithm application. It will show the improvement of the estimated water constituents by using regional specific model parameter. Derived maps of chlorophyll like pigments, sediments and aerosol optical thickness ar presented.

  19. Development, analysis, and testing of robust nonlinear guidance algorithms for space applications

    NASA Astrophysics Data System (ADS)

    Wibben, Daniel R.

    This work focuses on the analysis and application of various nonlinear, autonomous guidance algorithms that utilize sliding mode control to guarantee system stability and robustness. While the basis for the algorithms has previously been proposed, past efforts barely scratched the surface of the theoretical details and implications of these algorithms. Of the three algorithms that are the subject of this research, two are directly derived from optimal control theory and augmented using sliding mode control. Analysis of the derivation of these algorithms has shown that they are two different representations of the same result, one of which uses a simple error state model (Delta r/Deltav) and the other uses definitions of the zero-effort miss and zero-effort velocity (ZEM/ZEV) values. By investigating the dynamics of the defined sliding surfaces and their impact on the overall system, many implications have been deduced regarding the behavior of these systems which are noted to feature time-varying sliding modes. A formal finite time stability analysis has also been performed to theoretically demonstrate that the algorithms globally stabilize the system in finite time in the presence of perturbations and unmodeled dynamics. The third algorithm that has been subject to analysis is derived from a direct application of higher-order sliding mode control and Lyapunov stability analysis without consideration of optimal control theory and has been named the Multiple Sliding Surface Guidance (MSSG). Via use of reinforcement learning methods an optimal set of gains has been found that make the guidance perform similarly to an open-loop optimal solution. Careful side-by-side inspection of the MSSG and Optimal Sliding Guidance (OSG) algorithms has shown some striking similarities. A detailed comparison of the algorithms has demonstrated that though they are nearly indistinguishable at first glance, there are some key differences between the two algorithms and they are indeed

  20. Development of Variational Guiding Center Algorithms for Parallel Calculations in Experimental Magnetic Equilibria

    SciTech Connect

    Ellison, C. Leland; Finn, J. M.; Qin, H.; Tang, William M.

    2014-10-01

    Structure-preserving algorithms obtained via discrete variational principles exhibit strong promise for the calculation of guiding center test particle trajectories. The non-canonical Hamiltonian structure of the guiding center equations forms a novel and challenging context for geometric integration. To demonstrate the practical relevance of these methods, a prototypical variational midpoint algorithm is applied to an experimental magnetic equilibrium. The stability characteristics, conservation properties, and implementation requirements associated with the variational algorithms are addressed. Furthermore, computational run time is reduced for large numbers of particles by parallelizing the calculation on GPU hardware.

  1. Development of an algorithm to meaningfully interpret patterns in street-level methane concentrations

    NASA Astrophysics Data System (ADS)

    von Fischer, Joseph; Salo, Jessica; Griebenow, Claire; Bischak, Linde; Cooley, Daniel; Ham, Jay; Schumacher, Russ

    2013-04-01

    Methane (CH4) is an important greenhouse gas that has 70x greater heat forcing per molecule than CO2 over its ~10 year atmospheric residence time. Given this short residence time, there has been a surge of interest in mitigating anthropogenic CH4 sources because they will have a more immediate effect on warming rates. Recent observations of CH4 concentrations around the city of Boston reveal that natural gas distribution systems can have a very large number of leaks. However, there are a number of conceptual and practical challenges associated with interpretation of CH4 data gathered by car at the street level. In this presentation, we detail our efforts to develop an "algorithm" or set of standard practices for interpreting these patterns based on our own findings. At the most basic, we have evaluated approaches for vehicle driving patterns and management of the raw data. We also identify techniques for evaluating data quality and discerning when elevated CH4 may be due to other vehicles (e.g., CNG-powered city buses). We then compare methods for identifying "peaks" in CH4 concentration, and we discuss several approaches for relating concentration, space and wind data to emission rates. Finally, we provide some considerations for how the data from individual peaks might be aggregated to larger spatial scales.

  2. Development and evaluation of a new contoured cushion system with an optimized normalization algorithm.

    PubMed

    Li, Sujiao; Zhang, Zhengxiang; Wang, Jue

    2014-01-01

    Prevention of pressure sores remains a significant problem confronting spinal cord injury patients and the elderly with limited mobility. One vital aspect of this subject concerns the development of cushions to decrease pressure ulcers for seated patients, particularly those bound by wheelchairs. Here, we present a novel cushion system that employs interface pressure distribution between the cushion and the buttocks to design custom contoured foam cushion. An optimized normalization algorithm was proposed, with which interface pressure distribution was transformed into the carving depth of foam cushions according to the biomechanical characteristics of the foam. The shape and pressure-relief performance of the custom contoured foam cushions was investigated. The outcomes showed that the contoured shape of personalized cushion matched the buttock contour very well. Moreover, the custom contoured cushion could alleviate pressure under buttocks and increase subjective comfort and stability significantly. Furthermore, the fabricating method not only decreased the unit production cost but also simplified the procedure for manufacturing. All in all, this prototype seat cushion would be an effective and economical way to prevent pressure ulcers. PMID:25227054

  3. Development and Implementation of Image-based Algorithms for Measurement of Deformations in Material Testing

    PubMed Central

    Barazzetti, Luigi; Scaioni, Marco

    2010-01-01

    This paper presents the development and implementation of three image-based methods used to detect and measure the displacements of a vast number of points in the case of laboratory testing on construction materials. Starting from the needs of structural engineers, three ad hoc tools for crack measurement in fibre-reinforced specimens and 2D or 3D deformation analysis through digital images were implemented and tested. These tools make use of advanced image processing algorithms and can integrate or even substitute some traditional sensors employed today in most laboratories. In addition, the automation provided by the implemented software, the limited cost of the instruments and the possibility to operate with an indefinite number of points offer new and more extensive analysis in the field of material testing. Several comparisons with other traditional sensors widely adopted inside most laboratories were carried out in order to demonstrate the accuracy of the implemented software. Implementation details, simulations and real applications are reported and discussed in this paper. PMID:22163612

  4. High-order derivative spectroscopy for selecting spectral regions and channels for remote sensing algorithm development

    NASA Astrophysics Data System (ADS)

    Bostater, Charles R., Jr.

    1999-12-01

    A remote sensing reflectance model, which describes the transfer of irradiant light within a plant canopy or water column has previously been used to simulate the nadir viewing reflectance of vegetation canopies and leaves under solar induced or an artificial light source and the water surface reflectance. Wavelength dependent features such as canopy reflectance leaf absorption and canopy bottom reflectance as well as water absorption and water bottom reflectance have been used to simulate or generate synthetic canopy and water surface reflectance signatures. This paper describes how derivative spectroscopy can be utilized to invert the synthetic or modeled as well as measured reflectance signatures with the goal of selecting the optimal spectral channels or regions of these environmental media. Specifically, in this paper synthetic and measured reflectance signatures are used for selecting vegetative dysfunction variables for different plant species. The measured reflectance signatures as well as model derived or synthetic signatures are processed using extremely fast higher order derivative processing techniques which filter the synthetic/modeled or measured spectra and automatically selects the optimal channels for automatic and direct algorithm application. The higher order derivative filtering technique makes use of a translating and dilating, derivative spectroscopy signal processing (TDDS-SPR) approach based upon remote sensing science and radiative transfer theory. Thus the technique described, unlike other signal processing techniques being developed for hyperspectral signatures and associated imagery, is based upon radiative transfer theory instead of statistical or purely mathematical operational techniques such as wavelets.

  5. Algorithm for Compressing Time-Series Data

    NASA Technical Reports Server (NTRS)

    Hawkins, S. Edward, III; Darlington, Edward Hugo

    2012-01-01

    An algorithm based on Chebyshev polynomials effects lossy compression of time-series data or other one-dimensional data streams (e.g., spectral data) that are arranged in blocks for sequential transmission. The algorithm was developed for use in transmitting data from spacecraft scientific instruments to Earth stations. In spite of its lossy nature, the algorithm preserves the information needed for scientific analysis. The algorithm is computationally simple, yet compresses data streams by factors much greater than two. The algorithm is not restricted to spacecraft or scientific uses: it is applicable to time-series data in general. The algorithm can also be applied to general multidimensional data that have been converted to time-series data, a typical example being image data acquired by raster scanning. However, unlike most prior image-data-compression algorithms, this algorithm neither depends on nor exploits the two-dimensional spatial correlations that are generally present in images. In order to understand the essence of this compression algorithm, it is necessary to understand that the net effect of this algorithm and the associated decompression algorithm is to approximate the original stream of data as a sequence of finite series of Chebyshev polynomials. For the purpose of this algorithm, a block of data or interval of time for which a Chebyshev polynomial series is fitted to the original data is denoted a fitting interval. Chebyshev approximation has two properties that make it particularly effective for compressing serial data streams with minimal loss of scientific information: The errors associated with a Chebyshev approximation are nearly uniformly distributed over the fitting interval (this is known in the art as the "equal error property"); and the maximum deviations of the fitted Chebyshev polynomial from the original data have the smallest possible values (this is known in the art as the "min-max property").

  6. Development of an algorithm to improve the accuracy of dose delivery in Gamma Knife radiosurgery

    NASA Astrophysics Data System (ADS)

    Cernica, George Dumitru

    2007-12-01

    Gamma Knife stereotactic radiosurgery has demonstrated decades of successful treatments. Despite its high spatial accuracy, the Gamma Knife's planning software, GammaPlan, uses a simple exponential as the TPR curve for all four collimator sizes, and a skull scaling device to acquire ruler measurements to interpolate a threedimensional spline to model the patient's skull. The consequences of these approximations have not been previously investigated. The true TPR curves of the four collimators were measured by blocking 200 of the 201 sources with steel plugs. Additional attenuation was provided through the use of a 16 cm tungsten sphere, designed to enable beamlet measurements along one axis. TPR, PDD, and beamlet profiles were obtained using both an ion chamber and GafChromic EBT film for all collimators. Additionally, an in-house planning algorithm able to calculate the contour of the skull directly from an image set and implement the measured beamlet data in shot time calculations was developed. Clinical and theoretical Gamma Knife cases were imported into our algorithm. The TPR curves showed small deviations from a simple exponential curve, with average discrepancies under 1%, but with a maximum discrepancy of 2% found for the 18 mm collimator beamlet at shallow depths. The consequences on the PDD of the of the beamlets were slight, with a maximum of 1.6% found with the 18 mm collimator beamlet. Beamlet profiles of the 4 mm, 8 mm, and 14 mm showed some underestimates of the off-axis ratio near the shoulders (up to 10%). The toes of the profiles were underestimated for all collimators, with differences up to 7%. Shot times were affected by up to 1.6% due to TPR differences, but clinical cases showed deviations by no more than 0.5%. The beamlet profiles affected the dose calculations more significantly, with shot time calculations differing by as much as 0.8%. The skull scaling affected the shot time calculations the most significantly, with differences of up to 5

  7. The Development of Several Electromagnetic Monitoring Strategies and Algorithms for Validating Pre-Earthquake Electromagnetic Signals

    NASA Astrophysics Data System (ADS)

    Bleier, T. E.; Dunson, J. C.; Roth, S.; Mueller, S.; Lindholm, C.; Heraud, J. A.

    2012-12-01

    QuakeFinder, a private research group in California, reports on the development of a 100+ station network consisting of 3-axis induction magnetometers, and air conductivity sensors to collect and characterize pre-seismic electromagnetic (EM) signals. These signals are combined with daily Infra Red signals collected from the GOES weather satellite infrared (IR) instrument to compare and correlate with the ground EM signals, both from actual earthquakes and boulder stressing experiments. This presentation describes the efforts QuakeFinder has undertaken to automatically detect these pulse patterns using their historical data as a reference, and to develop other discriminative algorithms that can be used with air conductivity sensors, and IR instruments from the GOES satellites. The overall big picture results of the QuakeFinder experiment are presented. In 2007, QuakeFinder discovered the occurrence of strong uni-polar pulses in their magnetometer coil data that increased in tempo dramatically prior to the M5.1 earthquake at Alum Rock, California. Suggestions that these pulses might have been lightning or power-line arcing did not fit with the data actually recorded as was reported in Bleier [2009]. Then a second earthquake occurred near the same site on January 7, 2010 as was reported in Dunson [2011], and the pattern of pulse count increases before the earthquake occurred similarly to the 2007 event. There were fewer pulses, and the magnitude of them was decreased, both consistent with the fact that the earthquake was smaller (M4.0 vs M5.4) and farther away (7Km vs 2km). At the same time similar effects were observed at the QuakeFinder Tacna, Peru site before the May 5th, 2010 M6.2 earthquake and a cluster of several M4-5 earthquakes.

  8. Development of effluent removal prediction model efficiency in septic sludge treatment plant through clonal selection algorithm.

    PubMed

    Ting, Sie Chun; Ismail, A R; Malek, M A

    2013-11-15

    This study aims at developing a novel effluent removal management tool for septic sludge treatment plants (SSTP) using a clonal selection algorithm (CSA). The proposed CSA articulates the idea of utilizing an artificial immune system (AIS) to identify the behaviour of the SSTP, that is, using a sequence batch reactor (SBR) technology for treatment processes. The novelty of this study is the development of a predictive SSTP model for effluent discharge adopting the human immune system. Septic sludge from the individual septic tanks and package plants will be desuldged and treated in SSTP before discharging the wastewater into a waterway. The Borneo Island of Sarawak is selected as the case study. Currently, there are only two SSTPs in Sarawak, namely the Matang SSTP and the Sibu SSTP, and they are both using SBR technology. Monthly effluent discharges from 2007 to 2011 in the Matang SSTP are used in this study. Cross-validation is performed using data from the Sibu SSTP from April 2011 to July 2012. Both chemical oxygen demand (COD) and total suspended solids (TSS) in the effluent were analysed in this study. The model was validated and tested before forecasting the future effluent performance. The CSA-based SSTP model was simulated using MATLAB 7.10. The root mean square error (RMSE), mean absolute percentage error (MAPE), and correction coefficient (R) were used as performance indexes. In this study, it was found that the proposed prediction model was successful up to 84 months for the COD and 109 months for the TSS. In conclusion, the proposed CSA-based SSTP prediction model is indeed beneficial as an engineering tool to forecast the long-run performance of the SSTP and in turn, prevents infringement of future environmental balance in other towns in Sarawak.

  9. Successive smoothing algorithm for constructing the semiempirical model developed at ONERA to predict unsteady aerodynamic forces. [aeroelasticity in helicopters

    NASA Technical Reports Server (NTRS)

    Petot, D.; Loiseau, H.

    1982-01-01

    Unsteady aerodynamic methods adopted for the study of aeroelasticity in helicopters are considered with focus on the development of a semiempirical model of unsteady aerodynamic forces acting on an oscillating profile at high incidence. The successive smoothing algorithm described leads to the model's coefficients in a very satisfactory manner.

  10. Detection of fruit-fly infestation in olives using X-ray imaging: Algorithm development and prospects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An algorithm using a Bayesian classifier was developed to automatically detect olive fruit fly infestations in x-ray images of olives. The data set consisted of 249 olives with various degrees of infestation and 161 non-infested olives. Each olive was x-rayed on film and digital images were acquired...

  11. A preliminary report on the development of MATLAB tensor classes for fast algorithm prototyping.

    SciTech Connect

    Bader, Brett William; Kolda, Tamara Gibson

    2004-07-01

    We describe three MATLAB classes for manipulating tensors in order to allow fast algorithm prototyping. A tensor is a multidimensional or N-way array. We present a tensor class for manipulating tensors which allows for tensor multiplication and 'matricization.' We have further added two classes for representing tensors in decomposed format: cp{_}tensor and tucker{_}tensor. We demonstrate the use of these classes by implementing several algorithms that have appeared in the literature.

  12. The development of algorithms for parallel knowledge discovery using graphics accelerators

    NASA Astrophysics Data System (ADS)

    Zieliński, Paweł; Mulawka, Jan

    2011-10-01

    The paper broaches topics of selected knowledge discovery algorithms. Different implementations have been verified on parallel platforms, including graphics accelerators using CUDA technology, multi-core microprocessors using OpenMP and many graphics accelerators. Results of investigations have been compared in terms of performance and scalability. Different types of data representation were also tested. The possibilities of both platforms, using the classification algorithms: the k-nearest neighbors, support vector machines and logistic regression are discussed.

  13. Timing of human preimplantation embryonic development is confounded by embryo origin

    PubMed Central

    Kirkegaard, K.; Sundvall, L.; Erlandsen, M.; Hindkjær, J.J.; Knudsen, U.B.; Ingerslev, H.J.

    2016-01-01

    STUDY QUESTION To what extent do patient- and treatment-related factors explain the variation in morphokinetic parameters proposed as embryo viability markers? SUMMARY ANSWER Up to 31% of the observed variation in timing of embryo development can be explained by embryo origin, but no single factor elicits a systematic influence. WHAT IS KNOWN ALREADY Several studies report that culture conditions, patient characteristics and treatment influence timing of embryo development, which have promoted the perception that each clinic must develop individual models. Most of the studies have, however, treated embryos from one patient as independent observations, and only very few studies that evaluate the influence from patient- and treatment-related factors on timing of development or time-lapse parameters as predictors of viability have controlled for confounding, which implies a high risk of overestimating the statistical significance of potential correlations. STUDY DESIGN, SIZE, DURATION Infertile patients were prospectively recruited to a cohort study at a hospital fertility clinic from February 2011 to May 2013. Patients aged <38 years without endometriosis were eligible if ≥8 oocytes were retrieved. Patients were included only once. All embryos were monitored for 6 days in a time-lapse incubator. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 1507 embryos from 243 patients were included. The influence of fertilization method, BMI, maternal age, FSH dose and number of previous cycles on timing of t2-t5, duration of the 2- and 3-cell stage, and development of a blastocoel (tEB) and full blastocoel (tFB) was tested in multivariate, multilevel linear regression analysis. Predictive parameters for live birth were tested in a logistic regression analysis for 223 single transferred blastocysts, where time-lapse parameters were investigated along with patient and embryo characteristics. MAIN RESULTS AND THE ROLE OF CHANCE Moderate intra-class correlation coefficients

  14. Analysis of Multivariate Experimental Data Using A Simplified Regression Model Search Algorithm

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert M.

    2013-01-01

    A new regression model search algorithm was developed that may be applied to both general multivariate experimental data sets and wind tunnel strain-gage balance calibration data. The algorithm is a simplified version of a more complex algorithm that was originally developed for the NASA Ames Balance Calibration Laboratory. The new algorithm performs regression model term reduction to prevent overfitting of data. It has the advantage that it needs only about one tenth of the original algorithm's CPU time for the completion of a regression model search. In addition, extensive testing showed that the prediction accuracy of math models obtained from the simplified algorithm is similar to the prediction accuracy of math models obtained from the original algorithm. The simplified algorithm, however, cannot guarantee that search constraints related to a set of statistical quality requirements are always satisfied in the optimized regression model. Therefore, the simplified algorithm is not intended to replace the original algorithm. Instead, it may be used to generate an alternate optimized regression model of experimental data whenever the application of the original search algorithm fails or requires too much CPU time. Data from a machine calibration of NASA's MK40 force balance is used to illustrate the application of the new search algorithm.

  15. Analysis of Multivariate Experimental Data Using A Simplified Regression Model Search Algorithm

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert Manfred

    2013-01-01

    A new regression model search algorithm was developed in 2011 that may be used to analyze both general multivariate experimental data sets and wind tunnel strain-gage balance calibration data. The new algorithm is a simplified version of a more complex search algorithm that was originally developed at the NASA Ames Balance Calibration Laboratory. The new algorithm has the advantage that it needs only about one tenth of the original algorithm's CPU time for the completion of a search. In addition, extensive testing showed that the prediction accuracy of math models obtained from the simplified algorithm is similar to the prediction accuracy of math models obtained from the original algorithm. The simplified algorithm, however, cannot guarantee that search constraints related to a set of statistical quality requirements are always satisfied in the optimized regression models. Therefore, the simplified search algorithm is not intended to replace the original search algorithm. Instead, it may be used to generate an alternate optimized regression model of experimental data whenever the application of the original search algorithm either fails or requires too much CPU time. Data from a machine calibration of NASA's MK40 force balance is used to illustrate the application of the new regression model search algorithm.

  16. Development of double-pair double difference earthquake location algorithm for improving earthquake locations

    NASA Astrophysics Data System (ADS)

    Guo, Hao; Zhang, Haijiang

    2016-10-01

    Event-pair double-difference (DD) earthquake location method, as incorporated in hypoDD, has been widely used to improve relative earthquake locations by using event-pair differential arrival times from pairs of events to common stations because some common path anomalies outside the source region can be canceled out due to similar ray paths. Similarly, station-pair differential arrival times from one event to pairs of stations can also be used to improve earthquake locations by canceling out the event origin time and some path anomalies inside the source region. To utilize advantages of both DD location methods, we have developed a new double-pair DD location method to use differential times constructed from pairs of events to pairs of stations to determine higher-precision relative earthquake locations. Compared to the event-pair and station-pair DD location methods, the new method can remove event origin times and station correction terms from the inversion system and cancel out path anomalies both outside and inside the source region at the same time. The new method is tested on earthquakes around the San Andreas Fault, California to validate its performance. From earthquake relocations it is demonstrated that the double-pair DD location method is able to better sharpen the images of seismicity with smaller relative location uncertainties compared to the event-pair DD location method and thus to reveal more fine-scale structures. In comparison, among three DD location methods, station-pair DD location method can better improve the absolute earthquake locations. For this reason, we further propose a new location strategy combining station-pair and double-pair differential times to determine accurate absolute and relative locations at the same time, which is validated by both synthetic and real datasets.

  17. Preliminary Development and Evaluation of Lightning Jump Algorithms for the Real-Time Detection of Severe Weather

    NASA Technical Reports Server (NTRS)

    Schultz, Christopher J.; Petersen, Walter A.; Carey, Lawrence D.

    2009-01-01

    Previous studies have demonstrated that rapid increases in total lightning activity (intracloud + cloud-to-ground) are often observed tens of minutes in advance of the occurrence of severe weather at the ground. These rapid increases in lightning activity have been termed "lightning jumps." Herein, we document a positive correlation between lightning jumps and the manifestation of severe weather in thunderstorms occurring across the Tennessee Valley and Washington D.C. A total of 107 thunderstorms were examined in this study, with 69 of the 107 thunderstorms falling into the category of non-severe, and 38 into the category of severe. From the dataset of 69 isolated non-severe thunderstorms, an average peak 1 minute flash rate of 10 flashes/min was determined. A variety of severe thunderstorm types were examined for this study including an MCS, MCV, tornadic outer rainbands of tropical remnants, supercells, and pulse severe thunderstorms. Of the 107 thunderstorms, 85 thunderstorms (47 non-severe, 38 severe) from the Tennessee Valley and Washington D.C tested 6 lightning jump algorithm configurations (Gatlin, Gatlin 45, 2(sigma), 3(sigma), Threshold 10, and Threshold 8). Performance metrics for each algorithm were then calculated, yielding encouraging results from the limited sample of 85 thunderstorms. The 2(sigma) lightning jump algorithm had a high probability of detection (POD; 87%), a modest false alarm rate (FAR; 33%), and a solid Heidke Skill Score (HSS; 0.75). A second and more simplistic lightning jump algorithm named the Threshold 8 lightning jump algorithm also shows promise, with a POD of 81% and a FAR of 41%. Average lead times to severe weather occurrence for these two algorithms were 23 minutes and 20 minutes, respectively. The overall goal of this study is to advance the development of an operationally-applicable jump algorithm that can be used with either total lightning observations made from the ground, or in the near future from space using the

  18. End-to-End Design, Development and Testing of GOES-R Level 1 and 2 Algorithms

    NASA Astrophysics Data System (ADS)

    Zaccheo, T.; Copeland, A.; Steinfelt, E.; Van Rompay, P.; Werbos, A.

    2012-12-01

    GOES-R is the next generation of the National Oceanic and Atmospheric Administration's (NOAA) Geostationary Operational Environmental Satellite (GOES) System, and it represents a new technological era in operational geostationary environmental satellite systems. GOES-R will provide advanced products, based on government-supplied algorithms, which describe the state of the atmosphere, land, and oceans over the Western Hemisphere. The Harris GOES-R Core Ground Segment (GS) Team will provide the ground processing software and infrastructure needed to produce and distribute these data products. As part of this effort, new or updated Level 1b and Level 2+ algorithms will be deployed in the GOES-R Product Generation (PG) Element. In this work, we describe the general approach currently being employed to migrate these Level 1b (L1b) and Level 2+ (L2+) GOES-R PG algorithms from government-provided scientific descriptions to their implementation as integrated software, and provide an overview of how Product Generation software works with the other elements of the Ground Segment to produce Level 1/Level 2+ end-products. In general, GOES-R L1b algorithms ingest reformatted raw sensor data and ancillary information to produce geo-located GOES-R L1b data, and GOES-R L2+ algorithms ingest L1b data and other ancillary/auxiliary/intermediate information to produce L2+ products such as aerosol optical depth, rainfall rate, derived motion winds, and snow cover. In this presentation we provide an overview of the Algorithm development life cycle, the common Product Generation software architecture, and the common test strategies used to verify/validate the scientific implementation. This work will highlight the Software Integration and Test phase of the software life-cycle and the suite of automated test/analysis tools developed to insure the implemented algorithms meet desired reproducibility. As part of this discussion we will summarize the results of our algorithm testing to date

  19. Characterizing the Preturbulence Environment for Sensor Development, New Hazard Algorithms and NASA Experimental Flight Planning

    NASA Technical Reports Server (NTRS)

    Kaplan, Michael L.; Lin, Yuh-Lang

    2004-01-01

    During the grant period, several tasks were performed in support of the NASA Turbulence Prediction and Warning Systems (TPAWS) program. The primary focus of the research was on characterizing the preturbulence environment by developing predictive tools and simulating atmospheric conditions that preceded severe turbulence. The goal of the research being to provide both dynamical understanding of conditions that preceded turbulence as well as providing predictive tools in support of operational NASA B-757 turbulence research flights. The advancements in characterizing the preturbulence environment will be applied by NASA to sensor development for predicting turbulence onboard commercial aircraft. Numerical simulations with atmospheric models as well as multi-scale observational analyses provided insights into the environment organizing turbulence in a total of forty-eight specific case studies of severe accident producing turbulence on commercial aircraft. These accidents exclusively affected commercial aircraft. A paradigm was developed which diagnosed specific atmospheric circulation systems from the synoptic scale down to the meso-y scale that preceded turbulence in both clear air and in proximity to convection. The emphasis was primarily on convective turbulence as that is what the TPAWS program is most focused on in terms of developing improved sensors for turbulence warning and avoidance. However, the dynamical paradigm also has applicability to clear air and mountain turbulence. This dynamical sequence of events was then employed to formulate and test new hazard prediction indices that were first tested in research simulation studies and then ultimately were further tested in support of the NASA B-757 turbulence research flights. The new hazard characterization algorithms were utilized in a Real Time Turbulence Model (RTTM) that was operationally employed to support the NASA B-757 turbulence research flights. Improvements in the RTTM were implemented in an

  20. Planning fuel-conservative descents in an airline environmental using a small programmable calculator: Algorithm development and flight test results

    NASA Technical Reports Server (NTRS)

    Knox, C. E.; Vicroy, D. D.; Simmon, D. A.

    1985-01-01

    A simple, airborne, flight-management descent algorithm was developed and programmed into a small programmable calculator. The algorithm may be operated in either a time mode or speed mode. The time mode was designed to aid the pilot in planning and executing a fuel-conservative descent to arrive at a metering fix at a time designated by the air traffic control system. The speed model was designed for planning fuel-conservative descents when time is not a consideration. The descent path for both modes was calculated for a constant with considerations given for the descent Mach/airspeed schedule, gross weight, wind, wind gradient, and nonstandard temperature effects. Flight tests, using the algorithm on the programmable calculator, showed that the open-loop guidance could be useful to airline flight crews for planning and executing fuel-conservative descents.

  1. Planning fuel-conservative descents in an airline environmental using a small programmable calculator: algorithm development and flight test results

    SciTech Connect

    Knox, C.E.; Vicroy, D.D.; Simmon, D.A.

    1985-05-01

    A simple, airborne, flight-management descent algorithm was developed and programmed into a small programmable calculator. The algorithm may be operated in either a time mode or speed mode. The time mode was designed to aid the pilot in planning and executing a fuel-conservative descent to arrive at a metering fix at a time designated by the air traffic control system. The speed model was designed for planning fuel-conservative descents when time is not a consideration. The descent path for both modes was calculated for a constant with considerations given for the descent Mach/airspeed schedule, gross weight, wind, wind gradient, and nonstandard temperature effects. Flight tests, using the algorithm on the programmable calculator, showed that the open-loop guidance could be useful to airline flight crews for planning and executing fuel-conservative descents.

  2. Development of a dose algorithm for the modified panasonic UD-802 personal dosimeter used at three mile island

    SciTech Connect

    Miklos, J. A.; Plato, P.

    1988-01-01

    During the fall of 1981, the personnel dosimetry group at GPU Nuclear Corporation at Three Mile Island (TMI) requested assistance from The University of Michigan (UM) in developing a dose algorithm for use at TMI-2. The dose algorithm had to satisfy the specific needs of TMI-2, particularly the need to distinguish beta-particle emitters of different energies, as well as having the capability of satisfying the requirements of the American National Standards Institute (ANSI) N13.11-1983 standard. A standard Panasonic UD-802 dosimeter was modified by having the plastic filter over element 2 removed. The dosimeter and hanger consists of the elements with a 14 mg/cm/sup 2/ density thickness and the filtrations shown. The hanger on this dosimeter had a double open window to facilitate monitoring for low-energy beta particles. The dose algorithm was written to satisfy the requirements of the ANSI N13.11-1983 standard, to include /sup 204/Tl with mixtures of /sup 204/Tl with /sup 90/Sr//sup 90/Y and /sup 137/Cs, and to include 81- and 200-keV average energy X-ray spectra. Stress tests were conducted to observe the algorithm performance to low doses, temperature, humidity, and the residual response following high-dose irradiations. The ability of the algorithm to determine dose from the beta particles of /sup 147/Pm was also investigated.

  3. Development of a blended-control, predictor-corrector guidance algorithm for a crewed Mars aerocapture vehicle

    NASA Astrophysics Data System (ADS)

    Jits, Roman Yuryevich

    A robust blended-control guidance system for a crewed Mars aerocapture vehicle is developed. The key features of its guidance algorithm are the use of the both bank-angle and angle-of-attack modulation to control the aerobraking vehicle, and the use of multiple controls (sequenced pairs of bank-angles and angles-of-attack) within its numeric predictor-corrector targeting routine. The guidance algorithm macrologic is based on extensive open loop trajectory analyses, described in the present research, which led to the selection of a blended-control scheme. A heuristic approach to recover from situations where no converged guidance solution could be found by the numeric predictor-corrector is implemented in the guidance algorithm, and has been successfully demonstrated in a large number of test runs. In this research both the outer and inner loop of the guidance and control system employ the POST (Program to Optimize Simulated Trajectories) computer code as the basic simulation module. At each guidance update, the inner loop solves the rigorous three-dimensional equations of motion and computes the control (bank-angle and angle-of-attack) sequence that is required to meet the required atmospheric exit conditions. Throughout the aerocapture trajectory, the guidance algorithm modifies this control sequence computed by the inner loop, and generates commanded controls for the vehicle, which, when implemented by the outer loop, meet an imposed g-load constraint of 5 Earth g's and compensate for unexpected off-nominal conditions. This blended-control, predictor-corrector guidance algorithm has been successfully developed, implemented and tested and has been shown to be capable of meeting the prescribed g-load constraint and guiding the vehicle to the desired exit conditions for a range of off-nominal factors much wider than those which could be accommodated by prior algorithms and bank-angle-only guidance.

  4. A VLSI architecture for simplified arithmetic Fourier transform algorithm

    NASA Technical Reports Server (NTRS)

    Reed, Irving S.; Shih, Ming-Tang; Truong, T. K.; Hendon, E.; Tufts, D. W.

    1992-01-01

    The arithmetic Fourier transform (AFT) is a number-theoretic approach to Fourier analysis which has been shown to perform competitively with the classical FFT in terms of accuracy, complexity, and speed. Theorems developed in a previous paper for the AFT algorithm are used here to derive the original AFT algorithm which Bruns found in 1903. This is shown to yield an algorithm of less complexity and of improved performance over certain recent AFT algorithms. A VLSI architecture is suggested for this simplified AFT algorithm. This architecture uses a butterfly structure which reduces the number of additions by 25 percent of that used in the direct method.

  5. Diagnosis and treatment of acute ankle injuries: development of an evidence-based algorithm

    PubMed Central

    Polzer, Hans; Kanz, Karl Georg; Prall, Wolf Christian; Haasters, Florian; Ockert, Ben; Mutschler, Wolf; Grote, Stefan

    2011-01-01

    Acute ankle injuries are among the most common injuries in emergency departments. However, there are still no standardized examination procedures or evidence-based treatment. Therefore, the aim of this study was to systematically search the current literature, classify the evidence, and develop an algorithm for the diagnosis and treatment of acute ankle injuries. We systematically searched PubMed and the Cochrane Database for randomized controlled trials, meta-analyses, systematic reviews or, if applicable, observational studies and classified them according to their level of evidence. According to the currently available literature, the following recommendations have been formulated: i) the Ottawa Ankle/Foot Rule should be applied in order to rule out fractures; ii) physical examination is sufficient for diagnosing injuries to the lateral ligament complex; iii) classification into stable and unstable injuries is applicable and of clinical importance; iv) the squeeze-, crossed leg- and external rotation test are indicative for injuries of the syndesmosis; v) magnetic resonance imaging is recommended to verify injuries of the syndesmosis; vi) stable ankle sprains have a good prognosis while for unstable ankle sprains, conservative treatment is at least as effective as operative treatment without the related possible complications; vii) early functional treatment leads to the fastest recovery and the least rate of reinjury; viii) supervised rehabilitation reduces residual symptoms and re-injuries. Taken these recommendations into account, we present an applicable and evidence-based, step by step, decision pathway for the diagnosis and treatment of acute ankle injuries, which can be implemented in any emergency department or doctor's practice. It provides quality assurance for the patient and promotes confidence in the attending physician. PMID:22577506

  6. The Centennial of Counselor Education: Origin and Early Development of a Discipline

    ERIC Educational Resources Information Center

    Savickas, Mark L.

    2011-01-01

    July 7, 2011, marks the centennial of counselor education as a formal discipline. In recognition of its 100th birthday, the author of this article describes the origins of the discipline, beginning with its prehistory in the work of Frank Parsons to establish the practice of vocational guidance, describing the 1st course in counselor education at…

  7. Development of an Algorithm for MODIS and VIIRS Cloud Optical Property Data Record Continuity

    NASA Astrophysics Data System (ADS)

    Meyer, K.; Platnick, S. E.; Ackerman, S. A.; Heidinger, A. K.; Holz, R.; Wind, G.; Amarasinghe, N.; Marchant, B.

    2015-12-01

    The launch of Suomi NPP in the fall of 2011 began the next generation of U.S. operational polar orbiting environmental observations. Similar to MODIS, the VIIRS imager provides visible through IR observations at moderate spatial resolution with a 1330 LT equatorial crossing consistent with MODIS on the Aqua platform. However, unlike MODIS, VIIRS lacks key water vapor and CO2 absorbing channels used by the MODIS cloud algorithms for high cloud detection and cloud-top property retrievals. In addition, there is a significant change in the spectral location of the 2.1μm shortwave-infrared channel used by MODIS for cloud optical/microphysical retrievals. Given the instrument differences between MODIS EOS and VIIRS S-NPP/JPSS, we discuss our adopted method for merging the 15+ year MODIS observational record with VIIRS in order to generate cloud optical property data record continuity across the observing systems. The optical property retrieval code uses heritage algorithms that produce the existing MODIS cloud optical and microphysical properties product (MOD06). As explained in other presentations submitted to this session, the NOAA AWG/CLAVR-x cloud-top property algorithm and a common MODIS-VIIRS cloud mask feed into the optical property algorithm to account for the different channel sets of the two imagers. Data granule and aggregated examples for the current version of the algorithm will be shown.

  8. Algorithm and code development for unsteady three-dimensional Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Obayashi, Shigeru

    1991-01-01

    A streamwise upwind algorithm for solving the unsteady 3-D Navier-Stokes equations was extended to handle the moving grid system. It is noted that the finite volume concept is essential to extend the algorithm. The resulting algorithm is conservative for any motion of the coordinate system. Two extensions to an implicit method were considered and the implicit extension that makes the algorithm computationally efficient is implemented into Ames's aeroelasticity code, ENSAERO. The new flow solver has been validated through the solution of test problems. Test cases include three-dimensional problems with fixed and moving grids. The first test case shown is an unsteady viscous flow over an F-5 wing, while the second test considers the motion of the leading edge vortex as well as the motion of the shock wave for a clipped delta wing. The resulting algorithm has been implemented into ENSAERO. The upwind version leads to higher accuracy in both steady and unsteady computations than the previously used central-difference method does, while the increase in the computational time is small.

  9. Towards developing robust algorithms for solving partial differential equations on MIMD machines

    NASA Technical Reports Server (NTRS)

    Saltz, J. H.; Naik, V. K.

    1985-01-01

    Methods for efficient computation of numerical algorithms on a wide variety of MIMD machines are proposed. These techniques reorganize the data dependency patterns to improve the processor utilization. The model problem finds the time-accurate solution to a parabolic partial differential equation discretized in space and implicitly marched forward in time. The algorithms are extensions of Jacobi and SOR. The extensions consist of iterating over a window of several timesteps, allowing efficient overlap of computation with communication. The methods increase the degree to which work can be performed while data are communicated between processors. The effect of the window size and of domain partitioning on the system performance is examined both by implementing the algorithm on a simulated multiprocessor system.

  10. Towards developing robust algorithms for solving partial differential equations on MIMD machines

    NASA Technical Reports Server (NTRS)

    Saltz, Joel H.; Naik, Vijay K.

    1988-01-01

    Methods for efficient computation of numerical algorithms on a wide variety of MIMD machines are proposed. These techniques reorganize the data dependency patterns to improve the processor utilization. The model problem finds the time-accurate solution to a parabolic partial differential equation discretized in space and implicitly marched forward in time. The algorithms are extensions of Jacobi and SOR. The extensions consist of iterating over a window of several timesteps, allowing efficient overlap of computation with communication. The methods increase the degree to which work can be performed while data are communicated between processors. The effect of the window size and of domain partitioning on the system performance is examined both by implementing the algorithm on a simulated multiprocessor system.

  11. CoSMIR Measurements in Support of GPM Algorithm Development and Validation

    NASA Astrophysics Data System (ADS)

    Skofronick Jackson, G.; Wang, J. R.

    2012-12-01

    The Conical Scanning Millimeter-wave Imaging Radiometer (CoSMIR) is an aircraft instrument flown to reduce assumptions in GPM (Global Precipitation Measurement) satellite retrieval algorithms and to provide validation data. This instrument plays the role of an airborne high-frequency simulator for the GPM mission's Microwave Imager (GMI) and has channels particularly sensitive to precipitating ice and snow in clouds. CoSMIR flew on the ER-2 in the Midlatitude Continental Convective Cloud Experiment (MC3E) field campaign in Oklahoma during April-June 2011 and on the DC-8 for the GPM Cold-season Precipitation Experiment (GCPEx) in January-February 2012 in Ontario, Canada. A unique feature of CoSMIR is that it is programmed to acquire radiometric measurements in both conical and cross-track scans nearly simultaneously. An advantage of this dual scanning is that it allows comparison/validation with satellite measurements in conical modes (e.g., TRMM, SSMIS) and cross-track modes (e.g., ATMS, MHS). The GPM Microwave Imager (GMI), scheduled for launch in early 2014, includes 13 channels ranging from 10 to 183±7 GHz. Precipitation retrievals over land with a microwave imager such as the Tropical Rainfall Measurement Mission (TRMM) Microwave Imager (TMI) often face difficulties in measuring precipitation because of the lack of surface radiometric contrast and homogeneity. GMI with additional high frequency channels, beyond those of TMI, should improve the retrieval skill over land surface. Furthermore, GMI could expand the global precipitation retrievals to include frozen hydrometeors such as graupel above the melting layer all the way to snow falling at the Earth's surface. To explore these opportunities and acquire data for algorithm development, CoSMIR has six channels that precisely match GMI high frequency channels with the following: 89 (dual-polarized), 165 (dual-polarized), 183.3±1, 183.3±3, and 183.3±7 GHz. During the MC3E field campaign, CoSMIR was on the ER

  12. THE DEVELOPMENT OF A PARAMETERIZED SCATTER REMOVAL ALGORITHM FOR NUCLEAR MATERIALS IDENTIFICATION SYSTEM IMAGING

    SciTech Connect

    Grogan, Brandon R

    2010-05-01

    This report presents a novel method for removing scattering effects from Nuclear Materials Identification System (NMIS) imaging. The NMIS uses fast neutron radiography to generate images of the internal structure of objects nonintrusively. If the correct attenuation through the object is measured, the positions and macroscopic cross sections of features inside the object can be determined. The cross sections can then be used to identify the materials, and a 3D map of the interior of the object can be reconstructed. Unfortunately, the measured attenuation values are always too low because scattered neutrons contribute to the unattenuated neutron signal. Previous efforts to remove the scatter from NMIS imaging have focused on minimizing the fraction of scattered neutrons that are misidentified as directly transmitted by electronically collimating and time tagging the source neutrons. The parameterized scatter removal algorithm (PSRA) approaches the problem from an entirely new direction by using Monte Carlo simulations to estimate the point scatter functions (PScFs) produced by neutrons scattering in the object. PScFs have been used to remove scattering successfully in other applications, but only with simple 2D detector models. This work represents the first time PScFs have ever been applied to an imaging detector geometry as complicated as the NMIS. By fitting the PScFs using a Gaussian function, they can be parameterized, and the proper scatter for a given problem can be removed without the need for rerunning the simulations each time. In order to model the PScFs, an entirely new method for simulating NMIS measurements was developed for this work. The development of the new models and the codes required to simulate them are presented in detail. The PSRA was used on several simulated and experimental measurements, and chi-squared goodness of fit tests were used to compare the corrected values to the ideal values that would be expected with no scattering. Using the

  13. The Development of a Parameterized Scatter Removal Algorithm for Nuclear Materials Identification System Imaging

    SciTech Connect

    Grogan, Brandon Robert

    2010-03-01

    This dissertation presents a novel method for removing scattering effects from Nuclear Materials Identification System (NMIS) imaging. The NMIS uses fast neutron radiography to generate images of the internal structure of objects non-intrusively. If the correct attenuation through the object is measured, the positions and macroscopic cross-sections of features inside the object can be determined. The cross sections can then be used to identify the materials and a 3D map of the interior of the object can be reconstructed. Unfortunately, the measured attenuation values are always too low because scattered neutrons contribute to the unattenuated neutron signal. Previous efforts to remove the scatter from NMIS imaging have focused on minimizing the fraction of scattered neutrons which are misidentified as directly transmitted by electronically collimating and time tagging the source neutrons. The parameterized scatter removal algorithm (PSRA) approaches the problem from an entirely new direction by using Monte Carlo simulations to estimate the point scatter functions (PScFs) produced by neutrons scattering in the object. PScFs have been used to remove scattering successfully in other applications, but only with simple 2D detector models. This work represents the first time PScFs have ever been applied to an imaging detector geometry as complicated as the NMIS. By fitting the PScFs using a Gaussian function, they can be parameterized and the proper scatter for a given problem can be removed without the need for rerunning the simulations each time. In order to model the PScFs, an entirely new method for simulating NMIS measurements was developed for this work. The development of the new models and the codes required to simulate them are presented in detail. The PSRA was used on several simulated and experimental measurements and chi-squared goodness of fit tests were used to compare the corrected values to the ideal values that would be expected with no scattering. Using

  14. Development of a Near Real-Time Hail Damage Swath Identification Algorithm for Vegetation

    NASA Technical Reports Server (NTRS)

    Bell, Jordan R.; Molthan, Andrew L.; Schultz, Kori A.; McGrath, Kevin M.; Burks, Jason E.

    2015-01-01

    Every year in the Midwest and Great Plains, widespread greenness forms in conjunction with the latter part of the spring-summer growing season. This prevalent greenness forms as a result of the high concentration of agricultural areas having their crops reach their maturity before the fall harvest. This time of year also coincides with an enhanced hail frequency for the Great Plains (Cintineo et al. 2012). These severe thunderstorms can bring damaging winds and large hail that can result in damage to the surface vegetation. The spatial extent of the damage can relatively small concentrated area or be a vast swath of damage that is visible from space. These large areas of damage have been well documented over the years. In the late 1960s aerial photography was used to evaluate crop damage caused by hail. As satellite remote sensing technology has evolved, the identification of these hail damage streaks has increased. Satellites have made it possible to view these streaks in additional spectrums. Parker et al. (2005) documented two streaks using the Moderate Resolution Imaging Spectroradiometer (MODIS) that occurred in South Dakota. He noted the potential impact that these streaks had on the surface temperature and associated surface fluxes that are impacted by a change in temperature. Gallo et al. (2012) examined at the correlation between radar signatures and ground observations from storms that produced a hail damage swath in Central Iowa also using MODIS. Finally, Molthan et al. (2013) identified hail damage streaks through MODIS, Landsat-7, and SPOT observations of different resolutions for the development of a potential near-real time applications. The manual analysis of hail damage streaks in satellite imagery is both tedious and time consuming, and may be inconsistent from event to event. This study focuses on development of an objective and automatic algorithm to detect these areas of damage in a more efficient and timely manner. This study utilizes the

  15. The development of a bearing spectral analyzer and algorithms to detect turbopump bearing wear from deflectometer and strain gage data

    NASA Astrophysics Data System (ADS)

    Martinez, Carol L.

    1992-07-01

    Over the last several years, Rocketdyne has actively developed condition and health monitoring techniques and their elements for rocket engine components, specifically high pressure turbopumps. Of key interest is the development of bearing signature analysis systems for real-time monitoring of the cryogen-cooled turbopump shaft bearings, which spin at speeds up to 36,000 RPM. These system elements include advanced bearing vibration sensors, signal processing techniques, wear mode algorithms, and integrated control software. Results of development efforts in the areas of signal processing and wear mode identification and quantification algorithms based on strain gage and deflectometer data are presented. Wear modes investigated include: inner race wear, cage pocket wear, outer race wear, differential ball wear, cracked inner race, and nominal wear.

  16. Development and validation of a linear recursive "Order- N" algorithm for the simulation of flexible space manipulator dynamics

    NASA Astrophysics Data System (ADS)

    Van Woerkom, P. Th. L. M.; de Boer, A.

    1995-01-01

    Robotic manipulators designed to operate on-board spacecraft and Space Stations are characterized by large spatial dimensions. The structural flexibility inherent in such manipulators introduces a noticeable and undesirable modification of the traditional rigid-body manipulator dynamics. As a result, the dynamics of the complete system comprising a flexible spacecraft or Space Station as a manipulator base, and an attached flexible manipulator, are also modified. Operational requirements related to high manoeuvre accuracy and modest manoeuvre duration, create the need for careful modelling and simulation of the dynamics of such systems. The objective of this paper is to outline the development and validation of an advanced algorithm for the simulation of the dynamics of such flexible spacecraft/space manipulator systems. The requirements imposed during the development of the present prototype dynamics simulator led to the modification and implementation of an existing linear recursive algorithm ("Order- N" algorithm), which requires a computational effort proportional to the number of component bodies in the system. Starting with the Lagrange form of the d'Alembert principle, we first deduce a parametric form which is found to yield—amongst others—the basic forms of the Newton-Euler, the d'Alembert and the Gauss dynamics principles. It is then shown how the application of each of the latter three principles can be made to lead graciously to the desired Order- N algorithm for the flexible multi-body system. The Order- N algorithm thus obtained and validated analytically, forms the basis for the prototype simulator REALDYN, designed to permit numerical simulation of the algorithm on UNIX workstations. Verification, numerical integration and further validation tests have been carried out. Some of the results obtained during the validation exercises could not be explained readily, even in the case of simple multi-body systems. The use of test tools and physical

  17. Bayesian Smoothing Algorithms in Partially Observed Markov Chains

    NASA Astrophysics Data System (ADS)

    Ait-el-Fquih, Boujemaa; Desbouvries, François

    2006-11-01

    Let x = {xn}n∈N be a hidden process, y = {yn}n∈N an observed process and r = {rn}n∈N some auxiliary process. We assume that t = {tn}n∈N with tn = (xn, rn, yn-1) is a (Triplet) Markov Chain (TMC). TMC are more general than Hidden Markov Chains (HMC) and yet enable the development of efficient restoration and parameter estimation algorithms. This paper is devoted to Bayesian smoothing algorithms for TMC. We first propose twelve algorithms for general TMC. In the Gaussian case, these smoothers reduce to a set of algorithms which include, among other solutions, extensions to TMC of classical Kalman-like smoothing algorithms (originally designed for HMC) such as the RTS algorithms, the Two-Filter algorithms or the Bryson and Frazier algorithm.

  18. Development of an algorithm to measure defect geometry using a 3D laser scanner

    NASA Astrophysics Data System (ADS)

    Kilambi, S.; Tipton, S. M.

    2012-08-01

    Current fatigue life prediction models for coiled tubing (CT) require accurate measurements of the defect geometry. Three-dimensional (3D) laser imaging has shown promise toward becoming a nondestructive, non-contacting method of surface defect characterization. Laser imaging provides a detailed photographic image of a flaw, in addition to a detailed 3D surface map from which its critical dimensions can be measured. This paper describes algorithms to determine defect characteristics, specifically depth, width, length and projected cross-sectional area. Curve-fitting methods were compared and implicit algebraic fits have higher probability of convergence compared to explicit geometric fits. Among the algebraic fits, the Taubin circle fit has the least error. The algorithm was able to extract the dimensions of the flaw geometry from the scanned data of CT to within a tolerance of about 0.127 mm, close to the tolerance specified for the laser scanner itself, compared to measurements made using traveling microscopes. The algorithm computes the projected surface area of the flaw, which could previously only be estimated from the dimension measurements and the assumptions made about cutter shape. Although shadows compromised the accuracy of the shape characterization, especially for deep and narrow flaws, the results indicate that the algorithm with laser scanner can be used for non-destructive evaluation of CT in the oil field industry. Further work is needed to improve accuracy, to eliminate shadow effects and to reduce radial deviation.

  19. Developments of aerosol retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS) and the retrieval accuracy test

    NASA Astrophysics Data System (ADS)

    KIM, M.; Kim, J.; Jeong, U.; Ahn, C.; Bhartia, P. K.; Torres, O.

    2013-12-01

    A scanning UV-Visible spectrometer, the GEMS (Geostationary Environment Monitoring Spectrometer) onboard the GEO-KOMPSAT2B (Geostationary Korea Multi-Purpose Satellite) is planned to be launched in geostationary orbit in 2018. The GEMS employs hyper-spectral imaging with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between aerosol absorption and molecular scattering can be advantageous in retrieving aerosol optical properties such as aerosol optical depth (AOD) and single scattering albedo (SSA). By taking the advantage, the OMI UV aerosol algorithm has provided information on the absorbing aerosol (Torres et al., 2007; Ahn et al., 2008). This study presents a UV-VIS algorithm to retrieve AOD and SSA from GEMS. The algorithm is based on the general inversion method, which uses pre-calculated look-up table with assumed aerosol properties and measurement condition. To obtain the retrieval accuracy, the error of the look-up table method occurred by the interpolation of pre-calculated radiances is estimated by using the reference dataset, and the uncertainties about aerosol type and height are evaluated. Also, the GEMS aerosol algorithm is tested with measured normalized radiance from OMI, a provisional data set for GEMS measurement, and the results are compared with the values from AERONET measurements over Asia. Additionally, the method for simultaneous retrieve of the AOD and aerosol height is discussed.

  20. Development of aerosol retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS)

    NASA Astrophysics Data System (ADS)

    Kim, Mijin; Kim, Jhoon; Park, Sang Seo; Jeong, Ukkyo; Ahn, Changwoo; Bhartia, Pawan. K.; Torres, Omar; Song, Chang-Keun; Han, Jin-Seok

    2014-05-01

    A scanning UV-Visible spectrometer, the GEMS (Geostationary Environment Monitoring Spectrometer) onboard the GEO-KOMPSAT2B (Geostationary Korea Multi-Purpose Satellite) is planned to be launched in geostationary orbit in 2018. The GEMS employs hyper-spectral imaging with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between aerosol absorption and molecular scattering can be advantageous in retrieving aerosol optical properties such as aerosol optical depth (AOD) and single scattering albedo (SSA). This study presents a UV-VIS algorithm to retrieve AOD and SSA from GEMS. The algorithm is based on the general inversion method, which uses pre-calculated look-up table (LUT) with assumed aerosol properties and measurement condition. To calculate LUT, aerosol optical properties over Asia [70°E-145°E, 0°N-50°N] are obtained from AERONET inversion data (level 2.0) at 46 AERONET sites, and are applied to VLIDORT (spur, 2006). Because the backscattering radiance in UV-Visible range has significant sensitivity to radiance absorptivity and size distribution of loading aerosol, aerosol types are classified from AERONET inversion data by using aerosol classification method suggested in Lee et al. (2010). Then the LUTs are calculated with average optical properties for each aerosol type. The GEMS aerosol algorithm is tested with OMI level-1B dataset, a provisional data for GEMS measurement. The aerosol types for each measured scene are selected by using both of UVAI and VISAI, and AOD and SSA are simultaneously retrieved by comparing simulated radiance with selected aerosol type and the measured value. The AOD and SSA retrieved from GEMS aerosol algorithm are well matched with OMI products, although the retrieved AOD is slightly higher than OMI value. To detect cloud pixel, spatial standard deviation test of radiance is applied in the

  1. Structured interview for mild traumatic brain injury after military blast: inter-rater agreement and development of diagnostic algorithm.

    PubMed

    Walker, William C; Cifu, David X; Hudak, Anne M; Goldberg, Gary; Kunz, Richard D; Sima, Adam P

    2015-04-01

    The existing gold standard for diagnosing a suspected previous mild traumatic brain injury (mTBI) is clinical interview. But it is prone to bias, especially for parsing the physical versus psychological effects of traumatic combat events, and its inter-rater reliability is unknown. Several standardized TBI interview instruments have been developed for research use but have similar limitations. Therefore, we developed the Virginia Commonwealth University (VCU) retrospective concussion diagnostic interview, blast version (VCU rCDI-B), and undertook this cross-sectional study aiming to 1) measure agreement among clinicians' mTBI diagnosis ratings, 2) using clinician consensus develop a fully structured diagnostic algorithm, and 3) assess accuracy of this algorithm in a separate sample. Two samples (n = 66; n = 37) of individuals within 2 years of experiencing blast effects during military deployment underwent semistructured interview regarding their worst blast experience. Five highly trained TBI physicians independently reviewed and interpreted the interview content and gave blinded ratings of whether or not the experience was probably an mTBI. Paired inter-rater reliability was extremely variable, with kappa ranging from 0.194 to 0.825. In sample 1, the physician consensus prevalence of probable mTBI was 84%. Using these diagnosis ratings, an algorithm was developed and refined from the fully structured portion of the VCU rCDI-B. The final algorithm considered certain symptom patterns more specific for mTBI than others. For example, an isolated symptom of "saw stars" was deemed sufficient to indicate mTBI, whereas an isolated symptom of "dazed" was not. The accuracy of this algorithm, when applied against the actual physician consensus in sample 2, was almost perfect (correctly classified = 97%; Cohen's kappa = 0.91). In conclusion, we found that highly trained clinicians often disagree on historical blast-related mTBI determinations. A fully structured interview

  2. Structured interview for mild traumatic brain injury after military blast: inter-rater agreement and development of diagnostic algorithm.

    PubMed

    Walker, William C; Cifu, David X; Hudak, Anne M; Goldberg, Gary; Kunz, Richard D; Sima, Adam P

    2015-04-01

    The existing gold standard for diagnosing a suspected previous mild traumatic brain injury (mTBI) is clinical interview. But it is prone to bias, especially for parsing the physical versus psychological effects of traumatic combat events, and its inter-rater reliability is unknown. Several standardized TBI interview instruments have been developed for research use but have similar limitations. Therefore, we developed the Virginia Commonwealth University (VCU) retrospective concussion diagnostic interview, blast version (VCU rCDI-B), and undertook this cross-sectional study aiming to 1) measure agreement among clinicians' mTBI diagnosis ratings, 2) using clinician consensus develop a fully structured diagnostic algorithm, and 3) assess accuracy of this algorithm in a separate sample. Two samples (n = 66; n = 37) of individuals within 2 years of experiencing blast effects during military deployment underwent semistructured interview regarding their worst blast experience. Five highly trained TBI physicians independently reviewed and interpreted the interview content and gave blinded ratings of whether or not the experience was probably an mTBI. Paired inter-rater reliability was extremely variable, with kappa ranging from 0.194 to 0.825. In sample 1, the physician consensus prevalence of probable mTBI was 84%. Using these diagnosis ratings, an algorithm was developed and refined from the fully structured portion of the VCU rCDI-B. The final algorithm considered certain symptom patterns more specific for mTBI than others. For example, an isolated symptom of "saw stars" was deemed sufficient to indicate mTBI, whereas an isolated symptom of "dazed" was not. The accuracy of this algorithm, when applied against the actual physician consensus in sample 2, was almost perfect (correctly classified = 97%; Cohen's kappa = 0.91). In conclusion, we found that highly trained clinicians often disagree on historical blast-related mTBI determinations. A fully structured interview

  3. Lightning Jump Algorithm Development for the GOES·R Geostationary Lightning Mapper

    NASA Technical Reports Server (NTRS)

    Schultz. E.; Schultz. C.; Chronis, T.; Stough, S.; Carey, L.; Calhoun, K.; Ortega, K.; Stano, G.; Cecil, D.; Bateman, M.; Goodman, S.

    2014-01-01

    Current work on the lightning jump algorithm to be used in GOES-R Geostationary Lightning Mapper (GLM)'s data stream is multifaceted due to the intricate interplay between the storm tracking, GLM proxy data, and the performance of the lightning jump itself. This work outlines the progress of the last year, where analysis and performance of the lightning jump algorithm with automated storm tracking and GLM proxy data were assessed using over 700 storms from North Alabama. The cases analyzed coincide with previous semi-objective work performed using total lightning mapping array (LMA) measurements in Schultz et al. (2011). Analysis shows that key components of the algorithm (flash rate and sigma thresholds) have the greatest influence on the performance of the algorithm when validating using severe storm reports. Automated objective analysis using the GLM proxy data has shown probability of detection (POD) values around 60% with false alarm rates (FAR) around 73% using similar methodology to Schultz et al. (2011). However, when applying verification methods similar to those employed by the National Weather Service, POD values increase slightly (69%) and FAR values decrease (63%). The relationship between storm tracking and lightning jump has also been tested in a real-time framework at NSSL. This system includes fully automated tracking by radar alone, real-time LMA and radar observations and the lightning jump. Results indicate that the POD is strong at 65%. However, the FAR is significantly higher than in Schultz et al. (2011) (50-80% depending on various tracking/lightning jump parameters) when using storm reports for verification. Given known issues with Storm Data, the performance of the real-time jump algorithm is also being tested with high density radar and surface observations from the NSSL Severe Hazards Analysis & Verification Experiment (SHAVE).

  4. Passive microwave remote sensing of rainfall with SSM/I: Algorithm development and implementation

    NASA Technical Reports Server (NTRS)

    Ferriday, James G.; Avery, Susan K.

    1994-01-01

    A physically based algorithm sensitive to emission and scattering is used to estimate rainfall using the Special Sensor Microwave/Imager (SSM/I). The algorithm is derived from radiative transfer calculations through an atmospheric cloud model specifying vertical distributions of ice and liquid hydrometeors as a function of rain rate. The algorithm is structured in two parts: SSM/I brightness temperatures are screened to detect rainfall and are then used in rain-rate calculation. The screening process distinguishes between nonraining background conditions and emission and scattering associated with hydrometeors. Thermometric temperature and polarization thresholds determined from the radiative transfer calculations are used to detect rain, whereas the rain-rate calculation is based on a linear function fit to a linear combination of channels. Separate calculations for ocean and land account for different background conditions. The rain-rate calculation is constructed to respond to both emission and scattering, reduce extraneous atmospheric and surface effects, and to correct for beam filling. The resulting SSM/I rain-rate estimates are compared to three precipitation radars as well as to a dynamically simulated rainfall event. Global estimates from the SSM/I algorithm are also compared to continental and shipboard measurements over a 4-month period. The algorithm is found to accurately describe both localized instantaneous rainfall events and global monthly patterns over both land and ovean. Over land the 4-month mean difference between SSM/I and the Global Precipitation Climatology Center continental rain gauge database is less than 10%. Over the ocean, the mean difference between SSM/I and the Legates and Willmott global shipboard rain gauge climatology is less than 20%.

  5. Decoding neural events from fMRI BOLD signal: A comparison of existing approaches and development of a new algorithm

    PubMed Central

    Bush, Keith; Cisler, Josh

    2013-01-01

    Neuroimaging methodology predominantly relies on the blood oxygenation level dependent (BOLD) signal. While the BOLD signal is a valid measure of neuronal activity, variance in fluctuations of the BOLD signal are not only due to fluctuations in neural activity. Thus, a remaining problem in neuroimaging analyses is developing methods that ensure specific inferences about neural activity that are not confounded by unrelated sources of noise in the BOLD signal. Here, we develop and test a new algorithm for performing semi-blind (i.e., no knowledge of stimulus timings) deconvolution of the BOLD signal that treats the neural event as an observable, but intermediate, probabilistic representation of the system’s state. We test and compare this new algorithm against three other recent deconvolution algorithms under varied levels of autocorrelated and Gaussian noise, hemodynamic response function (HRF) misspecification, and observation sampling rate (i.e., TR). Further, we compare the algorithms’ performance using two models to simulate BOLD data: a convolution of neural events with a known (or misspecified) HRF versus a biophysically accurate balloon model of hemodynamics. We also examine the algorithms’ performance on real task data. The results demonstrated good performance of all algorithms, though the new algorithm generally outperformed the others (3.0% improvement) under simulated resting state experimental conditions exhibiting multiple, realistic confounding factors (as well as 10.3% improvement on a real Stroop task). The simulations also demonstrate that the greatest negative influence on deconvolution accuracy is observation sampling rate. Practical and theoretical implications of these results for improving inferences about neural activity from fMRI BOLD signal are discussed. PMID:23602664

  6. TH-E-BRE-07: Development of Dose Calculation Error Predictors for a Widely Implemented Clinical Algorithm

    SciTech Connect

    Egan, A; Laub, W

    2014-06-15

    Purpose: Several shortcomings of the current implementation of the analytic anisotropic algorithm (AAA) may lead to dose calculation errors in highly modulated treatments delivered to highly heterogeneous geometries. Here we introduce a set of dosimetric error predictors that can be applied to a clinical treatment plan and patient geometry in order to identify high risk plans. Once a problematic plan is identified, the treatment can be recalculated with more accurate algorithm in order to better assess its viability. Methods: Here we focus on three distinct sources dosimetric error in the AAA algorithm. First, due to a combination of discrepancies in smallfield beam modeling as well as volume averaging effects, dose calculated through small MLC apertures can be underestimated, while that behind small MLC blocks can overestimated. Second, due the rectilinear scaling of the Monte Carlo generated pencil beam kernel, energy is not properly transported through heterogeneities near, but not impeding, the central axis of the beamlet. And third, AAA overestimates dose in regions very low density (< 0.2 g/cm{sup 3}). We have developed an algorithm to detect the location and magnitude of each scenario within the patient geometry, namely the field-size index (FSI), the heterogeneous scatter index (HSI), and the lowdensity index (LDI) respectively. Results: Error indices successfully identify deviations between AAA and Monte Carlo dose distributions in simple phantom geometries. Algorithms are currently implemented in the MATLAB computing environment and are able to run on a typical RapidArc head and neck geometry in less than an hour. Conclusion: Because these error indices successfully identify each type of error in contrived cases, with sufficient benchmarking, this method can be developed into a clinical tool that may be able to help estimate AAA dose calculation errors and when it might be advisable to use Monte Carlo calculations.

  7. A novel hybrid classification model of genetic algorithms, modified k-Nearest Neighbor and developed backpropagation neural network.

    PubMed

    Salari, Nader; Shohaimi, Shamarina; Najafi, Farid; Nallappan, Meenakshii; Karishnarajah, Isthrinayagy

    2014-01-01

    Among numerous artificial intelligence approaches, k-Nearest Neighbor algorithms, genetic algorithms, and artificial neural networks are considered as the most common and effective methods in classification problems in numerous studies. In the present study, the results of the implementation of a novel hybrid feature selection-classification model using the above mentioned methods are presented. The purpose is benefitting from the synergies obtained from combining these technologies for the development of classification models. Such a combination creates an opportunity to invest in the strength of each algorithm, and is an approach to make up for their deficiencies. To develop proposed model, with the aim of obtaining the best array of features, first, feature ranking techniques such as the Fisher's discriminant ratio and class separability criteria were used to prioritize features. Second, the obtained results that included arrays of the top-ranked features were used as the initial population of a genetic algorithm to produce optimum arrays of features. Third, using a modified k-Nearest Neighbor method as well as an improved method of backpropagation neural networks, the classification process was advanced based on optimum arrays of the features selected by genetic algorithms. The performance of the proposed model was compared with thirteen well-known classification models based on seven datasets. Furthermore, the statistical analysis was performed using the Friedman test followed by post-hoc tests. The experimental findings indicated that the novel proposed hybrid model resulted in significantly better classification performance compared with all 13 classification methods. Finally, the performance results of the proposed model was benchmarked against the best ones reported as the state-of-the-art classifiers in terms of classification accuracy for the same data sets. The substantial findings of the comprehensive comparative study revealed that performance of the

  8. A novel hybrid classification model of genetic algorithms, modified k-Nearest Neighbor and developed backpropagation neural network.

    PubMed

    Salari, Nader; Shohaimi, Shamarina; Najafi, Farid; Nallappan, Meenakshii; Karishnarajah, Isthrinayagy

    2014-01-01

    Among numerous artificial intelligence approaches, k-Nearest Neighbor algorithms, genetic algorithms, and artificial neural networks are considered as the most common and effective methods in classification problems in numerous studies. In the present study, the results of the implementation of a novel hybrid feature selection-classification model using the above mentioned methods are presented. The purpose is benefitting from the synergies obtained from combining these technologies for the development of classification models. Such a combination creates an opportunity to invest in the strength of each algorithm, and is an approach to make up for their deficiencies. To develop proposed model, with the aim of obtaining the best array of features, first, feature ranking techniques such as the Fisher's discriminant ratio and class separability criteria were used to prioritize features. Second, the obtained results that included arrays of the top-ranked features were used as the initial population of a genetic algorithm to produce optimum arrays of features. Third, using a modified k-Nearest Neighbor method as well as an improved method of backpropagation neural networks, the classification process was advanced based on optimum arrays of the features selected by genetic algorithms. The performance of the proposed model was compared with thirteen well-known classification models based on seven datasets. Furthermore, the statistical analysis was performed using the Friedman test followed by post-hoc tests. The experimental findings indicated that the novel proposed hybrid model resulted in significantly better classification performance compared with all 13 classification methods. Finally, the performance results of the proposed model was benchmarked against the best ones reported as the state-of-the-art classifiers in terms of classification accuracy for the same data sets. The substantial findings of the comprehensive comparative study revealed that performance of the

  9. A Novel Hybrid Classification Model of Genetic Algorithms, Modified k-Nearest Neighbor and Developed Backpropagation Neural Network

    PubMed Central

    Salari, Nader; Shohaimi, Shamarina; Najafi, Farid; Nallappan, Meenakshii; Karishnarajah, Isthrinayagy

    2014-01-01

    Among numerous artificial intelligence approaches, k-Nearest Neighbor algorithms, genetic algorithms, and artificial neural networks are considered as the most common and effective methods in classification problems in numerous studies. In the present study, the results of the implementation of a novel hybrid feature selection-classification model using the above mentioned methods are presented. The purpose is benefitting from the synergies obtained from combining these technologies for the development of classification models. Such a combination creates an opportunity to invest in the strength of each algorithm, and is an approach to make up for their deficiencies. To develop proposed model, with the aim of obtaining the best array of features, first, feature ranking techniques such as the Fisher's discriminant ratio and class separability criteria were used to prioritize features. Second, the obtained results that included arrays of the top-ranked features were used as the initial population of a genetic algorithm to produce optimum arrays of features. Third, using a modified k-Nearest Neighbor method as well as an improved method of backpropagation neural networks, the classification process was advanced based on optimum arrays of the features selected by genetic algorithms. The performance of the proposed model was compared with thirteen well-known classification models based on seven datasets. Furthermore, the statistical analysis was performed using the Friedman test followed by post-hoc tests. The experimental findings indicated that the novel proposed hybrid model resulted in significantly better classification performance compared with all 13 classification methods. Finally, the performance results of the proposed model was benchmarked against the best ones reported as the state-of-the-art classifiers in terms of classification accuracy for the same data sets. The substantial findings of the comprehensive comparative study revealed that performance of the

  10. Algorithm Development and Validation of CDOM Properties for Estuarine and Continental Shelf Waters Along the Northeastern U.S. Coast

    NASA Technical Reports Server (NTRS)

    Mannino, Antonio; Novak, Michael G.; Hooker, Stanford B.; Hyde, Kimberly; Aurin, Dick

    2014-01-01

    An extensive set of field measurements have been collected throughout the continental margin of the northeastern U.S. from 2004 to 2011 to develop and validate ocean color satellite algorithms for the retrieval of the absorption coefficient of chromophoric dissolved organic matter (aCDOM) and CDOM spectral slopes for the 275:295 nm and 300:600 nm spectral range (S275:295 and S300:600). Remote sensing reflectance (Rrs) measurements computed from in-water radiometry profiles along with aCDOM() data are applied to develop several types of algorithms for the SeaWiFS and MODIS-Aqua ocean color satellite sensors, which involve least squares linear regression of aCDOM() with (1) Rrs band ratios, (2) quasi-analytical algorithm-based (QAA based) products of total absorption coefficients, (3) multiple Rrs bands within a multiple linear regression (MLR) analysis, and (4) diffuse attenuation coefficient (Kd). The relative error (mean absolute percent difference; MAPD) for the MLR retrievals of aCDOM(275), aCDOM(355), aCDOM(380), aCDOM(412) and aCDOM(443) for our study region range from 20.4-23.9 for MODIS-Aqua and 27.3-30 for SeaWiFS. Because of the narrower range of CDOM spectral slope values, the MAPD for the MLR S275:295 and QAA-based S300:600 algorithms are much lower ranging from 9.9 and 8.3 for SeaWiFS, respectively, and 8.7 and 6.3 for MODIS, respectively. Seasonal and spatial MODIS-Aqua and SeaWiFS distributions of aCDOM, S275:295 and S300:600 processed with these algorithms are consistent with field measurements and the processes that impact CDOM levels along the continental shelf of the northeastern U.S. Several satellite data processing factors correlate with higher uncertainty in satellite retrievals of aCDOM, S275:295 and S300:600 within the coastal ocean, including solar zenith angle, sensor viewing angle, and atmospheric products applied for atmospheric corrections. Algorithms that include ultraviolet Rrs bands provide a better fit to field measurements than

  11. Development of a Real-Time Pulse Processing Algorithm for TES-Based X-Ray Microcalorimeters

    NASA Technical Reports Server (NTRS)

    Tan, Hui; Hennig, Wolfgang; Warburton, William K.; Doriese, W. Bertrand; Kilbourne, Caroline A.

    2011-01-01

    We report here a real-time pulse processing algorithm for superconducting transition-edge sensor (TES) based x-ray microcalorimeters. TES-based. microca1orimeters offer ultra-high energy resolutions, but the small volume of each pixel requires that large arrays of identical microcalorimeter pixe1s be built to achieve sufficient detection efficiency. That in turn requires as much pulse processing as possible must be performed at the front end of readout electronics to avoid transferring large amounts of data to a host computer for post-processing. Therefore, a real-time pulse processing algorithm that not only can be implemented in the readout electronics but also achieve satisfactory energy resolutions is desired. We have developed an algorithm that can be easily implemented. in hardware. We then tested the algorithm offline using several data sets acquired with an 8 x 8 Goddard TES x-ray calorimeter array and 2x16 NIST time-division SQUID multiplexer. We obtained an average energy resolution of close to 3.0 eV at 6 keV for the multiplexed pixels while preserving over 99% of the events in the data sets.

  12. Development of sleep apnea syndrome screening algorithm by using heart rate variability analysis and support vector machine.

    PubMed

    Nakayama, Chikao; Fujiwara, Koichi; Matsuo, Masahiro; Kano, Manabu; Kadotani, Hiroshi

    2015-08-01

    Although sleep apnea syndrome (SAS) is a common sleep disorder, most patients with sleep apnea are undiagnosed and untreated because it is difficult for patients themselves to notice SAS in daily living. Polysomnography (PSG) is a gold standard test for sleep disorder diagnosis, however PSG cannot be performed in many hospitals. This fact motivates us to develop an SAS screening system that can be used easily at home. The autonomic nervous function of a patient changes during apnea. Since changes in the autonomic nervous function affect fluctuation of the R-R interval (RRI) of an electrocardiogram (ECG), called heart rate variability (HRV), SAS can be detected through monitoring HRV. The present work proposes a new HRV-based SAS screening algorithm by utilizing support vector machine (SVM), which is a well-known pattern recognition method. In the proposed algorithm, various HRV features are derived from RRI data in both apnea and normal respiration periods of patients and healthy people, and an apnea/normal respiration (A/N) discriminant model is built from the derived HRV features by SVM. The result of applying the proposed SAS screening algorithm to clinical data demonstrates that it can discriminate patients with sleep apnea and healthy people appropriately. The sensitivity and the specificity of the proposed algorithm were 100% and 86%, respectively.

  13. Development and application of an algorithm for detecting Phaeocystis globosa blooms in the Case 2 Southern North Sea waters

    PubMed Central

    Astoreca, Rosa; Rousseau, Véronique; Ruddick, Kevin; Knechciak, Cécile; Van Mol, Barbara; Parent, Jean-Yves; Lancelot, Christiane

    2009-01-01

    While mapping algal blooms from space is now well-established, mapping undesirable algal blooms in eutrophicated coastal waters raises further challenge in detecting individual phytoplankton species. In this paper, an algorithm is developed and tested for detecting Phaeocystis globosa blooms in the Southern North Sea. For this purpose, we first measured the light absorption properties of two phytoplankton groups, P. globosa and diatoms, in laboratory-controlled experiments. The main spectral difference between both groups was observed at 467 nm due to the absorption of the pigment chlorophyll c3 only present in P. globosa, suggesting that the absorption at 467 nm can be used to detect this alga in the field. A Phaeocystis-detection algorithm is proposed to retrieve chlorophyll c3 using either total absorption or water-leaving reflectance field data. Application of this algorithm to absorption and reflectance data from Phaeocystis-dominated natural communities shows positive results. Comparison with pigment concentrations and cell counts suggests that the algorithm can flag the presence of P. globosa and provide quantitative information above a chlorophyll c3 threshold of 0.3 mg m−3 equivalent to a P. globosa cell density of 3 × 106 cells L−1. Finally, the possibility of extrapolating this information to remote sensing reflectance data in these turbid waters is evaluated. PMID:19461860

  14. The development of a line-scan imaging algorithm for the detection of fecal contamination on leafy geens

    NASA Astrophysics Data System (ADS)

    Yang, Chun-Chieh; Kim, Moon S.; Chuang, Yung-Kun; Lee, Hoyoung

    2013-05-01

    This paper reports the development of a multispectral algorithm, using the line-scan hyperspectral imaging system, to detect fecal contamination on leafy greens. Fresh bovine feces were applied to the surfaces of washed loose baby spinach leaves. A hyperspectral line-scan imaging system was used to acquire hyperspectral fluorescence images of the contaminated leaves. Hyperspectral image analysis resulted in the selection of the 666 nm and 688 nm wavebands for a multispectral algorithm to rapidly detect feces on leafy greens, by use of the ratio of fluorescence intensities measured at those two wavebands (666 nm over 688 nm). The algorithm successfully distinguished most of the lowly diluted fecal spots (0.05 g feces/ml water and 0.025 g feces/ml water) and some of the highly diluted spots (0.0125 g feces/ml water and 0.00625 g feces/ml water) from the clean spinach leaves. The results showed the potential of the multispectral algorithm with line-scan imaging system for application to automated food processing lines for food safety inspection of leafy green vegetables.

  15. Feather Development Genes and Associated Regulatory Innovation Predate the Origin of Dinosauria

    PubMed Central

    Lowe, Craig B.; Clarke, Julia A.; Baker, Allan J.; Haussler, David; Edwards, Scott V.

    2015-01-01

    The evolution of avian feathers has recently been illuminated by fossils and the identification of genes involved in feather patterning and morphogenesis. However, molecular studies have focused mainly on protein-coding genes. Using comparative genomics and more than 600,000 conserved regulatory elements, we show that patterns of genome evolution in the vicinity of feather genes are consistent with a major role for regulatory innovation in the evolution of feathers. Rates of innovation at feather regulatory elements exhibit an extended period of innovation with peaks in the ancestors of amniotes and archosaurs. We estimate that 86% of such regulatory elements and 100% of the nonkeratin feather gene set were present prior to the origin of Dinosauria. On the branch leading to modern birds, we detect a strong signal of regulatory innovation near insulin-like growth factor binding protein (IGFBP) 2 and IGFBP5, which have roles in body size reduction, and may represent a genomic signature for the miniaturization of dinosaurian body size preceding the origin of flight. PMID:25415961

  16. Feather development genes and associated regulatory innovation predate the origin of Dinosauria.

    PubMed

    Lowe, Craig B; Clarke, Julia A; Baker, Allan J; Haussler, David; Edwards, Scott V

    2015-01-01

    The evolution of avian feathers has recently been illuminated by fossils and the identification of genes involved in feather patterning and morphogenesis. However, molecular studies have focused mainly on protein-coding genes. Using comparative genomics and more than 600,000 conserved regulatory elements, we show that patterns of genome evolution in the vicinity of feather genes are consistent with a major role for regulatory innovation in the evolution of feathers. Rates of innovation at feather regulatory elements exhibit an extended period of innovation with peaks in the ancestors of amniotes and archosaurs. We estimate that 86% of such regulatory elements and 100% of the nonkeratin feather gene set were present prior to the origin of Dinosauria. On the branch leading to modern birds, we detect a strong signal of regulatory innovation near insulin-like growth factor binding protein (IGFBP) 2 and IGFBP5, which have roles in body size reduction, and may represent a genomic signature for the miniaturization of dinosaurian body size preceding the origin of flight.

  17. The design and development of signal-processing algorithms for an airborne x-band Doppler weather radar

    NASA Technical Reports Server (NTRS)

    Nicholson, Shaun R.

    1994-01-01

    Improved measurements of precipitation will aid our understanding of the role of latent heating on global circulations. Spaceborne meteorological sensors such as the planned precipitation radar and microwave radiometers on the Tropical Rainfall Measurement Mission (TRMM) provide for the first time a comprehensive means of making these global measurements. Pre-TRMM activities include development of precipitation algorithms using existing satellite data, computer simulations, and measurements from limited aircraft campaigns. Since the TRMM radar will be the first spaceborne precipitation radar, there is limited experience with such measurements, and only recently have airborne radars become available that can attempt to address the issue of the limitations of a spaceborne radar. There are many questions regarding how much attenuation occurs in various cloud types and the effect of cloud vertical motions on the estimation of precipitation rates. The EDOP program being developed by NASA GSFC will provide data useful for testing both rain-retrieval algorithms and the importance of vertical motions on the rain measurements. The purpose of this report is to describe the design and development of real-time embedded parallel algorithms used by EDOP to extract reflectivity and Doppler products (velocity, spectrum width, and signal-to-noise ratio) as the first step in the aforementioned goals.

  18. Ocean Observations with EOS/MODIS: Algorithm Development and Post Launch Studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.; Conboy, B. (Technical Monitor)

    1999-01-01

    Significant accomplishments made during the present reporting period include: 1) Installed spectral optimization algorithm in the SeaDas image processing environment and successfully processed SeaWiFS imagery. The results were superior to the standard SeaWiFS algorithm (the MODIS prototype) in a turbid atmosphere off the US East Coast, but similar in a clear (typical) oceanic atmosphere; 2) Inverted ACE-2 LIDAR measurements coupled with sun photometer-derived aerosol optical thickness to obtain the vertical profile of aerosol optical thickness. The profile was validated with simultaneous aircraft measurements; and 3) Obtained LIDAR and CIMEL measurements of typical maritime and mineral dust-dominated marine atmosphere in the U.S. Virgin Islands. Contemporaneous SeaWiFS imagery were also acquired.

  19. Development of an anthropomorphic breast software phantom based on region growing algorithm

    NASA Astrophysics Data System (ADS)

    Zhang, Cuiping; Bakic, Predrag R.; Maidment, Andrew D. A.

    2008-03-01

    Software breast phantoms offer greater flexibility in generating synthetic breast images compared to physical phantoms. The realism of such generated synthetic images depends on the method for simulating the three-dimensional breast anatomical structures. We present here a novel algorithm for computer simulation of breast anatomy. The algorithm simulates the skin, regions of predominantly adipose tissue and fibro-glandular tissue, and the matrix of adipose tissue compartments and Cooper's ligaments. The simulation approach is based upon a region growing procedure; adipose compartments are grown from a selected set of seed points with different orientation and growth rate. The simulated adipose compartments vary in shape and size similarly to the anatomical breast variation, resulting in much improved phantom realism compared to our previous simulation based on geometric primitives. The proposed simulation also has an improved control over the breast size and glandularity. Our software breast phantom has been used in a number of applications, including breast tomosynthesis and texture analysis optimization.

  20. Ocean observations with EOS/MODIS: Algorithm development and post launch studies

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1996-01-01

    An investigation of the influence of stratospheric aerosol on the performance of the atmospheric correction algorithm is nearly complete. The results indicate how the performance of the algorithm is degraded if the stratospheric aerosol is ignored. Use of the MODIS 1380 nm band to effect a correction for stratospheric aerosols was also studied. Simple algorithms such as subtracting the reflectance at 1380 nm from the visible and near infrared bands can significantly reduce the error; however, only if the diffuse transmittance of the aerosol layer is taken into account. The atmospheric correction code has been modified for use with absorbing aerosols. Tests of the code showed that, in contrast to non absorbing aerosols, the retrievals were strongly influenced by the vertical structure of the aerosol, even when the candidate aerosol set was restricted to a set appropriate to the absorbing aerosol. This will further complicate the problem of atmospheric correction in an atmosphere with strongly absorbing aerosols. Our whitecap radiometer system and solar aureole camera were both tested at sea and performed well. Investigation of a technique to remove the effects of residual instrument polarization sensitivity were initiated and applied to an instrument possessing (approx.) 3-4 times the polarization sensitivity expected for MODIS. Preliminary results suggest that for such an instrument, elimination of the polarization effect is possible at the required level of accuracy by estimating the polarization of the top-of-atmosphere radiance to be that expected for a pure Rayleigh scattering atmosphere. This may be of significance for design of a follow-on MODIS instrument. W.M. Balch participated on two month-long cruises to the Arabian sea, measuring coccolithophore abundance, production, and optical properties. A thorough understanding of the relationship between calcite abundance and light scatter, in situ, will provide the basis for a generic suspended calcite algorithm.

  1. Selection and collection of multi parameter physiological data for cardiac rhythm diagnostic algorithm development

    NASA Astrophysics Data System (ADS)

    Bostock, J.; Weller, P.; Cooklin, M.

    2010-07-01

    Automated diagnostic algorithms are used in implantable cardioverter-defibrillators (ICD's) to detect abnormal heart rhythms. Algorithms misdiagnose and improved specificity is needed to prevent inappropriate therapy. Knowledge engineering (KE) and artificial intelligence (AI) could improve this. A pilot study of KE was performed with artificial neural network (ANN) as AI system. A case note review analysed arrhythmic events stored in patients ICD memory. 13.2% patients received inappropriate therapy. The best ICD algorithm had sensitivity 1.00, specificity 0.69 (p<0.001 different to gold standard). A subset of data was used to train and test an ANN. A feed-forward, back-propagation network with 7 inputs, a 4 node hidden layer and 1 output had sensitivity 1.00, specificity 0.71 (p<0.001). A prospective study was performed using KE to list arrhythmias, factors and indicators for which measurable parameters were evaluated and results reviewed by a domain expert. Waveforms from electrodes in the heart and thoracic bio-impedance; temperature and motion data were collected from 65 patients during cardiac electrophysiological studies. 5 incomplete datasets were due to technical failures. We concluded that KE successfully guided selection of parameters and ANN produced a usable system and that complex data collection carries greater risk of technical failure, leading to data loss.

  2. Development and validation of a novel pedometer algorithm to quantify extended characteristics of the locomotor behavior of dairy cows.

    PubMed

    Alsaaod, M; Niederhauser, J J; Beer, G; Zehner, N; Schuepbach-Regula, G; Steiner, A

    2015-09-01

    Behavior is one of the most important indicators for assessing cattle health and well-being. The objective of this study was to develop and validate a novel algorithm to monitor locomotor behavior of loose-housed dairy cows based on the output of the RumiWatch pedometer (ITIN+HOCH GmbH, Fütterungstechnik, Liestal, Switzerland). Data of locomotion were acquired by simultaneous pedometer measurements at a sampling rate of 10 Hz and video recordings for manual observation later. The study consisted of 3 independent experiments. Experiment 1 was carried out to develop and validate the algorithm for lying behavior, experiment 2 for walking and standing behavior, and experiment 3 for stride duration and stride length. The final version was validated, using the raw data, collected from cows not included in the development of the algorithm. Spearman correlation coefficients were calculated between accelerometer variables and respective data derived from the video recordings (gold standard). Dichotomous data were expressed as the proportion of correctly detected events, and the overall difference for continuous data was expressed as the relative measurement error. The proportions for correctly detected events or bouts were 1 for stand ups, lie downs, standing bouts, and lying bouts and 0.99 for walking bouts. The relative measurement error and Spearman correlation coefficient for lying time were 0.09% and 1; for standing time, 4.7% and 0.96; for walking time, 17.12% and 0.96; for number of strides, 6.23% and 0.98; for stride duration, 6.65% and 0.75; and for stride length, 11.92% and 0.81, respectively. The strong to very high correlations of the variables between visual observation and converted pedometer data indicate that the novel RumiWatch algorithm may markedly improve automated livestock management systems for efficient health monitoring of dairy cows. PMID:26142842

  3. Development and characterisation of a state-of-the-art GOME-2 formaldehyde air-mass factor algorithm

    NASA Astrophysics Data System (ADS)

    Hewson, W.; Barkley, M. P.; Gonzalez Abad, G.; Bösch, H.; Kurosu, T.; Spurr, R.; Tilstra, L. G.

    2015-10-01

    Space-borne observations of formaldehyde (HCHO) are frequently used to derive surface emissions of isoprene, an important biogenic volatile organic compound. The conversion of retrieved HCHO slant column concentrations from satellite line-of-sight measurements to vertical columns is determined through application of an air mass factor (AMF), accounting for instrument viewing geometry, radiative transfer, and vertical profile of the absorber in the atmosphere. This step in the trace gas retrieval is subject to large errors. This work presents the AMF algorithm in use at the University of Leicester (UoL), which introduces scene-specific variables into a per-observation full radiative transfer AMF calculation, including increasing spatial resolution of key environmental parameter databases, input variable area weighting, instrument-specific scattering weight calculation, and inclusion of an ozone vertical profile climatology. Application of these updates to HCHO slant columns from the GOME-2 instrument is shown to typically adjust the AMF by ±20 %, compared to a reference algorithm without these advanced parameterisations. On average the GOME-2 AMFs increase by 4 %, with over 70 % of locations having an AMF of 0-20 % larger than originally, largely resulting from the use of the latest GOME-2 reflectance product. Furthermore, the new UoL algorithm also incorporates a full radiative transfer error calculation for each scene to help characterise AMF uncertainties. Global median AMF errors are typically 50-60 %, and are driven by uncertainties in the HCHO profile shape and its vertical distribution relative to clouds and aerosols. If uncertainty on the a priori HCHO profile is relatively small (< 10 %) then the median AMF total error decreases to about 30-40 %.

  4. Development and validation of a segmentation-free polyenergetic algorithm for dynamic perfusion computed tomography.

    PubMed

    Lin, Yuan; Samei, Ehsan

    2016-07-01

    Dynamic perfusion imaging can provide the morphologic details of the scanned organs as well as the dynamic information of blood perfusion. However, due to the polyenergetic property of the x-ray spectra, beam hardening effect results in undesirable artifacts and inaccurate CT values. To address this problem, this study proposes a segmentation-free polyenergetic dynamic perfusion imaging algorithm (pDP) to provide superior perfusion imaging. Dynamic perfusion usually is composed of two phases, i.e., a precontrast phase and a postcontrast phase. In the precontrast phase, the attenuation properties of diverse base materials (e.g., in a thorax perfusion exam, base materials can include lung, fat, breast, soft tissue, bone, and metal implants) can be incorporated to reconstruct artifact-free precontrast images. If patient motions are negligible or can be corrected by registration, the precontrast images can then be employed as a priori information to derive linearized iodine projections from the postcontrast images. With the linearized iodine projections, iodine perfusion maps can be reconstructed directly without the influence of various influential factors, such as iodine location, patient size, x-ray spectrum, and background tissue type. A series of simulations were conducted on a dynamic iodine calibration phantom and a dynamic anthropomorphic thorax phantom to validate the proposed algorithm. The simulations with the dynamic iodine calibration phantom showed that the proposed algorithm could effectively eliminate the beam hardening effect and enable quantitative iodine map reconstruction across various influential factors. The error range of the iodine concentration factors ([Formula: see text]) was reduced from [Formula: see text] for filtered back-projection (FBP) to [Formula: see text] for pDP. The quantitative results of the simulations with the dynamic anthropomorphic thorax phantom indicated that the maximum error of iodine concentrations can be reduced from

  5. Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus).

    PubMed

    Schroeder, Hilke; Cronn, Richard; Yanbaev, Yulai; Jennings, Tara; Mader, Malte; Degen, Bernd; Kersten, Birgit

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs); 189 insertion/deletion (indel) polymorphism) from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America), and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites) and Q. robur (346 variant sites). Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose) electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber. PMID:27352242

  6. Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus)

    PubMed Central

    Schroeder, Hilke; Cronn, Richard; Yanbaev, Yulai; Jennings, Tara; Mader, Malte; Degen, Bernd; Kersten, Birgit

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs); 189 insertion/deletion (indel) polymorphism) from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America), and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites) and Q. robur (346 variant sites). Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose) electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber. PMID:27352242

  7. 1 + 1 = 3: Development and validation of a SNP-based algorithm to identify genetic contributions from three distinct inbred mouse strains.

    PubMed

    Gorham, James D; Ranson, Matthew S; Smith, Janebeth C; Gorham, Beverly J; Muirhead, Kristen-Ashley

    2012-12-01

    State-of-the-art, genome-wide assessment of mouse genetic background uses single nucleotide polymorphism (SNP) PCR. As SNP analysis can use multiplex testing, it is amenable to high-throughput analysis and is the preferred method for shared resource facilities that offer genetic background assessment of mouse genomes. However, a typical individual SNP query yields only two alleles (A vs. B), limiting the application of this methodology to distinguishing contributions from no more than two inbred mouse strains. By contrast, simple sequence length polymorphism (SSLP) analysis yields multiple alleles but is not amenable to high-throughput testing. We sought to devise a SNP-based technique to identify donor strain origins when three distinct mouse strains potentially contribute to the genetic makeup of an individual mouse. A computational approach was used to devise a three-strain analysis (3SA) algorithm that would permit identification of three genetic backgrounds while still using a binary-output SNP platform. A panel of 15 mosaic mice with contributions from BALB/c, C57Bl/6, and DBA/2 genetic backgrounds was bred and analyzed using a genome-wide SNP panel using 1449 markers. The 3SA algorithm was applied and then validated using SSLP. The 3SA algorithm assigned 85% of 1449 SNPs as informative for the C57Bl/6, BALB/c, or DBA/2 backgrounds, respectively. Testing the panel of 15 F2 mice, the 3SA algorithm predicted donor strain origins genome-wide. Donor strain origins predicted by the 3SA algorithm correlated perfectly with results from individual SSLP markers located on five different chromosomes (n=70 tests). We have established and validated an analysis algorithm based on binary SNP data that can successfully identify the donor strain origins of chromosomal regions in mice that are bred from three distinct inbred mouse strains. PMID:23204929

  8. Drowsiness/alertness algorithm development and validation using synchronized EEG and cognitive performance to individualize a generalized model

    PubMed Central

    Johnson, Robin R.; Popovic, Djordje P.; Olmstead, Richard E.; Stikic, Maja; Levendowski, Daniel J.; Berka, Chris

    2011-01-01

    A great deal of research over the last century has focused on drowsiness/alertness detection, as fatigue-related physical and cognitive impairments pose a serious risk to public health and safety. Available drowsiness/alertness detection solutions are unsatisfactory for a number of reasons: 1) lack of generalizability, 2) failure to address individual variability in generalized models, and/or 3) they lack a portable, un-tethered application. The current study aimed to address these issues, and determine if an individualized electroencephalography (EEG) based algorithm could be defined to track performance decrements associated with sleep loss, as this is the first step in developing a field deployable drowsiness/alertness detection system. The results indicated that an EEG-based algorithm, individualized using a series of brief "identification" tasks, was able to effectively track performance decrements associated with sleep deprivation. Future development will address the need for the algorithm to predict performance decrements due to sleep loss, and provide field applicability. PMID:21419826

  9. Development and comparative assessment of Raman spectroscopic classification algorithms for lesion discrimination in stereotactic breast biopsies with microcalcifications

    PubMed Central

    Dingari, Narahara Chari; Barman, Ishan; Saha, Anushree; McGee, Sasha; Galindo, Luis H.; Liu, Wendy; Plecha, Donna; Klein, Nina; Dasari, Ramachandra Rao; Fitzmaurice, Maryann

    2014-01-01

    Microcalcifications are an early mammographic sign of breast cancer and a target for stereotactic breast needle biopsy. Here, we develop and compare different approaches for developing Raman classification algorithms to diagnose invasive and in situ breast cancer, fibrocystic change and fibroadenoma that can be associated with microcalcifications. In this study, Raman spectra were acquired from tissue cores obtained from fresh breast biopsies and analyzed using a constituent-based breast model. Diagnostic algorithms based on the breast model fit coefficients were devised using logistic regression, C4.5 decision tree classification, k-nearest neighbor (k-NN) and support vector machine (SVM) analysis, and subjected to leave-one-out cross validation. The best performing algorithm was based on SVM analysis (with radial basis function), which yielded a positive predictive value of 100% and negative predictive value of 96% for cancer diagnosis. Importantly, these results demonstrate that Raman spectroscopy provides adequate diagnostic information for lesion discrimination even in the presence of microcalcifications, which to the best of our knowledge has not been previously reported. Raman spectroscopy and multivariate classification provide accurate discrimination among lesions in stereotactic breast biopsies, irrespective of microcalcification status. PMID:22815240

  10. Development of a remote sensing algorithm for cyanobacterial phycocyanin pigment in the Baltic Sea using neural network approach

    NASA Astrophysics Data System (ADS)

    Riha, Stefan; Krawczyk, Harald

    2011-11-01

    Water quality monitoring in the Baltic Sea is of high ecological importance for all its neighbouring countries. They are highly interested in a regular monitoring of water quality parameters of their regional zones. A special attention is paid to the occurrence and dissemination of algae blooms. Among the appearing blooms the possibly toxicological or harmful cyanobacteria cultures are a special case of investigation, due to their specific optical properties and due to the negative influence on the ecological state of the aquatic system. Satellite remote sensing, with its high temporal and spatial resolution opportunities, allows the frequent observations of large areas of the Baltic Sea with special focus on its two seasonal algae blooms. For a better monitoring of the cyanobacteria dominated summer blooms, adapted algorithms are needed which take into account the special optical properties of blue-green algae. Chlorophyll-a standard algorithms typically fail in a correct recognition of these occurrences. To significantly improve the opportunities of observation and propagation of the cyanobacteria blooms, the Marine Remote Sensing group of DLR has started the development of a model based inversion algorithm that includes a four component bio-optical water model for Case2 waters, which extends the commonly calculated parameter set chlorophyll, Suspended Matter and CDOM with an additional parameter for the estimation of phycocyanin absorption. It was necessary to carry out detailed optical laboratory measurements with different cyanobacteria cultures, occurring in the Baltic Sea, for the generation of a specific bio-optical model. The inversion of satellite remote sensing data is based on an artificial Neural Network technique. This is a model based multivariate non-linear inversion approach. The specifically designed Neural Network is trained with a comprehensive dataset of simulated reflectance values taking into account the laboratory obtained specific optical

  11. Watershed model calibration framework developed using an influence coefficient algorithm and a genetic algorithm and analysis of pollutant discharge characteristics and load reduction in a TMDL planning area.

    PubMed

    Cho, Jae Heon; Lee, Jong Ho

    2015-11-01

    Manual calibration is common in rainfall-runoff model applications. However, rainfall-runoff models include several complicated parameters; thus, significant time and effort are required to manually calibrate the parameters individually and repeatedly. Automatic calibration has relative merit regarding time efficiency and objectivity but shortcomings regarding understanding indigenous processes in the basin. In this study, a watershed model calibration framework was developed using an influence coefficient algorithm and genetic algorithm (WMCIG) to automatically calibrate the distributed models. The optimization problem used to minimize the sum of squares of the normalized residuals of the observed and predicted values was solved using a genetic algorithm (GA). The final model parameters were determined from the iteration with the smallest sum of squares of the normalized residuals of all iterations. The WMCIG was applied to a Gomakwoncheon watershed located in an area that presents a total maximum daily load (TMDL) in Korea. The proportion of urbanized area in this watershed is low, and the diffuse pollution loads of nutrients such as phosphorus are greater than the point-source pollution loads because of the concentration of rainfall that occurs during the summer. The pollution discharges from the watershed were estimated for each land-use type, and the seasonal variations of the pollution loads were analyzed. Consecutive flow measurement gauges have not been installed in this area, and it is difficult to survey the flow and water quality in this area during the frequent heavy rainfall that occurs during the wet season. The Hydrological Simulation Program-Fortran (HSPF) model was used to calculate the runoff flow and water quality in this basin. Using the water quality results, a load duration curve was constructed for the basin, the exceedance frequency of the water quality standard was calculated for each hydrologic condition class, and the percent reduction

  12. Watershed model calibration framework developed using an influence coefficient algorithm and a genetic algorithm and analysis of pollutant discharge characteristics and load reduction in a TMDL planning area.

    PubMed

    Cho, Jae Heon; Lee, Jong Ho

    2015-11-01

    Manual calibration is common in rainfall-runoff model applications. However, rainfall-runoff models include several complicated parameters; thus, significant time and effort are required to manually calibrate the parameters individually and repeatedly. Automatic calibration has relative merit regarding time efficiency and objectivity but shortcomings regarding understanding indigenous processes in the basin. In this study, a watershed model calibration framework was developed using an influence coefficient algorithm and genetic algorithm (WMCIG) to automatically calibrate the distributed models. The optimization problem used to minimize the sum of squares of the normalized residuals of the observed and predicted values was solved using a genetic algorithm (GA). The final model parameters were determined from the iteration with the smallest sum of squares of the normalized residuals of all iterations. The WMCIG was applied to a Gomakwoncheon watershed located in an area that presents a total maximum daily load (TMDL) in Korea. The proportion of urbanized area in this watershed is low, and the diffuse pollution loads of nutrients such as phosphorus are greater than the point-source pollution loads because of the concentration of rainfall that occurs during the summer. The pollution discharges from the watershed were estimated for each land-use type, and the seasonal variations of the pollution loads were analyzed. Consecutive flow measurement gauges have not been installed in this area, and it is difficult to survey the flow and water quality in this area during the frequent heavy rainfall that occurs during the wet season. The Hydrological Simulation Program-Fortran (HSPF) model was used to calculate the runoff flow and water quality in this basin. Using the water quality results, a load duration curve was constructed for the basin, the exceedance frequency of the water quality standard was calculated for each hydrologic condition class, and the percent reduction

  13. Study report on interfacing major physiological subsystem models: An approach for developing a whole-body algorithm

    NASA Technical Reports Server (NTRS)

    Fitzjerrell, D. G.; Grounds, D. J.; Leonard, J. I.

    1975-01-01

    Using a whole body algorithm simulation model, a wide variety and large number of stresses as well as different stress levels were simulated including environmental disturbances, metabolic changes, and special experimental situations. Simulation of short term stresses resulted in simultaneous and integrated responses from the cardiovascular, respiratory, and thermoregulatory subsystems and the accuracy of a large number of responding variables was verified. The capability of simulating significantly longer responses was demonstrated by validating a four week bed rest study. In this case, the long term subsystem model was found to reproduce many experimentally observed changes in circulatory dynamics, body fluid-electrolyte regulation, and renal function. The value of systems analysis and the selected design approach for developing a whole body algorithm was demonstrated.

  14. Waveband selection and algorithm development to distinguish fecal contamination using multispectral imaging with solar light

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fecal contamination in fresh produce fields caused by animals or livestock entering the fields can lead to outbreaks of foodbourne illnesses. E.coli O157:H7 originating in the intestines of animals can transfer onto leafy greens via fecal matter. Leafy greens are often eaten fresh without thermal tr...

  15. Data and software tools for gamma radiation spectral threat detection and nuclide identification algorithm development and evaluation

    NASA Astrophysics Data System (ADS)

    Portnoy, David; Fisher, Brian; Phifer, Daniel

    2015-06-01

    The detection of radiological and nuclear threats is extremely important to national security. The federal government is spending significant resources developing new detection systems and attempting to increase the performance of existing ones. The detection of illicit radionuclides that may pose a radiological or nuclear threat is a challenging problem complicated by benign radiation sources (e.g., cat litter and medical treatments), shielding, and large variations in background radiation. Although there is a growing acceptance within the community that concentrating efforts on algorithm development (independent of the specifics of fully assembled systems) has the potential for significant overall system performance gains, there are two major hindrances to advancements in gamma spectral analysis algorithms under the current paradigm: access to data and common performance metrics along with baseline performance measures. Because many of the signatures collected during performance measurement campaigns are classified, dissemination to algorithm developers is extremely limited. This leaves developers no choice but to collect their own data if they are lucky enough to have access to material and sensors. This is often combined with their own definition of metrics for measuring performance. These two conditions make it all but impossible for developers and external reviewers to make meaningful comparisons between algorithms. Without meaningful comparisons, performance advancements become very hard to achieve and (more importantly) recognize. The objective of this work is to overcome these obstacles by developing and freely distributing real and synthetically generated gamma-spectra data sets as well as software tools for performance evaluation with associated performance baselines to national labs, academic institutions, government agencies, and industry. At present, datasets for two tracks, or application domains, have been developed: one that includes temporal

  16. The Universal Decimal Classification: Some Factors Concerning Its Origins, Development, and Influence.

    ERIC Educational Resources Information Center

    McIlwaine, I. C.

    1997-01-01

    Discusses the history and development of the Universal Decimal Classification (UDC). Topics include the relationship with Dewey Decimal Classification; revision process; structure; facet analysis; lack of standard rules for application; application in automated systems; influence of UDC on classification development; links with thesauri; and use…

  17. The Origins and Development of the National Training Center, 1976-1984. TRADOC Historical Monograph Series.

    ERIC Educational Resources Information Center

    Chapman, Anne W.

    Focusing on the development of the United States Army's National Training Center (NTC) from conceptualization and initial implementation in 1981 to the end of the first phase of development in 1984, this monograph provides a documented historical analysis of how and why the landmark event in army training was launched and examines attendant policy…

  18. Litter of origin effects on gilt development in a commercial setting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The preweaning litter environment of gilts can affect subsequent development. In a recent experiment designed to test the effects of dietary ME and lysine on gilt development, individual birth weights, immunocrits (related to colostrum intake), sow parity, number weaned, individual weaning weights, ...

  19. Origin and Development of Industrial Education at Alcorn Agricultural and Mechanical College.

    ERIC Educational Resources Information Center

    Smith, Jay T.

    This study covering the last 100 years in the development of industrial education at Alcorn Agricultural and Mechanical College was prompted by the need to determine the role of the college in the development of industrial education in the state of Mississippi. Sources of data included college catalogs, reports of the college administration and…

  20. Use of a Stochastic Joint Inversion Modeling Algorithm to Develop a Hydrothermal Flow Model at a Geothermal Prospect

    NASA Astrophysics Data System (ADS)

    Tompson, A. F. B.; Mellors, R. J.; Dyer, K.; Yang, X.; Chen, M.; Trainor Guitton, W.; Wagoner, J. L.; Ramirez, A. L.

    2014-12-01

    A stochastic joint inverse algorithm is used to analyze diverse geophysical and hydrologic data associated with a geothermal prospect. The approach uses a Markov Chain Monte Carlo (MCMC) global search algorithm to develop an ensemble of hydrothermal groundwater flow models that are most consistent with the observations. The algorithm utilizes an initial conceptual model descriptive of structural (geology), parametric (permeability) and hydrothermal (saturation, temperature) characteristics of the geologic system. Initial (a-priori) estimates of uncertainty in these characteristics are used to drive simulations of hydrothermal fluid flow and related geophysical processes in a large number of random realizations of the conceptual geothermal system spanning these uncertainties. The process seeks to improve the conceptual model by developing a ranked subset of model realizations that best match all available data within a specified norm or tolerance. Statistical (posterior) characteristics of these solutions reflect reductions in the a-priori uncertainties. The algorithm has been tested on a geothermal prospect located at Superstition Mountain, California and has been successful in creating a suite of models compatible with available temperature, surface resistivity, and magnetotelluric (MT) data. Although the MCMC method is highly flexible and capable of accommodating multiple and diverse datasets, a typical inversion may require the evaluation of thousands of possible model runs whose sophistication and complexity may evolve with the magnitude of data considered. As a result, we are testing the use of sensitivity analyses to better identify critical uncertain variables, lower order surrogate models to streamline computational costs, and value of information analyses to better assess optimal use of related data. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL

  1. Development of an apnea detection algorithm based on temporal analysis of thoracic respiratory effort signal

    NASA Astrophysics Data System (ADS)

    Dell'Aquila, C. R.; Cañadas, G. E.; Correa, L. S.; Laciar, E.

    2016-04-01

    This work describes the design of an algorithm for detecting apnea episodes, based on analysis of thorax respiratory effort signal. Inspiration and expiration time, and range amplitude of respiratory cycle were evaluated. For range analysis the standard deviation statistical tool was used over respiratory signal temporal windows. The validity of its performance was carried out in 8 records of Apnea-ECG database that has annotations of apnea episodes. The results are: sensitivity (Se) 73%, specificity (Sp) 83%. These values can be improving eliminating artifact of signal records.

  2. Robust integration schemes for generalized viscoplasticity with internal-state variables. Part 2: Algorithmic developments and implementation

    NASA Technical Reports Server (NTRS)

    Li, Wei; Saleeb, Atef F.

    1995-01-01

    This two-part report is concerned with the development of a general framework for the implicit time-stepping integrators for the flow and evolution equations in generalized viscoplastic models. The primary goal is to present a complete theoretical formulation, and to address in detail the algorithmic and numerical analysis aspects involved in its finite element implementation, as well as to critically assess the numerical performance of the developed schemes in a comprehensive set of test cases. On the theoretical side, the general framework is developed on the basis of the unconditionally-stable, backward-Euler difference scheme as a starting point. Its mathematical structure is of sufficient generality to allow a unified treatment of different classes of viscoplastic models with internal variables. In particular, two specific models of this type, which are representative of the present start-of-art in metal viscoplasticity, are considered in applications reported here; i.e., fully associative (GVIPS) and non-associative (NAV) models. The matrix forms developed for both these models are directly applicable for both initially isotropic and anisotropic materials, in general (three-dimensional) situations as well as subspace applications (i.e., plane stress/strain, axisymmetric, generalized plane stress in shells). On the computational side, issues related to efficiency and robustness are emphasized in developing the (local) interative algorithm. In particular, closed-form expressions for residual vectors and (consistent) material tangent stiffness arrays are given explicitly for both GVIPS and NAV models, with their maximum sizes 'optimized' to depend only on the number of independent stress components (but independent of the number of viscoplastic internal state parameters). Significant robustness of the local iterative solution is provided by complementing the basic Newton-Raphson scheme with a line-search strategy for convergence. In the present second part of

  3. SeaWiFS Technical Report Series. Volume 42; Satellite Primary Productivity Data and Algorithm Development: A Science Plan for Mission to Planet Earth

    NASA Technical Reports Server (NTRS)

    Falkowski, Paul G.; Behrenfeld, Michael J.; Esaias, Wayne E.; Balch, William; Campbell, Janet W.; Iverson, Richard L.; Kiefer, Dale A.; Morel, Andre; Yoder, James A.; Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor)

    1998-01-01

    Two issues regarding primary productivity, as it pertains to the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Program and the National Aeronautics and Space Administration (NASA) Mission to Planet Earth (MTPE) are presented in this volume. Chapter 1 describes the development of a science plan for deriving primary production for the world ocean using satellite measurements, by the Ocean Primary Productivity Working Group (OPPWG). Chapter 2 presents discussions by the same group, of algorithm classification, algorithm parameterization and data availability, algorithm testing and validation, and the benefits of a consensus primary productivity algorithm.

  4. Common origins of diverse misconceptions: cognitive principles and the development of biology thinking.

    PubMed

    Coley, John D; Tanner, Kimberly D

    2012-01-01

    Many ideas in the biological sciences seem especially difficult to understand, learn, and teach successfully. Our goal in this feature is to explore how these difficulties may stem not from the complexity or opacity of the concepts themselves, but from the fact that they may clash with informal, intuitive, and deeply held ways of understanding the world that have been studied for decades by psychologists. We give a brief overview of the field of developmental cognitive psychology. Then, in each of the following sections, we present a number of common challenges faced by students in the biological sciences. These may be in the form of misconceptions, biases, or simply concepts that are difficult to learn and teach, and they occur at all levels of biological analysis (molecular, cellular, organismal, population, and ecosystem). We then introduce the notion of a cognitive construal and discuss specific examples of how these cognitive principles may explain what makes some misconceptions so alluring and some biological concepts so challenging for undergraduates. We will argue that seemingly unrelated misconceptions may have common origins in a single underlying cognitive construal. These ideas emerge from our own ongoing cross-disciplinary conversation, and we think that expanding this conversation to include other biological scientists and educators, as well as other cognitive scientists, could have significant utility in improving biology teaching and learning.

  5. Common Origins of Diverse Misconceptions: Cognitive Principles and the Development of Biology Thinking

    PubMed Central

    Coley, John D.; Tanner, Kimberly D.

    2012-01-01

    Many ideas in the biological sciences seem especially difficult to understand, learn, and teach successfully. Our goal in this feature is to explore how these difficulties may stem not from the complexity or opacity of the concepts themselves, but from the fact that they may clash with informal, intuitive, and deeply held ways of understanding the world that have been studied for decades by psychologists. We give a brief overview of the field of developmental cognitive psychology. Then, in each of the following sections, we present a number of common challenges faced by students in the biological sciences. These may be in the form of misconceptions, biases, or simply concepts that are difficult to learn and teach, and they occur at all levels of biological analysis (molecular, cellular, organismal, population, and ecosystem). We then introduce the notion of a cognitive construal and discuss specific examples of how these cognitive principles may explain what makes some misconceptions so alluring and some biological concepts so challenging for undergraduates. We will argue that seemingly unrelated misconceptions may have common origins in a single underlying cognitive construal. These ideas emerge from our own ongoing cross-disciplinary conversation, and we think that expanding this conversation to include other biological scientists and educators, as well as other cognitive scientists, could have significant utility in improving biology teaching and learning. PMID:22949417

  6. Development of micro-flow hydrothermal monitoring systems and their applications to the origin of life study on Earth.

    PubMed

    Kawamura, Kunio

    2011-01-01

    Continuous extensive studies on thermophilic organisms have suggested that life emerged on hydrothermal systems on primitive Earth. Thus, it is well known that hydrothermal reactions are, therefore, very important to study fields deeply related to the origin-of-life study. Furthermore, the importance of hydrothermal and solvothermal systems is now realized in both fundamental and practical areas. Here, our recent investigations are described for the development of real-time and in situ monitoring systems for hydrothermal reactions. The systems were primarily developed for the origin-of-life study, but it was also applicable to fundamental and practical areas. The present techniques are based on the concept that a sample solution is injected to a narrow tubing flow reactor at high temperatures, where the sample is rapidly heated up in a very short time by exposure at to a high-temperature narrow tubing flow reactor with a very short time scale. This enables millisecond to second time-scale monitoring in real time and/or in situ at temperatures of up to 400°C. By using these techniques, a series of studies on the hydrothermal origin-of-life have been successfully carried out.

  7. Stream-reach Identification for New Run-of-River Hydropower Development through a Merit Matrix Based Geospatial Algorithm

    SciTech Connect

    Pasha, M. Fayzul K.; Yeasmin, Dilruba; Kao, Shih-Chieh; Hadjerioua, Boualem; Wei, Yaxing; Smith, Brennan T

    2014-01-01

    Even after a century of development, the total hydropower potential from undeveloped rivers is still considered to be abundant in the United States. However, unlike evaluating hydropower potential at existing hydropower plants or non-powered dams, locating a feasible new hydropower plant involves many unknowns, and hence the total undeveloped potential is harder to quantify. In light of the rapid development of multiple national geospatial datasets for topography, hydrology, and environmental characteristics, a merit matrix based geospatial algorithm is proposed to help identify possible hydropower stream-reaches for future development. These hydropower stream-reaches sections of natural streams with suitable head, flow, and slope for possible future development are identified and compared using three different scenarios. A case study was conducted in the Alabama-Coosa-Tallapoosa (ACT) and Apalachicola-Chattahoochee-Flint (ACF) hydrologic subregions. It was found that a merit matrix based algorithm, which is based on the product of hydraulic head, annual mean flow, and average channel slope, can help effectively identify stream-reaches with high power density and small surface inundation. The identified stream-reaches can then be efficiently evaluated for their potential environmental impact, land development cost, and other competing water usage in detailed feasibility studies . Given that the selected datasets are available nationally (at least within the conterminous US), the proposed methodology will have wide applicability across the country.

  8. The early origins of food preferences: targeting the critical windows of development.

    PubMed

    Gugusheff, Jessica Rose; Ong, Zhi Yi; Muhlhausler, Beverly Sara

    2015-02-01

    The nutritional environment to which an individual is exposed during the perinatal period plays a crucial role in determining his or her future metabolic health outcomes. Studies in rodent models have demonstrated that excess maternal intake of high-fat and/or high-sugar "junk foods" during pregnancy and lactation can alter the development of the central reward pathway, particularly the opioid and dopamine systems, and program an increased preference for junk foods in the offspring. More recently, there have been attempts to define the critical windows of development during which the opioid and dopamine systems within the reward pathway are most susceptible to alteration and to determine whether it is possible to reverse these effects through nutritional interventions applied later in development. This review discusses the progress made to date in these areas, highlights the apparent importance of sex in determining these effects, and considers the potential implications of the findings from rodent models in the human context.

  9. Evidence-Based Skin Care: A Systematic Literature Review and the Development of a Basic Skin Care Algorithm.

    PubMed

    Lichterfeld, Andrea; Hauss, Armin; Surber, Christian; Peters, Tina; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-01-01

    Patients in acute and long-term care settings receive daily routine skin care, including washing, bathing, and showering, often followed by application of lotions, creams, and/or ointments. These personal hygiene and skin care activities are integral parts of nursing practice, but little is known about their benefits or clinical efficacy. The aim of this article was to summarize the empirical evidence supporting basic skin care procedures and interventions and to develop a clinical algorithm for basic skin care. Electronic databases MEDLINE, EMBASE, and CINAHL were searched and afterward a forward search was conducted using Scopus and Web of Science. In order to evaluate a broad range of basic skin care interventions systematic reviews, intervention studies, and guidelines, consensus statements and best practice standards also were included in the analysis. One hundred twenty-one articles were read in full text; 41documents were included in this report about skin care for prevention of dry skin, prevention of incontinence-associated dermatitis and prevention of skin injuries. The methodological quality of the included publications was variable. Review results and expert input were used to create a clinical algorithm for basic skin care. A 2-step approach is proposed including general and special skin care. Interventions focus primarily on skin that is either too dry or too moist. The target groups for the algorithm are adult patients or residents with intact or preclinical damaged skin in care settings. The goal of the skin care algorithm is a first attempt to provide guidance for practitioners to improve basic skin care in clinical settings in order to maintain or increase skin health.

  10. Development of Interpretation Algorithm for Optical Fiber Bragg Grating Sensors for Composite Structures

    NASA Astrophysics Data System (ADS)

    Peters, Kara

    2002-12-01

    Increasingly, optical fiber sensors, and in particular Bragg grating sensors, are being used in aerospace structures due to their immunity to electrical noise and the ability to multiplex hundreds of sensors into a single optical fiber. This significantly reduces the cost per sensor as the number of fiber connections and demodulation systems required is also reduced. The primary objective of this project is to study the effects of mounting issues such as adhesion, surface roughness, and high strain gradients on the interpretation of the measured strain. This is performed through comparison with electrical strain gage benchmark data. The long-term goal is to integrate such optical fiber Bragg grating sensors into a structural integrity monitoring system for the 2nd Generation Reusable Launch Vehicle. Previously, researchers at NASA Langley instrumented a composite wingbox with both optical fiber Bragg grating sensors and electrical strain gages during laboratory load-to-failure testing. A considerable amount of data was collected during these tests. For this project, data from two of the sensing optical fibers (each containing 800 Bragg grating sensors) were analyzed in detail. The first fiber studied was mounted in a straight line on the upper surface of the wingbox far from any structural irregularities. The results from these sensors showed a relatively large amount of noise compared to the electrical strain gages, but measured the same averaged strain curve. It was shown that the noise could be varied through the choice of input parameters in the data interpretation algorithm. Based upon the assumption that the strain remains constant along the gage length (a valid assumption for this fiber as confirmed by the measured grating spectra) this noise was significantly reduced. The second fiber was mounted on the lower surface of the wingbox in a pattern that circled surface cutouts and ran close to sites of impact damage, induced before the loading tests. As

  11. Detection of surface algal blooms using the newly developed algorithm surface algal bloom index (SABI)

    NASA Astrophysics Data System (ADS)

    Alawadi, Fahad

    2010-10-01

    Quantifying ocean colour properties has evolved over the past two decades from being able to merely detect their biological activity to the ability to estimate chlorophyll concentration using optical satellite sensors like MODIS and MERIS. The production of chlorophyll spatial distribution maps is a good indicator of plankton biomass (primary production) and is useful for the tracing of oceanographic currents, jets and blooms, including harmful algal blooms (HABs). Depending on the type of HABs involved and the environmental conditions, if their concentration rises above a critical threshold, it can impact the flora and fauna of the aquatic habitat through the introduction of the so called "red tide" phenomenon. The estimation of chlorophyll concentration is derived from quantifying the spectral relationship between the blue and the green bands reflected from the water column. This spectral relationship is employed in the standard ocean colour chlorophyll-a (Chlor-a) product, but is incapable of detecting certain macro-algal species that float near to or at the water surface in the form of dense filaments or mats. The ability to accurately identify algal formations that sometimes appear as oil spill look-alikes in satellite imagery, contributes towards the reduction of false-positive incidents arising from oil spill monitoring operations. Such algal formations that occur in relatively high concentrations may experience, as in land vegetation, what is known as the "red-edge" effect. This phenomena occurs at the highest reflectance slope between the maximum absorption in the red due to the surrounding ocean water and the maximum reflectance in the infra-red due to the photosynthetic pigments present in the surface algae. A new algorithm termed the surface algal bloom index (SABI), has been proposed to delineate the spatial distributions of floating micro-algal species like for example cyanobacteria or exposed inter-tidal vegetation like seagrass. This algorithm was

  12. MUlti-Dimensional Spline-Based Estimator (MUSE) for motion estimation: algorithm development and initial results.

    PubMed

    Viola, Francesco; Coe, Ryan L; Owen, Kevin; Guenther, Drake A; Walker, William F

    2008-12-01

    Image registration and motion estimation play central roles in many fields, including RADAR, SONAR, light microscopy, and medical imaging. Because of its central significance, estimator accuracy, precision, and computational cost are of critical importance. We have previously presented a highly accurate, spline-based time delay estimator that directly determines sub-sample time delay estimates from sampled data. The algorithm uses cubic splines to produce a continuous representation of a reference signal and then computes an analytical matching function between this reference and a delayed signal. The location of the minima of this function yields estimates of the time delay. In this paper we describe the MUlti-dimensional Spline-based Estimator (MUSE) that allows accurate and precise estimation of multi-dimensional displacements/strain components from multi-dimensional data sets. We describe the mathematical formulation for two- and three-dimensional motion/strain estimation and present simulation results to assess the intrinsic bias and standard deviation of this algorithm and compare it to currently available multi-dimensional estimators. In 1000 noise-free simulations of ultrasound data we found that 2D MUSE exhibits maximum bias of 2.6 x 10(-4) samples in range and 2.2 x 10(-3) samples in azimuth (corresponding to 4.8 and 297 nm, respectively). The maximum simulated standard deviation of estimates in both dimensions was comparable at roughly 2.8 x 10(-3) samples (corresponding to 54 nm axially and 378 nm laterally). These results are between two and three orders of magnitude better than currently used 2D tracking methods. Simulation of performance in 3D yielded similar results to those observed in 2D. We also present experimental results obtained using 2D MUSE on data acquired by an Ultrasonix Sonix RP imaging system with an L14-5/38 linear array transducer operating at 6.6 MHz. While our validation of the algorithm was performed using ultrasound data, MUSE is

  13. Javascript Library for Developing Interactive Micro-Level Animations for Teaching and Learning Algorithms on One-Dimensional Arrays

    ERIC Educational Resources Information Center

    Végh, Ladislav

    2016-01-01

    The first data structure that first-year undergraduate students learn during the programming and algorithms courses is the one-dimensional array. For novice programmers, it might be hard to understand different algorithms on arrays (e.g. searching, mirroring, sorting algorithms), because the algorithms dynamically change the values of elements. In…

  14. Identity Development Theories in Student Affairs: Origins, Current Status, and New Approaches

    ERIC Educational Resources Information Center

    Torres, Vasti; Jones, Susan R.; Renn, Kristen A.

    2009-01-01

    This article focuses on understanding how identity development is conceptualized in student affairs. The need to understand the person, context, and interactions between the two advances identity theories as relevant to student affairs practice. The more practitioners understand how students make meaning of their identities, the better they are…

  15. The Origins and Development of the Diffusion of Innovations Paradigm as an Example of Scientific Growth.

    ERIC Educational Resources Information Center

    Valente, Thomas W.; Rogers, Everett M.

    1995-01-01

    Describes some of the history of rural sociological research on the diffusion of agricultural innovations, and shows how research followed (and deviated from) the Kuhnian concept of paradigm development. Examines the Iowa Hybrid Seed Corn Study which contributed to the rise of sociological diffusion research. (103 references) (AEF)

  16. Developing and Implementing an Interdisciplinary Origins Course at a State University

    ERIC Educational Resources Information Center

    Miller, Keith; Totten, Iris

    2009-01-01

    A truly interdisciplinary course was successfully developed and taught that presented an overview of the historical sciences with an emphasis on the nature of scientific inquiry and its relationship to other ways of knowing. The course included contributions from faculty in physics, biology, geology, philosophy, and English. (Contains 2 figures.)

  17. Engines of Economic Development: The Origins and Evolution of Iowa's Comprehensive Community Colleges

    ERIC Educational Resources Information Center

    Friedel, Janice

    2010-01-01

    One of the most remarkable developments in American education in the past half century has been the creation and rapid growth of the nation's community colleges. Built on the curricular pillars of vocational education, transfer programs, and community education, community colleges today are considered the "engines of statewide economic growth"…

  18. Geology of the Thaumasia region, Mars: Plateau development, valley origins, and magmatic evolution

    USGS Publications Warehouse

    Dohm, J.M.; Tanaka, K.L.

    1999-01-01

    rock occurs there. The overall volcanotectonic history at Thaumasia fits into a model for Tharsis as a whole in which long-lived Syria Planum-centered activity is ringed by a few significant, shorter-lived centers of activity like the Thaumasia plateau. Valley formation, like tectonism in the region, peaked during the Noachian and declined substantially during the Hesperian and Amazonian. Temporal and spatial associations of single erosional valleys and valley networks with volcanoes, rift systems, and large impact craters suggest that the majority of valleys formed by hydrothermal, deformational, and seismic-induced processes. The origin of scattered, mainly Noachian valleys is more conjectural; possible explanations include local precipitation, seismic disturbance of aquifers, or unrecognized intrusions. ?? 1999 Elsevier Science Ltd. All rights reserved.

  19. Development of a Genetic Algorithm to Automate Clustering of a Dependency Structure Matrix

    NASA Technical Reports Server (NTRS)

    Rogers, James L.; Korte, John J.; Bilardo, Vincent J.

    2006-01-01

    Much technology assessment and organization design data exists in Microsoft Excel spreadsheets. Tools are needed to put this data into a form that can be used by design managers to make design decisions. One need is to cluster data that is highly coupled. Tools such as the Dependency Structure Matrix (DSM) and a Genetic Algorithm (GA) can be of great benefit. However, no tool currently combines the DSM and a GA to solve the clustering problem. This paper describes a new software tool that interfaces a GA written as an Excel macro with a DSM in spreadsheet format. The results of several test cases are included to demonstrate how well this new tool works.

  20. Development of a Multiview Time Domain Imaging Algorithm (MTDI) with a Fermat Correction

    SciTech Connect

    Fisher, K A; Lehman, S K; Chambers, D H

    2004-09-22

    An imaging algorithm is presented based on the standard assumption that the total scattered field can be separated into an elastic component with monopole like dependence and an inertial component with a dipole like dependence. The resulting inversion generates two separate image maps corresponding to the monopole and dipole terms of the forward model. The complexity of imaging flaws and defects in layered elastic media is further compounded by the existence of high contrast gradients in either sound speed and/or density from layer to layer. To compensate for these gradients, we have incorporated Fermat's method of least time into our forward model to determine the appropriate delays between individual source-receiver pairs. Preliminary numerical and experimental results are in good agreement with each other.

  1. Development of an Interval Management Algorithm Using Ground Speed Feedback for Delayed Traffic

    NASA Technical Reports Server (NTRS)

    Barmore, Bryan E.; Swieringa, Kurt A.; Underwood, Matthew C.; Abbott, Terence; Leonard, Robert D.

    2016-01-01

    One of the goals of NextGen is to enable frequent use of Optimized Profile Descents (OPD) for aircraft, even during periods of peak traffic demand. NASA is currently testing three new technologies that enable air traffic controllers to use speed adjustments to space aircraft during arrival and approach operations. This will allow an aircraft to remain close to their OPD. During the integration of these technologies, it was discovered that, due to a lack of accurate trajectory information for the leading aircraft, Interval Management aircraft were exhibiting poor behavior. NASA's Interval Management algorithm was modified to address the impact of inaccurate trajectory information and a series of studies were performed to assess the impact of this modification. These studies show that the modification provided some improvement when the Interval Management system lacked accurate trajectory information for the leading aircraft.

  2. A novel sensing method and sensing algorithm development for a ubiquitous network.

    PubMed

    Jabbar, Hamid; Lee, Sungju; Choi, Seunghwan; Baek, Seunghyun; Yu, Sungwook; Jeong, Taikyeong

    2010-01-01

    This paper proposes a novel technique which provides energy efficient circuit design for sensors networks. The overall system presented requires a minimum number of independently communicating sensors and sub-circuits which enable it to reduce the power consumption by setting unused sensors to idle. This technique reduces hardware requirements, time and interconnection problems with a supervisory control. Our proposed algorithm, which hands over the controls to two software mangers for the sensing and moving subsystems can greatly improve the overall system performance. Based on the experimental results, we observed that our system, which is using sensing and moving managers, the four sensors required only 3.4 mW power consumption when a robot arm is moved a total distance of 17 cm. This system is designed for robot applications but could be implemented to many other human environments such as "ubiquitous cities", "smart homes", etc.

  3. Development of a SiPM-based PET detector using a digital positioning algorithm

    NASA Astrophysics Data System (ADS)

    Lee, Jin Hyung; Lee, Seung-Jae; An, Su Jung; Kim, Hyun-Il; Chung, Yong Hyun

    2016-05-01

    A decreased number of readout method is investigated here to provide precise pixel information for small-animal positron emission tomography (PET). Small-animal PET consists of eight modules, each being composed of a 3 × 3 array of 2 mm × 2 mm × 20 mm lutetium yttrium orthosilicate (LYSO) crystals optically coupled to a 2 × 2 array of 3 mm × 3 mm silicon photomultipliers (SiPMs). The number of readout channels is reduced by one-quarter that of the conventional method by applying a simplified pixel-determination algorithm. The performances of the PET system and detector module were evaluated with experimental verifications. In the results, all pixels of the 3 × 3 LYSO array were decoded well, and the performances of the PET detector module were measured.

  4. System design and algorithmic development for computational steering in distributed environments

    SciTech Connect

    Wu, Qishi; Zhu, Mengxia; Gu, Yi; Rao, Nageswara S

    2010-03-01

    Supporting visualization pipelines over wide-area networks is critical to enabling large-scale scientific applications that require visual feedback to interactively steer online computations. We propose a remote computational steering system that employs analytical models to estimate the cost of computing and communication components and optimizes the overall system performance in distributed environments with heterogeneous resources. We formulate and categorize the visualization pipeline configuration problems for maximum frame rate into three classes according to the constraints on node reuse or resource sharing, namely no, contiguous, and arbitrary reuse. We prove all three problems to be NP-complete and present heuristic approaches based on a dynamic programming strategy. The superior performance of the proposed solution is demonstrated with extensive simulation results in comparison with existing algorithms and is further evidenced by experimental results collected on a prototype implementation deployed over the Internet.

  5. Development of a prototype algorithm for the operational retrieval of height-resolved products from GOME

    NASA Technical Reports Server (NTRS)

    Spurr, Robert J. D.

    1997-01-01

    Global ozone monitoring experiment (GOME) level 2 products of total ozone column amounts have been generated on a routine operational basis since July 1996. These products and the level 1 radiance products are the major outputs from the ERS-2 ground segment GOME data processor (GDP) at DLR in Germany. Off-line scientific work has already shown the feasibility of ozone profile retrieval from GOME. It is demonstrated how the retrievals can be performed in an operational context. Height-resolved retrieval is based on the optimal estimation technique, #and cloud-contaminated scenes are treated in an equivalent reflecting surface approximation. The prototype must be able to handle GOME measurements routinely on a global basis. Requirements for the major components of the algorithm are described: this incorporates an overall strategy for operational height-resolved retrieval from GOME.

  6. Developing an Algorithm for Finding Deep-Sea Corals on Seamounts Using Bathymetry and Photographic Data

    NASA Astrophysics Data System (ADS)

    Fernandez, D. P.; Adkins, J. F.; Scheirer, D. P.

    2006-12-01

    Over the last three years we have conducted several cruises on seamounts in the North Atlantic to sample and characterize the distribution of deep-sea corals in space and time. Using the deep submergence vehicle Alvin and the ROV Hercules we have spent over 80 hours on the seafloor. With the autonomous vehicle ABE and a towed camera sled, we collected over 10,000 bottom photographs and over 60 hours of micro- bathymetry over 120 km of seafloor. While there are very few living scleractinia (Desmophyllum dianthus, Solenosmilia sp. and, Lophilia sp.), we recovered over 5,000 fossil D. dianthus and over 60 kg of fossil Solenosmilia sp. The large numbers of fossil corals mean that a perceived lack of material does not have to limit the use of this new archive of the deep ocean. However, we need a better strategy for finding and returning samples to the lab. Corals clearly prefer to grow on steep slopes and at the tops of scarps of all scales. They are preferentially found along ridges and on small knolls flanking a larger edifice. There is also a clear preference for D. dianthus to recruit onto carbonate substrate. Overall, our sample collection, bathymetry and bottom photographs allow us to create an algorithm for finding corals based only on knowledge of the seafloor topography. We can test this algorithm against known sampling locations and visual surveys of the seafloor. Similar to the way seismic data are used to locate ideal coring locations, we propose that high-resolution bathymetry can be used to predict the most likely locations for finding fossil deep-sea corals.

  7. Development of response models for the Earth Radiation Budget Experiment (ERBE) sensors. Part 4: Preliminary nonscanner models and count conversion algorithms

    NASA Technical Reports Server (NTRS)

    Halyo, Nesim; Choi, Sang H.

    1987-01-01

    Two count conversion algorithms and the associated dynamic sensor model for the M/WFOV nonscanner radiometers are defined. The sensor model provides and updates the constants necessary for the conversion algorithms, though the frequency with which these updates were needed was uncertain. This analysis therefore develops mathematical models for the conversion of irradiance at the sensor field of view (FOV) limiter into data counts, derives from this model two algorithms for the conversion of data counts to irradiance at the sensor FOV aperture and develops measurement models which account for a specific target source together with a sensor. The resulting algorithms are of the gain/offset and Kalman filter types. The gain/offset algorithm was chosen since it provided sufficient accuracy using simpler computations.

  8. [Assessment of the impact of GMO of plant origin on rat progeny development in 3 generations].

    PubMed

    Tyshko, N V; Zhminchenko, V M; Pashorina, V A; Seliaskin, K E; Saprykin, V P; Utembaeva, N T; Tutel'ian, V A

    2011-01-01

    The publication presents the results of assessment of impact of genetically modified (GM) maize Liberty Link on prenatal and postnatal development of progeny of 3 generations of Wistar rats. A total of 630 adult animals and 2837 pups were used in the experiment. The animals were divided into 5 groups which got the diets with inclusion of maize: the animals of the experimental group got the diet with the GM-maize, animals of the control group - with near isogenic conventional analogue of the GM-maize, animals of the 1st, 2nd and 3rd reference groups - conventional varieties of maize ROSS 144 MV, ROSS 197 MVW, Dokuchayevskaya 250 MV respectively. The maize was included in the diet at maximum possible level not violating the balance of basic nutrients. Analysis of the data obtained during the study did not reveal any impact of GM-maize on rat progeny development. PMID:21574464

  9. [Assessment of the impact of GMO of plant origin on rat progeny development in 3 generations].

    PubMed

    Tyshko, N V; Zhminchenko, V M; Pashorina, V A; Seliaskin, K E; Saprykin, V P; Utembaeva, N T; Tutel'ian, V A

    2011-01-01

    The publication presents the results of assessment of impact of genetically modified (GM) maize Liberty Link on prenatal and postnatal development of progeny of 3 generations of Wistar rats. A total of 630 adult animals and 2837 pups were used in the experiment. The animals were divided into 5 groups which got the diets with inclusion of maize: the animals of the experimental group got the diet with the GM-maize, animals of the control group - with near isogenic conventional analogue of the GM-maize, animals of the 1st, 2nd and 3rd reference groups - conventional varieties of maize ROSS 144 MV, ROSS 197 MVW, Dokuchayevskaya 250 MV respectively. The maize was included in the diet at maximum possible level not violating the balance of basic nutrients. Analysis of the data obtained during the study did not reveal any impact of GM-maize on rat progeny development.

  10. Current state of the art brachytherapy treatment planning dosimetry algorithms

    PubMed Central

    Pantelis, E; Karaiskos, P

    2014-01-01

    Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for 192Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice. PMID:25027247

  11. Origin and development of plasma membrane derived invaginations in Vinca rosea l.

    NASA Technical Reports Server (NTRS)

    Mahlberg, P.; Walkinshaw, C.; Olson, K.

    1971-01-01

    The occurrence, morphology, and possible ontogeny of plasma-membrane-related structures are described which can develop into invaginations or intravacuolar formations. An underlying study of meristematic tissues from the shoot of Vinca rosea supports the interpretation that endocytosis does occur in plant cells and that it is appropriate to refer to these structures as endocytoses. The function of these invaginations or their content remains to be elucidated.

  12. NASA Astrophysics Cosmic Origins (COR) and Physics of the Cosmos (PCOS) Strategic Technology Development Program

    NASA Astrophysics Data System (ADS)

    Pham, Thai; Seery, Bernard D.

    2015-01-01

    The COR and PCOS Program Offices (PO) reside at the NASA Goddard Space Flight Center (GSFC), serving as the NASA Astrophysics Division's implementation arm for matters relating to the two programs. One aspect of the PO's activities is managing the COR and PCOS Strategic Astrophysics Technology (SAT) program, helping mature technologies to enable and enhance future astrophysics missions.The PO is guided by the National Research Council's 'New Worlds, New Horizons in Astronomy and Astrophysics' Decadal Survey report, and NASA's Astrophysics Implementation Plan. Strategic goals include dark energy; gravitational waves; X-ray observatories, e.g., US participation in ATHENA; Inflation probe; and a large UV/Visible telescope.To date, 51 COR and 65 PCOS SAT proposals have been received, of which 11 COR and 18 PCOS projects were funded. Notable successes include maturation of a new far-IR detector, later adopted by the SOFIA HAWC instrument; maturation of the H4RG near-IR detector, adopted by WFIRST; development of an antenna-coupled transition-edge superconducting bolometer, a technology deployed by BICEP2 that allowed measurement of B-mode polarization in the CMB signal, a possible signature of Inflation; and finally, the REXIS instrument on OSIRIS-REx is incorporating CCDs with directly deposited optical blocking filters developed by another SAT-funded project.We discuss our technology development process, with community input and strategic prioritization informing calls for SAT proposals and guiding investment decisions. We also present results of this year's technology gap prioritization and showcase our current portfolio of technology development projects. These include five newly selected projects, kicking off in FY 2015.For more information, visit the COR Program website at cor.gsfc.nasa.gov and the PCOS website at pcos.gsfc.nasa.gov.

  13. Systematic stereoscopic analyses for cloacal development: The origin of anorectal malformations

    PubMed Central

    Matsumaru, Daisuke; Murashima, Aki; Fukushima, Junichi; Senda, Syuhei; Matsushita, Shoko; Nakagata, Naomi; Miyajima, Masayasu; Yamada, Gen

    2015-01-01

    The division of the embryonic cloaca is the most essential event for the formation of digestive and urinary tracts. The defective development of the cloaca results in anorectal malformations (ARMs; 2–5 per 10,000 live births). However, the developmental and pathogenic mechanisms of ARMs are unclear. In the current study, we visualized the epithelia in the developing cloaca and nephric ducts (NDs). Systemic stereoscopic analyses revealed that the ND-cloaca connection sites shifted from the lateral-middle to dorsal-anterior part of the cloaca during cloacal division from E10.5 to E11.5 in mouse embryos. Genetic cell labeling analyses revealed that the cells in the ventral cloacal epithelium in the early stages rarely contributed to the dorsal part. Moreover, we revealed the possible morphogenetic movement of endodermal cells within the anterior part of the urogenital sinus and hindgut. These results provide the basis for understanding both cloacal development and the ARM pathogenesis. PMID:26354024

  14. On the origins and development of evidence-based medicine and medical decision making.

    PubMed

    Elstein, A S

    2004-08-01

    The aims of this paper are to identify the issues and forces that were the impetus for two recent developments in academic medicine, evidence-based medicine (EBM) and medical decision making (MDM); to make explicit their underlying similarities and differences; and to relate them to the fates of these innovations. Both developments respond to concerns about practice variation; the rapid growth of medical technology, leading to a proliferation of diagnostic and treatment options; the patient empowerment movement; and psychological research that raised questions about the quality of human judgment and decision making. Their commonalities include: use of Bayesian principles in diagnostic reasoning, and the common structure embedded in an answerable clinical question and a decision tree. Major differences include: emphasis on knowledge or judgment as the fundamental problem; the status of formal models and utility assessment; and the spirit and tone of the innovation. These differences have led to broader acceptance of EBM within academic medicine, while decision analysis, the fundamental tool of MDM, has been less welcomed in clinical circles and has found its place in guideline development, cost-effectiveness analysis, and health policy.

  15. On the Ethnic Origins of African Development: Chiefs and Precolonial Political Centralization

    PubMed Central

    Michalopoulos, Stelios; Papaioannou, Elias

    2015-01-01

    We report on recent findings of a fruitful research agenda that explores the importance of ethnic-specific traits in shaping African development. First, using recent surveys from Sub-Saharan African countries, we document that individuals identify with their ethnic group as often as with the nation pointing to the salience of ethnicity. Second, we focus on the various historical and contemporary functions of tribal leaders (chiefs) and illustrate their influence on various aspects of the economy and the polity. Third, we elaborate on a prominent dimension of ethnicity, that of the degree of complexity of pre-colonial political organization. Building on insights from the African historiography, we review recent works showing a strong association between pre-colonial centralization and contemporary comparative development both across and within countries. We also document that the link between pre-colonial political centralization and regional development -as captured by satellite images of light density at night-is particularly strong in areas outside the vicinity of the capitals, where due to population mixing and the salience of national institutions ethnic traits play a lesser role. Overall, our evidence is supportive to theories and narratives on the presence of a “dual” economic and institutional environment in Africa. PMID:27011760

  16. Development of the applied mathematics originating from the group theory of physical and mathematical problems

    SciTech Connect

    Hyman, J.; Beyer, W.; Louck, J.; Metropolis, N.

    1996-07-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Group theoretical methods are a powerful tool both in their applications to mathematics and to physics. The broad goal of this project was to use such methods to develop the implications of group (symmetry) structures underlying models of physical systems, as well as to broaden the understanding of simple models of chaotic systems. The main thrust was to develop further the complex mathematics that enters into many-particle quantum systems with special emphasis on the new directions in applied mathematics that have emerged and continue to surface in these studies. In this area, significant advances in understanding the role of SU(2) 3nj-coefficients in SU(3) theory have been made and in using combinatoric techniques in the study of generalized Schur functions, discovered during this project. In the context of chaos, the study of maps of the interval and the associated theory of words has led to significant discoveries in Galois group theory, to the classification of fixed points, and to the solution of a problem in the classification of DNA sequences.

  17. Development of a Pedestrian Indoor Navigation System Based on Multi-Sensor Fusion and Fuzzy Logic Estimation Algorithms

    NASA Astrophysics Data System (ADS)

    Lai, Y. C.; Chang, C. C.; Tsai, C. M.; Lin, S. Y.; Huang, S. C.

    2015-05-01

    This paper presents a pedestrian indoor navigation system based on the multi-sensor fusion and fuzzy logic estimation algorithms. The proposed navigation system is a self-contained dead reckoning navigation that means no other outside signal is demanded. In order to achieve the self-contained capability, a portable and wearable inertial measure unit (IMU) has been developed. Its adopted sensors are the low-cost inertial sensors, accelerometer and gyroscope, based on the micro electro-mechanical system (MEMS). There are two types of the IMU modules, handheld and waist-mounted. The low-cost MEMS sensors suffer from various errors due to the results of manufacturing imperfections and other effects. Therefore, a sensor calibration procedure based on the scalar calibration and the least squares methods has been induced in this study to improve the accuracy of the inertial sensors. With the calibrated data acquired from the inertial sensors, the step length and strength of the pedestrian are estimated by multi-sensor fusion and fuzzy logic estimation algorithms. The developed multi-sensor fusion algorithm provides the amount of the walking steps and the strength of each steps in real-time. Consequently, the estimated walking amount and strength per step are taken into the proposed fuzzy logic estimation algorithm to estimates the step lengths of the user. Since the walking length and direction are both the required information of the dead reckoning navigation, the walking direction is calculated by integrating the angular rate acquired by the gyroscope of the developed IMU module. Both the walking length and direction are calculated on the IMU module and transmit to a smartphone with Bluetooth to perform the dead reckoning navigation which is run on a self-developed APP. Due to the error accumulating of dead reckoning navigation, a particle filter and a pre-loaded map of indoor environment have been applied to the APP of the proposed navigation system to extend its

  18. Development of an algorithm as an implementation model for a wound management formulary across a UK health economy.

    PubMed

    Stephen-Haynes, J

    2013-12-01

    This article outlines a strategic process for the evaluation of wound management products and the development of an algorithm as an implementation model for wound management. Wound management is an increasingly complex process given the variety of interactive dressings and other devices available. This article discusses the procurement process, access to wound management dressings and the use of wound management formularies within the UK. We conclude that the current commissioners of tissue viability within healthcare organisations need to adopt a proactive approach to ensure appropriate formulary evaluation and product selection, in order to achieve the most beneficial clinical and financial outcomes.

  19. Development of Fault Models for Hybrid Fault Detection and Diagnostics Algorithm: October 1, 2014 -- May 5, 2015

    SciTech Connect

    Cheung, Howard; Braun, James E.

    2015-12-31

    This report describes models of building faults created for OpenStudio to support the ongoing development of fault detection and diagnostic (FDD) algorithms at the National Renewable Energy Laboratory. Building faults are operating abnormalities that degrade building performance, such as using more energy than normal operation, failing to maintain building temperatures according to the thermostat set points, etc. Models of building faults in OpenStudio can be used to estimate fault impacts on building performance and to develop and evaluate FDD algorithms. The aim of the project is to develop fault models of typical heating, ventilating and air conditioning (HVAC) equipment in the United States, and the fault models in this report are grouped as control faults, sensor faults, packaged and split air conditioner faults, water-cooled chiller faults, and other uncategorized faults. The control fault models simulate impacts of inappropriate thermostat control schemes such as an incorrect thermostat set point in unoccupied hours and manual changes of thermostat set point due to extreme outside temperature. Sensor fault models focus on the modeling of sensor biases including economizer relative humidity sensor bias, supply air temperature sensor bias, and water circuit temperature sensor bias. Packaged and split air conditioner fault models simulate refrigerant undercharging, condenser fouling, condenser fan motor efficiency degradation, non-condensable entrainment in refrigerant, and liquid line restriction. Other fault models that are uncategorized include duct fouling, excessive infiltration into the building, and blower and pump motor degradation.

  20. Modeling Design Iteration in Product Design and Development and Its Solution by a Novel Artificial Bee Colony Algorithm

    PubMed Central

    2014-01-01

    Due to fierce market competition, how to improve product quality and reduce development cost determines the core competitiveness of enterprises. However, design iteration generally causes increases of product cost and delays of development time as well, so how to identify and model couplings among tasks in product design and development has become an important issue for enterprises to settle. In this paper, the shortcomings existing in WTM model are discussed and tearing approach as well as inner iteration method is used to complement the classic WTM model. In addition, the ABC algorithm is also introduced to find out the optimal decoupling schemes. In this paper, firstly, tearing approach and inner iteration method are analyzed for solving coupled sets. Secondly, a hybrid iteration model combining these two technologies is set up. Thirdly, a high-performance swarm intelligence algorithm, artificial bee colony, is adopted to realize problem-solving. Finally, an engineering design of a chemical processing system is given in order to verify its reasonability and effectiveness. PMID:25431584

  1. Placental development during early pregnancy in sheep: Effects of embryo origin on vascularization

    PubMed Central

    Grazul-Bilska, Anna T.; Johnson, Mary Lynn; Borowicz, Pawel P.; Bilski, Jerzy J.; Cymbaluk, Taylor; Norberg, Spencer; Redmer, Dale A.; Reynolds, Lawrence P.

    2014-01-01

    Utero-placental growth and vascular development are critical for pregnancy establishment that may be altered by various factors including assisted reproductive technologies (ART), nutrition, or others, leading to compromised pregnancy. We hypothesized that placental vascularization and expression of angiogenic factors are altered early in pregnancies after transfer of embryos created using selected ART methods. Pregnancies were achieved through natural mating (NAT), or transfer of embryos from natural mating (NAT-ET), or in vitro fertilization (IVF) or activation (IVA). Placental tissues were collected on day 22 of pregnancy. In maternal caruncles (CAR), vascular cell proliferation was less (P<0.05) for IVA than other groups. Compared to NAT, density of blood vessels was less (P<0.05) for IVF and IVA in fetal membranes (FM), and for NAT-ET, IVF and IVA in CAR. In FM, mRNA expression was decreased (P<0.01–0.08) in NAT-ET, IVF and IVA compared to NAT for vascular endothelial growth factor (VEGF) and its receptor FLT-1, placental growth factor (PGF), neuropilin (NP) 1 and 2, angiopoietin (ANGPT) 1 and 2, endothelial nitric oxide synthase (NOS3), hypoxia inducible factor-1A (HIF1A), fibroblast growth factor (FGF) 2 and its receptor FGFR2. In CAR, mRNA expression was decreased (P<0.01–0.05) in NAT-ET, IVF and IVA compared to NAT for VEGF, FLT-1, PGF, ANGPT1 and TEK. Decreased mRNA expression for 12 of 14 angiogenic factors across FM and CAR in NAT-ET, IVF and IVA pregnancies was associated with reduced placental vascular development, which would lead to poor placental function and compromised fetal and placental growth and development. PMID:24472816

  2. The Canadian Healthy Infant Longitudinal Development (CHILD) Study: examining developmental origins of allergy and asthma.

    PubMed

    Subbarao, Padmaja; Anand, Sonia S; Becker, Allan B; Befus, A Dean; Brauer, Michael; Brook, Jeffrey R; Denburg, Judah A; HayGlass, Kent T; Kobor, Michael S; Kollmann, Tobias R; Kozyrskyj, Anita L; Lou, W Y Wendy; Mandhane, Piushkumar J; Miller, Gregory E; Moraes, Theo J; Pare, Peter D; Scott, James A; Takaro, Tim K; Turvey, Stuart E; Duncan, Joanne M; Lefebvre, Diana L; Sears, Malcolm R

    2015-10-01

    The Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort study recruited 3624 pregnant women, most partners and 3542 eligible offspring. We hypothesise that early life physical and psychosocial environments, immunological, physiological, nutritional, hormonal and metabolic influences interact with genetics influencing allergic diseases, including asthma. Environmental and biological sampling, innate and adaptive immune responses, gene expression, DNA methylation, gut microbiome and nutrition studies complement repeated environmental and clinical assessments to age 5. This rich data set, linking prenatal and postnatal environments, diverse biological samples and rigorous phenotyping, will inform early developmental pathways to allergy, asthma and other chronic inflammatory diseases.

  3. [Elementary exploration of the origin and development of marine Chinese materia medica].

    PubMed

    Guan, Hua-Shi; Fu, Xian-Jun; Wu, Qiang-Ming; Wang, Chang-Yun; Wang, Yu; Jiang, Deng-Zhao

    2009-05-01

    According to archaeological discoveries, humans began to make use of marine natural resources early in the Palaeolithic era. In the Spring and Autumn period and Warring States period, they began to use marine life as medicines and also had simple cognitions on their efficacy and processing. In the Qin and Han dynasties, people further deepened the understanding of the marine Chinese materia medica and created prescriptions making use of marine drugs. In the Tang and Song period, the number of marine Chinese materia medica species and corresponding prescriptions apparently increased. The cognitions of the property, flavor, efficacy as well as the compatible principle of marine Chinese materia medica was further deepened and the scope of their treatment also significantly expanded. In the Ming and Qing dynasties, the cognition of the marine Chinese materia medica was mainly the conclusions of the previous experience. After the founding of the People's Republic of China (PRC), with the development of science and technologies, the ability of exploiting and utilizing the marine Chinese materia medica by people dramatically increased, and the species of marine Chinese materia medica reached more than one thousand. However, the development of marine Chinese materia medica is confronted with new problems; although the number of species of marine Chinese materia medica increased, the understanding of their property and flavor is obviously lagging behind, which seriously affects the clinical application of marine Chinese materia medica.

  4. Development of a phantom to validate high-dose-rate brachytherapy treatment planning systems with heterogeneous algorithms

    SciTech Connect

    Moura, Eduardo S.; Rostelato, Maria Elisa C. M.; Zeituni, Carlos A.

    2015-04-15

    Purpose: This work presents the development of a phantom to verify the treatment planning system (TPS) algorithms used for high-dose-rate (HDR) brachytherapy. It is designed to measure the relative dose in a heterogeneous media. The experimental details used, simulation methods, and comparisons with a commercial TPS are also provided. Methods: To simulate heterogeneous conditions, four materials were used: Virtual Water™ (VM), BR50/50™, cork, and aluminum. The materials were arranged in 11 heterogeneity configurations. Three dosimeters were used to measure the relative response from a HDR {sup 192}Ir source: TLD-100™, Gafchromic{sup ®} EBT3 film, and an Exradin™ A1SL ionization chamber. To compare the results from the experimental measurements, the various configurations were modeled in the PENELOPE/penEasy Monte Carlo code. Images of each setup geometry were acquired from a CT scanner and imported into BrachyVision™ TPS software, which includes a grid-based Boltzmann solver Acuros™. The results of the measurements performed in the heterogeneous setups were normalized to the dose values measured in the homogeneous Virtual Water™ setup and the respective differences due to the heterogeneities were considered. Additionally, dose values calculated based on the American Association of Physicists in Medicine-Task Group 43 formalism were compared to dose values calculated with the Acuros™ algorithm in the phantom. Calculated doses were compared at the same points, where measurements have been performed. Results: Differences in the relative response as high as 11.5% were found from the homogeneous setup when the heterogeneous materials were inserted into the experimental phantom. The aluminum and cork materials produced larger differences than the plastic materials, with the BR50/50™ material producing results similar to the Virtual Water™ results. Our experimental methods agree with the PENELOPE/penEasy simulations for most setups and dosimeters. The

  5. Sixty years of the Interamerican Society of Psychology (SIP): origins and development.

    PubMed

    Gallegos, Miguel

    2013-01-01

    This paper presents a historical overview of the Interamerican Society of Psychology, which was founded on December 17, 1951, in Mexico City. Firstly, the historical circumstances of the foundation period are presented, as well as the people who made this organization possible, and the state of psychology on the American continent at that time. Secondly, the most important activities that the Interamerican Society of Psychology has developed during its 60 years are mentioned, such as the publication of books and scientific journals, the creation of several task forces and the Interamerican Congresses of Psychology. Basically, the purpose of this paper is to review the history of the Interamerican Society of Psychology through the recovery and use of various documentary sources.

  6. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes)

    PubMed Central

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-01-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum ‘saw’ in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the ‘saw-teeth’ were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the ‘many-for-one’ replacement characteristic of elasmobranch oral dentitions. PMID:26473044

  7. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes).

    PubMed

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-09-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum 'saw' in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the 'saw-teeth' were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the 'many-for-one' replacement characteristic of elasmobranch oral dentitions.

  8. Origin and structural development of the LaSalle Arch, Louisiana

    SciTech Connect

    Lawless, P.N. )

    1990-05-01

    The LaSalle arch is a basement high separating the Louisiana and Mississippi interior salt basins. Using reflection seismic data, an area located on the southern end of the LaSalle arch was shown to be composed of relict Paleozoic continental crust that was left behind and partially rifted during the breakup of Pangea during the Triassic. Rifting preferentially occurred to the north of a Paleozoic thrust fault nose, and crustal extension took place in a northeast-southwest direction. The LaSalle arch, as seen in post-Triassic stratigraphy, formed by a two-part process. The western limb developed syndepositionally due to differential subsidence, and the eastern limb developed due to relative regional tilting to the east after deposition of the Claibornian Sparta Formation. The LaSalle arch acted as only a minor impediment to sediment transport with a very low relief except during the Tayloran Stage of the Upper Cretaceous. A single truncational unconformity in post-Triassic stratigraphy is present in the Taylora Demopolis Formation, indicating a period of relatively major uplift by the LaSalle arch. This contrast, with the Sabine arch in eastern Texas; the Sabine arch experienced uplift during the Eagle Fordian and Sabinian stages. A recently proposed hypothesis calling for overthrusting in the Western Cordillera as the mechanism for uplift on the Sabine arch cannot explain movement of the LaSalle arch because horizontal stress would predict synchronous uplift of basement highs. A more satisfactory uplift mechanism calls upon lateral heat flow from the mantle as the driving force for uplift.

  9. Development of hybrid particle tracking algorithms and their applications in airflow measurement within an aircraft cabin mock-up

    NASA Astrophysics Data System (ADS)

    Yan, Wei

    Obtaining reliable experimental airflow data within an indoor environment is a challenging task and critical in studying and solving indoor air quality problems. The Hybrid Particle Tracking Velocimetry (HPTV) system is aimed at fulfilling this need. It was developed based on existing Particle Tracking Velocimety (PTV) and Volumetric Particle Tracking Velocimetry (VPTV) techniques. The HPTV system requires three charge-coupled device (CCD) cameras to view the illuminated flow field and capture the trajectories of the seeded particles. By adopting the hybrid spatial matching and object tracking algorithms, this system can acquire the 3-Dimensional velocity components within a large volume with relatively high spatial and temporal resolution. Synthetic images were employed to validate the performance of three components of the system: image processing, camera calibration and 3D velocity reconstruction. These three components are also the main error sources. The accuracy of the whole algorithm was analyzed and discussed through a back projection approach. The results showed that the algorithms performed effectively and accurately. The reconstructed 3D trajectories and streaks agreed well with the simulated streamline of the particles. As an overall testing and application of the system, HPTV was applied to measure the airflow pattern within a full-scale, five-row section of a Boeing 767-300 aircraft cabin mockup. A complete experimental procedure was developed and strictly followed throughout the experiment. Both global flow field at the whole cabin scale and the local flow field at the breathing zone of one passenger were studied. Each test case was also simulated numerically using a commercial computational fluid dynamic (CFD) package. Through comparison between the results from the numerical simulation and the experimental measurement, the potential model validation capability of the system was demonstrated. Possible reasons explaining the difference between

  10. Hybrid Algorithms for Fuzzy Reverse Supply Chain Network Design

    PubMed Central

    Che, Z. H.; Chiang, Tzu-An; Kuo, Y. C.

    2014-01-01

    In consideration of capacity constraints, fuzzy defect ratio, and fuzzy transport loss ratio, this paper attempted to establish an optimized decision model for production planning and distribution of a multiphase, multiproduct reverse supply chain, which addresses defects returned to original manufacturers, and in addition, develops hybrid algorithms such as Particle Swarm Optimization-Genetic Algorithm (PSO-GA), Genetic Algorithm-Simulated Annealing (GA-SA), and Particle Swarm Optimization-Simulated Annealing (PSO-SA) for solving the optimized model. During a case study of a multi-phase, multi-product reverse supply chain network, this paper explained the suitability of the optimized decision model and the applicability of the algorithms. Finally, the hybrid algorithms showed excellent solving capability when compared with original GA and PSO methods. PMID:24892057

  11. Hybrid algorithms for fuzzy reverse supply chain network design.

    PubMed

    Che, Z H; Chiang, Tzu-An; Kuo, Y C; Cui, Zhihua

    2014-01-01

    In consideration of capacity constraints, fuzzy defect ratio, and fuzzy transport loss ratio, this paper attempted to establish an optimized decision model for production planning and distribution of a multiphase, multiproduct reverse supply chain, which addresses defects returned to original manufacturers, and in addition, develops hybrid algorithms such as Particle Swarm Optimization-Genetic Algorithm (PSO-GA), Genetic Algorithm-Simulated Annealing (GA-SA), and Particle Swarm Optimization-Simulated Annealing (PSO-SA) for solving the optimized model. During a case study of a multi-phase, multi-product reverse supply chain network, this paper explained the suitability of the optimized decision model and the applicability of the algorithms. Finally, the hybrid algorithms showed excellent solving capability when compared with original GA and PSO methods. PMID:24892057

  12. Hybrid algorithms for fuzzy reverse supply chain network design.

    PubMed

    Che, Z H; Chiang, Tzu-An; Kuo, Y C; Cui, Zhihua

    2014-01-01

    In consideration of capacity constraints, fuzzy defect ratio, and fuzzy transport loss ratio, this paper attempted to establish an optimized decision model for production planning and distribution of a multiphase, multiproduct reverse supply chain, which addresses defects returned to original manufacturers, and in addition, develops hybrid algorithms such as Particle Swarm Optimization-Genetic Algorithm (PSO-GA), Genetic Algorithm-Simulated Annealing (GA-SA), and Particle Swarm Optimization-Simulated Annealing (PSO-SA) for solving the optimized model. During a case study of a multi-phase, multi-product reverse supply chain network, this paper explained the suitability of the optimized decision model and the applicability of the algorithms. Finally, the hybrid algorithms showed excellent solving capability when compared with original GA and PSO methods.

  13. On the Late Development and Possible Astronomical Origin of the Gyroscope

    NASA Astrophysics Data System (ADS)

    Brecher, Kenneth

    2013-01-01

    The invention of the gyroscope is usually attributed to the French physicist Jean-Bernard-Leon Foucault in the year 1852. He certainly created the word and also used his gyroscope to demonstrate the rotation of the Earth. However, the gyroscope was actually invented around 1812 by the German scientist Johann Bohnenberger who called his device simply the “machine”. Bohnenberger was a professor of astronomy and mathematics and published a book about astronomy in 1811. Several other scientists, including American physicist Walter R. Johnson (who called his apparatus the “rotascope”), independently invented the gyroscope. Each of these devices employed a central object (sphere or disc) that could spin on a shaft. This object was placed between three independent gimbals, two of which could move freely. Bohnenberger’s “machine” has much the same appearance as an armillary sphere. Those astronomical devices had been produced for at least the preceding three centuries and were widely dispersed and well known throughout Europe. They were used to display the apparent motion of celestial bodies. However, armillary spheres were used only as simulations of celestial appearances, not as actual demonstrations of physical phenomena. It is not known if the inertial properties of armillary spheres (and also of terrestrial and celestial globes) had been studied before about 1800. Nonetheless, as a matter of practice, gimbal systems similar to those found in gyroscopes were used on ships to level oil lamps at least as early as the sixteenth century AD. And the ideas behind armillary spheres date back at least a millennium before that. So why did the invention of the gyroscope in its modern form take such a long time when the individual underlying components had been around and utilized for some two millennia? Perhaps because the understanding of angular momentum, including its conservation, was not developed until the start of the 19th century and also because the

  14. MinUrals: Mineral resources of the Urals -- origin, development, and environmental impact

    NASA Astrophysics Data System (ADS)

    Leistel, J. M.; Minurals Team

    2003-04-01

    The MinUrals project (supported by the European Commission under the 5th F.P.- INCO2 - contract ICA2-CT-2000-10011) is focusing on the South Urals mining sector, in order to improve local socio-economic conditions, through: 1) The reinterpretation of the geodynamics of South Urals and of the different types of ore deposits and the development of tools for mineral exploration (new geophysical and geochemical technology). The convergence setting and the formation of arc, fore-arc and back-arc systems explain the volcano-sedimentary and structural features. This geodynamic setting largely controls the distribution and characteristics of the different types of mineralisation; 2) The evaluation of local mining-related risks to the environment, with a development of methodologies for assessing and reducing the environmental impact and localizing areas of high metal potential/low environmental constraints. Three pilote sites were investigated: Sibay and Uchaly (with mining installations), and Karabash (with mining installations and smelter); 3) The implementation of a Geographical Information System taking into account the mineral potential and the environmental constraints that, through data ranking and combining the key parameters of the areas with high metal potential and environmental constraints, will enable the production of a Mineral Potential and Environmental Constraints Map of the South Urals; 4) The elaboration of recommendations for a suitable environmentally-aware mining-industry legislation, based on a comparison with the European legislation, to be adressed to the Commission on the demarcation of powers and subjects between the federal government, governments of the subjects of the Russian Federation and local authorities. More information can be found on the project web sites [http://minurals.brgm.fr] or [http://www.nhm.ac.uk/mineralogy/minurals/minurals.htm] or [http://www.anrb.ru/geol/MinUrals] or [http://minurals.ilmeny.ac.ru] MinUrals Team (*): Aug

  15. Development of optical design algorithms on the base of the exact (all orders) geometrical aberration theory

    NASA Astrophysics Data System (ADS)

    Hristov, Boian A.

    2011-10-01

    The process of optical design today is both an art and a science mainly due to the lack of exact and suitable aberration theory. In this paper we propose an exact (without any approximations) analytical aberration theory. It describes exactly the relations between the on-axis image aberrations and on-axis object aberrations via so called relative parameters, real aperture incidence angles, real aperture slope angles, refraction indexes and object distance. The image field aberrations (distortion, astigmatism, tangential curvature, sagittal curvature and field curvature) are described in a mathematically exact way by means of relative parameters, real incidence angles and slope angles of the chief rays, refraction indexes, object distance and corresponding object aberrations. For the image tangential coma and image sagittal coma we propose differential formulae. To verify the correction of every single aberration we use the commercial program OSLO. The differences between our and OSLO results for each aberration (except for the tangential and sagittal coma) are less than 1x10-8 mm. In addition we propose some exact aberration's correction algorithms for a very distant object and variety of constructive design solutions which confirm the truth of the proposed theory.

  16. Development and applications of various optimization algorithms for diesel engine combustion and emissions optimization

    NASA Astrophysics Data System (ADS)

    Ogren, Ryan M.

    For this work, Hybrid PSO-GA and Artificial Bee Colony Optimization (ABC) algorithms are applied to the optimization of experimental diesel engine performance, to meet Environmental Protection Agency, off-road, diesel engine standards. This work is the first to apply ABC optimization to experimental engine testing. All trials were conducted at partial load on a four-cylinder, turbocharged, John Deere engine using neat-Biodiesel for PSO-GA and regular pump diesel for ABC. Key variables were altered throughout the experiments, including, fuel pressure, intake gas temperature, exhaust gas recirculation flow, fuel injection quantity for two injections, pilot injection timing and main injection timing. Both forms of optimization proved effective for optimizing engine operation. The PSO-GA hybrid was able to find a superior solution to that of ABC within fewer engine runs. Both solutions call for high exhaust gas recirculation to reduce oxide of nitrogen (NOx) emissions while also moving pilot and main fuel injections to near top dead center for improved tradeoffs between NOx and particulate matter.

  17. The Development of a Factorizable Multigrid Algorithm for Subsonic and Transonic Flow

    NASA Technical Reports Server (NTRS)

    Roberts, Thomas W.

    2001-01-01

    The factorizable discretization of Sidilkover for the compressible Euler equations previously demonstrated for channel flows has been extended to external flows.The dissipation of the original scheme has been modified to maintain stability for moderately stretched grids. The discrete equations are solved by symmetric collective Gauss-Seidel relaxation and FAS multigrid. Unlike the earlier work ordering the grid vertices in the flow direction has been found to be unnecessary. Solutions for essential incompressible flow (Mach 0.01) and supercritical flows have obtained for a Karman-Trefftz airfoil with it conformally mapped grid,as well as a NACA 0012 on an algebraically generated grid. The current work demonstrates nearly 0(n) convergence for subsonic and slightly transonic flows.

  18. Multiple shooting algorithms for jump-discontinuous problems in optimal control and estimation

    NASA Technical Reports Server (NTRS)

    Mook, D. J.; Lew, Jiann-Shiun

    1991-01-01

    Multiple shooting algorithms are developed for jump-discontinuous two-point boundary value problems arising in optimal control and optimal estimation. Examples illustrating the origin of such problems are given to motivate the