Science.gov

Sample records for algorithm developed earlier

  1. Developing Scoring Algorithms (Earlier Methods)

    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.

  2. Algorithms for Developing Test Questions from Sentences in Instructional Materials: An Extension of an Earlier Study.

    ERIC Educational Resources Information Center

    Roid, Gale H.; And Others

    An earlier study was extended and replicated to examine the feasibility of generating multiple-choice test questions by transforming sentences from prose instructional material. In the first study, a computer-based algorithm was used to analyze prose subject matter and to identify high-information words. Sentences containing selected words were…

  3. Algorithms for Developing Test Questions from Sentences in Instructional Materials: an Extension of an Earlier Study

    DTIC Science & Technology

    1980-01-01

    8217.> age were developed using the following procedure; 1. The selected mat -rial was computer-analyzed to identify high information words—those that an...frequencies (keyword and rare singletons), (4) the two foil types (writer’s choice and algorithmic), and (5) the two test occasions (pi etest and

  4. 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.

  5. 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.

  6. Secular trend of earlier onset and decelerated development of third molars: evidence from Croatia.

    PubMed

    Sasso, Anja; Legovic, Mario; Mady Maricic, Barbara; Pavlic, Andrej; Spalj, Stjepan

    2015-04-01

    The purpose of this study was to evaluate the influence of the secular trend on development of third molars in 30 years period in Littoral region of Croatia. A total of 1103 panoramic radiographs of subjects aged from 6 to 18 years were analysed. First group comprised 531 panoramic radiographs (258 girls) taken from year period 1977 till 1979 and second group 572 radiographs (325 girls) taken from year period 2007 till 2009. Demirjian's method was used to determine the developmental stage of third molars. A secular trend in 30 years period was observed as earlier onset of third molars development in boys (6 months on average maxillary and 11 months mandibular) and girls (6 months for maxillary and 4 months for mandibular). Now-a-days, an increase in mineralisation for one Demirjian stage occurs at a slower pace of 5.2 months in boys and 3.4 in girls in maxilla and 2.3 or 2 months in mandible for boys and girls, respectively. The study showed a secular trend present as earlier onset but decelerated development of third molars in both genders and both jaws.

  7. 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.

  8. Motivation before meaning: motivational information encoded in meerkat alarm calls develops earlier than referential information.

    PubMed

    Hollén, Linda I; Manser, Marta B

    2007-06-01

    In contrast to historical assumptions about the affective nature of animal vocalizations, it is now clear that many vertebrates are capable of producing specific alarm calls in response to different predators, calls that provide information that goes beyond the motivational state of a caller. However, although these calls function referentially, it does not mean that they are devoid of motivational content. Studies on meerkats (Suricata suricatta) directly support this conclusion. The acoustic structure of their alarm calls simultaneously encodes information that is both motivational (level of urgency) and referential (predator specific). In this study, we investigated whether alarm calls of young meerkats undergo developmental modification and whether the motivational or the referential aspect of calls changes more over time. We found that, based on their acoustic structure, calls of young showed a high correct assignment to low- and high-urgency contexts but, in contrast to adults, low assignment to specific predator types. However, the discrimination among predator types was better in high-urgency than in low-urgency contexts. Our results suggest that acoustic features related to level of urgency are expressed earlier than those related to predator-specific information and may support the idea that referential calls evolve from motivational signals.

  9. Source Book of Projects, Science Education Development and Research. Fiscal Year 1981, with References to Earlier Years.

    ERIC Educational Resources Information Center

    National Science Foundation, Washington, DC. Directorate for Science and Engineering Education.

    This publication describes awards made in the National Science Foundation's Division of Science Education Development and Research in FY 1981, FY 1980, and in earlier years. Two indices are contained in the first section. The first index is a rotated title index to every award in the publication. Every significant word in each title is an entry…

  10. Source Book of Projects, Science Education Development and Research. Fiscal Year 1980, with References to Earlier Years.

    ERIC Educational Resources Information Center

    National Science Foundation, Washington, DC. Directorate for Science and Engineering Education.

    This publication describes awards made in the National Science Foundation's Division of Science Education Development and Research in FY 1980, FY 1979, and in earlier years. Two indices are contained in the first section. The first index is a rotated title index to every award in the publication. Every significant word in each title is an entry…

  11. 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.

  12. 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.

  13. 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.

  14. Algorithms for Software Development

    NASA Technical Reports Server (NTRS)

    Tausworthe, R. C.

    1985-01-01

    Management aid makes changes obvious. One key element in scheme for software development control is check summing. If check sum for given line in source file is different from previous version, it is evident change has been made. Subsequent editing of file creates new lines, deletes old ones, modifies characters, moves lines, or copies (reuse) existing lines. Combination of three elements of line code permits all transactions to be detected.

  15. 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.

  16. Advanced seasonal reproductive development in a male urban bird is reflected in earlier plasma luteinizing hormone rise but not energetic status.

    PubMed

    Davies, Scott; Behbahaninia, Hirbod; Giraudeau, Mathieu; Meddle, Simone L; Waites, Kyle; Deviche, Pierre

    2015-12-01

    Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees.

  17. 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.

  18. CD99 polymorphisms significantly influence the probability to develop Ewing sarcoma in earlier age and patient disease progression

    PubMed Central

    Martinelli, Marcella; Parra, Alessandro; Scapoli, Luca; Sanctis, Paola De; Chiadini, Valentina; Hattinger, Claudia; Picci, Piero

    2016-01-01

    Ewing sarcoma (EWS), the second most common primary bone tumor in pediatric age, is known for its paucity of recurrent somatic abnormalities. Apart from the chimeric oncoprotein that derives from the fusion of EWS and FLI genes, recent genome-wide association studies have identified susceptibility variants near the EGR2 gene that regulate DNA binding of EWS-FLI. However, to induce transformation, EWS-FLI requires the presence of additional molecular events, including the expression of CD99, a cell surface molecule with critical relevance for the pathogenesis of EWS. High expression of CD99 is a common and distinctive feature of EWS cells, and it has largely been used for the differential diagnosis of the disease. The present study first links CD99 germline genetic variants to the susceptibility of EWS development and its progression. In particular, a panel of 25 single nucleotide polymorphisms has been genotyped in a case-control study. The CD99 rs311059 T variant was found to be significantly associated [P value = 0.0029; ORhet = 3.9 (95% CI 1.5-9.8) and ORhom = 5.3 (95% CI 1.2-23.7)] with EWS onset in patients less than 14 years old, while the CD99 rs312257-T was observed to be associated [P value = 0.0265; ORhet = 3.5 (95% CI 1.3-9.9)] with a reduced risk of relapse. Besides confirming the importance of CD99, our findings indicate that polymorphic variations in this gene may affect either development or progression of EWS, leading to further understanding of this cancer and development of better diagnostics/prognostics for children and adolescents with this devastating disease. PMID:27792997

  19. High atmospheric temperatures and ‘ambient incubation’ drive embryonic development and lead to earlier hatching in a passerine bird

    PubMed Central

    Griffith, Simon C.; Mainwaring, Mark C.; Sorato, Enrico; Beckmann, Christa

    2016-01-01

    Tropical and subtropical species typically experience relatively high atmospheric temperatures during reproduction, and are subject to climate-related challenges that are largely unexplored, relative to more extensive work conducted in temperate regions. We studied the effects of high atmospheric and nest temperatures during reproduction in the zebra finch. We characterized the temperature within nests in a subtropical population of this species in relation to atmospheric temperature. Temperatures within nests frequently exceeded the level at which embryo’s develop optimally, even in the absence of parental incubation. We experimentally manipulated internal nest temperature to demonstrate that an average difference of 6°C in the nest temperature during the laying period reduced hatching time by an average of 3% of the total incubation time, owing to ‘ambient incubation’. Given the avian constraint of laying a single egg per day, the first eggs of a clutch are subject to prolonged effects of nest temperature relative to later laid eggs, potentially increasing hatching asynchrony. While birds may ameliorate the negative effects of ambient incubation on embryonic development by varying the location and design of their nests, high atmospheric temperatures are likely to constitute an important selective force on avian reproductive behaviour and physiology in subtropical and tropical regions, particularly in the light of predicted climate change that in many areas is leading to a higher frequency of hot days during the periods when birds breed. PMID:26998315

  20. Principles for Developing Algorithmic Instruction.

    DTIC Science & Technology

    1978-12-01

    information-processing theories to test their applicability with instruction directed by learning algorithms. A version of a logical, or familiar, and a...intent of our research was to borrow~ from information-processing theory factors which are known to affect learning in a predictable manner and to apply... learning studies where processing theories are tested by minute performance or latency differences. -~ It is not surprising that differences are seldom found

  1. 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.

  2. An earlier de motu cordis.

    PubMed Central

    Daly, Walter J.

    2004-01-01

    Thirteenth century medical science, like medieval scholarship in general, was directed at reconciliation of Greek philosophy/science with prevailing medieval theology and philosophy. Peter of Spain [later Pope John XXI] was the leading medical scholar of his time. Peter wrote a long book on the soul. Imbedded in it was a chapter on the motion of the heart. Peter's De Motu was based on his own medical experience and Galen's De Usu Partium and De Usu Respirationis and De Usu Pulsuum. This earlier De Motu defines a point on the continuum of intellectual development leading to us and into the future. Thirteenth century scholarship relied on past authority to a degree that continues to puzzle and beg explanation. Images Fig. 1 PMID:17060956

  3. 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.

  4. 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.

  5. Further development of an improved altimeter wind speed algorithm

    NASA Technical Reports Server (NTRS)

    Chelton, Dudley B.; Wentz, Frank J.

    1986-01-01

    A previous altimeter wind speed retrieval algorithm was developed on the basis of wind speeds in the limited range from about 4 to 14 m/s. In this paper, a new approach which gives a wind speed model function applicable over the range 0 to 21 m/s is used. The method is based on comparing 50 km along-track averages of the altimeter normalized radar cross section measurements with neighboring off-nadir scatterometer wind speed measurements. The scatterometer winds are constructed from 100 km binned measurements of radar cross section and are located approximately 200 km from the satellite subtrack. The new model function agrees very well with earlier versions up to wind speeds of 14 m/s, but differs significantly at higher wind speeds. The relevance of these results to the Geosat altimeter launched in March 1985 is discussed.

  6. Algorithm development for hyperspectral anomaly detection

    NASA Astrophysics Data System (ADS)

    Rosario, Dalton S.

    2008-10-01

    This dissertation proposes and evaluates a novel anomaly detection algorithm suite for ground-to-ground, or air-to-ground, applications requiring automatic target detection using hyperspectral (HS) data. Targets are manmade objects in natural background clutter under unknown illumination and atmospheric conditions. The use of statistical models herein is purely for motivation of particular formulas for calculating anomaly output surfaces. In particular, formulas from semiparametrics are utilized to obtain novel forms for output surfaces, and alternative scoring algorithms are proposed to calculate output surfaces that are comparable to those of semiparametrics. Evaluation uses both simulated data and real HS data from a joint data collection effort between the Army Research Laboratory and the Army Armament Research Development & Engineering Center. A data transformation method is presented for use by the two-sample data structure univariate semiparametric and nonparametric scoring algorithms, such that, the two-sample data are mapped from their original multivariate space to an univariate domain, where the statistical power of the univariate scoring algorithms is shown to be improved relative to existing multivariate scoring algorithms testing the same two-sample data. An exhaustive simulation experimental study is conducted to assess the performance of different HS anomaly detection techniques, where the null and alternative hypotheses are completely specified, including all parameters, using multivariate normal and mixtures of multivariate normal distributions. Finally, for ground-to-ground anomaly detection applications, where the unknown scales of targets add to the problem complexity, a novel global anomaly detection algorithm suite is introduced, featuring autonomous partial random sampling (PRS) of the data cube. The PRS method is proposed to automatically sample the unknown background clutter in the test HS imagery, and by repeating multiple times this

  7. 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.

  8. Development of Improved Algorithms and Multiscale Modeling Capability with SUNTANS

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Development of Improved Algorithms and Multiscale...a wide range of scales through use of accurate numerical methods and high- performance computational algorithms . The tool will be applied to study...dissipation. OBJECTIVES The primary objective is to enhance the capabilities of the SUNTANS model through development of algorithms to study

  9. 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).

  10. Comparisons between in vitro whole cell imaging and in vivo zebrafish-based approaches for identifying potential human hepatotoxicants earlier in pharmaceutical development.

    PubMed

    Hill, Adrian; Mesens, Natalie; Steemans, Margino; Xu, Jinghai James; Aleo, Michael D

    2012-02-01

    Drug-induced liver injury (DILI) is a major cause of attrition during both the early and later stages of the drug development and marketing process. Reducing or eliminating drug-induced severe liver injury, especially those that lead to liver transplants or death, would be tremendously beneficial for patients. Therefore, developing new pharmaceuticals that have the highest margins and attributes of hepatic safety would be a great accomplishment. Given the current low productivity of pharmaceutical companies and the high costs of bringing new medicines to market, any early screening assay(s) to identify and eliminate pharmaceuticals with the potential to cause severe liver injury in humans would be of economic value as well. The present review discusses the background, proof-of-concept, and validation studies associated with high-content screening (HCS) by two major pharmaceutical companies (Pfizer Inc and Jansen Pharmaceutical Companies of Johnson & Johnson) for detecting compounds with the potential to cause human DILI. These HCS assays use fluorescent-based markers of cell injury in either human hepatocytes or HepG2 cells. In collaboration with Evotec, an independent contract lab, these two companies also independently evaluated larval zebrafish as an early-stage in vivo screen for hepatotoxicity in independently conducted, blinded assessments. Details about this model species, the need for bioanalysis, and, specifically, the outcome of the phenotypic-based zebrafish screens are presented. Comparing outcomes in zebrafish against both HCS assays suggests an enhanced detection for hepatotoxicants of most DILI concern when used in combination with each other, based on the U.S. Food and Drug Administration DILI classification list.

  11. New developments in astrodynamics algorithms for autonomous rendezvous

    NASA Technical Reports Server (NTRS)

    Klumpp, Allan R.

    1991-01-01

    A the core of any autonomous rendezvous guidance system must be two algorithms for solving Lambert's and Kepler's problems, the two fundamental problems in classical astrodynamics. Lambert's problem is to determine the trajectory connecting specified initial and terminal position vectors in a specified transfer time. The solution is the initial and terminal velocity vectors. Kepler's problem is to determine the trajectory that stems from a given initial state (position and velocity). The solution is the state of an earlier or later specified time. To be suitable for flight software, astrodynamics algorithms must be totally reliable, compact, and fast. Although solving Lambert's and Kepler's problems has challenged some of the world's finest minds for over two centuries, only in the last year have algorithms appeared that satisfy all three requirements just stated. This paper presents an evaluation of the most highly regarded Lambert and Kepler algorithms.

  12. 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.

  13. 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.

  14. 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.

  15. SSME structural computer program development: BOPACE theoretical manual, addendum. [algorithms

    NASA Technical Reports Server (NTRS)

    1975-01-01

    An algorithm developed and incorporated into BOPACE for improving the convergence and accuracy of the inelastic stress-strain calculations is discussed. The implementation of separation of strains in the residual-force iterative procedure is defined. The elastic-plastic quantities used in the strain-space algorithm are defined and compared with previous quantities.

  16. Development and application of multispectral algorithms for defect apple inspection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research developed and evaluated the multispectral algorithm derived from hyperspectral line-scan imaging system which equipped with an electron-multiplying-charge-coupled-device camera and an imaging spectrograph for the detection of defect Red Delicious apples. The algorithm utilized the fluo...

  17. [Why and how to treat psychosis earlier?

    PubMed

    Laprevote, Vincent; Heitz, Ulrike; Di Patrizio, Paolo; Studerus, Erich; Ligier, Fabienne; Schwitzer, Thomas; Schwan, Raymund; Riecher-Rössler, Anita

    2016-11-01

    Chronic psychosis, as for instance schizophrenia, usually begins in young adulthood and may cause severe disability. It causes a mean loss of life expectancy of 22 years. Actual models of psychosis do not trace the beginning of psychosis to the first franc psychotic episode only, but to earlier symptoms. In a classical health system only considering the first psychotic episode, the mean duration of untreated illness (DUI) can last several years. Yet this DUI has a direct impact on the prognosis of the disease. Actual international recommendations prescribe to early detect and treat at risk mental states of psychosis, thus reducing DUI. Such an attitude also helps the patient to integrate care in a moment where she/he is fully in condition to consent and to adhere. Generalist practitioners are crucial actors of early detection. We describe here simple and standardized tools helping early detection of high-risk mental states of psychosis in primary care and the appropriate attitude to do it properly. Numerous countries have developed early detection and treatment centers for psychosis. It has been established that such interventions clearly decrease the risk of transition towards chronic psychosis and improve the prognosis. These recent data about early detection and intervention in psychosis are a major step forward in psychiatry practice. It is now necessary to largely develop such actions in France.

  18. 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.

  19. Can Breath Test Detect Stomach Cancers Earlier?

    MedlinePlus

    ... news/fullstory_163342.html Can Breath Test Detect Stomach Cancers Earlier? New technology may also spot esophageal ... 2017 (HealthDay News) -- A breath test to detect stomach and esophageal cancers shows promise, researchers say. The ...

  20. 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.

  1. Development of multigrid algorithms for problems from fluid dynamics

    NASA Astrophysics Data System (ADS)

    Becker, K.; Trottenberg, U.

    Multigrid algorithms are developed to demonstrate multigrid technique efficiency for complicated fluid dynamics problems regarding error reduction and discretization accuracy. Subsonic potential 2-D flow around a profile is studied as well as rotation-symmetric flow in a slot between two rotating spheres and the flow in the combustion chamber of Otto engines. The study of the 2-D subsonic potential flow around a profile with the multigrid algorithm is discussed.

  2. Algorithmic Basics of Search Engine Development

    NASA Astrophysics Data System (ADS)

    Tregubov, A. A.; Kononova, T. S.

    The basics of search engines development are reviewed in this report. A structure of search engine as a part of an electronic library is offered. Methods of smart search of relevant information based on multi-agent systems and document processing methods are reviewed in the report. Analysis of major problems of processing, indexing and relevance evaluation is carried out. Statistical indexing, algebraic relevance evaluation and linguistic automaton construction for effective document processing and understanding are considered.

  3. 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.

  4. JPSS Cryosphere Algorithms: Integration and Testing in Algorithm Development Library (ADL)

    NASA Astrophysics Data System (ADS)

    Tsidulko, M.; Mahoney, R. L.; Meade, P.; Baldwin, D.; Tschudi, M. A.; Das, B.; Mikles, V. J.; Chen, W.; Tang, Y.; Sprietzer, K.; Zhao, Y.; Wolf, W.; Key, J.

    2014-12-01

    JPSS is a next generation satellite system that is planned to be launched in 2017. The satellites will carry a suite of sensors that are already on board the Suomi National Polar-orbiting Partnership (S-NPP) satellite. The NOAA/NESDIS/STAR Algorithm Integration Team (AIT) works within the Algorithm Development Library (ADL) framework which mimics the operational JPSS Interface Data Processing Segment (IDPS). The AIT contributes in development, integration and testing of scientific algorithms employed in the IDPS. This presentation discusses cryosphere related activities performed in ADL. The addition of a new ancillary data set - NOAA Global Multisensor Automated Snow/Ice data (GMASI) - with ADL code modifications is described. Preliminary GMASI impact on the gridded Snow/Ice product is estimated. Several modifications to the Ice Age algorithm that demonstrates mis-classification of ice type for certain areas/time periods are tested in the ADL. Sensitivity runs for day time, night time and terminator zone are performed and presented. Comparisons between the original and modified versions of the Ice Age algorithm are also presented.

  5. 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.

  6. Tactical weapons algorithm development for unitary and fused systems

    NASA Astrophysics Data System (ADS)

    Talele, Sunjay E.; Watson, John S.; Williams, Bradford D.; Amphay, Sengvieng A.

    1996-06-01

    A much needed capability in today's tactical Air Force is weapons systems capable of precision guidance in all weather conditions against targets in high clutter backgrounds. To achieve this capability, the Armament Directorate of Wright Laboratory, WL/MN, has been exploring various seeker technologies, including multi-sensor fusion, that may yield cost effective systems capable of operating under these conditions. A critical component of these seeker systems is their autonomous acquisition and tracking algorithms. It is these algorithms which will enable the autonomous operation of the weapons systems in the battlefield. In the past, a majority of the tactical weapon algorithms were developed in a manner which resulted in codes that were not releasable to the community, either because they were considered company proprietary or competition sensitive. As a result, the knowledge gained from these efforts was not transitioning through the technical community, thereby inhibiting the evolution of their development. In order to overcome this limitation, WL/MN has embarked upon a program to develop non-proprietary multi-sensor acquisition and tracking algorithms. To facilitate this development, a testbed has been constructed consisting of the Irma signature prediction model, data analysis workstations, and the modular algorithm concept evaluation tool (MACET) algorithm. All three of these components have been enhanced to accommodate both multi-spectral sensor fusion systems and the there dimensional signal processing techniques characteristic of ladar. MACET is a graphical interface driven system for rapid prototyping and evaluation of both unitary and fused sensor algorithms. This paper describes the MACET system and specifically elaborates on the three-dimensional capabilities recently incorporated into it.

  7. 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.

  8. 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.

  9. 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.

  10. 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…

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. Earlier snowmelt and warming lead to earlier but not necessarily more plant growth

    PubMed Central

    Livensperger, Carolyn; Steltzer, Heidi; Darrouzet-Nardi, Anthony; Sullivan, Patrick F.; Wallenstein, Matthew; Weintraub, Michael N.

    2016-01-01

    Climate change over the past ∼50 years has resulted in earlier occurrence of plant life-cycle events for many species. Across temperate, boreal and polar latitudes, earlier seasonal warming is considered the key mechanism leading to earlier leaf expansion and growth. Yet, in seasonally snow-covered ecosystems, the timing of spring plant growth may also be cued by snowmelt, which may occur earlier in a warmer climate. Multiple environmental cues protect plants from growing too early, but to understand how climate change will alter the timing and magnitude of plant growth, experiments need to independently manipulate temperature and snowmelt. Here, we demonstrate that altered seasonality through experimental warming and earlier snowmelt led to earlier plant growth, but the aboveground production response varied among plant functional groups. Earlier snowmelt without warming led to early leaf emergence, but often slowed the rate of leaf expansion and had limited effects on aboveground production. Experimental warming alone had small and inconsistent effects on aboveground phenology, while the effect of the combined treatment resembled that of early snowmelt alone. Experimental warming led to greater aboveground production among the graminoids, limited changes among deciduous shrubs and decreased production in one of the dominant evergreen shrubs. As a result, we predict that early onset of the growing season may favour early growing plant species, even those that do not shift the timing of leaf expansion. PMID:27075181

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Development of clustering algorithms for Compressed Baryonic Matter experiment

    NASA Astrophysics Data System (ADS)

    Kozlov, G. E.; Ivanov, V. V.; Lebedev, A. A.; Vassiliev, Yu. O.

    2015-05-01

    A clustering problem for the coordinate detectors in the Compressed Baryonic Matter (CBM) experiment is discussed. Because of the high interaction rate and huge datasets to be dealt with, clustering algorithms are required to be fast and efficient and capable of processing events with high track multiplicity. At present there are two different approaches to the problem. In the first one each fired pad bears information about its charge, while in the second one a pad can or cannot be fired, thus rendering the separation of overlapping clusters a difficult task. To deal with the latter, two different clustering algorithms were developed, integrated into the CBMROOT software environment, and tested with various types of simulated events. Both of them are found to be highly efficient and accurate.

  5. 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.

  6. Development of algorithm for single axis sun tracking system

    NASA Astrophysics Data System (ADS)

    Yi, Lim Zi; Singh, Balbir Singh Mahinder; Ching, Dennis Ling Chuan; Jin, Calvin Low Eu

    2016-11-01

    The output power from a solar panel depends on the amount of sunlight that is intercepted by the photovoltaic (PV) solar panel. The value of solar irradiance varies due to the change of position of sun and the local meteorological conditions. This causes the output power of a PV based solar electricity generating system (SEGS) to fluctuate as well. In this paper, the focus is on the integration of solar tracking system with performance analyzer system through the development of an algorithm for optimizing the performance of SEGS. The proposed algorithm displays real-time processed data that would enable users to understand the trend of the SEGS output for maintenance prediction and optimization purposes.

  7. 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.

  8. Can prion disease suspicion be supported earlier?

    PubMed Central

    Medina, Zaira; Balaguer, Rainier Rodriguez; Calleja, Jesus Higuera

    2011-01-01

    The subacute spongiform encephalopathies are prion diseases characterized by acute and rapid neurodegeneration that lead to the death of the patient within months to a few years. The epidemiology of CJD is complicated and the frequency in Mexico is unknown. We aim to describe the cases of prion disease in Mexico. Consecutive patients who met the diagnostic criteria by the WHO were enrolled. We describe 26 patients with clinical manifestations, imaging and laboratory studies compatible with prion disease. The mean age at onset was 52 years old. The main clinical manifestations were cognitive alterations (69%) followed by extrapyramidal movements (50%), abnormal cerebellar function (46%), behavioral alterations (46%), myoclonus (46%) and mood depression (23%), among other features. Half of the patients progressed rapidly to a state of akinetic mutism (53%). Only 2 (7.6%) patients had a family history of a similar disease. Time interval between onset and diagnosis varied between 71 days to 24 months, with a median of 6 months. The classical bilateral basal ganglia hyperintensities were present in the very early stage of the disease. Protein 14-3-3 immuneassay in the CSF was positive in all measured cases. Bilateral basal ganglia hyperintensities was the most important early finding, while protein 14-3-3 was a late finding and the results were usually obtained after the patient was discharged. Around 1.5 cases of CJD cases per year are reported in our country. When suspected, MRI can support the diagnosis earlier than other studies. PMID:21869605

  9. Development of a validation algorithm for 'present on admission' flagging

    PubMed Central

    2009-01-01

    Background The use of routine hospital data for understanding patterns of adverse outcomes has been limited in the past by the fact that pre-existing and post-admission conditions have been indistinguishable. The use of a 'Present on Admission' (or POA) indicator to distinguish pre-existing or co-morbid conditions from those arising during the episode of care has been advocated in the US for many years as a tool to support quality assurance activities and improve the accuracy of risk adjustment methodologies. The USA, Australia and Canada now all assign a flag to indicate the timing of onset of diagnoses. For quality improvement purposes, it is the 'not-POA' diagnoses (that is, those acquired in hospital) that are of interest. Methods Our objective was to develop an algorithm for assessing the validity of assignment of 'not-POA' flags. We undertook expert review of the International Classification of Diseases, 10th Revision, Australian Modification (ICD-10-AM) to identify conditions that could not be plausibly hospital-acquired. The resulting computer algorithm was tested against all diagnoses flagged as complications in the Victorian (Australia) Admitted Episodes Dataset, 2005/06. Measures reported include rates of appropriate assignment of the new Australian 'Condition Onset' flag by ICD chapter, and patterns of invalid flagging. Results Of 18,418 diagnosis codes reviewed, 93.4% (n = 17,195) reflected agreement on status for flagging by at least 2 of 3 reviewers (including 64.4% unanimous agreement; Fleiss' Kappa: 0.61). In tests of the new algorithm, 96.14% of all hospital-acquired diagnosis codes flagged were found to be valid in the Victorian records analysed. A lower proportion of individual codes was judged to be acceptably flagged (76.2%), but this reflected a high proportion of codes used <5 times in the data set (789/1035 invalid codes). Conclusion An indicator variable about the timing of occurrence of diagnoses can greatly expand the use of routinely

  10. Comparison of Performance Effectiveness of Linear Control Algorithms Developed for a Simplified Ground Vehicle Suspension System

    DTIC Science & Technology

    2011-04-01

    Comparison of Performance Effectiveness of Linear Control Algorithms Developed for a Simplified Ground Vehicle Suspension System by Ross... Linear Control Algorithms Developed for a Simplified Ground Vehicle Suspension System Ross Brown Motile Robotics, Inc, research contractor at U.S... Linear Control Algorithms Developed for a Simplified Ground Vehicle Suspension System 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  11. Development of Topological Correction Algorithms for ADCP Multibeam Bathymetry Measurements

    NASA Astrophysics Data System (ADS)

    Yang, Sung-Kee; Kim, Dong-Su; Kim, Soo-Jeong; Jung, Woo-Yul

    2013-04-01

    Acoustic Doppler Current Profilers (ADCPs) are increasingly popular in the river research and management communities being primarily used for estimation of stream flows. ADCPs capabilities, however, entail additional features that are not fully explored, such as morphologic representation of river or reservoir bed based upon multi-beam depth measurements. In addition to flow velocity, ADCP measurements include river bathymetry information through the depth measurements acquired in individual 4 or 5 beams with a given oblique angle. Such sounding capability indicates that multi-beam ADCPs can be utilized as an efficient depth-sounder to be more capable than the conventional single-beam eco-sounders. The paper introduces the post-processing algorithms required to deal with raw ADCP bathymetry measurements including the following aspects: a) correcting the individual beam depths for tilt (pitch and roll); b) filtering outliers using SMART filters; d) transforming the corrected depths into geographical coordinates by UTM conversion; and, e) tag the beam detecting locations with the concurrent GPS information; f) spatial representation in a GIS package. The developed algorithms are applied for the ADCP bathymetric dataset acquired from Han-Cheon in Juju Island to validate their applicability.

  12. Development of computer algorithms for radiation treatment planning.

    PubMed

    Cunningham, J R

    1989-06-01

    As a result of an analysis of data relating tissue response to radiation absorbed dose the ICRU has recommended a target for accuracy of +/- 5 for dose delivery in radiation therapy. This is a difficult overall objective to achieve because of the many steps that make up a course of radiotherapy. The calculation of absorbed dose is only one of the steps and so to achieve an overall accuracy of better than +/- 5% the accuracy in dose calculation must be better yet. The physics behind the problem is sufficiently complicated so that no exact method of calculation has been found and consequently approximate solutions must be used. The development of computer algorithms for this task involves the search for better and better approximate solutions. To achieve the desired target of accuracy a fairly sophisticated calculation procedure must be used. Only when this is done can we hope to further improve our knowledge of the way in which tissues respond to radiation treatments.

  13. QAP collaborates in development of the sick child algorithm.

    PubMed

    1994-01-01

    Algorithms which specify procedures for proper diagnosis and treatment of common diseases have been available to primary health care services in less developed countries for the past decade. Whereas each algorithm has usually been limited to a single ailment, children often present with the need for more comprehensive assessment and treatment. Treating just one illness in these children leads to incomplete treatment or missed opportunities for preventive services. To address this problem, the World Health Organization has recently developed a Sick Child Algorithm (SCA) for children aged 2 months-5 years. In addition to specifying case management procedures for acute respiratory illness, diarrhea/dehydration, fever, otitis, and malnutrition, the SCA prompts a check of the child's immunization status. The specificity and sensitivity of this SCA were field-tested in Kenya and the Gambia. In Kenya, the Malaria Branch of the US Centers for Disease Control and Prevention tested the SCA under typical conditions in Siaya District. The Quality Assurance Project of the Center for Human Services carried out a parallel facility-based systems analysis at the request of the Malaria Branch. The assessment which took place in September-October 1993, took the form of observations of provider/patient interactions, provider interviews, and verification of supplies and equipment in 19 rural health facilities to determine how current practices compare to actions prescribed by the SCA. This will reveal the type and amount of technical support needed to achieve conformity to the SCA's clinical practice recommendations. The data will allow officials to devise the proper training programs and will predict quality improvements likely to be achieved through adoption of the SCA in terms of effective case treatment and fewer missed immunization opportunities. Preliminary analysis indicates that the primary health care delivery in Siya deviates in several significant respects from performance

  14. Body art education: the earlier, the better.

    PubMed

    Armstrong, Myrna L; Tustin, Jane; Owen, Donna C; Koch, Jerome R; Roberts, Alden E

    2014-02-01

    Using the major format identified for successful prevention and intervention work, five "W" questions: what, why, whom, where, and who, plus one: how, this article first summarizes the current body art literature. Then, educational strategies specifically regarding the topic of tattoos and body piercing are presented for school nurses. These strategies can be used to create applicable, realistic information for young students before they are faced with decisions related to body art. The school nurse might be the first and only credible source of information the students receive related to body art in an education/health environment. Curriculum emphasis is on the decision making leading up to the action, and the major purposes, rather than on the markings or jewelry associated with procurement. Reducing decisional conflict while promoting positive development in the areas of empowerment, self-esteem, and maturing can help achieve stronger informed decision making.

  15. 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.

  16. 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

  17. Spinal Epidural Abscess: A Review with Special Emphasis on Earlier Diagnosis

    PubMed Central

    Bond, Allison

    2016-01-01

    Spinal epidural abscess (SEA) is an uncommon but serious condition with significant morbidity and mortality. The prognosis of SEA is highly dependent on the timeliness of its diagnosis before neurological deficits develop. Unfortunately, often due to its nonspecific presentation, such as back pain, the diagnosis of SEA may be delayed in up to 75% of cases. Although many risk factors for SEA can be found in the published literature, their utility is limited by their frequent lack of objective evidence, numerousness, and absence in a significant proportion of cases. In this review, we call for a more discriminate evidence-based use of the term “risk factor” when discussing SEA and explore several approaches to its earlier diagnosis, including a simple algorithm based on its pathophysiology and serum C-reactive protein or erythrocyte sedimentation rate. PMID:28044125

  18. Spinal Epidural Abscess: A Review with Special Emphasis on Earlier Diagnosis.

    PubMed

    Bond, Allison; Manian, Farrin A

    2016-01-01

    Spinal epidural abscess (SEA) is an uncommon but serious condition with significant morbidity and mortality. The prognosis of SEA is highly dependent on the timeliness of its diagnosis before neurological deficits develop. Unfortunately, often due to its nonspecific presentation, such as back pain, the diagnosis of SEA may be delayed in up to 75% of cases. Although many risk factors for SEA can be found in the published literature, their utility is limited by their frequent lack of objective evidence, numerousness, and absence in a significant proportion of cases. In this review, we call for a more discriminate evidence-based use of the term "risk factor" when discussing SEA and explore several approaches to its earlier diagnosis, including a simple algorithm based on its pathophysiology and serum C-reactive protein or erythrocyte sedimentation rate.

  19. 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.

  20. 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

  1. Quantification of distention in CT colonography: development and validation of three computer algorithms.

    PubMed

    Hung, Peter W; Paik, David S; Napel, Sandy; Yee, Judy; Jeffrey, R Brooke; Steinauer-Gebauer, Andreas; Min, Juno; Jathavedam, Ashwin; Beaulieu, Christopher F

    2002-02-01

    Three bowel distention-measuring algorithms for use at computed tomographic (CT) colonography were developed, validated in phantoms, and applied to a human CT colonographic data set. The three algorithms are the cross-sectional area method, the moving spheres method, and the segmental volume method. Each algorithm effectively quantified distention, but accuracy varied between methods. Clinical feasibility was demonstrated. Depending on the desired spatial resolution and accuracy, each algorithm can quantitatively depict colonic diameter in CT colonography.

  2. 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.

  3. 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.

  4. Algorithm development for predicting biodiversity based on phytoplankton absorption

    NASA Astrophysics Data System (ADS)

    Moisan, Tiffany A. H.; Moisan, John R.; Linkswiler, Matthew A.; Steinhardt, Rachel A.

    2013-03-01

    Ocean color remote sensing has provided the scientific community with unprecedented global coverage of chlorophyll a, an indicator of phytoplankton biomass. Together, satellite-derived chlorophyll a and knowledge of Phytoplankton Functional Types (PFTs) will improve our limited understanding of marine ecosystem responses to physiochemical climate drivers involved in carbon cycle dynamics and linkages. Using cruise data from the Gulf of Maine and the Middle Atlantic Bight (N=269 pairs of HPLC and phytoplankton absorption samples), two modeling approaches were utilized to predict phytoplankton absorption and pigments. Algorithm I predicts the chlorophyll-specific absorption coefficient (aph* (m2 mg chl a-1)) using inputs of temperature, light, and chlorophyll a. Modeled r2 values (400-700 nm) ranged from 0.79 to 0.99 when compared to in situ observations with ˜25% lower r2 values in the UV region. Algorithm II-a utilizes matrix inversion analysis to predict a(m-1, 400-700 nm) and r2 values ranged from 0.89 to 0.99. The prediction of phytoplankton pigments with Algorithm II-b produced r2 values that ranged from 0.40 to 0.93. When used in combination, Algorithm I, and Algorithm II-a are able to use satellite products of SST, PAR, and chlorophyll a (Algorithm I) to predict pigment concentrations and ratios to describe the phytoplankton community. The results of this study demonstrate that the spatial variation in modeled pigment ratios differ significantly from the 10-year SeaWiFS average chlorophyll a data set. Contiguous observations of chlorophyll a and phytoplankton biodiversity will elucidate ecosystem responses with unprecedented complexity.

  5. Developing a Learning Algorithm-Generated Empirical Relaxer

    SciTech Connect

    Mitchell, Wayne; Kallman, Josh; Toreja, Allen; Gallagher, Brian; Jiang, Ming; Laney, Dan

    2016-03-30

    One of the main difficulties when running Arbitrary Lagrangian-Eulerian (ALE) simulations is determining how much to relax the mesh during the Eulerian step. This determination is currently made by the user on a simulation-by-simulation basis. We present a Learning Algorithm-Generated Empirical Relaxer (LAGER) which uses a regressive random forest algorithm to automate this decision process. We also demonstrate that LAGER successfully relaxes a variety of test problems, maintains simulation accuracy, and has the potential to significantly decrease both the person-hours and computational hours needed to run a successful ALE simulation.

  6. Evolutionary Processes in the Development of Errors in Subtraction Algorithms

    ERIC Educational Resources Information Center

    Fernandez, Ricardo Lopez; Garcia, Ana B. Sanchez

    2008-01-01

    The study of errors made in subtraction is a research subject approached from different theoretical premises that affect different components of the algorithmic process as triggers of their generation. In the following research an attempt has been made to investigate the typology and nature of errors which occur in subtractions and their evolution…

  7. 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…

  8. The development and evaluation of numerical algorithms for MIMD computers

    NASA Technical Reports Server (NTRS)

    Voigt, Robert G.

    1990-01-01

    Two activities were pursued under this grant. The first was a visitor program to conduct research on numerical algorithms for MIMD computers. The program is summarized in the following attachments. Attachment A - List of Researchers Supported; Attachment B - List of Reports Completed; and Attachment C - Reports. The second activity was a workshop on the Control of fluid Dynamic Systems held on March 28 to 29, 1989. The workshop is summarized in attachments. Attachment D - Workshop Summary; and Attachment E - List of Workshop Participants.

  9. Scientific Knowledge Suppresses but Does Not Supplant Earlier Intuitions

    ERIC Educational Resources Information Center

    Shtulman, Andrew; Valcarcel, Joshua

    2012-01-01

    When students learn scientific theories that conflict with their earlier, naive theories, what happens to the earlier theories? Are they overwritten or merely suppressed? We investigated this question by devising and implementing a novel speeded-reasoning task. Adults with many years of science education verified two types of statements as quickly…

  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. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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…

  16. Collaborative Research Developing, Testing and Validating Brain Alignment Algorithm using Geometric Analysis

    DTIC Science & Technology

    2013-11-13

    This is the final report by the University of Southern California on a AFSOR grant, part of a joint program with Harvard University (PI, Shing-Tung...the algorithm was the task assigned to Harvard University ). Finally, we were to test and validate the algorithm once it had been developed.

  17. Algorithm Development and Application of High Order Numerical Methods for Shocked and Rapid Changing Solutions

    DTIC Science & Technology

    2007-12-06

    problems studied in this project involve numerically solving partial differential equations with either discontinuous or rapidly changing solutions ...REPORT Algorithm Development and Application of High Order Numerical Methods for Shocked and Rapid Changing Solutions 14. ABSTRACT 16. SECURITY...discontinuous Galerkin finite element methods, for solving partial differential equations with discontinuous or rapidly changing solutions . Algorithm

  18. 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.

  19. 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…

  20. 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.

  1. Developing a paradigm of drug innovation: an evaluation algorithm.

    PubMed

    Caprino, Luciano; Russo, Pierluigi

    2006-11-01

    Assessment of drug innovation is a burning issue because it involves so many different perspectives, mainly those of patients, decision- and policy-makers, regulatory authorities and pharmaceutical companies. Moreover, the innovative value of a new medicine is usually an intrinsic property of the compound, but it also depends on the specific context in which the medicine is introduced and the availability of other medicines for treating the same clinical condition. Thus, a model designed to assess drug innovation should be able to capture the intrinsic properties of a compound (which usually emerge during R&D) and/or modification of its innovative value with time. Here we describe the innovation assessment algorithm (IAA), a simulation model for assessing drug innovation. IAA provides a score of drug innovation by assessing information generated during both the pre-marketing and the post-marketing authorization phase.

  2. Development of an algorithm to identify urgent referrals for suspected cancer from the Danish Primary Care Referral Database

    PubMed Central

    Toftegaard, Berit Skjødeberg; Guldbrandt, Louise Mahncke; Flarup, Kaare Rud; Beyer, Hanne; Bro, Flemming; Vedsted, Peter

    2016-01-01

    Background Accurate identification of specific patient populations is a crucial tool in health care. A prerequisite for exploring the actions taken by general practitioners (GPs) on symptoms of cancer is being able to identify patients urgently referred for suspected cancer. Such system is not available in Denmark; however, all referrals are electronically stored. This study aimed to develop and test an algorithm based on referral text to identify urgent cancer referrals from general practice. Methods Two urgently referred reference populations were extracted from a research database and linked with the Primary Care Referral (PCR) database through the unique Danish civil registration number to identify the corresponding electronic referrals. The PCR database included GP referrals directed to private specialists and hospital departments, and these referrals were scrutinized. The most frequently used words were integrated in the first version of the algorithm, which was further refined by an iterative process involving two population samples from the PCR database. The performance was finally evaluated for two other PCR population samples against manual assessment as the gold standard for urgent cancer referral. Results The final algorithm had a sensitivity of 0.939 (95% confidence intervals [CI]: 0.905–0.963) and a specificity of 0.937 (95% CI: 0.925–0.963) compared to the gold standard. The positive and negative predictive values were 69.8% (95% CI: 65.0–74.3) and 99.0% (95% CI: 98.4–99.4), respectively. When applying the algorithm on referrals for a population without earlier cancer diagnoses, the positive predictive value increased to 83.6% (95% CI: 78.7–87.7) and the specificity to 97.3% (95% CI: 96.4–98.0). Conclusion The final algorithm identified 94% of the patients urgently referred for suspected cancer; less than 3% of the patients were incorrectly identified. It is now possible to identify patients urgently referred on cancer suspicion from

  3. 2. VIEW, LOOKING SOUTHEAST, SHOWING PIER OF EARLIER SWING BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW, LOOKING SOUTHEAST, SHOWING PIER OF EARLIER SWING BRIDGE - New York, New Haven & Hartford Railroad, Niantic Bridge, Spanning Niantic River between East Lyme & Waterford, Old Lyme, New London County, CT

  4. Family History of Colon Cancer Calls for Earlier Screening

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_164202.html Family History of Colon Cancer Calls for Earlier Screening ... 2017 (HealthDay News) -- If you've got a family history of colon or rectal cancers, you probably ...

  5. Ice classification algorithm development and verification for the Alaska SAR Facility using aircraft imagery

    NASA Technical Reports Server (NTRS)

    Holt, Benjamin; Kwok, Ronald; Rignot, Eric

    1989-01-01

    The Alaska SAR Facility (ASF) at the University of Alaska, Fairbanks is a NASA program designed to receive, process, and archive SAR data from ERS-1 and to support investigations that will use this regional data. As part of ASF, specialized subsystems and algorithms to produce certain geophysical products from the SAR data are under development. Of particular interest are ice motion, ice classification, and ice concentration. This work focuses on the algorithm under development for ice classification, and the verification of the algorithm using C-band aircraft SAR imagery recently acquired over the Alaskan arctic.

  6. 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.

  7. 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.

  8. Development of a short form and scoring algorithm from the validated actionable bladder symptom screening tool

    PubMed Central

    2013-01-01

    Background The majority of multiple sclerosis (MS) patients develop some form of lower urinary tract dysfunction, usually as a result of neurogenic detrusor overactivity (NDO). Patients identify urinary incontinence as one of the worst aspects of this disease. Despite the high prevalence of NDO, urological evaluation and treatment are significantly under-accessed in this population. The objectives of this study were: 1) to adapt the previously validated Actionable Bladder Symptom Screening Tool (ABSST) to a short form for ease and brevity of application in a clinical setting that is clinically meaningful; and 2) to develop a scoring algorithm that would be interpretable in terms of referring/considering precise diagnosis and treatment. Methods A US-based, non-randomized, multi-center, stand-alone observational study was conducted to assess the psychometric properties of the ABSST among patients who have MS with and without NDO. Mixed psychometric methods (e.g., classical statistics (Psychometric theory (3rd ed.). New York: McGraw-Hill; 1994) and item response methods (Applying the Rasch Model: Fundamental Measurement in the Human Sciences. New Jersey: Lawrence Earlbaum Associates; 2001)) were used to evaluate the predictive and clinical validity of the shortened form. The latter included clinicians flagging clinically meaningful items and associated response options which would indicate the need for further evaluation or treatment. Results A total of 151 patients, all with MS and with and without NDO, were recruited by 28 clinicians in various US geographical locations. Approximately 41% of patients reported a history of or currently having urinary incontinence and/or urinary urgency. The prediction model across the entire range of classification thresholds was evaluated, plotting the true positive identification rate against the false positive rate (1-Specificity) for various cut scores. In this study, the cut-point or total score of greater than or equal to 6 had

  9. Developing a computer algorithm to identify epilepsy cases in managed care organizations.

    PubMed

    Holden, E Wayne; Grossman, Elizabeth; Nguyen, Hoang Thanh; Gunter, Margaret J; Grebosky, Becky; Von Worley, Ann; Nelson, Leila; Robinson, Scott; Thurman, David J

    2005-02-01

    The goal of this study was to develop an algorithm for detecting epilepsy cases in managed care organizations (MCOs). A data set of potential epilepsy cases was constructed from an MCO's administrative data system for all health plan members continuously enrolled in the MCO for at least 1 year within the study period of July 1, 1996 through June 30, 1998. Epilepsy status was determined using medical record review for a sample of 617 cases. The best algorithm for detecting epilepsy cases was developed by examining combinations of diagnosis, diagnostic procedures, and medication use. The best algorithm derived in the exploratory phase was then applied to a new set of data from the same MCO covering the period of July 1, 1998 through June 30, 2000. A stratified sample based on ethnicity and age was drawn from the preliminary algorithm-identified epilepsy cases and non-cases. Medical record review was completed for 644 cases to determine the accuracy of the algorithm. Data from both phases were combined to permit refinement of logistic regression models and to provide more stable estimates of the parameters. The best model used diagnoses and antiepileptic drugs as predictors and had a positive predictive value of 84% (sensitivity 82%, specificity 94%). The best model correctly classified 90% of the cases. A stable algorithm that can be used to identify epilepsy patients within MCOs was developed. Implications for use of the algorithm in other health care settings are discussed.

  10. Generic architecture for real-time multisensor fusion tracking algorithm development and evaluation

    NASA Astrophysics Data System (ADS)

    Queeney, Tom; Woods, Edward

    1994-10-01

    Westinghouse has developed and demonstrated a system for the rapid prototyping of Sensor Fusion Tracking (SFT) algorithms. The system provides an object-oriented envelope with three sets of generic software objects to aid in the development and evaluation of SFT algorithms. The first is a generic tracker model that encapsulates the idea of a tracker being a series of SFT algorithms along with the data manipulated by those algorithms and is capable of simultaneously supporting multiple, independent trackers. The second is a set of flexible, easily extensible sensor and target models which allows many types of sensors and targets to be used. Live, recorded and simulated sensors and combinations thereof can be utilized as sources for the trackers. The sensor models also provide an easily extensible interface to the generic tracker model so that all sensors provide input to the SFT algorithms in the same fashion. The third is a highly versatile display and user interface that allows easy access to many of the performance measures for sensors and trackers for easy evaluation and debugging of the SFT algorithms. The system is an object-oriented design programmed in C++. This system with several of the SFT algorithms developed for it has been used with live sensors as a real-time tracking system. This paper outlines the salient features of the sensor fusion architecture and programming environment.

  11. 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.

  12. Development of a Bayesian recursive algorithm to find free-spaces for an intelligent wheelchair.

    PubMed

    Nguyen, Anh V; Su, Steven; Nguyen, Hung T

    2011-01-01

    This paper introduces a new shared control strategy for an intelligent wheelchair using a Bayesian recursive algorithm. Using the local environment information gathered by a laser range finder sensor and commands acquired through a user interface, a Bayesian recursive algorithm has been developed to find the most appropriate free-space, which corresponds to the highest posterior probability value. Then, an autonomous navigation algorithm will assist to manoeuvre the wheelchair in the chosen free-space. Experiment results demonstrate that the new method provides excellent performance with great flexibility and fast response.

  13. 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.

  14. 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.

  15. 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.

  16. Development of Algorithms for Nonlinear Physics on Type-II Quantum Computers

    DTIC Science & Technology

    2007-07-01

    Jan. 31, 2007 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Quantumn Lattice Algorithms for Nonlinear Physics: Optical Solutions and Bose-Eitistein...macroscopic nonlinear derivatives by local moments. Chapman-Enskog asymptotics will then, on projecting back into physical space, yield these nonlinear ...Entropic Lattice Boltzmaim Model will be being strongly pursued in future proposals. AFOSR FINAL REPORT "DEVELOPMENT OF ALGORITHMS For NONLINEAR

  17. Spectral-Based Volume Sensor Prototype, Post-VS4 Test Series Algorithm Development

    DTIC Science & Technology

    2009-04-30

    Å (NIR), solar - blind UV ( UV ), and 4.3 μm (IR)) and five EVENT algorithms (EVENT, PDSMOKE, FIRE, FIRE_FOV, and WELDING) generating alarm events for... detector are not currently used by any algorithm and, where present, are recorded only for future research and development. The UV units (upper unit...in Figure 2-1) are designed around a standard UV -only OFD (Vibrometer, Inc.). The OmniGuard 860 Optical Flame Detector (Vibrometer, Inc.) used in

  18. 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.

  19. 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).

  20. 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

  1. 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.

  2. Unified framework for development, deployment and robust testing of neuroimaging algorithms.

    PubMed

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

    2011-03-01

    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).

  3. 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.

  4. 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.

  5. Prescription stimulant use is associated with earlier onset of psychosis.

    PubMed

    Moran, Lauren V; Masters, Grace A; Pingali, Samira; Cohen, Bruce M; Liebson, Elizabeth; Rajarethinam, R P; Ongur, Dost

    2015-12-01

    A childhood history of attention deficit hyperactivity disorder (ADHD) is common in psychotic disorders, yet prescription stimulants may interact adversely with the physiology of these disorders. Specifically, exposure to stimulants leads to long-term increases in dopamine release. We therefore hypothesized that individuals with psychotic disorders previously exposed to prescription stimulants will have an earlier onset of psychosis. Age of onset of psychosis (AOP) was compared in individuals with and without prior exposure to prescription stimulants while controlling for potential confounding factors. In a sample of 205 patients recruited from an inpatient psychiatric unit, 40% (n = 82) reported use of stimulants prior to the onset of psychosis. Most participants were prescribed stimulants during childhood or adolescence for a diagnosis of ADHD. AOP was significantly earlier in those exposed to stimulants (20.5 vs. 24.6 years stimulants vs. no stimulants, p < 0.001). After controlling for gender, IQ, educational attainment, lifetime history of a cannabis use disorder or other drugs of abuse, and family history of a first-degree relative with psychosis, the association between stimulant exposure and earlier AOP remained significant. There was a significant gender × stimulant interaction with a greater reduction in AOP for females, whereas the smaller effect of stimulant use on AOP in males did not reach statistical significance. In conclusion, individuals with psychotic disorders exposed to prescription stimulants had an earlier onset of psychosis, and this relationship did not appear to be mediated by IQ or cannabis.

  6. Earlier snowmelt reduces atmospheric carbon uptake in midlatitude subalpine forests

    NASA Astrophysics Data System (ADS)

    Winchell, Taylor S.; Barnard, David M.; Monson, Russell K.; Burns, Sean P.; Molotch, Noah P.

    2016-08-01

    Previous work demonstrates conflicting evidence regarding the influence of snowmelt timing on forest net ecosystem exchange (NEE). Based on 15 years of eddy covariance measurements in Colorado, years with earlier snowmelt exhibited less net carbon uptake during the snow ablation period, which is a period of high potential for productivity. Earlier snowmelt aligned with colder periods of the seasonal air temperature cycle relative to later snowmelt. We found that the colder ablation-period air temperatures during these early snowmelt years lead to reduced rates of daily NEE. Hence, earlier snowmelt associated with climate warming, counterintuitively, leads to colder atmospheric temperatures during the snow ablation period and concomitantly reduced rates of net carbon uptake. Using a multilinear-regression (R2 = 0.79, P < 0.001) relating snow ablation period mean air temperature and peak snow water equivalent (SWE) to ablation-period NEE, we predict that earlier snowmelt and decreased SWE may cause a 45% reduction in midcentury ablation-period net carbon uptake.

  7. Research promises earlier warning for grapevine canker diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When it comes to detecting and treating vineyards for grapevine canker diseases (also called trunk diseases), like Botryosphaeria dieback (Bot canker), Esca, Eutypa dieback and Phomopsis dieback, the earlier the better, says plant pathologist Kendra Baumgartner, with the USDA’s Agricultural Research...

  8. Development of a stereo analysis algorithm for generating topographic maps using interactive techniques of the MPP

    NASA Technical Reports Server (NTRS)

    Strong, James P.

    1987-01-01

    A local area matching algorithm was developed on the Massively Parallel Processor (MPP). It is an iterative technique that first matches coarse or low resolution areas and at each iteration performs matches of higher resolution. Results so far show that when good matches are possible in the two images, the MPP algorithm matches corresponding areas as well as a human observer. To aid in developing this algorithm, a control or shell program was developed for the MPP that allows interactive experimentation with various parameters and procedures to be used in the matching process. (This would not be possible without the high speed of the MPP). With the system, optimal techniques can be developed for different types of matching problems.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  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. 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.

  16. 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.

  17. 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

  18. Developing Fire Detection Algorithms by Geostationary Orbiting Platforms and Machine Learning Techniques

    NASA Astrophysics Data System (ADS)

    Salvador, Pablo; Sanz, Julia; Garcia, Miguel; Casanova, Jose Luis

    2016-08-01

    Fires in general and forest fires specific are a major concern in terms of economical and biological loses. Remote sensing technologies have been focusing on developing several algorithms, adapted to a large kind of sensors, platforms and regions in order to obtain hotspots as faster as possible. The aim of this study is to establish an automatic methodology to develop hotspots detection algorithms with Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensor on board Meteosat Second Generation platform (MSG) based on machine learning techniques that can be exportable to others geostationary platforms and sensors and to any area of the Earth. The sensitivity (SE), specificity (SP) and accuracy (AC) parameters have been analyzed in order to develop the final machine learning algorithm taking into account the preferences and final use of the predicted data.

  19. Innovative testbed for developing and assessing air-to-air noncooperative target identification algorithms

    NASA Astrophysics Data System (ADS)

    Knopow, Jeffrey P.

    1992-07-01

    The development and evaluation of multi-source, multi-spectral, all-aspect airborne target identification algorithms has been proven to be cumbersome as well as disjointed. The algorithm development capability under this testbed concept encompasses model-based reasoning, information fusion, airborne target identification, and target/sensor phenomenology analysis. The evaluation capability assembles multiple sensor and target types coupled with all aspect viewing in an operationally representative air-to-air environment. The importance of developing better techniques for establishing positive target identification for beyond visual ranges has increased in tactical importance, as a result of the Persian Gulf War. In addition to supporting the evaluation of algorithms and associated sensors, this testbed will support on- going R&D in the Air-To-Air Non-Cooperative Target Recognition (NCTR) arena.

  20. Development of algorithms for tsunami detection by High Frequency Radar based on modeling tsunami case studies in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Grilli, S. T.; Guérin, C. A.; Grosdidier, S.

    2014-12-01

    Where coastal tsunami hazard is governed by near-field sources, Submarine Mass Failures (SMFs) or earthquakes, tsunami propagation times may be too small for a detection based on deep or shallow water buoys. To offer sufficient warning time, it has been proposed by others to implement early warning systems relying on High Frequency Radar (HFR) remote sensing, that has a dense spatial coverage far offshore. A new HFR, referred to as STRADIVARIUS, is being deployed by Diginext Inc. (in Fall 2014), to cover the "Golfe du Lion" (GDL) in the Western Mediterranean Sea. This radar uses a proprietary phase coding technology that allows detection up to 300 km, in a bistatic configuration (for which radar and antennas are separated by about 100 km). Although the primary purpose of the radar is vessel detection in relation to homeland security, the 4.5 MHz HFR will provide a strong backscattered signal for ocean surface waves at the so-called Bragg frequency (here, wavelength of 30 m). The current caused by an arriving tsunami will shift the Bragg frequency, by a value proportional to the current magnitude (projected on the local radar ray direction), which can be easily obtained from the Doppler spectrum of the HFR signal. Using state of the art tsunami generation and propagation models, we modeled tsunami case studies in the western Mediterranean basin (both seismic and SMFs) and simulated the HFR backscattered signal that would be detected for the entire GDL and beyond. Based on simulated HFR signal, we developed two types of tsunami detection algorithms: (i) one based on standard Doppler spectra, for which we found that to be detectable within the environmental and background current noises, the Doppler shift requires tsunami currents to be at least 10-15 cm/s, which typically only occurs on the continental shelf in fairly shallow water; (ii) to allow earlier detection, a second algorithm computes correlations of the HFR signals at two distant locations, shifted in time

  1. Development of algorithms for tsunami detection by High Frequency Radar based on modeling tsunami case studies in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Grilli, Stéphan; Guérin, Charles-Antoine; Grosdidier, Samuel

    2015-04-01

    Where coastal tsunami hazard is governed by near-field sources, Submarine Mass Failures (SMFs) or earthquakes, tsunami propagation times may be too small for a detection based on deep or shallow water buoys. To offer sufficient warning time, it has been proposed by others to implement early warning systems relying on High Frequency Surface Wave Radar (HFSWR) remote sensing, that has a dense spatial coverage far offshore. A new HFSWR, referred to as STRADIVARIUS, has been recently deployed by Diginext Inc. to cover the "Golfe du Lion" (GDL) in the Western Mediterranean Sea. This radar, which operates at 4.5 MHz, uses a proprietary phase coding technology that allows detection up to 300 km in a bistatic configuration (with a baseline of about 100 km). Although the primary purpose of the radar is vessel detection in relation to homeland security, it can also be used for ocean current monitoring. The current caused by an arriving tsunami will shift the Bragg frequency by a value proportional to a component of its velocity, which can be easily obtained from the Doppler spectrum of the HFSWR signal. Using state of the art tsunami generation and propagation models, we modeled tsunami case studies in the western Mediterranean basin (both seismic and SMFs) and simulated the HFSWR backscattered signal that would be detected for the entire GDL and beyond. Based on simulated HFSWR signal, we developed two types of tsunami detection algorithms: (i) one based on standard Doppler spectra, for which we found that to be detectable within the environmental and background current noises, the Doppler shift requires tsunami currents to be at least 10-15 cm/s, which typically only occurs on the continental shelf in fairly shallow water; (ii) to allow earlier detection, a second algorithm computes correlations of the HFSWR signals at two distant locations, shifted in time by the tsunami propagation time between these locations (easily computed based on bathymetry). We found that this

  2. Bering Sea shifts toward an earlier spring transition

    NASA Astrophysics Data System (ADS)

    Stabeno, Phyllis J.; Overland, James E.

    Major changes have occurred in the northern high latitudes in the last two decades. These changes range from decreases in marine mammal populations to stratospheric cooling and permafrost warmings. Over Alaska and northwestern Canada, there is an earlier transition from winter to spring. Alaskan natives who live along the coast of the northern Bering Sea have noted warmer spring temperatures, thinner sea ice, and earlier melting of snow and ice. While winters over the northern Bering Sea are cold and dark, the long hours of daylight during spring and summer, coupled with high concentrations of nutrients, make this region among the most productive in the world. Change in timing of the transition between winter and spring is affecting the ecosystem, which in turn will impact the fishermen and natives who use the Bering Sea's living resources.

  3. 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.

  4. Unified development of multiplicative algorithms for linear and quadratic nonnegative matrix factorization.

    PubMed

    Yang, Zhirong; Oja, Erkki

    2011-12-01

    Multiplicative updates have been widely used in approximative nonnegative matrix factorization (NMF) optimization because they are convenient to deploy. Their convergence proof is usually based on the minimization of an auxiliary upper-bounding function, the construction of which however remains specific and only available for limited types of dissimilarity measures. Here we make significant progress in developing convergent multiplicative algorithms for NMF. First, we propose a general approach to derive the auxiliary function for a wide variety of NMF problems, as long as the approximation objective can be expressed as a finite sum of monomials with real exponents. Multiplicative algorithms with theoretical guarantee of monotonically decreasing objective function sequence can thus be obtained. The solutions of NMF based on most commonly used dissimilarity measures such as α- and β-divergence as well as many other more comprehensive divergences can be derived by the new unified principle. Second, our method is extended to a nonseparable case that includes e.g., γ-divergence and Rényi divergence. Third, we develop multiplicative algorithms for NMF using second-order approximative factorizations, in which each factorizing matrix may appear twice. Preliminary numerical experiments demonstrate that the multiplicative algorithms developed using the proposed procedure can achieve satisfactory Karush-Kuhn-Tucker optimality. We also demonstrate NMF problems where algorithms by the conventional method fail to guarantee descent at each iteration but those by our principle are immune to such violation.

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. Development of a multi-objective optimization algorithm using surrogate models for coastal aquifer management

    NASA Astrophysics Data System (ADS)

    Kourakos, George; Mantoglou, Aristotelis

    2013-02-01

    SummaryThe demand for fresh water in coastal areas and islands can be very high due to increased local needs and tourism. A multi-objective optimization methodology is developed, involving minimization of economic and environmental costs while satisfying water demand. The methodology considers desalinization of pumped water and injection of treated water into the aquifer. Variable density aquifer models are computationally intractable when integrated in optimization algorithms. In order to alleviate this problem, a multi-objective optimization algorithm is developed combining surrogate models based on Modular Neural Networks [MOSA(MNNs)]. The surrogate models are trained adaptively during optimization based on a genetic algorithm. In the crossover step, each pair of parents generates a pool of offspring which are evaluated using the fast surrogate model. Then, the most promising offspring are evaluated using the exact numerical model. This procedure eliminates errors in Pareto solution due to imprecise predictions of the surrogate model. The method has important advancements compared to previous methods such as precise evaluation of the Pareto set and alleviation of propagation of errors due to surrogate model approximations. The method is applied to an aquifer in the Greek island of Santorini. The results show that the new MOSA(MNN) algorithm offers significant reduction in computational time compared to previous methods (in the case study it requires only 5% of the time required by other methods). Further, the Pareto solution is better than the solution obtained by alternative algorithms.

  11. Development of administrative data algorithms to identify patients with critical limb ischemia.

    PubMed

    Bekwelem, Wobo; Bengtson, Lindsay G S; Oldenburg, Niki C; Winden, Tamara J; Keo, Hong H; Hirsch, Alan T; Duval, Sue

    2014-12-01

    Administrative data have been used to identify patients with various diseases, yet no prior study has determined the utility of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based codes to identify CLI patients. CLI cases (n=126), adjudicated by a vascular specialist, were carefully defined and enrolled in a hospital registry. Controls were frequency matched to cases on age, sex and admission date in a 2:1 ratio. ICD-9-CM codes for all patients were extracted. Algorithms were developed using frequency distributions of these codes, risk factors and procedures prevalent in CLI. The sensitivity for each algorithm was calculated and applied within the hospital system to identify CLI patients not included in the registry. Sensitivity ranged from 0.29 to 0.92. An algorithm based on diagnosis and procedure codes exhibited the best overall performance (sensitivity of 0.92). Each algorithm had differing CLI identification characteristics based on patient location. Administrative data can be used to identify CLI patients within a health system. The algorithms, developed from these data, can serve as a tool to facilitate clinical care, research, quality improvement, and population surveillance.

  12. 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

  13. Long term analysis of PALS soil moisture campaign measurements for global soil moisture algorithm development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important component of satellite-based soil moisture algorithm development and validation is the comparison of coincident remote sensing and in situ observations that are typically provided by intensive field campaigns. The planned NASA Soil Moisture Active Passive (SMAP) mission has unique requi...

  14. 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.

  15. 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. ...

  16. 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.

  17. Experiences on developing digital down conversion algorithms using Xilinx system generator

    NASA Astrophysics Data System (ADS)

    Xu, Chengfa; Yuan, Yuan; Zhao, Lizhi

    2013-07-01

    The Digital Down Conversion (DDC) algorithm is a classical signal processing method which is widely used in radar and communication systems. In this paper, the DDC function is implemented by Xilinx System Generator tool on FPGA. System Generator is an FPGA design tool provided by Xilinx Inc and MathWorks Inc. It is very convenient for programmers to manipulate the design and debug the function, especially for the complex algorithm. Through the developing process of DDC function based on System Generator, the results show that System Generator is a very fast and efficient tool for FPGA design.

  18. 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.

  19. 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

  20. Development of a doubly weighted Gerchberg-Saxton algorithm for use in multibeam imaging applications.

    PubMed

    Poland, Simon P; Krstajić, Nikola; Knight, Robert D; Henderson, Robert K; Ameer-Beg, Simon M

    2014-04-15

    We report on the development of a doubly weighted Gerchberg-Saxton algorithm (DWGS) to enable generation of uniform beamlet arrays with a spatial light modulator (SLM) for use in multiphoton multifocal imaging applications. The algorithm incorporates the WGS algorithm as well as feedback of fluorescence signals from the sample measured with a single-photon avalanche diode (SPAD) detector array. This technique compensates for issues associated with nonuniform illumination onto the SLM, the effects due to aberrations and the variability in gain between detectors within the SPAD array to generate a uniformly illuminated multiphoton fluorescence image. We demonstrate the use of the DWGS with a number of beamlet array patterns to image muscle fibers of a 5-day-old fixed zebrafish larvae.

  1. 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.

  2. Development of a MELCOR self-initialization algorithm for boiling water reactors

    SciTech Connect

    Chien, C.S.; Wang, S.J.; Cheng, S.K.

    1996-01-01

    The MELCOR code, developed by Sandia National Laboratories, is suitable for calculating source terms and simulating severe accident phenomena of nuclear power plants. Prior to simulating a severe accident transient with MELCOR, the initial steady-state conditions must be generated in advance. The current MELCOR users` manuals do not provide a self-initialization procedure; this is the reason users have to adjust the initial conditions by themselves through a trial-and-error approach. A MELCOR self-initialization algorithm for boiling water reactor plants has been developed, which eliminates the tedious trial-and-error procedures and improves the simulation accuracy. This algorithm adjusts the important plant variable such as the dome pressure, downcomer level, and core flow rate to the desired conditions automatically. It is implemented through input with control functions provided in MELCOR. The reactor power and feedwater temperature are fed as input data. The initialization work of full-power conditions of the Kuosheng nuclear power station is cited as an example. These initial conditions are generated successfully with the developed algorithm. The generated initial conditions can be stored in a restart file and used for transient analysis. The methodology in this study improves the accuracy and consistency of transient calculations. Meanwhile, the algorithm provides all MELCOR users an easy and correct method for establishing the initial conditions.

  3. 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.

  4. 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

    1995-01-01

    During the second phase project year we have made progress in the development and refinement of surface temperature retrieval algorithms and in product generation. More specifically, we have accomplished the following: (1) acquired a new advanced very high resolution radiometer (AVHRR) data set for the Beaufort Sea area spanning an entire year; (2) acquired additional along-track scanning radiometer(ATSR) data for the Arctic and Antarctic now totalling over eight months; (3) refined our AVHRR Arctic and Antarctic ice surface temperature (IST) retrieval algorithm, including work specific to Greenland; (4) developed ATSR retrieval algorithms for the Arctic and Antarctic, including work specific to Greenland; (5) developed cloud masking procedures for both AVHRR and ATSR; (6) generated a two-week bi-polar global area coverage (GAC) set of composite images from which IST is being estimated; (7) investigated the effects of clouds and the atmosphere on passive microwave 'surface' temperature retrieval algorithms; and (8) generated surface temperatures for the Beaufort Sea data set, both from AVHRR and special sensor microwave imager (SSM/I).

  5. 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.

  6. Earlier vegetation green-up has reduced spring dust storms.

    PubMed

    Fan, Bihang; Guo, Li; Li, Ning; Chen, Jin; Lin, Henry; Zhang, Xiaoyang; Shen, Miaogen; Rao, Yuhan; Wang, Cong; Ma, Lei

    2014-10-24

    The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = -0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world.

  7. Earlier vegetation green-up has reduced spring dust storms

    PubMed Central

    Fan, Bihang; Guo, Li; Li, Ning; Chen, Jin; Lin, Henry; Zhang, Xiaoyang; Shen, Miaogen; Rao, Yuhan; Wang, Cong; Ma, Lei

    2014-01-01

    The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = −0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world. PMID:25343265

  8. Scientific knowledge suppresses but does not supplant earlier intuitions.

    PubMed

    Shtulman, Andrew; Valcarcel, Joshua

    2012-08-01

    When students learn scientific theories that conflict with their earlier, naïve theories, what happens to the earlier theories? Are they overwritten or merely suppressed? We investigated this question by devising and implementing a novel speeded-reasoning task. Adults with many years of science education verified two types of statements as quickly as possible: statements whose truth value was the same across both naïve and scientific theories of a particular phenomenon (e.g., "The moon revolves around the Earth") and statements involving the same conceptual relations but whose truth value differed across those theories (e.g., "The Earth revolves around the sun"). Participants verified the latter significantly more slowly and less accurately than the former across 10 domains of knowledge (astronomy, evolution, fractions, genetics, germs, matter, mechanics, physiology, thermodynamics, and waves), suggesting that naïve theories survive the acquisition of a mutually incompatible scientific theory, coexisting with that theory for many years to follow.

  9. Changes toward earlier streamflow timing across western North America

    USGS Publications Warehouse

    Stewart, I.T.; Cayan, D.R.; Dettinger, M.D.

    2005-01-01

    The highly variable timing of streamflow in snowmelt-dominated basins across western North America is an important consequence, and indicator, of climate fluctuations. Changes in the timing of snowmelt-derived streamflow from 1948 to 2002 were investigated in a network of 302 western North America gauges by examining the center of mass for flow, spring pulse onset dates, and seasonal fractional flows through trend and principal component analyses. Statistical analysis of the streamflow timing measures with Pacific climate indicators identified local and key large-scale processes that govern the regionally coherent parts of the changes and their relative importance. Widespread and regionally coherent trends toward earlier onsets of springtime snowmelt and streamflow have taken place across most of western North America, affecting an area that is much larger than previously recognized. These timing changes have resulted in increasing fractions of annual flow occurring earlier in the water year by 1-4 weeks. The immediate (or proximal) forcings for the spatially coherent parts of the year-to-year fluctuations and longer-term trends of streamflow timing have been higher winter and spring temperatures. Although these temperature changes are partly controlled by the decadal-scale Pacific climate mode [Pacific decadal oscillation (PDO)], a separate and significant part of the variance is associated with a springtime warming trend that spans the PDO phases. ?? 2005 American Meteorological Society.

  10. Glycemic management in ESRD and earlier stages of CKD.

    PubMed

    Williams, Mark E; Garg, Rajesh

    2014-02-01

    The management of hyperglycemia in patients with kidney failure is complex, and the goals and methods regarding glycemic control in chronic kidney disease (CKD) are not clearly defined. Although aggressive glycemic control seems to be advantageous in early diabetic nephropathy, outcome data supporting tight glycemic control in patients with advanced CKD (including end-stage renal disease [ESRD]) are lacking. Challenges in the management of such patients include therapeutic inertia, monitoring difficulties, and the complexity of available treatments. In this article, we review the alterations in glucose homeostasis that occur in kidney failure, current views on the value of glycemic control and issues with its determination, and more recent approaches to monitor or measure glycemic control. Hypoglycemia and treatment options for patients with diabetes and ESRD or earlier stages of CKD also are addressed, discussing the insulin and noninsulin agents that currently are available, along with their indications and contraindications. The article provides information to help clinicians in decision making in order to provide individualized glycemic goals and appropriate therapy for patients with ESRD or earlier stages of CKD.

  11. 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.

  12. Development of potential methods for testing congestion control algorithm implemented in vehicle to vehicle communications.

    PubMed

    Hsu, Chung-Jen; Fikentscher, Joshua; Kreeb, Robert

    2017-03-21

    Objective A channel congestion problem might occur when the traffic density increases since the number of basic safety messages carried on the communication channel also increases in vehicle-to-vehicle communications. A remedy algorithm proposed in SAE J2945/1 is designed to address the channel congestion issue by decreasing transmission frequency and radiated power. This study is to develop potential test procedures for evaluating or validating the congestion control algorithm. Methods Simulations of a reference unit transmitting at a higher frequency are implemented to emulate a number of Onboard Equipment (OBE) transmitting at the normal interval of 100 milliseconds (10 Hz). When the transmitting interval is reduced to 1.25 milliseconds (800 Hz), the reference unit emulates 80 vehicles transmitting at 10 Hz. By increasing the number of reference units transmitting at 800 Hz in the simulations, the corresponding channel busy percentages are obtained. An algorithm for GPS data generation of virtual vehicles is developed for facilitating the validation of transmission intervals in the congestion control algorithm. Results Channel busy percentage is the channel busy time over a specified period of time. Three or four reference units are needed to generate channel busy percentages between 50% and 80%, and five reference units can generate channel busy percentages above 80%. The proposed test procedures can verify the operation of congestion control algorithm when channel busy percentages are between 50% and 80%, and above 80%. By using GPS data generation algorithm, the test procedures can also verify the transmission intervals when traffic densities are 80 and 200 vehicles in the radius of 100 m. A suite of test tools with functional requirements is also proposed for facilitating the implementation of test procedures. Conclusions The potential test procedures for congestion control algorithm are developed based on the simulation results of channel busy

  13. Developing a synergy algorithm for land surface temperature: the SEN4LST project

    NASA Astrophysics Data System (ADS)

    Sobrino, Jose A.; Jimenez, Juan C.; Ghent, Darren J.

    2013-04-01

    Land surface Temperature (LST) is one of the key parameters in the physics of land-surface processes on regional and global scales, combining the results of all surface-atmosphere interactions and energy fluxes between the surface and the atmosphere. An adequate characterization of LST distribution and its temporal evolution requires measurements with detailed spatial and temporal frequencies. With the advent of the Sentinel 2 (S2) and 3 (S3) series of satellites a unique opportunity exists to go beyond the current state of the art of single instrument algorithms. The Synergistic Use of The Sentinel Missions For Estimating And Monitoring Land Surface Temperature (SEN4LST) project aims at developing techniques to fully utilize synergy between S2 and S3 instruments in order to improve LST retrievals. In the framework of the SEN4LST project, three LST retrieval algorithms were proposed using the thermal infrared bands of the Sea and Land Surface Temperature Retrieval (SLSTR) instrument on board the S3 platform: split-window (SW), dual-angle (DA) and a combined algorithm using both split-window and dual-angle techniques (SW-DA). One of the objectives of the project is to select the best algorithm to generate LST products from the synergy between S2/S3 instruments. In this sense, validation is a critical step in the selection process for the best performing candidate algorithm. A unique match-up database constructed at University of Leicester (UoL) of in situ observations from over twenty ground stations and corresponding brightness temperature (BT) and LST match-ups from multi-sensor overpasses is utilised for validating the candidate algorithms. Furthermore, their performance is also evaluated against the standard ESA LST product and the enhanced offline UoL LST product. In addition, a simulation dataset is constructed using 17 synthetic images of LST and the radiative transfer model MODTRAN carried under 66 different atmospheric conditions. Each candidate LST

  14. Reconstruction of an object from its Fourier modulus: development of the combination algorithm composed of the hybrid input-output algorithm and its converging part

    NASA Astrophysics Data System (ADS)

    Takajo, Hiroaki; Takahashi, Tohru; Itoh, Katsuhiko; Fujisaki, Toshiro

    2002-10-01

    The hybrid input-output algorithm (HIO) used for phase retrieval is in many cases combined with the error-reduction algorithm (ER) to attempt to stabilize the HIO. However, in our previous paper [J. Opt. Soc. Am. A 16, 2163 (1999)], it was demonstrated that this combination makes it more likely that the resultant algorithm will fall into a periodic state before reaching a solution because the values of the input object outside the support, which is imposed as the object-domain constraint, are set to be zero in the intervals in which the ER is implemented. This paper deals with this problem inherent in the combination algorithm. The converging part of the HIO (CPHIO), which is an algorithm we previously developed [J. Opt. Soc. Am. A 15, 2849 (1998)], can be thought of as an extension of the ER for the case in which the input object can have nonzero values outside the support. Keeping this in mind, the algorithm is then constructed by combining the HIO with the CPHIO instead of with the ER. The computer simulation results that demonstrate the effectiveness of the proposed algorithm are given.

  15. Reconstruction of an object from its Fourier modulus: development of the combination algorithm composed of the hybrid input-output algorithm and its converging part.

    PubMed

    Takajo, Hiroaki; Takahashi, Tohru; Itoh, Katsuhiko; Fujisaki, Toshiro

    2002-10-10

    The hybrid input-output algorithm (HIO) used for phase retrieval is in many cases combined with the error-reduction algorithm (ER) to attempt to stabilize the HIO. However, in our previous paper [J. Opt. Soc. Am. A 16, 2163 (1999)], it was demonstrated that this combination makes it more likely that the resultant algorithm will fall into a periodic state before reaching a solution because the values of the input object outside the support, which is imposed as the object-domain constraint, are set to be zero in the intervals in which the ER is implemented. This paper deals with this problem inherent in the combination algorithm. The converging part of the HIO (CPHIO), which is an algorithm we previously developed [J. Opt. Soc. Am. A 15, 2849 (1998)], can be thought of as an extension of the ER for the case in which the input object can have nonzero values outside the support. Keeping this in mind, the algorithm is then constructed by combining the HIO with the CPHIO instead of with the ER. The computer simulation results that demonstrate the effectiveness of the proposed algorithm are given.

  16. Trend of earlier spring in central Europe continued

    NASA Astrophysics Data System (ADS)

    Ungersböck, Markus; Jurkovic, Anita; Koch, Elisabeth; Lipa, Wolfgang; Scheifinger, Helfried; Zach-Hermann, Susanne

    2013-04-01

    Modern phenology is the study of the timing of recurring biological events in the animal and plant world, the causes of their timing with regard to biotic and abiotic forces, and the interrelation among phases of the same or different species. The relationship between phenology and climate explains the importance of plant phenology for Climate Change studies. Plants require light, water, oxygen mineral nutrients and suitable temperature to grow. In temperate zones the seasonal life cycle of plants is primarily controlled by temperature and day length. Higher spring air temperatures are resulting in an earlier onset of the phenological spring in temperate and cool climate. On the other hand changes in phenology due to climate change do have impact on the climate system itself. Vegetation is a dynamic factor in the earth - climate system and has positive and negative feedback mechanisms to the biogeochemical and biogeophysical fluxes to the atmosphere Since the mid of the 1980s spring springs earlier in Europe and autumn is shifting back to the end of the year resulting in a longer vegetation period. The advancement of spring can be clearly attributed to temperature increase in the months prior to leaf unfolding and flowering, the timing of autumn is more complex and cannot easily be attributed to one or some few parameters. To demonstrate that the observed advancement of spring since the mid of 1980s is pro-longed in 2001 to 2010 and the delay of fall and the lengthening of the growing season is confirmed in the last decade we picked out several indicator plants from the PEP725 database www.pep725.eu. The PEP725 database collects data from different European network operators and thus offers a unique compilation of phenological observations; the database is regularly updated. The data follow the same classification scheme, the so called BBCH coding system so they can be compared. Lilac Syringa vulgaris, birch Betula pendula, beech Fagus and horse chestnut Aesculus

  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. Development of an IMU-based foot-ground contact detection (FGCD) algorithm.

    PubMed

    Kim, Myeongkyu; Lee, Donghun

    2017-03-01

    It is well known that, to locate humans in GPS-denied environments, a lower limb kinematic solution based on Inertial Measurement Unit (IMU), force plate, and pressure insoles is essential. The force plate and pressure insole are used to detect foot-ground contacts. However, the use of multiple sensors is not desirable in most cases. This paper documents the development of an IMU-based FGCD (foot-ground contact detection) algorithm considering the variations of both walking terrain and speed. All IMU outputs showing significant changes on the moments of foot-ground contact phases are fully identified through experiments in five walking terrains. For the experiment on each walking terrain, variations of walking speeds are also examined to confirm the correlations between walking speed and the main parameters in the FGCD algorithm. As experimental results, FGCD algorithm successfully detecting four contact phases is developed, and validation of performance of the FGCD algorithm is also implemented. Practitioner Summary: In this research, it was demonstrated that the four contact phases of Heel strike (or Toe strike), Full contact, Heel off and Toe off can be independently detected regardless of the walking speed and walking terrain based on the detection criteria composed of the ranges and the rates of change of the main parameters measured from the Inertial Measurement Unit sensors.

  19. 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

  20. jClustering, an open framework for the development of 4D clustering algorithms.

    PubMed

    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.

  1. 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.

  2. 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.

  3. 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.

  4. Application of custom tools and algorithms to the development of terrain and target models

    NASA Astrophysics Data System (ADS)

    Wilkosz, Aaron; Williams, Bryan L.; Motz, Steve

    2003-09-01

    In this paper we give a high level discussion outlining methodologies and techniques employed in generating high fidelity terrain and target models. We present the current state of our IR signature development efforts, cover custom tools and algorithms, and discuss future plans. We outline the steps required to derive an IR terrain and target signature models, and provide some details about algorithms developed to classify aerial imagery. In addition, we discuss our tool used to apply IR signature data to tactical vehicle models. We discuss how we process the empirical IR data of target vehicles, apply it to target models, and generate target signature models that correlate with the measured calibrated IR data. The developed characterization databases and target models are used in digital simulations by various customers within the US Army Aviation and Missile Command (AMCOM).

  5. 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.

  6. Development of a novel algorithm to determine adherence to chronic pain treatment guidelines using administrative claims

    PubMed Central

    Margolis, Jay M; Princic, Nicole; Smith, David M; Abraham, Lucy; Cappelleri, Joseph C; Shah, Sonali N; Park, Peter W

    2017-01-01

    Objective To develop a claims-based algorithm for identifying patients who are adherent versus nonadherent to published guidelines for chronic pain management. Methods Using medical and pharmacy health care claims from the MarketScan® Commercial and Medicare Supplemental Databases, patients were selected during July 1, 2010, to June 30, 2012, with the following chronic pain conditions: osteoarthritis (OA), gout (GT), painful diabetic peripheral neuropathy (pDPN), post-herpetic neuralgia (PHN), and fibromyalgia (FM). Patients newly diagnosed with 12 months of continuous medical and pharmacy benefits both before and after initial diagnosis (index date) were categorized as adherent, nonadherent, or unsure according to the guidelines-based algorithm using disease-specific pain medication classes grouped as first-line, later-line, or not recommended. Descriptive and multivariate analyses compared patient outcomes with algorithm-derived categorization endpoints. Results A total of 441,465 OA patients, 76,361 GT patients, 10,645 pDPN, 4,010 PHN patients, and 150,321 FM patients were included in the development of the algorithm. Patients found adherent to guidelines included 51.1% for OA, 25% for GT, 59.5% for pDPN, 54.9% for PHN, and 33.5% for FM. The majority (~90%) of patients adherent to the guidelines initiated therapy with prescriptions for first-line pain medications written for a minimum of 30 days. Patients found nonadherent to guidelines included 30.7% for OA, 6.8% for GT, 34.9% for pDPN, 23.1% for PHN, and 34.7% for FM. Conclusion This novel algorithm used real-world pharmacotherapy treatment patterns to evaluate adherence to pain management guidelines in five chronic pain conditions. Findings suggest that one-third to one-half of patients are managed according to guidelines. This method may have valuable applications for health care payers and providers analyzing treatment guideline adherence. PMID:28223842

  7. 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.

  8. Developments of a force image algorithm for micromachined optical bend loss sensor

    NASA Astrophysics Data System (ADS)

    Huang, Chu-Yu; Liu, Chao-Shih; Panergo, Reynold; Huang, Cheng-Sheng; Wang, Wei-Chih

    2005-05-01

    A flexible high-resolution sensor capable of measuring the distribution of both shear and pressure at the plantar interface are needed to study the actual distribution of this force during daily activities, and the role that shear plays in causing plantar ulceration. We have previously developed a novel means of transducing plantar shear and pressure stress via a new microfabricated optical system. However, a force image algorithm is needed to handle the complexity of construction of two-dimensional planar pressure and shear images. Here we have developed a force image algorithm for a micromachined optical bend loss sensor. A neural network is introduced to help identify different load shapes. According to the experimental result, we can conclude that once the neural network has been well trained, it can correctly identify the loading shape. With the neural network, our micromachined optical bend loss Sensor is able to construction the two-dimensional planar force images.

  9. Development of Cloud and Precipitation Property Retrieval Algorithms and Measurement Simulators from ASR Data

    SciTech Connect

    Mace, Gerald G.

    2016-02-10

    What has made the ASR program unique is the amount of information that is available. The suite of recently deployed instruments significantly expands the scope of the program (Mather and Voyles, 2013). The breadth of this information allows us to pose sophisticated process-level questions. Our ASR project, now entering its third year, has been about developing algorithms that use this information in ways that fully exploit the new capacity of the ARM data streams. Using optimal estimation (OE) and Markov Chain Monte Carlo (MCMC) inversion techniques, we have developed methodologies that allow us to use multiple radar frequency Doppler spectra along with lidar and passive constraints where data streams can be added or subtracted efficiently and algorithms can be reformulated for various combinations of hydrometeors by exchanging sets of empirical coefficients. These methodologies have been applied to boundary layer clouds, mixed phase snow cloud systems, and cirrus.

  10. 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.

  11. Development and Evaluation of Single-Microphone Noise Reduction Algorithms for Digital Hearing Aids

    NASA Astrophysics Data System (ADS)

    Marzinzik, Mark; Kollmeier, Birger

    In this study single-microphone noise reduction procedures were investigated for use in digital hearing aids. One widely reported artifact of most noise suppression systems, the musical noise phenomenon, can partly be overcome by the Ephraim-Malah noise suppression algorithms [1,2]. Based on these algorithms, three different versions have been implemented together with a procedure for automatically updating the noise-spectrum estimate. To evaluate the algorithms, different tests have been performed with six normal-hearing and six hearing-impaired subjects. With `standard' measurement methods no increase in speech intelligibility was found compared to the unprocessed signal. However, benefits with respect to reductions in listener fatigue and in the mental effort needed to listen to speech in noise over longer periods of time were found in this study by use of a newly developed ease-of-listening test. Subsequent paired comparison tests also revealed a clear preference of the hearing-impaired subjects for the noise-reduced signals in situations with rather stationary noise. In the case of strongly fluctuating noise at low SNR, however, the subjects preferred the unprocessed signal due to speech distortions caused by the noise reduction algorithms.

  12. Development and application of efficient pathway enumeration algorithms for metabolic engineering applications.

    PubMed

    Liu, F; Vilaça, P; Rocha, I; Rocha, M

    2015-02-01

    Metabolic Engineering (ME) aims to design microbial cell factories towards the production of valuable compounds. In this endeavor, one important task relates to the search for the most suitable heterologous pathway(s) to add to the selected host. Different algorithms have been developed in the past towards this goal, following distinct approaches spanning constraint-based modeling, graph-based methods and knowledge-based systems based on chemical rules. While some of these methods search for pathways optimizing specific objective functions, here the focus will be on methods that address the enumeration of pathways that are able to convert a set of source compounds into desired targets and their posterior evaluation according to different criteria. Two pathway enumeration algorithms based on (hyper)graph-based representations are selected as the most promising ones and are analyzed in more detail: the Solution Structure Generation and the Find Path algorithms. Their capabilities and limitations are evaluated when designing novel heterologous pathways, by applying these methods on three case studies of synthetic ME related to the production of non-native compounds in E. coli and S. cerevisiae: 1-butanol, curcumin and vanillin. Some targeted improvements are implemented, extending both methods to address limitations identified that impair their scalability, improving their ability to extract potential pathways over large-scale databases. In all case-studies, the algorithms were able to find already described pathways for the production of the target compounds, but also alternative pathways that can represent novel ME solutions after further evaluation.

  13. 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.

  14. 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.

  15. 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.

  16. Development of a validated algorithm for the diagnosis of paediatric asthma in electronic medical records

    PubMed Central

    Cave, Andrew J; Davey, Christina; Ahmadi, Elaheh; Drummond, Neil; Fuentes, Sonia; Kazemi-Bajestani, Seyyed Mohammad Reza; Sharpe, Heather; Taylor, Matt

    2016-01-01

    An accurate estimation of the prevalence of paediatric asthma in Alberta and elsewhere is hampered by uncertainty regarding disease definition and diagnosis. Electronic medical records (EMRs) provide a rich source of clinical data from primary-care practices that can be used in better understanding the occurrence of the disease. The Canadian Primary Care Sentinel Surveillance Network (CPCSSN) database includes cleaned data extracted from the EMRs of primary-care practitioners. The purpose of the study was to develop and validate a case definition of asthma in children 1–17 who consult family physicians, in order to provide primary-care estimates of childhood asthma in Alberta as accurately as possible. The validation involved the comparison of the application of a theoretical algorithm (to identify patients with asthma) to a physician review of records included in the CPCSSN database (to confirm an accurate diagnosis). The comparison yielded 87.4% sensitivity, 98.6% specificity and a positive and negative predictive value of 91.2% and 97.9%, respectively, in the age group 1–17 years. The algorithm was also run for ages 3–17 and 6–17 years, and was found to have comparable statistical values. Overall, the case definition and algorithm yielded strong sensitivity and specificity metrics and was found valid for use in research in CPCSSN primary-care practices. The use of the validated asthma algorithm may improve insight into the prevalence, diagnosis, and management of paediatric asthma in Alberta and Canada. PMID:27882997

  17. 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

  18. Progress on the development of automated data analysis algorithms and software for ultrasonic inspection of composites

    NASA Astrophysics Data System (ADS)

    Aldrin, John C.; Coughlin, Chris; Forsyth, David S.; Welter, John T.

    2014-02-01

    Progress is presented on the development and implementation of automated data analysis (ADA) software to address the burden in interpreting ultrasonic inspection data for large composite structures. The automated data analysis algorithm is presented in detail, which follows standard procedures for analyzing signals for time-of-flight indications and backwall amplitude dropout. ADA processing results are presented for test specimens that include inserted materials and discontinuities produced under poor manufacturing conditions.

  19. 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.

  20. Poorest countries experience earlier anthropogenic emergence of daily temperature extremes

    NASA Astrophysics Data System (ADS)

    Harrington, Luke J.; Frame, David J.; Fischer, Erich M.; Hawkins, Ed; Joshi, Manoj; Jones, Chris D.

    2016-05-01

    Understanding how the emergence of the anthropogenic warming signal from the noise of internal variability translates to changes in extreme event occurrence is of crucial societal importance. By utilising simulations of cumulative carbon dioxide (CO2) emissions and temperature changes from eleven earth system models, we demonstrate that the inherently lower internal variability found at tropical latitudes results in large increases in the frequency of extreme daily temperatures (exceedances of the 99.9th percentile derived from pre-industrial climate simulations) occurring much earlier than for mid-to-high latitude regions. Most of the world’s poorest people live at low latitudes, when considering 2010 GDP-PPP per capita; conversely the wealthiest population quintile disproportionately inhabit more variable mid-latitude climates. Consequently, the fraction of the global population in the lowest socio-economic quintile is exposed to substantially more frequent daily temperature extremes after much lower increases in both mean global warming and cumulative CO2 emissions.

  1. Earlier North American Monsoon Onset in a Warmer World?

    NASA Astrophysics Data System (ADS)

    Rauscher, S. A.; Seth, A.; Ringler, T.; Rojas, M.; Liebmann, B.

    2009-12-01

    Analysis of twenty-first century projections indicate substantial drying over the American Southwest and the potential for “Dust Bowl” conditions to be the norm by the middle of century. Closer examination of monthly precipitation data from the CMIP3 models indicates that the annual cycle is actually amplified over the North American Monsoon (NAMS) region, with drier conditions during the winter and an increase in monsoon rains during the later part of the rainy season. Importantly, the projected decrease in winter precipitation extends into the spring season, suggesting a delayed onset of the NAMS. Consistent thermodynamic changes, including a decrease in low-level relative humidity and an increase in the vertical gradient of moist static energy, accompany this spring precipitation decrease. Here we examine daily precipitation data from the CMIP3 archive to determine if this reduced spring precipitation represents a true delay in the NAMS onset. We further analyze the hydrological cycle over the NAMS region in several of the CMIP3 models, focusing on changes in net moisture divergence, surface evaporation, and soil moisture in order to fully understand how the hydrological cycle will change in the future based on the CMIP3 simulations, and how these changes may be translated into the timing and intensity of the NAMS. The combination of a delayed NAMS onset and earlier and reduced snowmelt runoff in the western US could substantially change the availability of water resources over the NAMS region.

  2. Earlier speech exposure does not accelerate speech acquisition.

    PubMed

    Peña, Marcela; Werker, Janet F; Dehaene-Lambertz, Ghislaine

    2012-08-15

    Critical periods in language acquisition have been discussed primarily with reference to studies of people who are deaf or bilingual. Here, we provide evidence on the opening of sensitivity to the linguistic environment by studying the response to a change of phoneme at a native and nonnative phonetic boundary in full-term and preterm human infants using event-related potentials. Full-term infants show a decline in their discrimination of nonnative phonetic contrasts between 9 and 12 months of age. Because the womb is a high-frequency filter, many phonemes are strongly degraded in utero. Preterm infants thus benefit from earlier and richer exposure to broadcast speech. We find that preterms do not take advantage of this enriched linguistic environment: the decrease in amplitude of the mismatch response to a nonnative change of phoneme at the end of the first year of life was dependent on maturational age and not on the duration of exposure to broadcast speech. The shaping of phonological representations by the environment is thus strongly constrained by brain maturation factors.

  3. Development of an algorithm for identifying rheumatoid arthritis in the Korean National Health Insurance claims database.

    PubMed

    Cho, Soo-Kyung; Sung, Yoon-Kyoung; Choi, Chan-Bum; Kwon, Jeong-Mi; Lee, Eui-Kyung; Bae, Sang-Cheol

    2013-12-01

    This study aimed to develop an identification algorithm for validating the International Classification of Diseases-Tenth diagnostic codes for rheumatoid arthritis (RA) in the Korean National Health Insurance (NHI) claims database. An individual copayment beneficiaries program for rare and intractable diseases, including seropositive RA (M05), began in South Korea in July 2009. Patients registered in this system pay only 10 % of their total medical costs, but registration requires an official report from a doctor documenting that the patient fulfills the 1987 ACR criteria. We regarded patients registered in this system as gold standard RA and examined the validity of several algorithms to define RA diagnosis using diagnostic codes and prescription data. We constructed nine algorithms using two highly specific prescriptions (positive predictive value >90 % and specificity >90 %) and one prescription with high sensitivity (>80 %) and accuracy (>75 %). A total of 59,823 RA patients were included in this validation study. Among them, 50,082 (83.7 %) were registered in the individual copayment beneficiaries program and considered true RA. We tested nine algorithms that incorporated two specific regimens [biologics and leflunomide alone, methotrexate plus leflunomide, or more than 3 disease-modifying anti-rheumatic drugs (DMARDs)] and one sensitive drug (any non-steroidal anti-inflammatory drug (NSAID), any DMARD, or any NSAID plus any DMARD). The algorithm that included biologics, more than 3 DMARDs, and any DMARD yielded the highest accuracy (91.4 %). Patients with RA diagnostic codes with prescription of biologics or any DMARD can be considered as accurate cases of RA in Korean NHI claims database.

  4. 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

  5. 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

  6. Development of algorithms for building inventory compilation through remote sensing and statistical inferencing

    NASA Astrophysics Data System (ADS)

    Sarabandi, Pooya

    Building inventories are one of the core components of disaster vulnerability and loss estimations models, and as such, play a key role in providing decision support for risk assessment, disaster management and emergency response efforts. In may parts of the world inclusive building inventories, suitable for the use in catastrophe models cannot be found. Furthermore, there are serious shortcomings in the existing building inventories that include incomplete or out-dated information on critical attributes as well as missing or erroneous values for attributes. In this dissertation a set of methodologies for updating spatial and geometric information of buildings from single and multiple high-resolution optical satellite images are presented. Basic concepts, terminologies and fundamentals of 3-D terrain modeling from satellite images are first introduced. Different sensor projection models are then presented and sources of optical noise such as lens distortions are discussed. An algorithm for extracting height and creating 3-D building models from a single high-resolution satellite image is formulated. The proposed algorithm is a semi-automated supervised method capable of extracting attributes such as longitude, latitude, height, square footage, perimeter, irregularity index and etc. The associated errors due to the interactive nature of the algorithm are quantified and solutions for minimizing the human-induced errors are proposed. The height extraction algorithm is validated against independent survey data and results are presented. The validation results show that an average height modeling accuracy of 1.5% can be achieved using this algorithm. Furthermore, concept of cross-sensor data fusion for the purpose of 3-D scene reconstruction using quasi-stereo images is developed in this dissertation. The developed algorithm utilizes two or more single satellite images acquired from different sensors and provides the means to construct 3-D building models in a more

  7. 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.

  8. 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

  9. Chronic wrist pain: diagnosis and management. Development and use of a new algorithm

    PubMed Central

    van Vugt, R. M; Bijlsma, J.; van Vugt, A. C

    1999-01-01

    OBJECTIVE—Chronic wrist pain can be difficult to manage and the differential diagnosis is extensive. To provide guidelines for assessment of the painful wrist an algorithm was developed to encourage a structured approach to the diagnosis and management of these patients.
METHODS—A review of the literature on causes of chronic wrist pain was undertaken; history taking, physical examination and imaging studies were evaluated systematically to determine which of the many potential conditions was the cause of the wrist pain. Chronic wrist pain was subdivided into pain of probable intra-articular or extra-articular origin. By means of this classification a clinical algorithm was developed to establish a diagnosis and its clinical usefulness was tested in a prospective study of 84 patients presenting to our outpatient clinic.
RESULTS—A definite diagnosis could be established in 59% (49 of 84) of the cases by careful history taking, extensive physical examination, plain radiographs, ultrasound examination and bone scintigraphy. In 19% of the cases (16 of 84) a probable diagnosis was made resulting in a total figure 78% (65 of 84). Additional imaging studies (arthrography, magnetic resonance imaging and computed tomography) increased the definite diagnoses to 70% (59 of 84).
CONCLUSION—The algorithm proved easy to use and by the use of careful history taking, thorough physical examination and simple imaging techniques (ultrasonography and scintigraphy) a diagnosis was made in 78% of cases.

 PMID:10531069

  10. 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.

  11. 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.

  12. 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.

  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. Development of Serum Marker Models to Increase Diagnostic Accuracy of Advanced Fibrosis in Nonalcoholic Fatty Liver Disease: The New LINKI Algorithm Compared with Established Algorithms

    PubMed Central

    Lykiardopoulos, Byron; Hagström, Hannes; Fredrikson, Mats; Ignatova, Simone; Stål, Per; Hultcrantz, Rolf; Ekstedt, Mattias

    2016-01-01

    Background and Aim Detection of advanced fibrosis (F3-F4) in nonalcoholic fatty liver disease (NAFLD) is important for ascertaining prognosis. Serum markers have been proposed as alternatives to biopsy. We attempted to develop a novel algorithm for detection of advanced fibrosis based on a more efficient combination of serological markers and to compare this with established algorithms. Methods We included 158 patients with biopsy-proven NAFLD. Of these, 38 had advanced fibrosis. The following fibrosis algorithms were calculated: NAFLD fibrosis score, BARD, NIKEI, NASH-CRN regression score, APRI, FIB-4, King´s score, GUCI, Lok index, Forns score, and ELF. Study population was randomly divided in a training and a validation group. A multiple logistic regression analysis using bootstrapping methods was applied to the training group. Among many variables analyzed age, fasting glucose, hyaluronic acid and AST were included, and a model (LINKI-1) for predicting advanced fibrosis was created. Moreover, these variables were combined with platelet count in a mathematical way exaggerating the opposing effects, and alternative models (LINKI-2) were also created. Models were compared using area under the receiver operator characteristic curves (AUROC). Results Of established algorithms FIB-4 and King´s score had the best diagnostic accuracy with AUROCs 0.84 and 0.83, respectively. Higher accuracy was achieved with the novel LINKI algorithms. AUROCs in the total cohort for LINKI-1 was 0.91 and for LINKI-2 models 0.89. Conclusion The LINKI algorithms for detection of advanced fibrosis in NAFLD showed better accuracy than established algorithms and should be validated in further studies including larger cohorts. PMID:27936091

  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. 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

  17. Utilize conjugated melanotropins for the earlier diagnosis and treatment of Melanoma

    PubMed Central

    Cai, Minying; Liu, Zhonglin; Qu, Hongchang; Fan, Helen; Zheng, Zhiping; Hruby, Victor J.

    2011-01-01

    Peptides serve as effective drugs and the contrast agents in the clinic today. However the inherent drawbacks of peptide structures can limit their efficacy as drugs. To overcome this we have been developing new methods to create ‘tailor-made’ peptides and peptide mimetics with improved pharmacological and physical properties. In this work we introduce novel peptide and small molecule conjugated molecules for the earlier diagnosis and treatment of melanoma. PMID:21315067

  18. 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.

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

    SciTech Connect

    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 States 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.

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

    DOE PAGES

    Jiang, Bo; Liang, Shunlin; Ma, Han; ...

    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

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

    NASA Technical Reports Server (NTRS)

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

    1986-01-01

    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.

  2. 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

    During the first half of our second project year we have accomplished the following: (1) acquired a new AVHRR data set for the Beaufort Sea area spanning an entire year; (2) acquired additional ATSR data for the Arctic and Antarctic now totaling over seven months; (3) refined our AVHRR Arctic and Antarctic ice surface temperature (IST) retrieval algorithm, including work specific to Greenland; (4) developed ATSR retrieval algorithms for the Arctic and Antarctic, including work specific to Greenland; (5) investigated the effects of clouds and the atmosphere on passive microwave 'surface' temperature retrieval algorithms; (6) generated surface temperatures for the Beaufort Sea data set, both from AVHRR and SSM/I; and (7) continued work on compositing GAC data for coverage of the entire Arctic and Antarctic. During the second half of the year we will continue along these same lines, and will undertake a detailed validation study of the AVHRR and ATSR retrievals using LEADEX and the Beaufort Sea year-long data. Cloud masking methods used for the AVHRR will be modified for use with the ATSR. Methods of blending in situ and satellite-derived surface temperature data sets will be investigated.

  3. On developing B-spline registration algorithms for multi-core processors

    NASA Astrophysics Data System (ADS)

    Shackleford, J. A.; Kandasamy, N.; Sharp, G. C.

    2010-11-01

    Spline-based deformable registration methods are quite popular within the medical-imaging community due to their flexibility and robustness. However, they require a large amount of computing time to obtain adequate results. This paper makes two contributions towards accelerating B-spline-based registration. First, we propose a grid-alignment scheme and associated data structures that greatly reduce the complexity of the registration algorithm. Based on this grid-alignment scheme, we then develop highly data parallel designs for B-spline registration within the stream-processing model, suitable for implementation on multi-core processors such as graphics processing units (GPUs). Particular attention is focused on an optimal method for performing analytic gradient computations in a data parallel fashion. CPU and GPU versions are validated for execution time and registration quality. Performance results on large images show that our GPU algorithm achieves a speedup of 15 times over the single-threaded CPU implementation whereas our multi-core CPU algorithm achieves a speedup of 8 times over the single-threaded implementation. The CPU and GPU versions achieve near-identical registration quality in terms of RMS differences between the generated vector fields.

  4. Developing AEA system-of-systems mission plans with a multi-objective genetic algorithm

    NASA Astrophysics Data System (ADS)

    HandUber, Jason C.; Ridder, Jeffrey P.

    2007-04-01

    The role of an airborne electronic attack (AEA) system-of-systems (SoS) is to increase survivability of friendly aircraft by jamming hostile air defense radars. AEA systems are scarce, high-demand assets and have limited resources with which to engage a large number of radars. Given the limited resources, it is a significant challenge to plan their employment to achieve the desired results. Plans require specifying locations of jammers, as well as the mix of wide- and narrow-band jamming assignments delivered against particular radars. Further, the environment is uncertain as to the locations and emissions behaviors of radars. Therefore, we require plans that are not only capable, but also robust to the variability of the environment. In this paper, we use a multi-objective genetic algorithm to develop capable and robust AEA SoS mission plans. The algorithm seeks to determine the Pareto-front of three objectives - maximize the operational objectives achieved by friendly aircraft, minimize the threat to friendly aircraft, and minimize the expenditure of AEA assets. The results show that this algorithm is able to provide planners with the quantitative information necessary to intelligently construct capable and robust mission plans for an AEA SoS.

  5. 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.

  6. 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

  7. Development of an Algorithm Suite for MODIS and VIIRS Cloud Data Record Continuity

    NASA Astrophysics Data System (ADS)

    Platnick, S. E.; Holz, R.; Heidinger, A. K.; Ackerman, S. A.; Meyer, K.; Frey, R.; Wind, G.; Amarasinghe, N.

    2014-12-01

    The launch of Suomi NPP in the fall of 2011 began the next generation of the 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 (including emissivity), as well as multilayer cloud detection. In addition, there is a significant change in the spectral location of the 2.1 μm shortwave-infrared channel used by MODIS for cloud microphysical retrievals. The climate science community will face an interruption in the continuity of key global cloud data sets once the NASA EOS Terra and Aqua sensors cease operation. Given the instrument differences between MODIS EOS and VIIRS S-NPP/JPSS, we discuss methods for merging the 14+ year MODIS observational record with VIIRS/CrIS observations in order to generate cloud climate data record continuity across the observing systems. The main approach used by our team was to develop a cloud retrieval algorithm suite that is applied only to the common MODIS and VIIRS spectral channels. The suite uses heritage algorithms that produce the existing MODIS cloud mask (MOD35), MODIS cloud optical and microphysical properties (MOD06), and NOAA AWG/CLAVR-x cloud-top property products. Global monthly results from this hybrid algorithm suite (referred to as MODAWG) will be shown. Collocated CALIPSO comparisons will be shown that can independently evaluate inter-instrument product consistency for a subset of the MODAWG datasets.

  8. 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.

  9. Integrative multicellular biological modeling: a case study of 3D epidermal development using GPU algorithms

    PubMed Central

    2010-01-01

    Background Simulation of sophisticated biological models requires considerable computational power. These models typically integrate together numerous biological phenomena such as spatially-explicit heterogeneous cells, cell-cell interactions, cell-environment interactions and intracellular gene networks. The recent advent of programming for graphical processing units (GPU) opens up the possibility of developing more integrative, detailed and predictive biological models while at the same time decreasing the computational cost to simulate those models. Results We construct a 3D model of epidermal development and provide a set of GPU algorithms that executes significantly faster than sequential central processing unit (CPU) code. We provide a parallel implementation of the subcellular element method for individual cells residing in a lattice-free spatial environment. Each cell in our epidermal model includes an internal gene network, which integrates cellular interaction of Notch signaling together with environmental interaction of basement membrane adhesion, to specify cellular state and behaviors such as growth and division. We take a pedagogical approach to describing how modeling methods are efficiently implemented on the GPU including memory layout of data structures and functional decomposition. We discuss various programmatic issues and provide a set of design guidelines for GPU programming that are instructive to avoid common pitfalls as well as to extract performance from the GPU architecture. Conclusions We demonstrate that GPU algorithms represent a significant technological advance for the simulation of complex biological models. We further demonstrate with our epidermal model that the integration of multiple complex modeling methods for heterogeneous multicellular biological processes is both feasible and computationally tractable using this new technology. We hope that the provided algorithms and source code will be a starting point for modelers to

  10. 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.

  11. Development of an algorithm for automated enhancement of digital prototypes in machine engineering

    NASA Astrophysics Data System (ADS)

    Sokolova, E. A.; Dzhioev, G. A.

    2017-02-01

    The paper deals with the problem of processing digital prototypes in machine engineering with the use of modern approaches to computer vision, methods of taxonomy (a section of the decision theory), automation of manual retouching techniques. Upon further study of the problem, different taxonomic methods have been considered, among which the reference method has been chosen as the most appropriate for automated search of defective areas of the prototype. As a result, the algorithm for automated enhancement of digital prototypes of the digital image has been developed, using modern information technologies.

  12. 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.!

  13. 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.

  14. 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.

  15. 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.

  16. Earlier detection can help avoid many serious complications of peripartum cardiomyopathy.

    PubMed

    Fett, James D

    2013-11-01

    Peripartum cardiomyopathy (PPCM) has a remarkable potential for recovery. It may be within our capability to help almost all women with PPCM not only to survive, but also to completely recover heart function. Time-of-diagnosis left ventricular ejection fraction (LVEF) ≥0.35 is associated with better survival rates and higher full recovery rates. Increased mortality, chronic cardiomyopathy, thromboembolic complications and serious ventricular tachyarrhythmias are associated with diagnostic LVEF <0.30. Delays in diagnosis may result in lower LVEF at diagnosis and subsequent lower recovery rates. Greater awareness of the possibility of heart failure developing in previously healthy young women, with no history of heart disease, will contribute to earlier diagnosis, with potentially better preserved heart function. Women of African descent may be at higher risk for poorer outcomes. Recent investigations suggest newer biomarkers may help with earlier detection of PPCM.

  17. Algorithm development for intensity modulated continuous wave laser absorption spectrometry in atmospheric CO2 measurements

    NASA Astrophysics Data System (ADS)

    Lin, B.; Harrison, F. W.; Browell, E. V.; Dobler, J. T.; Bryant, R. B.

    2011-12-01

    Currently, NASA Langley Research Center (LaRC) and ITT are jointly developing algorithms for demonstration of range discrimination using ITT's laser absorption spectrometer (LAS), which is being evaluated for the future NASA Active Sensing of CO2 Emissions during Nights, Days, and Seasons (ASCENDS) mission. The objective of this Decadal Survey mission is to measure atmospheric column CO2 mixing ratios (XCO2) for improved determination of atmospheric carbon sources and sinks. Intensity Modulated Continuous Wave (IM-CW) techniques are used in this LAS approach. The LAS is designed to simultaneously measure CO2 and O2 columns, and these measurements are used to determine the required XCO2 column. The LAS measurements are enabled by the multi-channel operation of the instrument at 1.57 and 1.26-um for CO2 and O2, respectively. The algorithm development for the IM-CW techniques of the multi-channel LAS is focused on addressing key retrieval issues such as surface signal detection, thin cloud and/or aerosol layer rejection, vertical atmospheric range resolution, and optimizing the size of the measurement footprint. With these considerations, the modulation algorithm needs to maintain high enough signal-to-noise ratio (SNR) so that the mission scientific goals can be reached. A basic selection of the modulation algorithms that make XCO2 measurement and thin cloud rejection possible is the stepped frequency modulation scheme and a similar scheme of swept sine modulation. The differences between these two schemes for thin cloud rejection are small, assuming the proper selection of parameters is made. The stepped frequency approach is only a quantified version of swept sine method for the frequencies used. Swept sine scheme is a very common modulation technique for range discrimination, while the consideration of the stepped frequency scheme is based on the history of the rolling-tone modulation used in the instrument in previous successful column CO2 measurements. The

  18. Development of Elevation and Relief Databases for ICESat-2/ATLAS Receiver Algorithms

    NASA Astrophysics Data System (ADS)

    Leigh, H. W.; Magruder, L. A.; Carabajal, C. C.; Saba, J. L.; Urban, T. J.; Mcgarry, J.; Schutz, B. E.

    2013-12-01

    The Advanced Topographic Laser Altimeter System (ATLAS) is planned to launch onboard NASA's ICESat-2 spacecraft in 2016. ATLAS operates at a wavelength of 532 nm with a laser repeat rate of 10 kHz and 6 individual laser footprints. The satellite will be in a 500 km, 91-day repeat ground track orbit at an inclination of 92°. A set of onboard Receiver Algorithms has been developed to reduce the data volume and data rate to acceptable levels while still transmitting the relevant ranging data. The onboard algorithms limit the data volume by distinguishing between surface returns and background noise and selecting a small vertical region around the surface return to be included in telemetry. The algorithms make use of signal processing techniques, along with three databases, the Digital Elevation Model (DEM), the Digital Relief Map (DRM), and the Surface Reference Mask (SRM), to find the signal and determine the appropriate dynamic range of vertical data surrounding the surface for downlink. The DEM provides software-based range gating for ATLAS. This approach allows the algorithm to limit the surface signal search to the vertical region between minimum and maximum elevations provided by the DEM (plus some margin to account for uncertainties). The DEM is constructed in a nested, three-tiered grid to account for a hardware constraint limiting the maximum vertical range to 6 km. The DRM is used to select the vertical width of the telemetry band around the surface return. The DRM contains global values of relief calculated along 140 m and 700 m ground track segments consistent with a 92° orbit. The DRM must contain the maximum value of relief seen in any given area, but must be as close to truth as possible as the DRM directly affects data volume. The SRM, which has been developed independently from the DEM and DRM, is used to set parameters within the algorithm and select telemetry bands for downlink. Both the DEM and DRM are constructed from publicly available digital

  19. 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

  20. Development of algorithm for retrieving aerosols over land surfaces from NEMO-AM polarized measurements

    NASA Astrophysics Data System (ADS)

    Pandya, Mehul R.

    2016-04-01

    Atmospheric aerosols have a large effect on the Earth radiation budget through its direct and indirect effects. A systematic assessment of aerosol effects on Earth's climate requires global mapping of tropospheric aerosols through satellite remote sensing. However aerosol retrieval over land surface remains a challenging task due to bright background of the land surfaces. Polarized measurements can provide an improved aerosol sensing by providing a means of decoupling the surface and atmospheric contribution. The Indian Space Research Organisation has planned a Multi- Angle Dual-Polarization Instrument (MADPI) onboard a Nano satellite for Earth Monitoring & Observations for Aerosol Monitoring (NEMO-AM). MADPI has three spectral bands in blue, red and near infrared spectral regions with a nominal spatial resolution of 30 m from an altitude of 500 km polar orbit. A study has been taken up with the aim of development of an algorithm for retrieving aerosol optical thickness (AOT) over land surfaces from NEMO-AM polarized measurements. The study has three major components: (1) detailed theoretical modelling exercise for computing the atmospheric and surface polarized contributions, (2) modelling of total satellite-level polarized contribution, and (3) retrieval of aerosol optical thickness (AOT) by comparing the modelled and measured polarized signals. The algorithm has been developed for MADPI/NEMO-AM spectral bands and tested successfully on similar spectral bands of POLDER/PARASOL measurements to retrieve AOT over Indian landmass having diverse atmospheric conditions. POLDER-derived AOT fields were compared with MODIS-AOT products. Results showed a very good match (R2 0.69, RMSE 0.07). Initial results have provided encouraging results, however, comprehensive analysis and testing has to be carried out for establishing the proposed algorithm for retrieving AOT from NEMO-AM measurements.

  1. 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.

  2. 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.

  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 a Detection Algorithm for Use with Reflectance-Based, Real-Time Chemical Sensing

    PubMed Central

    Malanoski, Anthony P.; Johnson, Brandy J.; Erickson, Jeffrey S.; Stenger, David A.

    2016-01-01

    Here, we describe our efforts focused on development of an algorithm for identification of detection events in a real-time sensing application relying on reporting of color values using commercially available color sensing chips. The effort focuses on the identification of event occurrence, rather than target identification, and utilizes approaches suitable to onboard device incorporation to facilitate portable and autonomous use. The described algorithm first excludes electronic noise generated by the sensor system and determines response thresholds. This automatic adjustment provides the potential for use with device variations as well as accommodating differing indicator behaviors. Multiple signal channels (RGB) as well as multiple indicator array elements are combined for reporting of an event with a minimum of false responses. While the method reported was developed for use with paper-supported porphyrin and metalloporphyrin indicators, it should be equally applicable to other colorimetric indicators. Depending on device configurations, receiver operating characteristic (ROC) sensitivities of 1 could be obtained with specificities of 0.87 (threshold 160 ppb, ethanol). PMID:27854335

  5. 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.

  6. 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

  7. 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.

  8. Collaboration on Development and Validation of the AMSR-E Snow Water Equivalent Algorithm

    NASA Technical Reports Server (NTRS)

    Armstrong, Richard L.

    2000-01-01

    The National Snow and Ice Data Center (NSIDC) has produced a global SMMR and SSM/I Level 3 Brightness Temperature data set in the Equal Area Scalable Earth (EASE) Grid for the period 1978 to 2000. Processing of current data is-ongoing. The EASE-Grid passive microwave data sets are appropriate for algorithm development and validation prior to the launch of AMSR-E. Having the lower frequency channels of SMMR (6.6 and 10.7 GHz) and the higher frequency channels of SSM/I (85.5 GHz) in the same format will facilitate the preliminary development of applications which could potentially make use of similar frequencies from AMSR-E (6.9, 10.7, 89.0 GHz).

  9. Development of a New De Novo Design Algorithm for Exploring Chemical Space.

    PubMed

    Mishima, Kazuaki; Kaneko, Hiromasa; Funatsu, Kimito

    2014-12-01

    In the first stage of development of new drugs, various lead compounds with high activity are required. To design such compounds, we focus on chemical space defined by structural descriptors. New compounds close to areas where highly active compounds exist will show the same degree of activity. We have developed a new de novo design system to search a target area in chemical space. First, highly active compounds are manually selected as initial seeds. Then, the seeds are entered into our system, and structures slightly different from the seeds are generated and pooled. Next, seeds are selected from the new structure pool based on the distance from target coordinates on the map. To test the algorithm, we used two datasets of ligand binding affinity and showed that the proposed generator could produce diverse virtual compounds that had high activity in docking simulations.

  10. Development of a Machine Learning Algorithm for the Surveillance of Autism Spectrum Disorder

    PubMed Central

    Maenner, Matthew J.; Yeargin-Allsopp, Marshalyn; Van Naarden Braun, Kim; Christensen, Deborah L.; Schieve, Laura A.

    2016-01-01

    The Autism and Developmental Disabilities Monitoring (ADDM) Network conducts population-based surveillance of autism spectrum disorder (ASD) among 8-year old children in multiple US sites. To classify ASD, trained clinicians review developmental evaluations collected from multiple health and education sources to determine whether the child meets the ASD surveillance case criteria. The number of evaluations collected has dramatically increased since the year 2000, challenging the resources and timeliness of the surveillance system. We developed and evaluated a machine learning approach to classify case status in ADDM using words and phrases contained in children’s developmental evaluations. We trained a random forest classifier using data from the 2008 Georgia ADDM site which included 1,162 children with 5,396 evaluations (601 children met ADDM ASD criteria using standard ADDM methods). The classifier used the words and phrases from the evaluations to predict ASD case status. We evaluated its performance on the 2010 Georgia ADDM surveillance data (1,450 children with 9,811 evaluations; 754 children met ADDM ASD criteria). We also estimated ASD prevalence using predictions from the classification algorithm. Overall, the machine learning approach predicted ASD case statuses that were 86.5% concordant with the clinician-determined case statuses (84.0% sensitivity, 89.4% predictive value positive). The area under the resulting receiver-operating characteristic curve was 0.932. Algorithm-derived ASD “prevalence” was 1.46% compared to the published (clinician-determined) estimate of 1.55%. Using only the text contained in developmental evaluations, a machine learning algorithm was able to discriminate between children that do and do not meet ASD surveillance criteria at one surveillance site. PMID:28002438

  11. Artificial lightning data as proxy data for the algorithm development for the geostationary lightning imager

    NASA Astrophysics Data System (ADS)

    Finke, U.

    2009-12-01

    The geostationary Meteosat Third Generation (MTG) will carry the Lightning Imager (LI) for the detection and location of the total lightning by optical means. The Lightning Imager will continuously observe the full visible disk and provide lightning data with high uniformity over land and ocean during day and night. Its main operational applications are the nowcasting of severe storms and the warning of lightning strike threat. For the development of the data processor prototype a proxy data set is necessary as a reference data set in order to prove the function of the algorithms under the expected observation conditions. Additionally, a set of proxy data simulating the optical pulses originating from lightning can be used to optimize the performance of the detecting instrument. This contribution presents the methodology and the results of the generation of artificial lightning data. The artificial data set is created by random number generators which produces data obeying the same statistical distribution characteristics as real data. The generator bases on the empirical distribution density functions of the lightning characteristics which were derived from optical lightning observations by low orbit satellites (LIS) and ground based observations of lightning. The resulting artificial data represent optical lightning pulses as seen on the upper cloud surface. They are characterized by their distribution on three scales: the distribution of photons in a single lightning pulse, the distribution of lightning flashes in a single storm and the distribution of storms on the globe. The artificial data are used as input for the data processing and product generating algorithms. The elementary product of the lightning imager are the detected lightning pulses with their time, location and optical energy. These data are the basis for the generation of the various meteorological products such as lightning densities in geographical areas, storm cells with their motion

  12. 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.

  13. A prototype hail detection algorithm and hail climatology developed with the advanced microwave sounding unit (AMSU)

    NASA Astrophysics Data System (ADS)

    Ferraro, Ralph; Beauchamp, James; Cecil, Daniel; Heymsfield, Gerald

    2015-09-01

    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 Scanning Multichannel Microwave Radiometer (SMMR), the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and most recently, the Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sensor. This led to climatologies of hail frequency from TMI and AMSR-E, however, limitations included 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. NOAA and EUMETSAT have been operating the Advanced Microwave Sounding Unit (AMSU-A and -B) and the Microwave Humidity Sounder (MHS) on several operational satellites since 1998: 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 h, thus, offering a much larger time and temporal sampling than TRMM or AMSR-E. With similar observation frequencies near 30 and 85 GHz, one at 157 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 US for a 10-year period (2000-2009). Compared with the surface observations, the algorithm detects approximately 40% of hail occurrences. The simple threshold algorithm is then used to generate a hail climatology based on all available AMSU observations during 2000-2011 that is stratified in several ways

  14. 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

  15. DEVELOPMENT AND TESTING OF FAULT-DIAGNOSIS ALGORITHMS FOR REACTOR PLANT SYSTEMS

    SciTech Connect

    Grelle, Austin L.; Park, Young S.; Vilim, Richard B.

    2016-06-26

    Argonne National Laboratory is further developing fault diagnosis algorithms for use by the operator of a nuclear plant to aid in improved monitoring of overall plant condition and performance. The objective is better management of plant upsets through more timely, informed decisions on control actions with the ultimate goal of improved plant safety, production, and cost management. Integration of these algorithms with visual aids for operators is taking place through a collaboration under the concept of an operator advisory system. This is a software entity whose purpose is to manage and distill the enormous amount of information an operator must process to understand the plant state, particularly in off-normal situations, and how the state trajectory will unfold in time. The fault diagnosis algorithms were exhaustively tested using computer simulations of twenty different faults introduced into the chemical and volume control system (CVCS) of a pressurized water reactor (PWR). The algorithms are unique in that each new application to a facility requires providing only the piping and instrumentation diagram (PID) and no other plant-specific information; a subject-matter expert is not needed to install and maintain each instance of an application. The testing approach followed accepted procedures for verifying and validating software. It was shown that the code satisfies its functional requirement which is to accept sensor information, identify process variable trends based on this sensor information, and then to return an accurate diagnosis based on chains of rules related to these trends. The validation and verification exercise made use of GPASS, a one-dimensional systems code, for simulating CVCS operation. Plant components were failed and the code generated the resulting plant response. Parametric studies with respect to the severity of the fault, the richness of the plant sensor set, and the accuracy of sensors were performed as part of the validation

  16. 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

  17. 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.

  18. 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

  19. 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.

  20. Development of a computer algorithm for feedback controlled electrical nerve fiber stimulation.

    PubMed

    Doruk, R Özgür

    2011-09-01

    The purpose of this research is to develop an algorithm for a feedback controlled local electrical nerve fiber stimulation system which has the purpose to stop the repetitive firing in a particular region of the nervous system. The electrophysiological behavior of the neurons (under electrical currents) is modeled by Hodgkin-Huxley (HH) type nonlinear nerve fiber dynamics. The repetitive firing of in the modeled fiber is due to the deviations in the channel parameters, which is also called as bifurcation in the nonlinear systems theory. A washout filter is augmented to the HH dynamics and then the output of the filter is fed to the external current generator through a linear gain. This gain is computed by linear projective control theory. That is a linear output feedback control technique where the closed loop spectrum of the full state feedback closed loop is partially maintained. By obtaining a spectrum of eigenvalues with completely negative real parts the nerve fibers can be relaxed to the equilibrium point with or without a damped oscillation. The MATLAB script applying the theory of this work is provided at the end of this paper. A MATLAB-Simulink computer simulation is performed in order to verify the algorithm.

  1. 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

  2. Further development of image processing algorithms to improve detectability of defects in Sonic IR NDE

    NASA Astrophysics Data System (ADS)

    Obeidat, Omar; Yu, Qiuye; Han, Xiaoyan

    2017-02-01

    Sonic Infrared imaging (SIR) technology is a relatively new NDE technique that has received significant acceptance in the NDE community. SIR NDE is a super-fast, wide range NDE method. The technology uses short pulses of ultrasonic excitation together with infrared imaging to detect defects in the structures under inspection. Defects become visible to the IR camera when the temperature in the crack vicinity increases due to various heating mechanisms in the specimen. Defect detection is highly affected by noise levels as well as mode patterns in the image. Mode patterns result from the superposition of sonic waves interfering within the specimen during the application of sound pulse. Mode patterns can be a serious concern, especially in composite structures. Mode patterns can either mimic real defects in the specimen, or alternatively, hide defects if they overlap. In last year's QNDE, we have presented algorithms to improve defects detectability in severe noise. In this paper, we will present our development of algorithms on defect extraction targeting specifically to mode patterns in SIR images.

  3. 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.

  4. Development of a neonate lung reconstruction algorithm using a wavelet AMG and estimated boundary form.

    PubMed

    Bayford, R; Kantartzis, P; Tizzard, A; Yerworth, R; Liatsis, P; Demosthenous, A

    2008-06-01

    Objective, non-invasive measures of lung maturity and development, oxygen requirements and lung function, suitable for use in small, unsedated infants, are urgently required to define the nature and severity of persisting lung disease, and to identify risk factors for developing chronic lung problems. Disorders of lung growth, maturation and control of breathing are among the most important problems faced by the neonatologists. At present, no system for continuous monitoring of neonate lung function to reduce the risk of chronic lung disease in infancy in intensive care units exists. We are in the process of developing a new integrated electrical impedance tomography (EIT) system based on wearable technology to integrate measures of the boundary diameter from the boundary form for neonates into the reconstruction algorithm. In principle, this approach could provide a reduction of image artefacts in the reconstructed image associated with incorrect boundary form assumptions. In this paper, we investigate the required accuracy of the boundary form that would be suitable to minimize artefacts in the reconstruction for neonate lung function. The number of data points needed to create the required boundary form is automatically determined using genetic algorithms. The approach presented in this paper is to assist quality of the reconstruction using different approximations to the ideal boundary form. We also investigate the use of a wavelet algebraic multi-grid (WAMG) preconditioner to reduce the reconstruction computation requirements. Results are presented that demonstrate a full 3D model is required to minimize artefact in the reconstructed image and the implementation of a WAMG for EIT.

  5. Cutaneous malignancies in xeroderma pigmentosum: earlier management improves survival.

    PubMed

    Naik, Sudhir M; Shenoy, Ashok M; Nanjundappa, A; Halkud, Rajshekar; Chavan, Purshottam; Sidappa, K; Gupta, Sumit

    2013-04-01

    Xeroderma pigmentosum (XP) is a rare autosomal recessive disease, characterized by hypersensitivity of the skin to ultraviolet (UV) radiation leading to high incidence of skin cancer and progressive neurological complications. It results in premature development of neoplasias due to an exacerbated hypersensitivity to UV radiation causing premalignant and malignant lesions leading to death in early adulthood. Two cases of clinical features of xeroderma pigmentosa with skin lesions were managed in our department. One had multiple clusters of basal and squamous cell carcinomas and the other had malignant melanomas and right neck nodes. Both were treated with multiple wide excisions and the neck node were surgically managed with radical neck dissections. Skin malignancies were common in the sun exposed areas and patients were advised regular 3 months follow up. The disease is ultimately fatal, life can be prolonged by simple preventive measures to minimize sun exposure. Comprehensive multimodality management includes patient education and counselling for the psychosomatic disorder and genetic counseling remains the most important preventive measure.

  6. 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

  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. Development of algorithms for detection of mechanical injury on white mushrooms (Agaricus bisporus) using hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Gowen, A. A.; O'Donnell, C. P.

    2009-05-01

    White mushrooms were subjected to mechanical injury by controlled shaking in a plastic box at 400 rpm for different times (0, 60, 120, 300 and 600 s). Immediately after shaking, hyperspectral images were obtained using two pushbroom line-scanning hyperspectral imaging instruments, one operating in the wavelength range of 400 - 1000 nm with spectroscopic resolution of 5 nm, the other operating in the wavelength range of 950 - 1700 nm with spectroscopic resolution of 7 nm. Different spectral and spatial pretreatments were investigated to reduce the effect of sample curvature on hyperspectral data. Algorithms based on Chemometric techniques (Principal Component Analysis and Partial Least Squares Discriminant Analysis) and image processing methods (masking, thresholding, morphological operations) were developed for pixel classification in hyperspectral images. In addition, correlation analysis, spectral angle mapping and scaled difference of sample spectra were investigated and compared with the chemometric approaches.

  9. 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.

  10. Soft sensor development for Mooney viscosity prediction in rubber mixing process based on GMMDJITGPR algorithm

    NASA Astrophysics Data System (ADS)

    Yang, Kai; Chen, Xiangguang; Wang, Li; Jin, Huaiping

    2017-01-01

    In rubber mixing process, the key parameter (Mooney viscosity), which is used to evaluate the property of the product, can only be obtained with 4-6h delay offline. It is quite helpful for the industry, if the parameter can be estimate on line. Various data driven soft sensors have been used to prediction in the rubber mixing. However, it always not functions well due to the phase and nonlinear property in the process. The purpose of this paper is to develop an efficient soft sensing algorithm to solve the problem. Based on the proposed GMMD local sample selecting criterion, the phase information is extracted in the local modeling. Using the Gaussian local modeling method within Just-in-time (JIT) learning framework, nonlinearity of the process is well handled. Efficiency of the new method is verified by comparing the performance with various mainstream soft sensors, using the samples from real industrial rubber mixing process.

  11. 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.

  12. 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.

  13. Developing image processing meta-algorithms with data mining of multiple metrics.

    PubMed

    Leung, Kelvin; 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.

  14. 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.

  15. 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

  16. A basis for the development of operational algorithms for simplified GPS integrity checking

    NASA Astrophysics Data System (ADS)

    Parkinson, Bradford W.; Axelrad, Penina

    Error models are developed for a least squares approach to GPS satellite failure detection, and a statistical analysis is presented. The algorithm assumes that the GPS user forms a navigation solution by performing a least squares fit to pseudorange measurements made to five or more satellites in view. Results for a C/A code receiver show that a nominal pseudorange measurement error can be realistically modelled as a normally distributed random variable with a mean ranging from -5 to +5 and a standard deviation of 0.4 m for Doppler aided, and 4.0 m for code only, measurements. Theoretical success rates are presented for specific user geometries and measurement errors.

  17. 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

  18. 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.

  19. 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.

  20. The development and concurrent validity of a real-time algorithm for temporal gait analysis using inertial measurement units.

    PubMed

    Allseits, E; Lučarević, J; Gailey, R; Agrawal, V; Gaunaurd, I; Bennett, C

    2017-04-11

    The use of inertial measurement units (IMUs) for gait analysis has emerged as a tool for clinical applications. Shank gyroscope signals have been utilized to identify heel-strike and toe-off, which serve as the foundation for calculating temporal parameters of gait such as single and double limb support time. Recent publications have shown that toe-off occurs later than predicted by the dual minima method (DMM), which has been adopted as an IMU-based gait event detection algorithm.In this study, a real-time algorithm, Noise-Zero Crossing (NZC), was developed to accurately compute temporal gait parameters. Our objective was to determine the concurrent validity of temporal gait parameters derived from the NZC algorithm against parameters measured by an instrumented walkway. The accuracy and precision of temporal gait parameters derived using NZC were compared to those derived using the DMM. The results from Bland-Altman Analysis showed that the NZC algorithm had excellent agreement with the instrumented walkway for identifying the temporal gait parameters of Gait Cycle Time (GCT), Single Limb Support (SLS) time, and Double Limb Support (DLS) time. By utilizing the moment of zero shank angular velocity to identify toe-off, the NZC algorithm performed better than the DMM algorithm in measuring SLS and DLS times. Utilizing the NZC algorithm's gait event detection preserves DLS time, which has significant clinical implications for pathologic gait assessment.

  1. 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

  2. An earlier age of breast cancer diagnosis related to more frequent use of antiperspirants/deodorants and underarm shaving.

    PubMed

    McGrath, K G

    2003-12-01

    Breast cancer incidence suggests a lifestyle cause. A lifestyle factor used near the breast is the application of antiperspirants/deodorants accompanied by axillary shaving. A previous study did not support a link with breast cancer. If these habits have a role in breast cancer development, women using antiperspirants/deodorants and shaving their underarms frequently would be expected to have an earlier age of diagnosis than those doing so less often. An earlier age of diagnosis would also be expected in those starting to use deodorants and shaving at an earlier age. This is the first study to investigate the intensity of underarm exposure in a cohort of breast cancer survivors. Four hundred and thirty-seven females diagnosed with breast cancer were surveyed. Once grouped by their frequency of underarm hygiene habits, the mean age of diagnosis was the primary end point. Secondary end points included the overall frequency of these habits, and potential usage group confounding variables were evaluated. All statistical tests were two-sided. Frequency and earlier onset of antiperspirant/deodorant usage with underarm shaving were associated with an earlier age of breast cancer diagnosis. Combined habits are likely for this earlier age of diagnosis. In conclusion, underarm shaving with antiperspirant/deodorant use may play a role in breast cancer. It is not clear which of these components are involved. Reviewed literature insinuates absorption of aluminium salts facilitated by dermal barrier disruption. Case-controlled investigations are needed before alternative underarm hygiene habits are suggested.

  3. Prediction system of hydroponic plant growth and development using algorithm Fuzzy Mamdani method

    NASA Astrophysics Data System (ADS)

    Sudana, I. Made; Purnawirawan, Okta; Arief, Ulfa Mediaty

    2017-03-01

    Hydroponics is a method of farming without soil. One of the Hydroponic plants is Watercress (Nasturtium Officinale). The development and growth process of hydroponic Watercress was influenced by levels of nutrients, acidity and temperature. The independent variables can be used as input variable system to predict the value level of plants growth and development. The prediction system is using Fuzzy Algorithm Mamdani method. This system was built to implement the function of Fuzzy Inference System (Fuzzy Inference System/FIS) as a part of the Fuzzy Logic Toolbox (FLT) by using MATLAB R2007b. FIS is a computing system that works on the principle of fuzzy reasoning which is similar to humans' reasoning. Basically FIS consists of four units which are fuzzification unit, fuzzy logic reasoning unit, base knowledge unit and defuzzification unit. In addition to know the effect of independent variables on the plants growth and development that can be visualized with the function diagram of FIS output surface that is shaped three-dimensional, and statistical tests based on the data from the prediction system using multiple linear regression method, which includes multiple linear regression analysis, T test, F test, the coefficient of determination and donations predictor that are calculated using SPSS (Statistical Product and Service Solutions) software applications.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. Development and evaluation of a micro-macro algorithm for the simulation of polymer flow

    SciTech Connect

    Feigl, Kathleen . E-mail: feigl@mtu.edu; Tanner, Franz X.

    2006-07-20

    A micro-macro algorithm for the calculation of polymer flow is developed and numerically evaluated. The system being solved consists of the momentum and mass conservation equations from continuum mechanics coupled with a microscopic-based rheological model for polymer stress. Standard finite element techniques are used to solve the conservation equations for velocity and pressure, while stochastic simulation techniques are used to compute polymer stress from the simulated polymer dynamics in the rheological model. The rheological model considered combines aspects of reptation, network and continuum models. Two types of spatial approximation are considered for the configuration fields defining the dynamics in the model: piecewise constant and piecewise linear. The micro-macro algorithm is evaluated by simulating the abrupt planar die entry flow of a polyisobutylene solution described in the literature. The computed velocity and stress fields are found to be essentially independent of mesh size and ensemble size, while there is some dependence of the results on the order of spatial approximation to the configuration fields close to the die entry. Comparison with experimental data shows that the piecewise linear approximation leads to better predictions of the centerline first normal stress difference. Finally, the computational time associated with the piecewise constant spatial approximation is found to be about 2.5 times lower than that associated with the piecewise linear approximation. This is the result of the more efficient time integration scheme that is possible with the former type of approximation due to the pointwise incompressibility guaranteed by the choice of velocity-pressure finite element.

  10. 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

  11. 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…

  12. 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

  13. 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

  14. Development of multi-objective genetic algorithm concurrent subspace optimization (MOGACSSO) method with robustness

    NASA Astrophysics Data System (ADS)

    Parashar, Sumeet

    Most engineering design problems are complex and multidisciplinary in nature, and quite often require more than one objective (cost) function to be extremized simultaneously. For multi-objective optimization problems, there is not a single optimum solution, but a set of optimum solutions called the Pareto set. The primary goal of this research is to develop a heuristic solution strategy to enable multi-objective optimization of highly coupled multidisciplinary design applications, wherein each discipline is able to retain some degree of autonomous control during the process. To achieve this goal, this research extends the capability of the Multi-Objective Pareto Concurrent Subspace Optimization (MOPCSSO) method to generate large numbers of non-dominated solutions in each cycle, with subsequent update and refinement, thereby greatly increasing efficiency. While the conventional MOPCSSO approach is easily able to generate Pareto solutions, it will only generate one Pareto solution at a time. In order to generate the complete Pareto front, MOPCSSO requires multiple runs (translating into many system convergence cycles) using different initial staring points. In this research, a Genetic Algorithm-based heuristic solution strategy is developed for multi-objective problems in coupled multidisciplinary design. The Multi-Objective Genetic Algorithm Concurrent Subspace Optimization (MOGACSSO) method allows for the generation of relatively evenly distributed Pareto solutions in a faster and more efficient manner than repeated implementation of MOPCSSO. While achieving an optimum design, it is often also desirable that the optimum design be robust to uncontrolled parameter variations. In this research, the capability of the MOGACSSO method is also extended to generate Pareto points that are robust in terms of performance and feasibility, for given uncontrolled parameter variations. The Roust-MOGACSSO method developed in this research can generate a large number of designs

  15. Development of algorithms and approximations for rapid operational air quality modelling

    NASA Astrophysics Data System (ADS)

    Barrett, Steven R. H.; Britter, Rex E.

    In regulatory and public health contexts the long-term average pollutant concentration in the vicinity of a source is frequently of interest. Well-developed modelling tools such as AERMOD and ADMS are able to generate time-series air quality estimates of considerable accuracy, applying an up-to-date understanding of atmospheric boundary layer behaviour. However, such models incur a significant computational cost with runtimes of hours to days. These approaches are often acceptable when considering a single industrial complex, but for widespread policy analyses the computational cost rapidly becomes intractable. In this paper we present some mathematical techniques and algorithmic approaches that can make air quality estimates several orders of magnitude faster. We show that, for long-term average concentrations, lateral dispersion need not be accounted for explicitly. This is applied to a simple reference case of a ground-level point source in a neutral boundary layer. A scaling law is also developed for the area in exceedance of a regulatory limit value.

  16. Design and development of guidance navigation and control algorithms for spacecraft rendezvous and docking experimentation

    NASA Astrophysics Data System (ADS)

    Guglieri, Giorgio; Maroglio, Franco; Pellegrino, Pasquale; Torre, Liliana

    2014-01-01

    This paper presents the design of the GNC system of a ground test-bed for spacecraft rendezvous and docking experiments. The test-bed is developed within the STEPS project (Systems and Technologies for Space Exploration). The facility consists of a flat floor and two scaled vehicles, one active chaser and one “semi-active” target. Rendezvous and docking maneuvers are performed floating on the plane with pierced plates as lifting systems. The system is designed to work both with inertial and non-inertial reference frame, receiving signals from navigation sensors as: accelerometers, gyroscopes, laser meter, radio finder and video camera, and combining them with a digital filter. A Proportional-Integrative-Derivative control law and Pulse Width Modulators are used to command the cold gas thrusters of the chaser, and to follow an assigned trajectory with its specified velocity profile. The design and development of the guidance, navigation and control system and its architecture-including the software algorithms-are detailed in the paper, presenting a performance analysis based on a simulated environment. A complete description of the integrated subsystems is also presented.

  17. 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.

  18. Development of a Robotic Colonoscopic Manipulation System, Using Haptic Feedback Algorithm

    PubMed Central

    Woo, Jaehong; Choi, Jae Hyuk; Seo, Jong Tae

    2017-01-01

    Purpose Colonoscopy is one of the most effective diagnostic and therapeutic tools for colorectal diseases. We aim to propose a master-slave robotic colonoscopy that is controllable in remote site using conventional colonoscopy. Materials and Methods The master and slave robot were developed to use conventional flexible colonoscopy. The robotic colonoscopic procedure was performed using a colonoscope training model by one expert endoscopist and two unexperienced engineers. To provide the haptic sensation, the insertion force and the rotating torque were measured and sent to the master robot. Results A slave robot was developed to hold the colonoscopy and its knob, and perform insertion, rotation, and two tilting motions of colonoscope. A master robot was designed to teach motions of the slave robot. These measured force and torque were scaled down by one tenth to provide the operator with some reflection force and torque at the haptic device. The haptic sensation and feedback system was successful and helpful to feel the constrained force or torque in colon. The insertion time using robotic system decreased with repeated procedures. Conclusion This work proposed a robotic approach for colonoscopy using haptic feedback algorithm, and this robotic device would effectively perform colonoscopy with reduced burden and comparable safety for patients in remote site. PMID:27873506

  19. 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

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

    NASA Technical Reports Server (NTRS)

    Gordon, Howard R.

    1994-01-01

    During CY 1994 there are five objectives under this task: (1) investigate the effects of stratospheric aerosol on the proposed correction algorithm, and investigate the use of the 1380 nm MODIS band to remove the stratospheric aerosol perturbation; (2) investigate the effect of vertical structure in aerosol concentration and type on the behavior of the proposed correction algorithm; (3) investigate the effects of polarization on the accuracy of the algorithm; (4) improve the accuracy and speed of the existing algorithm; and (5) investigate removal of the O2 'A' absorption band at 762 nm from the 765 nm SeaWiFS band so the latter can be used in atmospheric correction of SeaWiFS. The importance of this to MODIS is that SeaWiFS data will be used extensively to test and improve the MODIS algorithm. Thus it is essential that the O2 absorption be adequately dealt with for SeaWiFS.

  1. 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

  2. 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

  3. Higher Sensitivity and Earlier Identification of Celiac Disease Autoimmunity by a Nonradioactive Assay for Transglutaminase Autoantibodies

    PubMed Central

    Zhao, Zhiyuan; Miao, Dongmei; Waugh, Kathleen; Taki, Iman; Dong, Fran; Liu, Edwin

    2016-01-01

    Higher sensitive transglutaminase autoantibody (TGA) assay will detect the onset of celiac disease (CD) autoimmunity earlier. In developing a nonradioactive assay for TGA, we utilized electrochemiluminescence (ECL) technology and compared it to a high-performance radioimmunoassay (RIA) currently being used to screen patients with type 1 diabetes (T1D) and genetically at-risk individuals for CD. We selected 183 T1D patients with 60 patients having received biopsy and analyzed 396 sequential samples from 73 young children longitudinally followed up with TGA seroconversion, with 27 undergoing biopsy. In addition, 112 age-matched healthy control subjects were included in the study. With the 99th percentile of specificity, the ECL assay detected significantly more TGA positivity among patients with T1D (133/183) than RIA (114/183) and more of the sequential samples (34%) from 73 children than RIA (18%). The TGA assay performed by ECL was positive in all 59 subjects with villous atrophy. Among 73 longitudinally followed up children, ECL assay had earlier detection of TGA on 34 children by a mean of 2.5 years. In conclusion, the new TGA assay by ECL has a higher sensitivity than the current RIA assay and may better predict the onset of CD. PMID:28127566

  4. Ontogenic changes rather than difference in temperature cause understory trees to leaf out earlier.

    PubMed

    Vitasse, Yann

    2013-04-01

    In a temperate climate, understory trees leaf out earlier than canopy trees, but the cause of this discrepancy remains unclear. This study aims to investigate whether this discrepancy results from ontogenic changes or from microclimatic differences. Seedlings of five deciduous tree species were grown in spring 2012 in the understory and at canopy height using a 45-m-high construction crane built into a mature mixed forest in the foothills of the Swiss Jura Mountains. The leaf development of these seedlings, as well as conspecific adults, was compared, taking into account the corresponding microclimate. The date of leaf unfolding occurred 10-40 d earlier in seedlings grown at canopy level than in conspecific adults. Seedlings grown in the understory flushed c. 6 d later than those grown at canopy height, which can be attributed to the warmer temperatures recorded at canopy height (c. 1°C warmer). This study demonstrates that later leaf emergence of canopy trees compared with understory trees results from ontogenic changes and not from the vertical thermal profile that exists within forests. This study warns against the assumption that phenological data obtained in warming and photoperiod experiments on juvenile trees can be used for the prediction of forest response to climate warming.

  5. 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.

  6. Development and validation of algorithms for heart failure patient care: a Delphi study

    PubMed Central

    Gopal, Cynthia Priyadarshini; Ranga, Asri; Joseph, Kevin Louis; Tangiisuran, Balamurugan

    2015-01-01

    INTRODUCTION Although heart failure (HF) management is available at primary and secondary care facilities in Malaysia, the optimisation of drug therapy is still suboptimal. Although pharmacists can help bridge the gap in optimising HF therapy, pharmacists in Malaysia currently do not manage and titrate HF pharmacotherapy. The aim of this study was to develop treatment algorithms and monitoring protocols for angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers and spironolactone based on extensive literature review for validation and utilisation by pharmacists involved in HF management. METHODS A Delphi survey involving 32 panellists from private and government hospitals that provide cardiac services in Malaysia was conducted to obtain a consensus of opinion on the treatment protocols. The panellists completed two rounds of self-administered questionnaires to determine their level of agreement with all the components in the protocols. RESULTS Consensus was achieved for most of the sections of the protocols for the four classes of drugs. The panellists’ opinions were taken into consideration when amending the components of the protocols that did not achieve consensus of opinion. Full consensus was achieved with the second survey conducted, enabling the finalisation of the drug titration protocols. CONCLUSION The resulting validated HF titration protocols can be used as a guide for pharmacists when recommending the initiation and titration of HF drug therapy in daily clinical practice. Recommendations should be made in collaboration with the patient’s treating physician, with concomitant monitoring of the patient’s response to the drugs. PMID:25532514

  7. Development of Pressurized Water Reactor Integrated Safety Analysis Methodology Using Multilevel Coupling Algorithm

    SciTech Connect

    Ziabletsev, Dmitri; Avramova, Maria; Ivanov, Kostadin

    2004-11-15

    The subchannel code COBRA-TF has been introduced for an evaluation of thermal margins on the local pin-by-pin level in a pressurized water reactor. The coupling of COBRA-TF with TRAC-PF1/NEM is performed by providing from TRAC to COBRA-TF axial and radial thermal-hydraulic boundary conditions and relative pin-power profiles, obtained with the pin power reconstruction model of the nodal expansion method (NEM). An efficient algorithm for coupling of the subchannel code COBRA-TF with TRAC-PF1/NEM in the parallel virtual machine environment was developed addressing the issues of time synchronization, data exchange, spatial overlays, and coupled convergence. Local feedback modeling on the pin level was implemented into COBRA-TF, which enabled updating the local form functions and the recalculation of the pin powers in TRAC-PF1/NEM after obtaining the local feedback parameters. The coupled TRAC-PF1/NEM/COBRA-TF code system was tested on the rod ejection accident and main steam line break benchmark problems. In both problems, the local results are closer than before the introduced multilevel coupling to the corresponding critical limits. This fact indicates that the assembly average results tend to underestimate the accident consequences in terms of local safety margins. The capability of local safety evaluation, performed simultaneously (online) with coupled global three-dimensional neutron kinetics/thermal-hydraulic calculations, is introduced and tested. The obtained results demonstrate the importance of the current work.

  8. 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.

  9. 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

  10. 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

  11. Informing radar retrieval algorithm development using an alternative soil moisture validation technique

    NASA Astrophysics Data System (ADS)

    Crow, W. T.; Wagner, W.

    2009-12-01

    incidence angle on retrieval skill. Results imply the need for a significant interaction term in vegetation backscatter models in order to match the observed relationship between incidence angle and retrieval skill. Implications for the development of radar retrieval algorithms for the NASA Soil Moisture Active/Passive (SMAP) mission will be discussed.

  12. 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.

  13. 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...

  14. Development of Turbulent Diffusion Transfer Algorithms to Estimate Lake Tahoe Water Budget

    NASA Astrophysics Data System (ADS)

    Sahoo, G. B.; Schladow, S. G.; Reuter, J. E.

    2012-12-01

    The evaporative loss is a dominant component in the Lake Tahoe hydrologic budget because watershed area (813km2) is very small compared to the lake surface area (501 km2). The 5.5 m high dam built at the lake's only outlet, the Truckee River at Tahoe City can increase the lake's capacity by approximately 0.9185 km3. The lake serves as a flood protection for downstream areas and source of water supply for downstream cities, irrigation, hydropower, and instream environmental requirements. When the lake water level falls below the natural rim, cessation of flows from the lake cause problems for water supply, irrigation, and fishing. Therefore, it is important to develop algorithms to correctly estimate the lake hydrologic budget. We developed a turbulent diffusion transfer model and coupled to the dynamic lake model (DLM-WQ). We generated the stream flows and pollutants loadings of the streams using the US Environmental Protection Agency (USEPA) supported watershed model, Loading Simulation Program in C++ (LSPC). The bulk transfer coefficients were calibrated using correlation coefficient (R2) as the objective function. Sensitivity analysis was conducted for the meteorological inputs and model parameters. The DLM-WQ estimated lake water level and water temperatures were in agreement to those of measured records with R2 equal to 0.96 and 0.99, respectively for the period 1994 to 2008. The estimated average evaporation from the lake, stream inflow, precipitation over the lake, groundwater fluxes, and outflow from the lake during 1994 to 2008 were found to be 32.0%, 25.0%, 19.0%, 0.3%, and 11.7%, respectively.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. Kathu Townlands: A High Density Earlier Stone Age Locality in the Interior of South Africa

    PubMed Central

    Walker, Steven J. H.; Lukich, Vasa; Chazan, Michael

    2014-01-01

    Kathu Townlands is a high density Earlier Stone Age locality in the Northern Cape Province, South Africa. Here we present the first detailed information on this locality based on analysis of a sample of lithic material from excavations by P. Beaumont and field observations made in the course of fieldwork in 2013. The results confirm the remarkably high artefact density at Kathu Townlands and do not provide evidence consistent with high energy transport as a mechanism of site formation, suggesting that Kathu Townlands was the site of intensive exploitation of highly siliceous outcroppings of banded iron formation. The results presented here provide a first step towards understanding this complex locality and point to the need for further research and the importance of preserving this locality in the face of intensive and rapid development. PMID:25058317

  20. 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.

  1. 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.

  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. Challenges and Recent Developments in Hearing Aids: Part I. Speech Understanding in Noise, Microphone Technologies and Noise Reduction Algorithms

    PubMed Central

    Chung, King

    2004-01-01

    This review discusses the challenges in hearing aid design and fitting and the recent developments in advanced signal processing technologies to meet these challenges. The first part of the review discusses the basic concepts and the building blocks of digital signal processing algorithms, namely, the signal detection and analysis unit, the decision rules, and the time constants involved in the execution of the decision. In addition, mechanisms and the differences in the implementation of various strategies used to reduce the negative effects of noise are discussed. These technologies include the microphone technologies that take advantage of the spatial differences between speech and noise and the noise reduction algorithms that take advantage of the spectral difference and temporal separation between speech and noise. The specific technologies discussed in this paper include first-order directional microphones, adaptive directional microphones, second-order directional microphones, microphone matching algorithms, array microphones, multichannel adaptive noise reduction algorithms, and synchrony detection noise reduction algorithms. Verification data for these technologies, if available, are also summarized. PMID:15678225

  4. 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.

  5. Adjusting for COPD severity in database research: developing and validating an algorithm

    PubMed Central

    Goossens, Lucas MA; Baker, Christine L; Monz, Brigitta U; Zou, Kelly H; Mölken, Maureen PMH Rutten-van

    2011-01-01

    Purpose When comparing chronic obstructive lung disease (COPD) interventions in database research, it is important to adjust for severity. Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines grade severity according to lung function. Most databases lack data on lung function. Previous database research has approximated COPD severity using demographics and healthcare utilization. This study aims to derive an algorithm for COPD severity using baseline data from a large respiratory trial (UPLIFT). Methods Partial proportional odds logit models were developed for probabilities of being in GOLD stages II, III and IV. Concordance between predicted and observed stage was assessed using kappa-statistics. Models were estimated in a random selection of 2/3 of patients and validated in the remainder. The analysis was repeated in a subsample with a balanced distribution across severity stages. Univariate associations of COPD severity with the covariates were tested as well. Results More severe COPD was associated with being male and younger, having quit smoking, lower BMI, osteoporosis, hospitalizations, using certain medications, and oxygen. After adjusting for these variables, co-morbidities, previous healthcare resource use (eg, emergency room, hospitalizations) and inhaled corticosteroids, xanthines, or mucolytics were no longer independently associated with COPD severity, although they were in univariate tests. The concordance was poor (kappa = 0.151) and only slightly better in the balanced sample (kappa = 0.215). Conclusion COPD severity cannot be reliably predicted from demographics and healthcare use. This limitation should be considered when interpreting findings from database studies, and additional research should explore other methods to account for COPD severity. PMID:22259243

  6. Using a multi-objective genetic algorithm for developing aerial sensor team search strategies

    NASA Astrophysics Data System (ADS)

    Ridder, Jeffrey P.; Herweg, Jared A.; Sciortino, John C., Jr.

    2008-04-01

    Finding certain associated signals in the modern electromagnetic environment can prove a difficult task due to signal characteristics and associated platform tactics as well as the systems used to find these signals. One approach to finding such signal sets is to employ multiple small unmanned aerial systems (UASs) equipped with RF sensors in a team to search an area. The search environment may be partially known, but with a significant level of uncertainty as to the locations and emissions behavior of the individual signals and their associated platforms. The team is likely to benefit from a combination of using uncertain a priori information for planning and online search algorithms for dynamic tasking of the team. Two search algorithms are examined for effectiveness: Archimedean spirals, in which the UASs comprising the team do not respond to the environment, and artificial potential fields, in which they use environmental perception and interactions to dynamically guide the search. A multi-objective genetic algorithm (MOGA) is used to explore the desirable characteristics of search algorithms for this problem using two performance objectives. The results indicate that the MOGA can successfully use uncertain a priori information to set the parameters of the search algorithms. Also, we find that artificial potential fields may result in good performance, but that each of the fields has a different contribution that may be appropriate only in certain states.

  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. 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.

  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. 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.

  12. 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

  13. 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

  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. Midlife adiposity predicts earlier onset of Alzheimer's dementia, neuropathology and presymptomatic cerebral amyloid accumulation.

    PubMed

    Chuang, Y-F; An, Y; Bilgel, M; Wong, D F; Troncoso, J C; O'Brien, R J; Breitner, J C; Ferruci, L; Resnick, S M; Thambisetty, M

    2016-07-01

    Understanding how midlife risk factors influence age at onset (AAO) of Alzheimer's disease (AD) may provide clues to delay disease expression. Although midlife adiposity predicts increased incidence of AD, it is unclear whether it affects AAO and severity of Alzheimer's neuropathology. Using a prospective population-based cohort, Baltimore Longitudinal Study of Aging (BLSA), this study aims to examine the relationships between midlife body mass index (BMI) and (1) AAO of AD (2) severity of Alzheimer's neuropathology and (3) fibrillar brain amyloid deposition during aging. We analyzed data on 1394 cognitively normal individuals at baseline (8643 visits; average follow-up interval 13.9 years), among whom 142 participants developed incident AD. In two subsamples of BLSA, 191 participants underwent autopsy and neuropathological assessment, and 75 non-demented individuals underwent brain amyloid imaging. Midlife adiposity was derived from BMI data at 50 years of age. We find that each unit increase in midlife BMI predicts earlier onset of AD by 6.7 months (P=0.013). Higher midlife BMI was associated with greater Braak neurofibrillary but not CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuritic plaque scores at autopsy overall. Associations between midlife BMI and brain amyloid burden approached statistical significance. Thus, higher midlife BMI was also associated with greater fibrillar amyloid measured by global mean cortical distribution volume ratio (P=0.075) and within the precuneus (left, P=0.061; right, P=0.079). In conclusion, midlife overweight predicts earlier onset of AD and greater burden of Alzheimer's neuropathology. A healthy BMI at midlife may delay the onset of AD.

  16. Identified research directions for using manufacturing knowledge earlier in the product lifecycle.

    PubMed

    Hedberg, Thomas D; Hartman, Nathan W; Rosche, Phil; Fischer, Kevin

    2017-01-01

    Design for Manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within Computer-Aided Design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customization on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities, or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is how can manufacturing knowledge, depending on its definition, be used earlier in the product lifecycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behavior, and context characteristics of product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product lifecycle.

  17. Vibrational self-consistent field calculations for spectroscopy of biological molecules: new algorithmic developments and applications.

    PubMed

    Roy, Tapta Kanchan; Gerber, R Benny

    2013-06-28

    This review describes the vibrational self-consistent field (VSCF) method and its other variants for computing anharmonic vibrational spectroscopy of biological molecules. The superiority and limitations of this algorithm are discussed with examples. The spectroscopic accuracy of the VSCF method is compared with experimental results and other available state-of-the-art algorithms for various biologically important systems. For large biological molecules with many vibrational modes, the scaling of computational effort is investigated. The accuracy of the vibrational spectra of biological molecules using the VSCF approach for different electronic structure methods is also assessed. Finally, a few open problems and challenges in this field are discussed.

  18. Development of homotopy algorithms for fixed-order mixed H2/H(infinity) controller synthesis

    NASA Technical Reports Server (NTRS)

    Whorton, M.; Buschek, H.; Calise, A. J.

    1994-01-01

    A major difficulty associated with H-infinity and mu-synthesis methods is the order of the resulting compensator. Whereas model and/or controller reduction techniques are sometimes applied, performance and robustness properties are not preserved. By directly constraining compensator order during the optimization process, these properties are better preserved, albeit at the expense of computational complexity. This paper presents a novel homotopy algorithm to synthesize fixed-order mixed H2/H-infinity compensators. Numerical results are presented for a four-disk flexible structure to evaluate the efficiency of the algorithm.

  19. A survey of DNA motif finding algorithms

    PubMed Central

    Das, Modan K; Dai, Ho-Kwok

    2007-01-01

    Background Unraveling the mechanisms that regulate gene expression is a major challenge in biology. An important task in this challenge is to identify regulatory elements, especially the binding sites in deoxyribonucleic acid (DNA) for transcription factors. These binding sites are short DNA segments that are called motifs. Recent advances in genome sequence availability and in high-throughput gene expression analysis technologies have allowed for the development of computational methods for motif finding. As a result, a large number of motif finding algorithms have been implemented and applied to various motif models over the past decade. This survey reviews the latest developments in DNA motif finding algorithms. Results Earlier algorithms use promoter sequences of coregulated genes from single genome and search for statistically overrepresented motifs. Recent algorithms are designed to use phylogenetic footprinting or orthologous sequences and also an integrated approach where promoter sequences of coregulated genes and phylogenetic footprinting are used. All the algorithms studied have been reported to correctly detect the motifs that have been previously detected by laboratory experimental approaches, and some algorithms were able to find novel motifs. However, most of these motif finding algorithms have been shown to work successfully in yeast and other lower organisms, but perform significantly worse in higher organisms. Conclusion Despite considerable efforts to date, DNA motif finding remains a complex challenge for biologists and computer scientists. Researchers have taken many different approaches in developing motif discovery tools and the progress made in this area of research is very encouraging. Performance comparison of different motif finding tools and identification of the best tools have proven to be a difficult task because tools are designed based on algorithms and motif models that are diverse and complex and our incomplete understanding of

  20. 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

  1. 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.

  2. Algorithms for Developing Test Questions from Sentences in Instructional Materials. Interim Report, January-September 1977.

    ERIC Educational Resources Information Center

    Roid, Gale; Finn, Patrick

    The feasibility of generating multiple-choice test questions by transforming sentences from prose instructional materials was examined. A computer-based algorithm was used to analyze prose subject matter and to identify high-information words. Sentences containing selected words were then transformed into multiple-choice items by four writers who…

  3. 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.

  4. TrackNTrace: A simple and extendable open-source framework for developing single-molecule localization and tracking algorithms.

    PubMed

    Stein, Simon Christoph; Thiart, Jan

    2016-11-25

    Super-resolution localization microscopy and single particle tracking are important tools for fluorescence microscopy. Both rely on detecting, and tracking, a large number of fluorescent markers using increasingly sophisticated computer algorithms. However, this rise in complexity makes it difficult to fine-tune parameters and detect inconsistencies, improve existing routines, or develop new approaches founded on established principles. We present an open-source MATLAB framework for single molecule localization, tracking and super-resolution applications. The purpose of this software is to facilitate the development, distribution, and comparison of methods in the community by providing a unique, easily extendable plugin-based system and combining it with a novel visualization system. This graphical interface incorporates possibilities for quick inspection of localization and tracking results, giving direct feedback of the quality achieved with the chosen algorithms and parameter values, as well as possible sources for errors. This is of great importance in practical applications and even more so when developing new techniques. The plugin system greatly simplifies the development of new methods as well as adapting and tailoring routines towards any research problem's individual requirements. We demonstrate its high speed and accuracy with plugins implementing state-of-the-art algorithms and show two biological applications.

  5. TrackNTrace: A simple and extendable open-source framework for developing single-molecule localization and tracking algorithms

    PubMed Central

    Stein, Simon Christoph; Thiart, Jan

    2016-01-01

    Super-resolution localization microscopy and single particle tracking are important tools for fluorescence microscopy. Both rely on detecting, and tracking, a large number of fluorescent markers using increasingly sophisticated computer algorithms. However, this rise in complexity makes it difficult to fine-tune parameters and detect inconsistencies, improve existing routines, or develop new approaches founded on established principles. We present an open-source MATLAB framework for single molecule localization, tracking and super-resolution applications. The purpose of this software is to facilitate the development, distribution, and comparison of methods in the community by providing a unique, easily extendable plugin-based system and combining it with a novel visualization system. This graphical interface incorporates possibilities for quick inspection of localization and tracking results, giving direct feedback of the quality achieved with the chosen algorithms and parameter values, as well as possible sources for errors. This is of great importance in practical applications and even more so when developing new techniques. The plugin system greatly simplifies the development of new methods as well as adapting and tailoring routines towards any research problem’s individual requirements. We demonstrate its high speed and accuracy with plugins implementing state-of-the-art algorithms and show two biological applications. PMID:27885259

  6. Development and Evaluation of Algorithms to Improve Small- and Medium-Size Commercial Building Operations

    SciTech Connect

    Kim, Woohyun; Katipamula, Srinivas; Lutes, Robert G.; Underhill, Ronald M.

    2016-10-31

    Small- and medium-sized (<100,000 sf) commercial buildings (SMBs) represent over 95% of the U.S. commercial building stock and consume over 60% of total site energy consumption. Many of these buildings use rudimentary controls that are mostly manual, with limited scheduling capability, no monitoring or failure management. Therefore, many of these buildings are operated inefficiently and consume excess energy. SMBs typically utilize packaged rooftop units (RTUs) that are controlled by an individual thermostat. There is increased urgency to improve the operating efficiency of existing commercial building stock in the U.S. for many reasons, chief among them is to mitigate the climate change impacts. Studies have shown that managing set points and schedules of the RTUs will result in up to 20% energy and cost savings. Another problem associated with RTUs is short-cycling, where an RTU goes through ON and OFF cycles too frequently. Excessive cycling can lead to excessive wear and lead to premature failure of the compressor or its components. The short cycling can result in a significantly decreased average efficiency (up to 10%), even if there are no physical failures in the equipment. Also, SMBs use a time-of-day scheduling is to start the RTUs before the building will be occupied and shut it off when unoccupied. Ensuring correct use of the zone set points and eliminating frequent cycling of RTUs thereby leading to persistent building operations can significantly increase the operational efficiency of the SMBs. A growing trend is to use low-cost control infrastructure that can enable scalable and cost-effective intelligent building operations. The work reported in this report describes three algorithms for detecting the zone set point temperature, RTU cycling rate and occupancy schedule detection that can be deployed on the low-cost infrastructure. These algorithms only require the zone temperature data for detection. The algorithms have been tested and validated using

  7. Development of a Satellite-based evapotranspiration algorithm: A case study for Two Deciduous Forest Sites

    NASA Astrophysics Data System (ADS)

    Elmasri, B.; Rahman, A. F.

    2011-12-01

    We introduce a new methodology to estimate 8-day average daily evapotranspiration (ET) using both routinely available data and the Penman-Monteith (P-M) equation. Our algorithm considers the environmental constraints on surface resistance and ET by (1) including vapor pressure deficit (VPD), incoming solar radiation, soil moisture, and temperature constraints on stomatal conductance; (2) using leaf area index (LAI) to scale from the leaf to the canopy conductance; and (3) calculating canopy resistance as a function of environmental variables such as net radiation, precipitation index, and VPD. Remote sensing data from the Moderate Resolution Spectroradiometer (MODIS) and the Advance Microwave Scanning Radiometer-EOS (AMSR-E) were used to estimate ET by using MODIS land surface temperature (LST) to estimated VPD, AMSR-E soil moisture to estimate canopy conductance, and MODIS surface emissivity and albedo to estimate shortwave and net radiation. The algorithm was evaluated using ET observations from two AmeriFlux Eddy covariance flux towers located at the Morgan Monroe State Forest (MMSF) in Indiana and the Harvard Forest (HarvF) in Massachusetts for the periods of 2003-2008. ET estimates from our algorithm was compared to the flux observations. Results indicated a root mean square error (RMSE) of the 8-day average ET of 0.57 mm for the HarvF and 0.47 mm for the MMSF. A significant correlation was found between the estimated 8-day average ET and the observed 8-day average ET with r2 of 0.84 for the HarvF and 0.88 for the MMSF. Using tower meteorological data, the r2 slightly increased to 0.90 for the MMSF. The algorithms for VPD and radiation were tested against flux observations and found a strong correlation with r2 ranging from 0.68 to 0.82. Sensitivity analysis revealed that the modeled ET predictions are highly sensitive to changes in the canopy resistance values, so accurate estimates of canopy resistance is essential for improve ET predictions. Our algorithm

  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. 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.

  11. 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).

  12. Testing and Development of the Onsite Earthquake Early Warning Algorithm to Reduce Event Uncertainties

    NASA Astrophysics Data System (ADS)

    Andrews, J. R.; Cochran, E. S.; Hauksson, E.; Felizardo, C.; Liu, T.; Ross, Z.; Heaton, T. H.

    2015-12-01

    Primary metrics for measuring earthquake early warning (EEW) system and algorithm performance are the rate of false alarms and the uncertainty in earthquake parameters. The Onsite algorithm, currently one of three EEW algorithms implemented in ShakeAlert, uses the ground-motion period parameter (τc) and peak initial displacement parameter (Pd) to estimate the magnitude and expected ground shaking of an ongoing earthquake. It is the only algorithm originally designed to issue single station alerts, necessitating that results from individual stations be as reliable and accurate as possible.The ShakeAlert system has been undergoing testing on continuous real-time data in California for several years, and the latest version of the Onsite algorithm for several months. This permits analysis of the response to a range of signals, from environmental noise to hardware testing and maintenance procedures to moderate or large earthquake signals at varying distances from the networks. We find that our existing discriminator, relying only on τc and Pd, while performing well to exclude large teleseismic events, is less effective for moderate regional events and can also incorrectly exclude data from local events. Motivated by these experiences, we use a collection of waveforms from potentially problematic 'noise' events and real earthquakes to explore methods to discriminate real and false events, using the ground motion and period parameters available in Onsite's processing methodology. Once an event is correctly identified, a magnitude and location estimate is critical to determining the expected ground shaking. Scatter in the measured parameters translates to higher than desired uncertainty in Onsite's current calculations We present an overview of alternative methods, including incorporation of polarization information, to improve parameter determination for a test suite including both large (M4 to M7) events and three years of small to moderate events across California.

  13. 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%.

  14. A new augmentation based algorithm for extracting maximal chordal subgraphs

    SciTech Connect

    Bhowmick, Sanjukta; Chen, Tzu-Yi; Halappanavar, Mahantesh

    2014-10-18

    If every cycle of a graph is chordal length greater than three then it contains an edge between non-adjacent vertices. Chordal graphs are of interest both theoretically, since they admit polynomial time solutions to a range of NP-hard graph problems, and practically, since they arise in many applications including sparse linear algebra, computer vision, and computational biology. A maximal chordal subgraph is a chordal subgraph that is not a proper subgraph of any other chordal subgraph. Existing algorithms for computing maximal chordal subgraphs depend on dynamically ordering the vertices, which is an inherently sequential process and therefore limits the algorithms’ parallelizability. In our paper we explore techniques to develop a scalable parallel algorithm for extracting a maximal chordal subgraph. We demonstrate that an earlier attempt at developing a parallel algorithm may induce a non-optimal vertex ordering and is therefore not guaranteed to terminate with a maximal chordal subgraph. We then give a new algorithm that first computes and then repeatedly augments a spanning chordal subgraph. After proving that the algorithm terminates with a maximal chordal subgraph, we then demonstrate that this algorithm is more amenable to parallelization and that the parallel version also terminates with a maximal chordal subgraph. That said, the complexity of the new algorithm is higher than that of the previous parallel algorithm, although the earlier algorithm computes a chordal subgraph which is not guaranteed to be maximal. Finally, we experimented with our augmentation-based algorithm on both synthetic and real-world graphs. We provide scalability results and also explore the effect of different choices for the initial spanning chordal subgraph on both the running time and on the number of edges in the maximal chordal subgraph.

  15. A new augmentation based algorithm for extracting maximal chordal subgraphs

    DOE PAGES

    Bhowmick, Sanjukta; Chen, Tzu-Yi; Halappanavar, Mahantesh

    2014-10-18

    If every cycle of a graph is chordal length greater than three then it contains an edge between non-adjacent vertices. Chordal graphs are of interest both theoretically, since they admit polynomial time solutions to a range of NP-hard graph problems, and practically, since they arise in many applications including sparse linear algebra, computer vision, and computational biology. A maximal chordal subgraph is a chordal subgraph that is not a proper subgraph of any other chordal subgraph. Existing algorithms for computing maximal chordal subgraphs depend on dynamically ordering the vertices, which is an inherently sequential process and therefore limits the algorithms’more » parallelizability. In our paper we explore techniques to develop a scalable parallel algorithm for extracting a maximal chordal subgraph. We demonstrate that an earlier attempt at developing a parallel algorithm may induce a non-optimal vertex ordering and is therefore not guaranteed to terminate with a maximal chordal subgraph. We then give a new algorithm that first computes and then repeatedly augments a spanning chordal subgraph. After proving that the algorithm terminates with a maximal chordal subgraph, we then demonstrate that this algorithm is more amenable to parallelization and that the parallel version also terminates with a maximal chordal subgraph. That said, the complexity of the new algorithm is higher than that of the previous parallel algorithm, although the earlier algorithm computes a chordal subgraph which is not guaranteed to be maximal. Finally, we experimented with our augmentation-based algorithm on both synthetic and real-world graphs. We provide scalability results and also explore the effect of different choices for the initial spanning chordal subgraph on both the running time and on the number of edges in the maximal chordal subgraph.« less

  16. 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

  17. Development of a voltage-dependent current noise algorithm for conductance-based stochastic modelling of auditory nerve fibres.

    PubMed

    Badenhorst, Werner; Hanekom, Tania; Hanekom, Johan J

    2016-12-01

    This study presents the development of an alternative noise current term and novel voltage-dependent current noise algorithm for conductance-based stochastic auditory nerve fibre (ANF) models. ANFs are known to have significant variance in threshold stimulus which affects temporal characteristics such as latency. This variance is primarily caused by the stochastic behaviour or microscopic fluctuations of the node of Ranvier's voltage-dependent sodium channels of which the intensity is a function of membrane voltage. Though easy to implement and low in computational cost, existing current noise models have two deficiencies: it is independent of membrane voltage, and it is unable to inherently determine the noise intensity required to produce in vivo measured discharge probability functions. The proposed algorithm overcomes these deficiencies while maintaining its low computational cost and ease of implementation compared to other conductance and Markovian-based stochastic models. The algorithm is applied to a Hodgkin-Huxley-based compartmental cat ANF model and validated via comparison of the threshold probability and latency distributions to measured cat ANF data. Simulation results show the algorithm's adherence to in vivo stochastic fibre characteristics such as an exponential relationship between the membrane noise and transmembrane voltage, a negative linear relationship between the log of the relative spread of the discharge probability and the log of the fibre diameter and a decrease in latency with an increase in stimulus intensity.

  18. 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.

  19. 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.

  20. Generalizability of hybrid search algorithms to map multiple biomedical vocabulary domains.

    PubMed

    Nachimuthu, Senthil K; Woolstenhulme, R Dean

    2006-01-01

    Hybrid text matching algorithms similar to those used for DNA sequencing were developed by 3M Health Information Systems to map a noisy legacy codeset to the 3M Healthcare Data Dictionary (3M HDD). Applying these techniques to map other biomedical vocabularies was briefly introduced in an earlier paper describing the algorithms. We now present results from successfully utilizing them to map different vocabularies across multiple biomedical domains, proving their generalizability.

  1. Development and Evaluation of the GCOM-W1 AMSR2 Snow Depth and Snow Water Equivalent Algorithm

    NASA Astrophysics Data System (ADS)

    Kelly, R. E. J.; Saberi, N.; Li, Q.

    2015-12-01

    An evaluation is presented of snow depth (SD) and snow water equivalent (SWE) estimates from recent developments to the standard snow product algorithm for the Advanced Microwave Scanning Radiometer - 2 (AMSR2) aboard the Global Change Observation Mission - Water. AMSR2 is designed as a follow-on from the successful Advanced Microwave Scanning Radiometer - EOS that ceased formal operations in 2011. The standard SD product for AMSR2 has been updated in two ways. First, the detection algorithm identifies various observable geophysical targets that can confound SD / SWE estimation (water bodies [including freeze/thaw state], rainfall, high altitude plateau regions [e.g. Tibetan plateau]) before detecting moderate and shallow snow. Second, the implementation of the Dense Media Radiative Transfer model (DMRT) originally developed by Tsang et al. (2000) and more recently adapted by Picard et al. (2011) is used to estimate SWE and SD. The implementation combines snow grain size and density parameterizations originally developed by Kelly et al. (2003). Snow grain size is estimated from the tracking of estimated air temperatures that are used to drive an empirical grain growth model. Snow density is estimated from the Sturm et al. (2010) scheme. Efforts have been made to keep the approach tractable while reducing uncertainty in these input variables. Results are presented from the recent winter seasons since 2012 to illustrate the performance of the new approach in comparison with the initial AMSR2 algorithm.

  2. 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.

  3. Atmospheric Correction, Vicarious Calibration and Development of Algorithms for Quantifying Cyanobacteria Blooms from Oceansat-1 OCM Satellite Data

    NASA Astrophysics Data System (ADS)

    Dash, P.; Walker, N. D.; Mishra, D. R.; Hu, C.; D'Sa, E. J.; Pinckney, J. L.

    2011-12-01

    Cyanobacteria represent a major harmful algal group in fresh to brackish water environments. Lac des Allemands, a freshwater lake located southwest of New Orleans, Louisiana on the upper end of the Barataria Estuary, provides a natural laboratory for remote characterization of cyanobacteria blooms because of their seasonal occurrence. The Ocean Colour Monitor (OCM) sensor provides radiance measurements similar to SeaWiFS but with higher spatial resolution. However, OCM does not have a standard atmospheric correction procedure, and it is difficult to find a detailed description of the entire atmospheric correction procedure for ocean (or lake) in one place. Atmospheric correction of satellite data over small lakes and estuaries (Case 2 waters) is also challenging due to difficulties in estimation of aerosol scattering accurately in these areas. Therefore, an atmospheric correction procedure was written for processing OCM data, based on the extensive work done for SeaWiFS. Since OCM-retrieved radiances were abnormally low in the blue wavelength region, a vicarious calibration procedure was also developed. Empirical inversion algorithms were developed to convert the OCM remote sensing reflectance (Rrs) at bands centered at 510.6 and 556.4 nm to concentrations of phycocyanin (PC), the primary cyanobacterial pigment. A holistic approach was followed to minimize the influence of other optically active constituents on the PC algorithm. Similarly, empirical algorithms to estimate chlorophyll a (Chl a) concentrations were developed using OCM bands centered at 556.4 and 669 nm. The best PC algorithm (R2=0.7450, p<0.0001, n=72) yielded a root mean square error (RMSE) of 36.92 μg/L with a relative RMSE of 10.27% (PC from 2.75-363.50 μg/L, n=48). The best algorithm for Chl a (R2=0.7510, p<0.0001, n=72) produced an RMSE of 31.19 μg/L with a relative RMSE of 16.56% (Chl a from 9.46-212.76 μg/L, n=48). While more field data are required to further validate the long

  4. 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.

  5. Transform methods for developing parallel algorithms for cyclic-block signal processing

    NASA Astrophysics Data System (ADS)

    Marshall, T. G., Jr.

    A class of FIR and IIR single and multirate parallel filtering algorithms is introduced in which blocks of inputs and outputs are processed on-the-fly in a cyclic manner. There is no inherent latency introduced by the decomposition procedure giving the parallelism, the system latency being primarily due to the component processors. The structure is particularly well-suited for systems in which the component processors are the familiar DSP chips optimized for convolution although other component structures can be accommodated. In particular, the automatic data shifting feature of the TMS320 series processors can be utilized in these algorithms. A transform notation, introduced for digital filter banks, is recast in the desired form for this application. The resulting structure of the system, in this notation, is a circulant matrix for FIR filtering or a related matrix in other cases. The cyclic properties of the system and useful implementation flexibility result from this matrix structure.

  6. On the development and application of a continuous-discrete recursive prediction error algorithm.

    PubMed

    Stigter, J D; Beck, M B

    2004-10-01

    Recursive state and parameter reconstruction is a well-established field in control theory. In the current paper we derive a continuous-discrete version of recursive prediction error algorithm and apply the filter in an environmental and biological setting as a possible alternative to the well-known extended Kalman filter. The framework from which the derivation is started is the so-called 'innovations-format' of the (continuous time) system model, including (discrete time) measurements. After the algorithm has been motivated and derived, it is subsequently applied to hypothetical and 'real-life' case studies including reconstruction of biokinetic parameters and parameters characterizing the dynamics of a river in the United Kingdom. Advantages and characteristics of the method are discussed.

  7. Predicting pregnancy rate following multiple embryo transfers using algorithms developed through static image analysis.

    PubMed

    Tian, Yun; Wang, Wei; Yin, Yabo; Wang, Weizhou; Duan, Fuqing; Zhao, Shifeng

    2017-02-16

    Single-embryo image assessment involves a high degree of inaccuracy because of the imprecise labelling of the transferred embryo images. In this study, we considered the entire transfer cycle to predict the implantation potential of embryos, and propose a novel algorithm based on a combination of local binary pattern texture feature and Adaboost classifiers to predict pregnancy rate. The first step of the proposed method was to extract the features of the embryo images using the local binary pattern operator. After this, multiple embryo images in a transfer cycle were considered as one entity, and the pregnancy rate was predicted using three classifiers: the Real Adaboost, Gentle Adaboost, and Modest Adaboost. Finally, the pregnancy rate was determined via the majority vote rule based on classification results of the three Adaboost classifiers. The proposed algorithm was verified to have a good predictive performance and may assist the embryologist and clinician to select embryos to transfer and in turn improve pregnancy rate.

  8. 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.

  9. Smart respiratory monitoring: clinical development and validation of the IPI™ (Integrated Pulmonary Index) algorithm.

    PubMed

    Ronen, M; Weissbrod, R; Overdyk, F J; Ajizian, S

    2017-04-01

    Continuous electronic monitoring of patient respiratory status frequently includes PetCO2 (end tidal CO2), RR (respiration rate), SpO2 (arterial oxygen saturation), and PR (pulse rate). Interpreting and integrating these vital signs as numbers or waveforms is routinely done by anesthesiologists and intensivists but is challenging for clinicians in low acuity areas such as medical wards, where continuous electronic respiratory monitoring is becoming more common place. We describe a heuristic algorithm that simplifies the interpretation of these four parameters in assessing a patient's respiratory status, the Integrated Pulmonary Index (IPI). The IPI algorithm is a mathematical model combining SpO2, RR, PR, and PetCO2 into a single value between 1 and 10 that summarizes the adequacy of ventilation and oxygenation at that point in time. The algorithm was designed using a fuzzy logic inference model to incorporate expert clinical opinions. The algorithm was verified by comparison to experts' scoring of clinical scenarios. The validity of the index was tested in a retrospective analysis of continuous SpO2, RR, PR, and PetCO2 readings obtained from 523 patients in a variety of clinical settings. IPI correlated well with expert interpretation of the continuous respiratory data (R = 0.83, p < 0.001), with agreement of -0.5 ± 1.4. Receiver operating curves analysis resulted in high levels of sensitivity (ranging from 0.83 to 1.00), and corresponding specificity (ranging from 0.96 to 0.74), based on IPI thresholds 3-6. The IPI reliably interpreted the respiratory status of patients in multiple areas of care using off-line continuous respiratory data. Further prospective studies are required to evaluate IPI in real time in clinical settings.

  10. Intermediate Level Computer Vision Processing Algorithm Development for the Content Addressable Array Parallel Processor.

    DTIC Science & Technology

    1986-11-29

    Madison, Wiscon- sin, August 1982. [161 Fitzpatrick, D. T., Foderaro, J. K., Katevenis, M . G. H., Landman, H. A.. Patterson, D. A., Peek, J. B ., Peshkess...October 18-22, 1982. [33] Levitan , S. P., Parallel Algorithms and Architectures: A Programmer’s Per- 35 AN I%. . m ,,-1we, V .r V . , - .7...e. . . e. ** -! ~ * ~ - . . . . . 0.Wty C^11Cri m . op~ bo* pa, U FILE- copy(4 REPORT DOCUMENTATION PAGE e PQTSIC%.RSTV C6AUSIPCATION 16

  11. 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.

  12. Development and evaluation of a data-adaptive alerting algorithm for univariate temporal biosurveillance data.

    PubMed

    Elbert, Yevgeniy; Burkom, Howard S

    2009-11-20

    This paper discusses further advances in making robust predictions with the Holt-Winters forecasts for a variety of syndromic time series behaviors and introduces a control-chart detection approach based on these forecasts. Using three collections of time series data, we compare biosurveillance alerting methods with quantified measures of forecast agreement, signal sensitivity, and time-to-detect. The study presents practical rules for initialization and parameterization of biosurveillance time series. Several outbreak scenarios are used for detection comparison. We derive an alerting algorithm from forecasts using Holt-Winters-generalized smoothing for prospective application to daily syndromic time series. The derived algorithm is compared with simple control-chart adaptations and to more computationally intensive regression modeling methods. The comparisons are conducted on background data from both authentic and simulated data streams. Both types of background data include time series that vary widely by both mean value and cyclic or seasonal behavior. Plausible, simulated signals are added to the background data for detection performance testing at signal strengths calculated to be neither too easy nor too hard to separate the compared methods. Results show that both the sensitivity and the timeliness of the Holt-Winters-based algorithm proved to be comparable or superior to that of the more traditional prediction methods used for syndromic surveillance.

  13. 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

  14. 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

  15. Development and evaluation of a modis vegetation index compositing algorithm for long-term climate studies

    NASA Astrophysics Data System (ADS)

    Solano Barajas, Ramon

    The acquisition of remote sensing data having an investigated quality level constitutes an important step to advance our understanding of the vegetation response to environmental factors. Spaceborne sensors introduce additional challenges that should be addressed to assure that derived findings are based on real phenomena, and not biased or misguided by instrument features or processing artifacts. As a consequence, updates to incorporate new advances and user requirements are regularly found on most cutting edge systems such as the Moderate Resolution Imaging Spectroradiometer (MODIS) system. In this dissertation, the objective was to design, characterize and assess any possible departure from current values, a MODIS vegetation index (VI) algorithm for restoring the continuity 16-day 1-km product, based on the new 8-day 500-m MODIS surface reflectance (SR) product scheduled for the forthcoming MODIS Collection 6 (C6). Additionally, the impact of increasing the time resolution (by reducing the compositing period) from 16 to 8 days for the future basic MODIS C6 VI product was also assessed. The performance of the proposed algorithm was evaluated using high quality reference data and known biophysical relationships at several spatial and temporal scales. Firstly, it was evaluated using data from the AERONET-based Surface Reflectance Validation Network (ASRVN), FLUXNET-derived ecosystem gross primary productivity (GPP) and an analysis of the seasonality parameters derived from current Collection 5 (C5) and proxy C6 VI collections. The performance of the 8-day VI version was evaluated and contrasted with current 16-day using the reported correlation of the Enhanced Vegetation Index (EVI) with the GPP derived from CO2 flux measurements. Secondly, we performed an analysis at spatial level using entire images (or "tiles") to assess the Bidirectional Reflectance Distribution Function (BRDF) effects on the VI product, as these can cause biases on the SR and VIs from scanning

  16. 3/4 view of newer station's south and east elevations. Earlier ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3/4 view of newer station's south and east elevations. Earlier photos taken from the tower atop this structure. - Vermilion Life Saving Station, Shore of Lake Superior, 10 miles west of Whitefish Point, Paradise, Chippewa County, MI

  17. 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

  18. Drowsiness/alertness algorithm development and validation using synchronized EEG and cognitive performance to individualize a generalized model.

    PubMed

    Johnson, Robin R; Popovic, Djordje P; Olmstead, Richard E; Stikic, Maja; Levendowski, Daniel J; Berka, Chris

    2011-05-01

    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) lack of 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.

  19. 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

  20. 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

  1. Some computational challenges of developing efficient parallel algorithms for data-dependent computations in thermal-hydraulics supercomputer applications

    SciTech Connect

    Woodruff, S.B.

    1992-01-01

    The Transient Reactor Analysis Code (TRAC), which features a two- fluid treatment of thermal-hydraulics, is designed to model transients in water reactors and related facilities. One of the major computational costs associated with TRAC and similar codes is calculating constitutive coefficients. Although the formulations for these coefficients are local the costs are flow-regime- or data-dependent; i.e., the computations needed for a given spatial node often vary widely as a function of time. Consequently, poor load balancing will degrade efficiency on either vector or data parallel architectures when the data are organized according to spatial location. Unfortunately, a general automatic solution to the load-balancing problem associated with data-dependent computations is not yet available for massively parallel architectures. This document discusses why developers algorithms, such as a neural net representation, that do not exhibit algorithms, such as a neural net representation, that do not exhibit load-balancing problems.

  2. 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.

  3. 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

  4. Early Closure of Gastroschisis After Silo Placement Correlates with Earlier Enteral Feeding

    PubMed Central

    Harris, Jamie; Poirier, Jennifer; Selip, Debra; Pillai, Srikumar; N. Shah, Ami; Jackson, Carl-Christian; Chiu, Bill

    2015-01-01

    Objectives: Gastroschisis is a congenital anomaly affecting 2.3-4.4/10,000 births. Previous studies show initiation of early enteral feeds predicts improved outcomes. We hypothesize that earlier definitive closure after silo placement; can lead to earlier enteral feed initiation. Design/ Setting/ Duration: Retrospective review of patients with gastroschisis from 2005 and 2014 at a single institution. Material and Methods: The data, including ethnicity, gestational age, birth weight, time to definitive closure, and time of first and full feeds, were analyzed using both Spearman’s rho and the Kruskal-Wallis rank sum test where appropriate; a p value less than 0.05 was considered significant. Results: Forty-three patients (24 males, 19 females) born with gastroschisis were identified. Overall survival rate was 88% (38/43). Forty of the 43 patients had a silo placed prior to definitive closure. Median days to closure were 6 (0 to 85) days. First feeds on average began on day of life (DOL) 17, and full feeds on DOL 25. Earlier closure of gastroschisis correlated with early initiation of feeds (p=0.0001) and shorter time to full feeds (p=0.018), closure by DOL4 showed a trend toward earlier feeding (p=0.13). Conclusion: Earlier closure of gastroschisis after silo placement was associated with earlier feed initiation and shorter time to full feeds. PMID:26290810

  5. 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.

  6. A multi-channel feedback algorithm for the development of active liners to reduce noise in flow duct applications

    NASA Astrophysics Data System (ADS)

    Mazeaud, B.; Galland, M.-A.

    2007-10-01

    The present paper deals with the design and development of the active part of a hybrid acoustic treatment combining porous material properties and active control techniques. Such an acoustic system was developed to reduce evolutionary tones in flow duct applications. Attention was particularly focused on the optimization process of the controller part of the hybrid cell. A piezo-electric transducer combining efficiency and compactness was selected as a secondary source. A digital adaptive feedback control algorithm was specially developed in order to operate independently cell by cell, and to facilitate a subsequent increase in the liner surface. An adaptive bandpass filter was used to prevent the development of instabilities due to the coupling occurring between cells. Special care was taken in the development of such systems for time-varying primary signals. An automatic frequency detection loop was therefore introduced in the control algorithm, enabling the continuous adaptation of the bandpass filtering. The multi-cell structure was experimentally validated for a four-cell system located on a duct wall in the presence of flow. Substantial noise reduction was obtained throughout the 0.7-2.5 kHz frequency range, with flow velocities up to 50 m/s.

  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. 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.

  9. Research on Quantum Algorithms at the Institute for Quantum Information

    DTIC Science & Technology

    2009-10-17

    developed earlier by Aliferis, Gottesman, and Preskill to encompass leakage-reduction units, such as those based on quantum teleportation . They also...NUMBER QA - Research on Quantum Algorithms at the Institute for W91INF-05-I-0294 Quantum lnfonnation 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...ABSTRACT The central goals ofour project are (I) to bring large-scale quantum computers closer to realization by proposing and analyzing new schemes for

  10. Development of a deterministic downscaling algorithm for remote sensing soil moisture footprint using soil and vegetation classifications

    NASA Astrophysics Data System (ADS)

    Shin, Yongchul; Mohanty, Binayak P.

    2013-10-01

    Soil moisture (SM) at the local scale is required to account for small-scale spatial heterogeneity of land surface because many hydrological processes manifest at scales ranging from cm to km. Although remote sensing (RS) platforms provide large-scale soil moisture dynamics, scale discrepancy between observation scale (e.g., approximately several kilometers) and modeling scale (e.g., few hundred meters) leads to uncertainties in the performance of land surface hydrologic models. To overcome this drawback, we developed a new deterministic downscaling algorithm (DDA) for estimating fine-scale soil moisture with pixel-based RS soil moisture and evapotranspiration (ET) products using a genetic algorithm. This approach was evaluated under various synthetic and field experiments (Little Washita-LW 13 and 21, Oklahoma) conditions including homogeneous and heterogeneous land surface conditions composed of different soil textures and vegetations. Our algorithm is based on determining effective soil hydraulic properties for different subpixels within a RS pixel and estimating the long-term soil moisture dynamics of individual subpixels using the hydrological model with the extracted soil hydraulic parameters. The soil moisture dynamics of subpixels from synthetic experiments matched well with the observations under heterogeneous land surface condition, although uncertainties (Mean Bias Error, MBE: -0.073 to -0.049) exist. Field experiments have typically more variations due to weather conditions, measurement errors, unknown bottom boundary conditions, and scale discrepancy between remote sensing pixel and model grid resolution. However, the soil moisture estimates of individual subpixels (from the airborne Electronically Scanned Thinned Array Radiometer (ESTAR) footprints of 800 m × 800 m) downscaled by this approach matched well (R: 0.724 to -0.914, MBE: -0.203 to -0.169 for the LW 13; R: 0.343-0.865, MBE: -0.165 to -0.122 for the LW 21) with the in situ local scale soil

  11. Algorithm development for SDI weapons system allocation. Final report, December 1987-May 1989

    SciTech Connect

    Blankenship, G.L.; Bennett, W.

    1989-06-01

    While several SDI weapons systems can provide adequate defense in a one-on-one basis, a coordinated attack by several enemy missiles launched over a substantial volume will be difficult to resist without an efficient command and control system for warfare coordination. This study of weapons allocation - coordination algorithms, is based on dynamical models for the missile/decoy systems including noise effects and uncertainties in the model parameters. Performance of the weapons targeting system may be measured in terms of the expected number of targets eliminated in a given interval (phase of operations) or the expected time to eliminate all the targets in a given region. Scheduling weapons deployment is a problem of constrained optimal (weapons) and state variables. The selection of weapons deployment tactics is based on solution of a complex optimization problem. We have conducted an investigation of advanced modeling, stochastic control, and scheduling methodologies for aspects of the SDI weapons allocation problem - several platforms with assets of different character defending against a diverse collection of targets. The models for such scenarios lead to stochastic scheduling problems that can not be handled by conventional analytical methods. The authors describe several different analytical approaches that have the potential for synthesis of effective engagement algorithms.

  12. Improvement and further development of SSM/I overland parameter algorithms using the WetNet workstation

    NASA Technical Reports Server (NTRS)

    Neale, Christopher M. U.; Mcdonnell, Jeffrey J.; Ramsey, Douglas; Hipps, Lawrence; Tarboton, David

    1993-01-01

    Since the launch of the DMSP Special Sensor Microwave/Imager (SSM/I), several algorithms have been developed to retrieve overland parameters. These include the present operational algorithms resulting from the Navy calibration/validation effort such as land surface type (Neale et al. 1990), land surface temperature (McFarland et al. 1990), surface moisture (McFarland and Neale, 1991) and snow parameters (McFarland and Neale, 1991). In addition, other work has been done including the classification of snow cover and precipitation using the SSM/I (Grody, 1991). Due to the empirical nature of most of the above mentioned algorithms, further research is warranted and improvements can probably be obtained through a combination of radiative transfer modelling to study the physical processes governing the microwave emissions at the SSM/I frequencies, and the incorporation of additional ground truth data and special cases into the regression data sets. We have proposed specifically to improve the retrieval of surface moisture and snow parameters using the WetNet SSM/I data sets along with ground truth information namely climatic variables from the NOAA cooperative network of weather stations as well as imagery from other satellite sensors such as the AVHRR and Thematic Mapper. In the case of surface moisture retrievals the characterization of vegetation density is of primary concern. The higher spatial resolution satellite imagery collected at concurrent periods will be used to characterize vegetation types and amounts which, along with radiative transfer modelling should lead to more physically based retrievals. Snow parameter retrieval algorithm improvement will initially concentrate on the classification of snowpacks (dry snow, wet snow, refrozen snow) and later on specific products such as snow water equivalent. Significant accomplishments in the past year are presented.

  13. User's Manual for the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA)

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.; Cheatwood, F. McNeil

    1996-01-01

    This user's manual provides detailed instructions for the installation and the application of version 4.1 of the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA). Also provides simulation of flow field in thermochemical nonequilibrium around vehicles traveling at hypersonic velocities through the atmosphere. Earlier versions of LAURA were predominantly research codes, and they had minimal (or no) documentation. This manual describes UNIX-based utilities for customizing the code for special applications that also minimize system resource requirements. The algorithm is reviewed, and the various program options are related to specific equations and variables in the theoretical development.

  14. SU-E-T-252: Developing a Pencil Beam Dose Calculation Algorithm for CyberKnife System

    SciTech Connect

    Liang, B; Liu, B; Zhou, F; Xu, S; Wu, Q

    2015-06-15

    Purpose: Currently there are two dose calculation algorithms available in the Cyberknife planning system: ray-tracing and Monte Carlo, which is either not accurate or time-consuming for irregular field shaped by the MLC that was recently introduced. The purpose of this study is to develop a fast and accurate pencil beam dose calculation algorithm which can handle irregular field. Methods: A pencil beam dose calculation algorithm widely used in Linac system is modified. The algorithm models both primary (short range) and scatter (long range) components with a single input parameter: TPR{sub 20}/{sub 10}. The TPR{sub 20}/{sub 20}/{sub 10} value was first estimated to derive an initial set of pencil beam model parameters (PBMP). The agreement between predicted and measured TPRs for all cones were evaluated using the root mean square of the difference (RMSTPR), which was then minimized by adjusting PBMPs. PBMPs are further tuned to minimize OCR RMS (RMSocr) by focusing at the outfield region. Finally, an arbitrary intensity profile is optimized by minimizing RMSocr difference at infield region. To test model validity, the PBMPs were obtained by fitting to only a subset of cones (4) and applied to all cones (12) for evaluation. Results: With RMS values normalized to the dmax and all cones combined, the average RMSTPR at build-up and descending region is 2.3% and 0.4%, respectively. The RMSocr at infield, penumbra and outfield region is 1.5%, 7.8% and 0.6%, respectively. Average DTA in penumbra region is 0.5mm. There is no trend found in TPR or OCR agreement among cones or depths. Conclusion: We have developed a pencil beam algorithm for Cyberknife system. The prediction agrees well with commissioning data. Only a subset of measurements is needed to derive the model. Further improvements are needed for TPR buildup region and OCR penumbra. Experimental validations on MLC shaped irregular field needs to be performed. This work was partially supported by the National

  15. 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

  16. 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

  17. 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…

  18. Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes

    PubMed Central

    Steltzer, Heidi; Landry, Chris; Painter, Thomas H.; Anderson, Justin; Ayres, Edward

    2009-01-01

    Dust deposition to mountain snow cover, which has increased since the late 19th century, accelerates the rate of snowmelt by increasing the solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but is decoupled from seasonal warming. Climate warming advances the timing of snowmelt and early season phenological events (e.g., the onset of greening and flowering); however, earlier snowmelt without warmer temperatures may have a different effect on phenology. Here, we report the results of a set of snowmelt manipulations in which radiation-absorbing fabric and the addition and removal of dust from the surface of the snowpack advanced or delayed snowmelt in the alpine tundra. These changes in the timing of snowmelt were superimposed on a system where the timing of snowmelt varies with topography and has been affected by increased dust loading. At the community level, phenology exhibited a threshold response to the timing of snowmelt. Greening and flowering were delayed before seasonal warming, after which there was a linear relationship between the date of snowmelt and the timing of phenological events. Consequently, the effects of earlier snowmelt on phenology differed in relation to topography, which resulted in increasing synchronicity in phenology across the alpine landscape with increasingly earlier snowmelt. The consequences of earlier snowmelt from increased dust deposition differ from climate warming and include delayed phenology, leading to synchronized growth and flowering across the landscape and the opportunity for altered species interactions, landscape-scale gene flow via pollination, and nutrient cycling. PMID:19564599

  19. Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes.

    PubMed

    Steltzer, Heidi; Landry, Chris; Painter, Thomas H; Anderson, Justin; Ayres, Edward

    2009-07-14

    Dust deposition to mountain snow cover, which has increased since the late 19(th) century, accelerates the rate of snowmelt by increasing the solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but is decoupled from seasonal warming. Climate warming advances the timing of snowmelt and early season phenological events (e.g., the onset of greening and flowering); however, earlier snowmelt without warmer temperatures may have a different effect on phenology. Here, we report the results of a set of snowmelt manipulations in which radiation-absorbing fabric and the addition and removal of dust from the surface of the snowpack advanced or delayed snowmelt in the alpine tundra. These changes in the timing of snowmelt were superimposed on a system where the timing of snowmelt varies with topography and has been affected by increased dust loading. At the community level, phenology exhibited a threshold response to the timing of snowmelt. Greening and flowering were delayed before seasonal warming, after which there was a linear relationship between the date of snowmelt and the timing of phenological events. Consequently, the effects of earlier snowmelt on phenology differed in relation to topography, which resulted in increasing synchronicity in phenology across the alpine landscape with increasingly earlier snowmelt. The consequences of earlier snowmelt from increased dust deposition differ from climate warming and include delayed phenology, leading to synchronized growth and flowering across the landscape and the opportunity for altered species interactions, landscape-scale gene flow via pollination, and nutrient cycling.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. A Novel Sensing Method and Sensing Algorithm Development for a Ubiquitous Network

    PubMed Central

    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. PMID:22163645

  5. 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.

  6. Development of a Decompression Algorithm for Constant 0.7 ATA Oxygen Partial Pressure in Helium Diving.

    DTIC Science & Technology

    1985-04-01

    HVAL02 140/15 ( 1 ) Hips, costo -vertebral Joints, costo -chondral junctions. 4 Bin Hip pain gone by 5 min at 60 FSW. All other Symptoms gone upon...AD-A158 142 UNCLASSIFIED DEVELOPMENT OF A DECOMPRESSION ALGORITHM FOR CONSTANT 1 /Jt 97 ATA OXVGEN PARTI.. <U> NAVY EXPERIMENTAL DIVING UNIT...PANAMA CITV FL E D THALMANN APR 85 NEDU- 1 -85 F/G 6/19 NL T i i •• » 1.1.1« j*. .*••’ ’*• J ’ ’*"’" -f" ll til5 |M 2-5 •• 2

  7. 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

  8. Development and laboratory verification of control algorithms for formation flying configuration with a single-input control

    NASA Astrophysics Data System (ADS)

    Ovchinnikov, M.; Bindel, D.; Ivanov, D.; Smirnov, G.; Theil, S.; Zaramenskikh, I.

    2010-11-01

    Once been orbited, the technological nanosatellite TNS-0 no. 1 is supposed to be used in one of the next missions for the demonstration of orbital maneuvering capability to eliminate a secular relative motion of two satellites due to the J2 harmonic of the Earth gravitational field. It is assumed that the longitudinal axis of the satellite is stabilized along the induction vector of the geomagnetic field and a thruster engine is installed along this axis. Continuous and impulsive thruster control algorithms eliminating the secular relative motion have been developed. Special equipment was developed in ZARM for demonstration and laboratory testing of the satellite motion identification and control algorithms. The facility consists of a horizontal smooth table and mobile mock-up that enables to glide over the table surface due to compressed air stored in on-board pressure tanks. Compressed air is used to control the translation and attitude motion of the mock-up equipped with a number of pulse thrusters. In this work a dynamic model for mock-up controlled motion over the table is developed. This allows us to simulate a relative motion of a pair of TNS-0 type nanosatellites in the plane of the orbit.

  9. 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

  10. 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.

  11. Modeling design iteration in product design and development and its solution by a novel artificial bee colony algorithm.

    PubMed

    Chen, Tinggui; Xiao, Renbin

    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.

  12. Object detection is completed earlier than object categorization: evidence from LRP and N200.

    PubMed

    Li, You; Zhong, Weifang; Chen, Qi; Mo, Lei

    2013-12-01

    The classic account of object recognition, which proposes that object detection precedes categorization, was challenged by recent behavioral evidence. The present study investigated the temporal relation between object detection and categorization by employing ERP measures. Participants performed a dual-choice go/no-go task based on the outcomes of object detection and categorization. A no-go lateralized readiness potential, which indexed motor preparation, was obtained only when detection determined responding hand and categorization determined go/no-go, indicating that detection was completed earlier and thus activated preparation. Additionally, the N200 effect, which indicated the completion of go/no-go, was obtained 70 ms earlier when detection determined go/no-go than when categorization determined go/no-go. Our ERP results indicate that object detection is completed earlier than categorization, which supports the traditional models of object recognition.

  13. Later endogenous circadian temperature nadir relative to an earlier wake time in older people

    NASA Technical Reports Server (NTRS)

    Duffy, J. F.; Dijk, D. J.; Klerman, E. B.; Czeisler, C. A.

    1998-01-01

    The contribution of the circadian timing system to the age-related advance of sleep-wake timing was investigated in two experiments. In a constant routine protocol, we found that the average wake time and endogenous circadian phase of 44 older subjects were earlier than that of 101 young men. However, the earlier circadian phase of the older subjects actually occurred later relative to their habitual wake time than it did in young men. These results indicate that an age-related advance of circadian phase cannot fully account for the high prevalence of early morning awakening in healthy older people. In a second study, 13 older subjects and 10 young men were scheduled to a 28-h day, such that they were scheduled to sleep at many circadian phases. Self-reported awakening from scheduled sleep episodes and cognitive throughput during the second half of the wake episode varied markedly as a function of circadian phase in both groups. The rising phase of both rhythms was advanced in the older subjects, suggesting an age-related change in the circadian regulation of sleep-wake propensity. We hypothesize that under entrained conditions, these age-related changes in the relationship between circadian phase and wake time are likely associated with self-selected light exposure at an earlier circadian phase. This earlier exposure to light could account for the earlier clock hour to which the endogenous circadian pacemaker is entrained in older people and thereby further increase their propensity to awaken at an even earlier time.

  14. Improving our understanding of flood forecasting using earlier hydro-meteorological intelligence

    NASA Astrophysics Data System (ADS)

    Shih, Dong-Sin; Chen, Cheng-Hsin; Yeh, Gour-Tsyh

    2014-05-01

    In recent decades, Taiwan has suffered from severe bouts of torrential rain, and typhoon induced floods have become the major natural threat to Taiwan. In order to warn the public of potential risks, authorities are considering establishing an early warning system derived from an integrated hydro-meteorological estimation process. This study aims at the development and accuracy of such a warning system. So it is first necessary to understand the distinctive features of flood forecasting in integrated rainfall-runoff simulations. Additionally the adequacies of a warning system that is based on extracting useful intelligence from earlier, possibly faulty numerical simulation results are discussed. In order to precisely model flooding, hydrological simulations based upon spot measured rainfall data have been utilized in prior studies to calibrate model parameters. Here, precipitation inputs from an ensemble of almost 20 different realizations of rainfall fields have been used to derive flood forecasts. The flood warning system therefore integrates rainfall-runoff calculations, field observations and data assimilations. Simulation results indicate that the ensemble precipitation estimates generated by a Weather Research Forecasting (WRF) mesoscale model produce divergent estimates. Considerable flooding is often shown in the simulated hydrographs, but the results as to the peak time and peak stage are not always in agreement with the observations. In brief, such forecasts can be good for warning against potential damaging floods in the near future, but the meteorological inputs are not good enough to forecast the time and magnitude of the peaks. The key for such warning system is not to expect highly accurate rainfall predictions, but to improve our understanding from individual ensemble flood forecasts.

  15. 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

  16. Screening Retinopathy of Prematurity in Extremely Low Birth Weight Infants in China and the Need for Earlier Screening Times

    PubMed Central

    Wang, Jianxun; Chen, Feng; He, Shiping

    2016-01-01

    Purpose. To convey the need for a revised screening strategy for retinopathy of prematurity (ROP) for extremely low birth weight (ELBW) infants in China. Design. A retrospective longitudinal study. Methods. The medical charts of infants with a birth weight (BW) of less than 1 kg were reviewed. The infants were divided into three groups: group A, without ROP; group B, with ROP but not up to type 1 prethreshold or threshold ROP; group C, with type 1 prethreshold or threshold ROP. Data collected included gender, gestational age (GA), BW, postmenstrual age (PMA), age of onset of ROP, and age at which treatment was carried out, if required. Results. A total of 77 infants were involved. Fifty-six infants developed ROP at any stage and 38 infants developed type 1 prethreshold or threshold ROP. The mean BW and GA of infants in group A were significantly different compared with groups B and C. The mean PMA of onset of ROP in infants who developed mild ROP was 37 weeks compared with 34 weeks for infants who developed severe ROP. Conclusion. ELBW infants have a higher incidence of ROP in China which highlights the need for optimizing neonatal care for these infants. In ELBW infants, ROP tends to develop more severely when it occurs earlier. It is necessary for ELBW infants, especially for those with a BW less than 800 g or a GA less than 25 weeks, to be initially screened at an earlier time. PMID:28116141

  17. 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.

  18. [Patient Satisfaction after Pitch Elevation and Development of a Therapy Algorithm].

    PubMed

    Meister, J; Kuehn, H; Shehata-Dieler, W; Kraus, F; Hagen, R; Kleinsasser, N

    2016-11-01

    Objective: Voice feminization is an important step in the therapy of male-to-female transsexualism. Approaches are conservative voice therapy and surgical interventions. The most powerful parameter of gender perception is the fundamental frequency. Besides the vocal pitch, there are other parameters influencing gender perception of a voice, e. g. intonation, prosody or formant frequencies. Material and methods: In 21 male to female transgender persons after surgical elevation of the vocal pitch the Voice Handicap Index (VHI), the Life Satisfaction Questionnaire (FLZ) and a new addendum were used. A new algorithm for voice feminization in male-to-female transsexualism was deduced. Results: After elevation of the vocal pitch, the self-confidence of the male-to-female transgender persons has increased. Despite of an elevated pitch some persons were not satisfied with their voice. Conclusion: Surgical intervention changes only the pitch of a voice. To change other parameters, conservative voice therapy is necessary. If the transgender persons are able to reach a satisfying female voice with conservative voice therapy alone, surgical intervention is not indicated.

  19. Facilitation of Third-party Development of Advanced Algorithms for Explosive Detection Using Workshops and Grand Challenges

    SciTech Connect

    Martz, H E; Crawford, C R; Beaty, J S; Castanon, D

    2011-02-15

    The US Department of Homeland Security (DHS) has requirements for future explosive detection scanners that include dealing with a larger number of threats, higher probability of detection, lower false alarm rates and lower operating costs. One tactic that DHS is pursuing to achieve these requirements is to augment the capabilities of the established security vendors with third-party algorithm developers. The purposes of this presentation are to review DHS's objectives for involving third parties in the development of advanced algorithms and then to discuss how these objectives are achieved using workshops and grand challenges. Terrorists are still trying and they are getting more sophisticated. There is a need to increase the number of smart people working on homeland security. Augmenting capabilities and capacities of system vendors with third-parties is one tactic. Third parties can be accessed via workshops and grand challenges. Successes have been achieved to date. There are issues that need to be resolved to further increase third party involvement.

  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. Development of a Reduction Algorithm of GEO Satellite Optical Observation Data for Optical Wide Field Patrol (OWL)

    NASA Astrophysics Data System (ADS)

    Park, Sun-youp; Choi, Jin; Jo, Jung Hyun; Son, Ju Young; Park, Yung-Sik; Yim, Hong-Suh; Moon, Hong-Kyu; Bae, Young-Ho; Choi, Young-Jun; Park, Jang-Hyun

    2015-09-01

    An algorithm to automatically extract coordinate and time information from optical observation data of geostationary orbit satellites (GEO satellites) or geosynchronous orbit satellites (GOS satellites) is developed. The optical wide-field patrol system is capable of automatic observation using a pre-arranged schedule. Therefore, if this type of automatic analysis algorithm is available, daily unmanned monitoring of GEO satellites can be possible. For data acquisition for development, the COMS1 satellite was observed with 1-s exposure time and 1-m interval. The images were grouped and processed in terms of ¡°action¡±, and each action was composed of six or nine successive images. First, a reference image with the best quality in one action was selected. Next, the rest of the images in the action were geometrically transformed to fit in the horizontal coordinate system (expressed in azimuthal angle and elevation) of the reference image. Then, these images were median-combined to retain only the possible non-moving GEO candidates. By reverting the coordinate transformation of the positions of these GEO satellite candidates, the final coordinates could be calculated.

  2. Development of an algorithm to regulate pump output for a closed air-loop type pneumatic biventricular assist device.

    PubMed

    Nam, Kyoung Won; Lee, Jung Joo; Hwang, Chang Mo; Choi, Jaesoon; Choi, Hyuk; Choi, Seong Wook; Sun, Kyung

    2009-12-01

    The closed air space-type of extracorporeal pneumatic ventricular assist device (VAD) developed by the Korea Artificial Organ Center utilizes a bellows-transforming mechanism to generate the air pressure required to pump blood. This operating mechanism can reduce the size and weight of the driving unit; however, the output of the blood pump can be affected by the pressure loading conditions of the blood sac. Therefore, to guarantee a proper pump output level, regardless of the pressure loading conditions that vary over time, automatic pump output regulation of the blood pump is required. We describe herein a pump output regulation algorithm that was developed to maintain pump output around a reference level against various afterload pressures, and verified the pump performance in vitro. Based on actual operating conditions in animal experiments, the pumping rate was limited to 40-84 beats per minute, and the afterload pressure was limited to 80-150 mm Hg. The tested reference pump output was 4.0 L/min. During experiments, the pump output was successfully and automatically regulated within the preset area regardless of the varying afterload conditions. The results of this preliminary experiment can be used as the basis for an automatic control algorithm that can enhance the stability and reliability of the applied VAD.

  3. 75 FR 47316 - National Science Board; Sunshine Act Meetings; Notice (Subject Matter Revised From Earlier Notice)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... National Science Board; Sunshine Act Meetings; Notice (Subject Matter Revised From Earlier Notice) The... National Science Board business and other matters specified, as follows: Date and Time: August 12, 2010, at 3 p.m. EDT. Subject Matter: Review and Discussion of Current Mid-Scale Research Funding Support...

  4. Tidal Wave II Revisited: A Review of Earlier Enrollment Projections for California Higher Education.

    ERIC Educational Resources Information Center

    Hayward, Gerald C.; Breneman, David W.; Estrada, Leobardo F.

    This report examined enrollment projections for higher education institutions in California in relation to earlier projections conducted in the mid-1990s that forecasted steep declines in enrollment. It notes that California's remarkable economic recovery over the last several years has allowed it to fund higher education enrollment growth at a…

  5. 40 CFR 87.21 - Exhaust emission standards for Tier 4 and earlier engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES Exhaust Emissions (New Aircraft Gas Turbine Engines) § 87.21 Exhaust emission standards for Tier 4 and earlier... apply for aircraft engines manufactured before July 18, 2012 and certain engines exempted under §...

  6. 40 CFR 87.21 - Exhaust emission standards for Tier 4 and earlier engines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES Exhaust Emissions (New Aircraft Gas Turbine Engines) § 87.21 Exhaust emission standards for Tier 4 and earlier... apply for aircraft engines manufactured before July 18, 2012 and certain engines exempted under §...

  7. Left ventricular pseudoaneurysm found after mitral valve replacement performed 30 years earlier.

    PubMed

    Castilla, Elena; Gato, Manuel; Ruiz, José Ramón

    2010-03-01

    Pseudoaneurysm of the left ventricle (LV) is a rare cardiac disease that occurs after myocardial infarction or cardiac surgery. Because patients frequently present with nonspecific symptoms, a high index of suspicion is needed to make the diagnosis. This report describes an unusual case demonstrating a large LV pseudoaneurysm after mitral valve replacement performed 30 years earlier.

  8. Preliminary evaluation of the Environmental Research Institute of Michigan crop calendar shift algorithm for estimation of spring wheat development stage. [North Dakota, South Dakota, Montana, and Minnesota

    NASA Technical Reports Server (NTRS)

    Phinney, D. E. (Principal Investigator)

    1980-01-01

    An algorithm for estimating spectral crop calendar shifts of spring small grains was applied to 1978 spring wheat fields. The algorithm provides estimates of the date of peak spectral response by maximizing the cross correlation between a reference profile and the observed multitemporal pattern of Kauth-Thomas greenness for a field. A methodology was developed for estimation of crop development stage from the date of peak spectral response. Evaluation studies showed that the algorithm provided stable estimates with no geographical bias. Crop development stage estimates had a root mean square error near 10 days. The algorithm was recommended for comparative testing against other models which are candidates for use in AgRISTARS experiments.

  9. Genetic algorithm guided population pharmacokinetic model development for simvastatin, concurrently or non-concurrently co-administered with amlodipine.

    PubMed

    Chaturvedula, Ayyappa; Sale, Mark E; Lee, Howard

    2014-02-01

    An automated model development was performed for simvastatin, co-administered with amlodipine concurrently or non-concurrently (i.e., 4 hours later) in 17 patients with coexisting hyperlipidemia and hypertension. The single objective hybrid genetic algorithm (SOHGA) was implemented in the NONMEM software by defining the search space for structural, statistical and covariate models. Candidate models obtained from the SOHGA runs were further assessed for biological plausibility and the precision of parameter estimates, followed by traditional backward elimination process for model refinement. The final population pharmacokinetic model shows that the elimination rate constant for simvastatin acid, the active form by hydrolysis of its lactone prodrug (i.e., simvastatin), is only 44% in the concurrent amlodipine administration group compared with the non-concurrent group. The application of SOHGA for automated model selection, combined with traditional model selection strategies, appears to save time for model development, which also can generate new hypotheses that are biologically more plausible.

  10. Earlier springs decrease peak summer productivity in North American boreal forests

    NASA Astrophysics Data System (ADS)

    Buermann, Wolfgang; Bikash, Parida R.; Jung, Martin; Burn, Donald H.; Reichstein, Markus

    2013-06-01

    In the northern high latitudes, alternative hypotheses with regards to how warming-related shifts in seasonality influence ecosystem productivity exist. Increased plant growth associated with a longer growing season may enhance ecosystem productivity, but shifts to earlier springs may also negatively influence soil moisture status and productivity during the peak of the growing season. Here, we analyzed nearly three decades (1982-2008) of observational records and derived products, including satellite microwave and optical imagery as well as upscaled ecosystem flux observations, to better understand how shifts in seasonality impact hydrology and productivity in the North American boreal forests. We identified a dominant adverse influence of earlier springs on peak summer forest greenness, actual evapotranspiration and productivity at interannual time scales across the drier western and central sections of the North American boreal forests. In the vast regions where this spring onset mechanism operates, ecosystem productivity gains from earlier springs during the early portion of the growing season are effectively cancelled through corresponding losses in the later portion. Our results also indicate that recent decadal shifts towards earlier springs and associated drying in the midst of the growing season over western North American boreal forests may have contributed to the reported declines in summer productivity and increases in tree mortality and fire activity. With projections of accelerated northern high-latitude warming and associated shifts to earlier springs, persistent soil moisture deficits in peak summer may be an effective mechanism for regional-scale boreal forest dieback through their strong influence on productivity, tree mortality and disturbance dynamics.

  11. Genetic algorithm optimization of point charges in force field development: challenges and insights.

    PubMed

    Ivanov, Maxim V; Talipov, Marat R; Timerghazin, Qadir K

    2015-02-26

    Evolutionary methods, such as genetic algorithms (GAs), provide powerful tools for optimization of the force field parameters, especially in the case of simultaneous fitting of the force field terms against extensive reference data. However, GA fitting of the nonbonded interaction parameters that includes point charges has not been explored in the literature, likely due to numerous difficulties with even a simpler problem of the least-squares fitting of the atomic point charges against a reference molecular electrostatic potential (MEP), which often demonstrates an unusually high variation of the fitted charges on buried atoms. Here, we examine the performance of the GA approach for the least-squares MEP point charge fitting, and show that the GA optimizations suffer from a magnified version of the classical buried atom effect, producing highly scattered yet correlated solutions. This effect can be understood in terms of the linearly independent, natural coordinates of the MEP fitting problem defined by the eigenvectors of the least-squares sum Hessian matrix, which are also equivalent to the eigenvectors of the covariance matrix evaluated for the scattered GA solutions. GAs quickly converge with respect to the high-curvature coordinates defined by the eigenvectors related to the leading terms of the multipole expansion, but have difficulty converging with respect to the low-curvature coordinates that mostly depend on the buried atom charges. The performance of the evolutionary techniques dramatically improves when the point charge optimization is performed using the Hessian or covariance matrix eigenvectors, an approach with a significant potential for the evolutionary optimization of the fixed-charge biomolecular force fields.

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

    NASA Technical Reports Server (NTRS)

    Gordan, Howard R.

    1996-01-01

    Several significant accomplishments were made during the present reporting period. We have completed our basic study of using the 1.38 micron MODIS band for removal of the effects of thin cirrus clouds and stratospheric aerosol. The results suggest that it should be possible to correct imagery for thin cirrus clouds with optical thicknesses as large as 0.5 to 1.0. We have also acquired reflectance data for oceanic whitecaps during a cruise on the RV Malcolm Baldrige in the Gulf of Mexico. 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. We installed a CIMEL sun photometer at Fort Jefferson on the Dry Tortugas off Key West in the Gulf of Mexico. The instrument has yielded a continuous stream of data since February. It shows that the aerosol optical thickness at 669 nm is often less than 0.1 in winter. This suggests that the Southern Gulf of Mexico will be an excellent winter site for vicarious calibration. In addition, we completed a study of the effect of vicarious calibration, i.e., the accuracy with which the radiance at the top of the atmosphere (TOA) can be predicted from measurement of the sky radiance at the bottom of the atmosphere (BOA). The results suggest that the neglect of polarization in the aerosol optical property inversion algorithm and in the prediction code for the TOA radiances is the largest error associated with the radiative transfer process. Overall, the study showed that the accuracy of the TOA radiance prediction is now limited by the racliometric calibration error in the sky radiometer. Finally, considerable coccolith light scattering data were obtained in the Gulf of Maine with a flow-through instrument, along with data relating to calcite concentration and the rate of calcite production.

  13. Development of a Geant4 based Monte Carlo Algorithm to evaluate the MONACO VMAT treatment accuracy.

    PubMed

    Fleckenstein, Jens; Jahnke, Lennart; Lohr, Frank; Wenz, Frederik; Hesser, Jürgen

    2013-02-01

    A method to evaluate the dosimetric accuracy of volumetric modulated arc therapy (VMAT) treatment plans, generated with the MONACO™ (version 3.0) treatment planning system in realistic CT-data with an independent Geant4 based dose calculation algorithm is presented. Therefore a model of an Elekta Synergy linear accelerator treatment head with an MLCi2 multileaf collimator was implemented in Geant4. The time dependent linear accelerator components were modeled by importing either logfiles of an actual plan delivery or a DICOM-RT plan sequence. Absolute dose calibration, depending on a reference measurement, was applied. The MONACO as well as the Geant4 treatment head model was commissioned with lateral profiles and depth dose curves of square fields in water and with film measurements in inhomogeneous phantoms. A VMAT treatment plan for a patient with a thoracic tumor and a VMAT treatment plan of a patient, who received treatment in the thoracic spine region including metallic implants, were used for evaluation. MONACO, as well as Geant4, depth dose curves and lateral profiles of square fields had a mean local gamma (2%, 2mm) tolerance criteria agreement of more than 95% for all fields. Film measurements in inhomogeneous phantoms with a global gamma of (3%, 3mm) showed a pass rate above 95% in all voxels receiving more than 25% of the maximum dose. A dose-volume-histogram comparison of the VMAT patient treatment plans showed mean deviations between Geant4 and MONACO of -0.2% (first patient) and 2.0% (second patient) for the PTVs and (0.5±1.0)% and (1.4±1.1)% for the organs at risk in relation to the prescription dose. The presented method can be used to validate VMAT dose distributions generated by a large number of small segments in regions with high electron density gradients. The MONACO dose distributions showed good agreement with Geant4 and film measurements within the simulation and measurement errors.

  14. Algorithms for Zonal Methods and Development of Three Dimensional Mesh Generation Procedures.

    DTIC Science & Technology

    1984-02-01

    of three dimensional grid generation both elliptic and hyper- bolic methods were developed. A chimera grid scheme, that is, the use of overset multiple...were developed. A chimera grid scheme, that is, the use of overset multiple grid systems, was also tested in two dimensions. In our study of zonal...Background . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. Grid Generation ............................... 2 3. Overset Grids

  15. Development of a Comprehensive Human Immunodeficiency Virus Type 1 Screening Algorithm for Discovery and Preclinical Testing of Topical Microbicides▿

    PubMed Central

    Lackman-Smith, Carol; Osterling, Clay; Luckenbaugh, Katherine; Mankowski, Marie; Snyder, Beth; Lewis, Gareth; Paull, Jeremy; Profy, Albert; Ptak, Roger G.; Buckheit, Robert W.; Watson, Karen M.; Cummins, James E.; Sanders-Beer, Brigitte E.

    2008-01-01

    Topical microbicides are self-administered, prophylactic products for protection against sexually transmitted pathogens. A large number of compounds with known anti-human immunodeficiency virus type 1 (HIV-1) inhibitory activity have been proposed as candidate topical microbicides. To identify potential leads, an in vitro screening algorithm was developed to evaluate candidate microbicides in assays that assess inhibition of cell-associated and cell-free HIV-1 transmission, entry, and fusion. The algorithm advances compounds by evaluation in a series of defined assays that generate measurements of relative antiviral potency to determine advancement or failure. Initial testing consists of a dual determination of inhibitory activity in the CD4-dependent CCR5-tropic cell-associated transmission inhibition assay and in the CD4/CCR5-mediated HIV-1 entry assay. The activity is confirmed by repeat testing, and identified actives are advanced to secondary screens to determine their effect on transmission of CXCR4-tropic viruses in the presence or absence of CD4 and their ability to inhibit CXCR4- and CCR5-tropic envelope-mediated cell-to-cell fusion. In addition, confirmed active compounds are also evaluated in the presence of human seminal plasma, in assays incorporating a pH 4 to 7 transition, and for growth inhibition of relevant strains of lactobacilli. Leads may then be advanced for specialized testing, including determinations in human cervical explants and in peripheral blood mononuclear cells against primary HIV subtypes, combination testing with other inhibitors, and additional cytotoxicity assays. PRO 2000 and SPL7013 (the active component of VivaGel), two microbicide products currently being evaluated in human clinical trials, were tested in this in vitro algorithm and were shown to be highly active against CCR5- and CXCR4-tropic HIV-1 infection. PMID:18316528

  16. Clustering algorithm studies

    NASA Astrophysics Data System (ADS)

    Graf, Norman A.

    2001-07-01

    An object-oriented framework for undertaking clustering algorithm studies has been developed. We present here the definitions for the abstract Cells and Clusters as well as the interface for the algorithm. We intend to use this framework to investigate the interplay between various clustering algorithms and the resulting jet reconstruction efficiency and energy resolutions to assist in the design of the calorimeter detector.

  17. Thermal algorithms analysis. [programming tasks supporting the development of a thermal model of the Earth's surface

    NASA Technical Reports Server (NTRS)

    Lien, T.

    1981-01-01

    The programming and analysis methods to support the development of a thermal model of the Earth's surface from detailed analysis of day/night registered data sets from the Heat Capacity Mapping Mission satellite are briefly described.

  18. Development and validation of a MODIS colored dissolved organic matter (CDOM) algorithm in northwest Florida estuaries

    EPA Science Inventory

    Satellite remote sensing provides synoptic and frequent monitoring of water quality parameters that aids in determining the health of aquatic ecosystems and the development of effective management strategies. Northwest Florida estuaries are classified as optically-complex, or wat...

  19. High-resolution computational algorithms for simulating offshore wind turbines and farms: Model development and validation

    SciTech Connect

    Calderer, Antoni; Yang, Xiaolei; Angelidis, Dionysios; Feist, Chris; Guala, Michele; Ruehl, Kelley; Guo, Xin; Boomsma, Aaron; Shen, Lian; Sotiropoulos, Fotis

    2015-10-30

    The present project involves the development of modeling and analysis design tools for assessing offshore wind turbine technologies. The computational tools developed herein are able to resolve the effects of the coupled interaction of atmospheric turbulence and ocean waves on aerodynamic performance and structural stability and reliability of offshore wind turbines and farms. Laboratory scale experiments have been carried out to derive data sets for validating the computational models.

  20. The mass-action law based algorithm for cost-effective approach for cancer drug discovery and development

    PubMed Central

    Chou, Ting-Chao

    2011-01-01

    The mass-action law based system analysis via mathematical induction and deduction lead to the generalized theory and algorithm that allows computerized simulation of dose-effect dynamics with small size experiments using a small number of data points in vitro, in animals, and in humans. The median-effect equation of the mass-action law deduced from over 300 mechanism specific-equations has been shown to be the unified theory that serves as the common-link for complicated biomedical systems. After using the median-effect principle as the common denominator, its applications are mechanism-independent, drug unit-independent, and dynamic order-independent; and can be used generally for single drug analysis or for multiple drug combinations in constant-ratio or non-constant ratios. Since the “median” is the common link and universal reference point in biological systems, these general enabling lead to computerized quantitative bio-informatics for econo-green bio-research in broad disciplines. Specific applications of the theory, especially relevant to drug discovery, drug combination, and clinical trials, have been cited or illustrated in terms of algorithms, experimental design and computerized simulation for data analysis. Lessons learned from cancer research during the past fifty years provide a valuable opportunity to reflect, and to improve the conventional divergent approach and to introduce a new convergent avenue, based on the mass-action law principle, for the efficient cancer drug discovery and the low-cost drug development. PMID:22016837

  1. Preliminary results of real-time PPP-RTK positioning algorithm development for moving platforms and its performance validation

    NASA Astrophysics Data System (ADS)

    Won, Jihye; Park, Kwan-Dong

    2015-04-01

    Real-time PPP-RTK positioning algorithms were developed for the purpose of getting precise coordinates of moving platforms. In this implementation, corrections for the satellite orbit and satellite clock were taken from the IGS-RTS products while the ionospheric delay was removed through ionosphere-free combination and the tropospheric delay was either taken care of using the Global Pressure and Temperature (GPT) model or estimated as a stochastic parameter. To improve the convergence speed, all the available GPS and GLONASS measurements were used and Extended Kalman Filter parameters were optimized. To validate our algorithms, we collected the GPS and GLONASS data from a geodetic-quality receiver installed on a roof of a moving vehicle in an open-sky environment and used IGS final products of satellite orbits and clock offsets. The horizontal positioning error got less than 10 cm within 5 minutes, and the error stayed below 10 cm even after the vehicle start moving. When the IGS-RTS product and the GPT model were used instead of the IGS precise product, the positioning accuracy of the moving vehicle was maintained at better than 20 cm once convergence was achieved at around 6 minutes.

  2. An approach to the development of numerical algorithms for first order linear hyperbolic systems in multiple space dimensions: The constant coefficient case

    NASA Technical Reports Server (NTRS)

    Goodrich, John W.

    1995-01-01

    Two methods for developing high order single step explicit algorithms on symmetric stencils with data on only one time level are presented. Examples are given for the convection and linearized Euler equations with up to the eighth order accuracy in both space and time in one space dimension, and up to the sixth in two space dimensions. The method of characteristics is generalized to nondiagonalizable hyperbolic systems by using exact local polynominal solutions of the system, and the resulting exact propagator methods automatically incorporate the correct multidimensional wave propagation dynamics. Multivariate Taylor or Cauchy-Kowaleskaya expansions are also used to develop algorithms. Both of these methods can be applied to obtain algorithms of arbitrarily high order for hyperbolic systems in multiple space dimensions. Cross derivatives are included in the local approximations used to develop the algorithms in this paper in order to obtain high order accuracy, and improved isotropy and stability. Efficiency in meeting global error bounds is an important criterion for evaluating algorithms, and the higher order algorithms are shown to be up to several orders of magnitude more efficient even though they are more complex. Stable high order boundary conditions for the linearized Euler equations are developed in one space dimension, and demonstrated in two space dimensions.

  3. Development of algorithms for using satellite meteorological data sets to study global transport of stratospheric aerosols and ozone

    NASA Technical Reports Server (NTRS)

    Want, P. H.; Deepak, A.

    1985-01-01

    The utilization of stratospheric aerosol and ozone measurements obtained from the NASA developed SAM II and SAGE satellite instruments were investigated for their global scale transports. The stratospheric aerosols showed that during the stratospheric warming of the winter 1978 to 1979, the distribution of the zonal mean aerosol extinction ratio in the northern high latitude exhibited distinct changes. Dynamic processes might have played an important role in maintenance role in maintenance of this zonal mean distribution. As to the stratospheric ozone, large poleward ozone transports are shown to occur in the altitude region from 24 km to 38 km near 55N during this warming. This altitude region is shown to be a transition region of the phase relationship between ozone and temperature waves from an in-phase one above 38 km. It is shown that the ozone solar heating in the upper stratosphere might lead to enhancement of the damping rate of the planetary waves due to infrared radiation alone in agreement with theoretical analyses and an earlier observational study.

  4. Quantum algorithms: an overview

    NASA Astrophysics Data System (ADS)

    Montanaro, Ashley

    2016-01-01

    Quantum computers are designed to outperform standard computers by running quantum algorithms. Areas in which quantum algorithms can be applied include cryptography, search and optimisation, simulation of quantum systems and solving large systems of linear equations. Here we briefly survey some known quantum algorithms, with an emphasis on a broad overview of their applications rather than their technical details. We include a discussion of recent developments and near-term applications of quantum algorithms.

  5. INSENS classification algorithm report

    SciTech Connect

    Hernandez, J.E.; Frerking, C.J.; Myers, D.W.

    1993-07-28

    This report describes a new algorithm developed for the Imigration and Naturalization Service (INS) in support of the INSENS project for classifying vehicles and pedestrians using seismic data. This algorithm is less sensitive to nuisance alarms due to environmental events than the previous algorithm. Furthermore, the algorithm is simple enough that it can be implemented in the 8-bit microprocessor used in the INSENS system.

  6. Continued Research into Characterizing the Preturbulence Environment for Sensor Development, New Hazard Algorithms and Experimental Flight Planning

    NASA Technical Reports Server (NTRS)

    Kaplan, Michael L.; Lin, Yuh-Lang

    2005-01-01

    The purpose of the research was to develop and test improved hazard algorithms that could result in the development of sensors that are better able to anticipate potentially severe atmospheric turbulence, which affects aircraft safety. The research focused on employing numerical simulation models to develop improved algorithms for the prediction of aviation turbulence. This involved producing both research simulations and real-time simulations of environments predisposed to moderate and severe aviation turbulence. The research resulted in the following fundamental advancements toward the aforementioned goal: 1) very high resolution simulations of turbulent environments indicated how predictive hazard indices could be improved resulting in a candidate hazard index that indicated the potential for improvement over existing operational indices, 2) a real-time turbulence hazard numerical modeling system was improved by correcting deficiencies in its simulation of moist convection and 3) the same real-time predictive system was tested by running the code twice daily and the hazard prediction indices updated and improved. Additionally, a simple validation study was undertaken to determine how well a real time hazard predictive index performed when compared to commercial pilot observations of aviation turbulence. Simple statistical analyses were performed in this validation study indicating potential skill in employing the hazard prediction index to predict regions of varying intensities of aviation turbulence. Data sets from a research numerical model where provided to NASA for use in a large eddy simulation numerical model. A NASA contractor report and several refereed journal articles where prepared and submitted for publication during the course of this research.

  7. The Algorithm of Development the World Ocean Mining of the Industry During the Global Crisis

    NASA Astrophysics Data System (ADS)

    Nyrkov, Anatoliy; Budnik, Vladislav; Sokolov, Sergei; Chernyi, Sergei

    2016-08-01

    In the article reviewed extraction effect of hydrocarbons on the general country's developing, under the impact of economical, demographical and technological factors, as well as it's future role in the world energy balance. Also adduced facts which designate offshore and deep water production of unconventional and conventional hydrocarbons including mining of marine mineral resources as perspective area of development in the future, despite all the difficulties of this sector. In the article considered the state and prospects of the Russian continental shelf, in consideration of its geographical location and its all existing problems.

  8. Development and Performance of an Algorithm to Estimate the Child-Turcotte-Pugh Score From a National Electronic Healthcare Database

    PubMed Central

    Kaplan, David E.; Dai, Feng; Aytaman, Ayse; Baytarian, Michelle; Fox, Rena; Hunt, Kristel; Knott, Astrid; Pedrosa, Marcos; Pocha, Christine; Mehta, Rajni; Duggal, Mona; Skanderson, Melissa; Valderrama, Adriana; Taddei, Tamar

    2015-01-01

    BACKGROUND & METHODS The Child-Turcotte-Pugh (CTP) score is a widely used and validated predictor of long-term survival in cirrhosis. The CTP score is a composite of 5 subscores, 3 based on objective clinical laboratory values and 2 subjective variables quantifying the severity of ascites and hepatic encephalopathy. To date, no system to quantify CTP score from administrative databases has been validated. The Veterans Outcomes and Costs Associated with Liver Disease study is a multicenter collaborative study to evaluate the outcomes and costs of hepatocellular carcinoma in the U.S. Veterans Health Administration. We developed and validated an algorithm to calculate electronic CTP (eCTP) scores by using data from the Veterans Health Administration Corporate Data Warehouse. METHODS Multiple algorithms for determining each CTP subscore from International Classification of Diseases version 9, Common Procedural Terminology, pharmacy, and laboratory data were devised and tested in 2 patient cohorts. For each cohort, 6 site investigators (Boston, Bronx, Brooklyn, Philadelphia, Minneapolis, and West Haven VA Medical Centers) were provided cases from which to determine validity of diagnosis, laboratory data, and clinical assessment of ascites and encephalopathy. The optimal algorithm (designated eCTP) was then applied to 30,840 cirrhotic patients alive in the first quarter of 2008 for whom 5-year overall and transplant-free survival data were available. The ability of the eCTP score and other disease severity scores (Charlson-Deyo index, Veterans Aging Cohort Study index, Model for End-Stage Liver Disease score, and Cirrhosis Comorbidity) to predict survival was then assessed by Cox proportional hazards regression. RESULTS Spearman correlations for administrative and investigator validated laboratory data in the HCC and cirrhotic cohorts, respectively, were 0.85 and 0.92 for bilirubin, 0.92 and 0.87 for albumin, and 0.84 and 0.86 for international normalized ratio. In the

  9. Observed shift towards earlier spring discharge in the main Alpine rivers.

    PubMed

    Zampieri, Matteo; Scoccimarro, Enrico; Gualdi, Silvio; Navarra, Antonio

    2015-01-15

    In this study, we analyse the observed long-term discharge time-series of the Rhine, the Danube, the Rhone and the Po rivers. These rivers are characterised by different seasonal cycles reflecting the diverse climates and morphologies of the Alpine basins. However, despite the intensive and varied water management adopted in the four basins, we found common features in the trend and low-frequency variability of the spring discharge timings. All the discharge time-series display a tendency towards earlier spring peaks of more than two weeks per century. These results can be explained in terms of snowmelt, total precipitation (i.e. the sum of snowfall and rainfall) and rainfall variability. The relative importance of these factors might be different in each basin. However, we show that the change of seasonality of total precipitation plays a major role in the earlier spring runoff over most of the Alps.

  10. Compulsive buying: Earlier illicit drug use, impulse buying, depression, and adult ADHD symptoms.

    PubMed

    Brook, Judith S; Zhang, Chenshu; Brook, David W; Leukefeld, Carl G

    2015-08-30

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant's earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB.

  11. A Vantage from Space Can Detect Earlier Drought Onset: An Approach Using Relative Humidity

    PubMed Central

    Farahmand, Alireza; AghaKouchak, Amir; Teixeira, Joao

    2015-01-01

    Each year, droughts cause significant economic and agricultural losses across the world. The early warning and onset detection of drought is of particular importance for effective agriculture and water resource management. Previous studies show that the Standard Precipitation Index (SPI), a measure of precipitation deficit, detects drought onset earlier than other indicators. Here we show that satellite-based near surface air relative humidity data can further improve drought onset detection and early warning. This paper introduces the Standardized Relative Humidity Index (SRHI) based on the NASA Atmospheric Infrared Sounder (AIRS) observations. The results indicate that the SRHI typically detects the drought onset earlier than the SPI. While the AIRS mission was not originally designed for drought monitoring, we show that its relative humidity data offers a new and unique avenue for drought monitoring and early warning. We conclude that the early warning aspects of SRHI may have merit for integration into current drought monitoring systems. PMID:25711500

  12. Peak tornado activity is occurring earlier in the heart of "Tornado Alley"

    NASA Astrophysics Data System (ADS)

    Long, John A.; Stoy, Paul C.

    2014-09-01

    Tornado frequency may increase as the factors that contribute to severe convection are altered by a changing climate. Attributing changes in tornado frequency to observed global climate change is complicated because observational effort has increased over time, but studies of the seasonal distribution of tornado activity may avoid sampling biases. We demonstrate that peak tornado activity has shifted 7 days earlier in the year over the past six decades in the central and southern US Great Plains, the area with the highest global incidence of tornado activity. Results are largely unrelated to large-scale climate oscillations, and observed climate trends cannot fully account for observations, which suggest that changes to regional climate dynamics should be further investigated. Tornado preparedness efforts at individual to national levels should be cognizant of the trend toward earlier peak tornado activity across the heart of "Tornado Alley".

  13. Compulsive Buying: Earlier Illicit Drug Use, Impulse Buying, Depression, and Adult ADHD Symptoms

    PubMed Central

    Brook, Judith S.; Zhang, Chenshu; Brook, David W.; Leukefeld, Carl G.

    2015-01-01

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant’s earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB. PMID:26165963

  14. A vantage from space can detect earlier drought onset: an approach using relative humidity.

    PubMed

    Farahmand, Alireza; AghaKouchak, Amir; Teixeira, Joao

    2015-02-25

    Each year, droughts cause significant economic and agricultural losses across the world. The early warning and onset detection of drought is of particular importance for effective agriculture and water resource management. Previous studies show that the Standard Precipitation Index (SPI), a measure of precipitation deficit, detects drought onset earlier than other indicators. Here we show that satellite-based near surface air relative humidity data can further improve drought onset detection and early warning. This paper introduces the Standardized Relative Humidity Index (SRHI) based on the NASA Atmospheric Infrared Sounder (AIRS) observations. The results indicate that the SRHI typically detects the drought onset earlier than the SPI. While the AIRS mission was not originally designed for drought monitoring, we show that its relative humidity data offers a new and unique avenue for drought monitoring and early warning. We conclude that the early warning aspects of SRHI may have merit for integration into current drought monitoring systems.

  15. Development of a Water Treatment Plant Operation Manual Using an Algorithmic Approach.

    ERIC Educational Resources Information Center

    Counts, Cary A.

    This document describes the steps to be followed in the development of a prescription manual for training of water treatment plant operators. Suggestions on how to prepare both flow and narrative prescriptions are provided for a variety of water treatment systems, including: raw water, flocculation, rapid sand filter, caustic soda feed, alum feed,…

  16. From Folktales to Algorithms: Developing the Teacher's Role as Principal Storyteller in the Classroom

    ERIC Educational Resources Information Center

    Daniel, A. K.

    2007-01-01

    Whilst much thought has been given to the use of storytelling as a tool in the development of children's oral skills, little has been considered with regard to the role of the teacher as a model of good practice in storytelling, as principle storyteller in the classroom. In this paper I have tried to connect a pragmatic approach to classroom…

  17. HEAVY DUTY DIESEL VEHICLE LOAD ESTIMATION: DEVELOPMENT OF VEHICLE ACTIVITY OPTIMIZATION ALGORITHM

    EPA Science Inventory

    The Heavy-Duty Vehicle Modal Emission Model (HDDV-MEM) developed by the Georgia Institute of Technology(Georgia Tech) has a capability to model link-specific second-by-second emissions using speed/accleration matrices. To estimate emissions, engine power demand calculated usin...

  18. Scheduling language and algorithm development study. Volume 1: Study summary and overview

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A high level computer programming language and a program library were developed to be used in writing programs for scheduling complex systems such as the space transportation system. The objectives and requirements of the study are summarized and unique features of the specified language and program library are described and related to the why of the objectives and requirements.

  19. A Review of Quality of Life after Predictive Testing for and Earlier Identification of Neurodegenerative Diseases

    PubMed Central

    Paulsen, Jane S.; Nance, Martha; Kim, Ji-In; Carlozzi, Noelle E.; Panegyres, Peter K.; Erwin, Cheryl; Goh, Anita; McCusker, Elizabeth; Williams, Janet K.

    2013-01-01

    The past decade has witnessed an explosion of evidence suggesting that many neurodegenerative diseases can be detected years, if not decades, earlier than previously thought. To date, these scientific advances have not provoked any parallel translational or clinical improvements. There is an urgency to capitalize on this momentum so earlier detection of disease can be more readily translated into improved health-related quality of life for families at risk for, or suffering with, neurodegenerative diseases. In this review, we discuss health-related quality of life (HRQOL) measurement in neurodegenerative diseases and the importance of these “patient reported outcomes” for all clinical research. Next, we address HRQOL following early identification or predictive genetic testing in some neurodegenerative diseases: Huntington disease, Alzheimer's disease, Parkinson's disease, Dementia with Lewy bodies, frontotemporal dementia, amyotrophic lateral sclerosis, prion diseases, hereditary ataxias, Dentatorubral-pallidoluysian atrophy and Wilson's disease. After a brief report of available direct-to-consumer genetic tests, we address the juxtaposition of earlier disease identification with assumed reluctance towards predictive genetic testing. Forty-one studies examining health related outcomes following predictive genetic testing for neurodegenerative disease suggested that (a) extreme or catastrophic outcomes are rare; (b) consequences commonly include transiently increased anxiety and/or depression; (c) most participants report no regret; (d) many persons report extensive benefits to receiving genetic information; and (e) stigmatization and discrimination for genetic diseases are poorly understood and policy and laws are needed. Caution is appropriate for earlier identification of neurodegenerative diseases but findings suggest further progress is safe, feasible and likely to advance clinical care. PMID:24036231

  20. Variations in subject pool as a function of earlier or later participation.

    PubMed

    Bernard, L

    2000-04-01

    Data were obtained from 113 participants in a university subject pool during a 16-wk. semester. Without knowing the purpose of the study, participants self-selected to participate earlier (Weeks 3 and 4: n = 63) or later (Weeks 15 or 16) n = 50). Variations in scores on the NEO Personality Inventory--Revised, the Crowne-Marlowe Social Desirability Scale, the General Expectancy of Success Scale, the Shipley Institute of Living Scale, self-reported SATs and GPAs, and a measure of academic self-efficacy as a function of earlier or later participation were examined. Multivariate analysis of variance indicated that early participants differed significantly from later participants but not in predicted ways. Earlier participants scored higher on NEO PI-R Neuroticism; specifically men (n = 15) and women (n = 48) scored higher on Hostility, and women scored higher on Depression and Self-consciousness. An additional significant difference occurred for self-reported SAT Verbal scores for men, which were significantly higher for later participants. These temporal variations may represent confounds in research using university subject pools.

  1. Earlier-season vegetation has greater temperature sensitivity of spring phenology in northern hemisphere.

    PubMed

    Shen, Miaogen; Tang, Yanhong; Chen, Jin; Yang, Xi; Wang, Cong; Cui, Xiaoyong; Yang, Yongping; Han, Lijian; Li, Le; Du, Jianhui; Zhang, Gengxin; Cong, Nan

    2014-01-01

    In recent decades, satellite-derived start of vegetation growing season (SOS) has advanced in many northern temperate and boreal regions. Both the magnitude of temperature increase and the sensitivity of the greenness phenology to temperature-the phenological change per unit temperature-can contribute the advancement. To determine the temperature-sensitivity, we examined the satellite-derived SOS and the potentially effective pre-season temperature (T eff) from 1982 to 2008 for vegetated land between 30°N and 80°N. Earlier season vegetation types, i.e., the vegetation types with earlier SOSmean (mean SOS for 1982-2008), showed greater advancement of SOS during 1982-2008. The advancing rate of SOS against year was also greater in the vegetation with earlier SOSmean even the T eff increase was the same. These results suggest that the spring phenology of vegetation may have high temperature sensitivity in a warmer area. Therefore it is important to consider temperature-sensitivity in assessing broad-scale phenological responses to climatic warming. Further studies are needed to explore the mechanisms and ecological consequences of the temperature-sensitivity of start of growing season in a warming climate.

  2. Floodplains within reservoirs promote earlier spawning of white crappies Pomoxis annularis

    USGS Publications Warehouse

    Miranda, Leandro E.; Dagel, Jonah D.; Kaczka, Levi J.; Mower, Ethan; Wigen, S. L.

    2015-01-01

    Reservoirs impounded over floodplain rivers are unique because they may include within their upper reaches extensive shallow water stored over preexistent floodplains. Because of their relatively flat topography and riverine origin, floodplains in the upper reaches of reservoirs provide broad expanses of vegetation within a narrow range of reservoir water levels. Elsewhere in the reservoir, topography creates a band of shallow water along the contour of the reservoir where vegetation often does not grow. Thus, as water levels rise, floodplains may be the first vegetated habitats inundated within the reservoir. We hypothesized that shallow water in reservoir floodplains would attract spawning white crappies Pomoxis annularis earlier than reservoir embayments. Crappie relative abundance over five years in floodplains and embayments of four reservoirs increased as spawning season approached, peaked, and decreased as fish exited shallow water. Relative abundance peaked earlier in floodplains than embayments, and the difference was magnified with higher water levels. Early access to suitable spawning habitat promotes earlier spawning and may increase population fitness. Recognition of the importance of reservoir floodplains, an understanding of how reservoir water levels can be managed to provide timely connectivity to floodplains, and conservation of reservoir floodplains may be focal points of environmental management in reservoirs.

  3. A Study on Development of a New Algorithm for Predicting the Process Variables in GMA Welding Processes

    NASA Astrophysics Data System (ADS)

    Kim, Ill-Soo; Park, Chang-Eun; Cha, Yong Hoon; Jeong, Young-Jae; Kim, In Kwon; Kim, Jae Yoe; Son, Joon-Sik

    Gas Metal Arc(GMA) welding is extensively employed in the metal industries to weld a variety of ferrous and non-ferrous metals because of its potential for increasing the productivity and quality of welding which is controlled by the process parameters. The objective of this paper is to develop the algorithm that enables the determination of process variables from the optimized bead geometry for robotic GMA welding. It depends on the inversion of empirical equations derived from multiple regression analysis of the relationships between the process variables and the bead dimensions using the least square method. The method directly determines those variables which will give the desired set of bead geometry. This avoids the need to iterate with a succession of guesses employed Finite Element Method(FEM). These results suggest that process variable from experimental equation for robotic GMA welding may be employed to monitor and control the bead geometry in real time.

  4. Development of a computer algorithm for the analysis of variable-frequency AC drives: Case studies included

    NASA Technical Reports Server (NTRS)

    Kankam, M. David; Benjamin, Owen

    1991-01-01

    The development of computer software for performance prediction and analysis of voltage-fed, variable-frequency AC drives for space power applications is discussed. The AC drives discussed include the pulse width modulated inverter (PWMI), a six-step inverter and the pulse density modulated inverter (PDMI), each individually connected to a wound-rotor induction motor. Various d-q transformation models of the induction motor are incorporated for user-selection of the most applicable model for the intended purpose. Simulation results of selected AC drives correlate satisfactorily with published results. Future additions to the algorithm are indicated. These improvements should enhance the applicability of the computer program to the design and analysis of space power systems.

  5. Graph 500 on OpenSHMEM: Using a Practical Survey of Past Work to Motivate Novel Algorithmic Developments

    SciTech Connect

    Grossman, Max; Pritchard Jr., Howard Porter; Budimlic, Zoran; Sarkar, Vivek

    2016-12-22

    Graph500 [14] is an effort to offer a standardized benchmark across large-scale distributed platforms which captures the behavior of common communicationbound graph algorithms. Graph500 differs from other large-scale benchmarking efforts (such as HPL [6] or HPGMG [7]) primarily in the irregularity of its computation and data access patterns. The core computational kernel of Graph500 is a breadth-first search (BFS) implemented on an undirected graph. The output of Graph500 is a spanning tree of the input graph, usually represented by a predecessor mapping for every node in the graph. The Graph500 benchmark defines several pre-defined input sizes for implementers to test against. This report summarizes investigation into implementing the Graph500 benchmark on OpenSHMEM, and focuses on first building a strong and practical understanding of the strengths and limitations of past work before proposing and developing novel extensions.

  6. Development of a Physical Model-Based Algorithm for the Detection of Single-Nucleotide Substitutions by Using Tiling Microarrays

    PubMed Central

    Ono, Naoaki; Suzuki, Shingo; Furusawa, Chikara; Shimizu, Hiroshi; Yomo, Tetsuya

    2013-01-01

    High-density DNA microarrays are useful tools for analyzing sequence changes in DNA samples. Although microarray analysis provides informative signals from a large number of probes, the analysis and interpretation of these signals have certain inherent limitations, namely, complex dependency of signals on the probe sequences and the existence of false signals arising from non-specific binding between probe and target. In this study, we have developed a novel algorithm to detect the single-base substitutions by using microarray data based on a thermodynamic model of hybridization. We modified the thermodynamic model by introducing a penalty for mismatches that represent the effects of substitutions on hybridization affinity. This penalty results in significantly higher detection accuracy than other methods, indicating that the incorporation of hybridization free energy can improve the analysis of sequence variants by using microarray data. PMID:23382915

  7. The development of flux-split algorithms for flows with non-equilibrium thermodynamics and chemical reactions

    NASA Technical Reports Server (NTRS)

    Grossman, B.; Cinella, P.

    1988-01-01

    A finite-volume method for the numerical computation of flows with nonequilibrium thermodynamics and chemistry is presented. A thermodynamic model is described which simplifies the coupling between the chemistry and thermodynamics and also results in the retention of the homogeneity property of the Euler equations (including all the species continuity and vibrational energy conservation equations). Flux-splitting procedures are developed for the fully coupled equations involving fluid dynamics, chemical production and thermodynamic relaxation processes. New forms of flux-vector split and flux-difference split algorithms are embodied in a fully coupled, implicit, large-block structure, including all the species conservation and energy production equations. Several numerical examples are presented, including high-temperature shock tube and nozzle flows. The methodology is compared to other existing techniques, including spectral and central-differenced procedures, and favorable comparisons are shown regarding accuracy, shock-capturing and convergence rates.

  8. Doppler Imaging with a Clean-Like Approach - Part One - a Newly Developed Algorithm Simulations and Tests

    NASA Astrophysics Data System (ADS)

    Kurster, M.

    1993-07-01

    A newly developed method for the Doppler imaging of star spot distributions on active late-type stars is presented. It comprises an algorithm particularly adapted to the (discrete) Doppler imaging problem (including eclipses) and is very efficient in determining the positions and shapes of star spots. A variety of tests demonstrates the capabilities as well as the limitations of the method by investigating the effects that uncertainties in various stellar parameters have on the image reconstruction. Any systematic errors within the reconstructed image are found to be a result of the ill-posed nature of the Doppler imaging problem and not a consequence of the adopted approach. The largest uncertainties are found with respect to the dynamical range of the image (brightness or temperature contrast). This kind of uncertainty is of little effect for studies of star spot migrations with the objectives of determining differential rotation and butterfly diagrams for late-type stars.

  9. Development of real-time diagnostics and feedback algorithms for JET in view of the next step

    NASA Astrophysics Data System (ADS)

    Murari, A.; Joffrin, E.; Felton, R.; Mazon, D.; Zabeo, L.; Albanese, R.; Arena, P.; Ambrosino, G.; Ariola, M.; Barana, O.; Bruno, M.; Laborde, L.; Moreau, D.; Piccolo, F.; Sartori, F.; Crisanti, F.; de la Luna, E.; Sanchez, J.; Contributors, EFDA-JET

    2005-03-01

    Real-time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of next step tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real-time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. Some of the signals now routinely provided in real time at JET are: (i) the internal inductance and the main confinement quantities obtained by calculating the Shafranov integrals from the pick-up coils with 2 ms time resolution; (ii) the electron temperature profile, from electron cylotron emission every 10 ms; (iii) the ion temperature and plasma toroidal velocity profiles, from charge exchange recombination spectroscopy, provided every 50 ms; and (iv) the safety factor profile, derived from the inversion of the polarimetric line integrals every 2 ms. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. With these new tools, several real-time schemes were implemented, among which the most significant is the simultaneous control of the safety factor and the plasma pressure profiles using the additional heating systems (LH, NBI, ICRH) as actuators. The control strategy adopted in this case consists of a multi-variable model-based technique, which was implemented as a truncated singular value decomposition of an integral operator. This approach is considered essential for systems like tokamak machines, characterized by a strong mutual dependence of the various parameters and the distributed nature of the quantities, the plasma profiles, to be controlled. First encouraging results were also obtained using non-algorithmic

  10. Development of a Raman chemical image detection algorithm for authenticating dry milk

    NASA Astrophysics Data System (ADS)

    Qin, Jianwei; Chao, Kuanglin; Kim, Moon S.

    2013-05-01

    This research developed a Raman chemical imaging method for detecting multiple adulterants in skim milk powder. Ammonium sulfate, dicyandiamide, melamine, and urea were mixed into the milk powder as chemical adulterants in the concentration range of 0.1-5.0%. A Raman imaging system using a 785-nm laser acquired hyperspectral images in the wavenumber range of 102-2538 cm-1 for a 25×25 mm2 area of each mixture. A polynomial curve-fitting method was used to correct fluorescence background in the Raman images. An image classification method was developed based on single-band fluorescence-free images at unique Raman peaks of the adulterants. Raman chemical images were created to visualize identification and distribution of the multiple adulterant particles in the milk powder. Linear relationship was found between adulterant pixel number and adulterant concentration, demonstrating the potential of the Raman chemical imaging for quantitative analysis of the adulterants in the milk powder.

  11. Development of an algorithm to model an aircraft equipped with a generic CDTI display

    NASA Technical Reports Server (NTRS)

    Driscoll, W. C.; Houck, J. A.

    1986-01-01

    A model of human pilot performance of a tracking task using a generic Cockpit Display of Traffic Information (CDTI) display is developed from experimental data. The tracking task is to use CDTI in tracking a leading aircraft at a nominal separation of three nautical miles over a prescribed trajectory in space. The analysis of the data resulting from a factorial design of experiments reveals that the tracking task performance depends on the pilot and his experience at performing the task. Performance was not strongly affected by the type of control system used (velocity vector control wheel steering versus 3D automatic flight path guidance and control). The model that is developed and verified results in state trajectories whose difference from the experimental state trajectories is small compared to the variation due to the pilot and experience factors.

  12. Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, and Development

    DTIC Science & Technology

    2003-03-01

    economist named Vilfredo Pareto (1848-1923) first developed the principle of Mul- tiobjective optimization for use in economics. His theories became...Other Approaches to Solving MOPs . . . . . . . . . . . . . . 2-15 2.5 MOP Domain Formalization . . . . . . . . . . . . . . . . . . 2-17 2.5.1 Pareto ...3-33 3.2.4 Relative Coverage Metric . . . . . . . . . . . . . . . 3-33 3.2.5 Maximum Pareto Front Error Metric . . . . . . . . . 3-34

  13. Development of an Outdoor Temperature Based Control Algorithm for Residential Mechanical Ventilation Control

    SciTech Connect

    Less, Brennan; Walker, Iain; Tang, Yihuan

    2014-08-01

    The Incremental Ventilation Energy (IVE) model developed in this study combines the output of simple air exchange models with a limited set of housing characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modellers to use existing databases of housing characteristics to determine the impact of ventilation policy change on a population scale. The IVE model estimates of energy change when applied to US homes with limited parameterisation are shown to be comparable to the estimates of a well-validated, complex residential energy model.

  14. Development of Corrections for Biomass Burning Effects in Version 2 of GEWEX/SRB Algorithm

    NASA Technical Reports Server (NTRS)

    Pinker, Rachel T.; Laszlo, I.; Dicus, Dennis L. (Technical Monitor)

    1999-01-01

    The objectives of this project were: (1) To incorporate into an existing version of the University of Maryland Surface Radiation Budget (SRB) model, optical parameters of forest fire aerosols, using best available information, as well as optical properties of other aerosols, identified as significant. (2) To run the model on regional scales with the new parametrization and information on forest fire occurrence and plume advection, as available from NASA LARC, and test improvements in inferring surface fluxes against daily values of measured fluxes. (3) Develop strategy how to incorporate the new parametrization on global scale and how to transfer modified model to NASA LARC.

  15. Development of signal processing algorithms for ultrasonic detection of coal seam interfaces

    NASA Technical Reports Server (NTRS)

    Purcell, D. D.; Ben-Bassat, M.

    1976-01-01

    A pattern recognition system is presented for determining the thickness of coal remaining on the roof and floor of a coal seam. The system was developed to recognize reflected pulse echo signals that are generated by an acoustical transducer and reflected from the coal seam interface. The flexibility of the system, however, should enable it to identify pulse-echo signals generated by radar or other techniques. The main difference being the specific features extracted from the recorded data as a basis for pattern recognition.

  16. Do emotional support and classroom organization earlier in the year set the stage for higher quality instruction?

    PubMed

    Curby, Timothy W; Rimm-Kaufman, Sara E; Abry, Tashia

    2013-10-01

    Many teachers believe that providing greater emotional and organizational supports in the beginning of the year strengthens their ability to teach effectively as the year progresses. Some interventions, such as the Responsive Classroom (RC) approach, explicitly embed this sequence into professional development efforts. We tested the hypothesis that earlier emotional and organizational supports set the stage for improved instruction later in the year in a sample of third- and fourth-grade teachers enrolled in a randomized controlled trial of the RC approach. Further, we examined the extent to which the model generalized for teachers using varying levels of RC practices as well as whether or not teachers were in the intervention or control groups. Teachers' emotional, organizational, and instructional interactions were observed using the Classroom Assessment Scoring System (Pianta, La Paro, & Hamre, 2008) on five occasions throughout the year. Results indicated a reciprocal relation between emotional and instructional supports. Specifically, higher levels of emotional support earlier in the year predicted higher instructional support later in the year. Also, higher levels of instructional support earlier in the year predicted higher emotional support later in the year. Classroom organization was not found to have longitudinal associations with the other domains across a year. This pattern was robust when controlling for the use of RC practices as well as across intervention and control groups. Further, teachers' use of RC practices predicted higher emotional support and classroom organization throughout the year, suggesting the malleability of this teacher characteristic. Discussion highlights the connection between teachers' emotional and instructional supports and how the use of RC practices improves teachers' emotionally supportive interactions with students.

  17. Development of Subspace-based Hybrid Monte Carlo-Deterministric Algorithms for Reactor Physics Calculations

    SciTech Connect

    Abdel-Khalik, Hany S.; Zhang, Qiong

    2014-05-20

    The development of hybrid Monte-Carlo-Deterministic (MC-DT) approaches, taking place over the past few decades, have primarily focused on shielding and detection applications where the analysis requires a small number of responses, i.e. at the detector locations(s). This work further develops a recently introduced global variance reduction approach, denoted by the SUBSPACE approach is designed to allow the use of MC simulation, currently limited to benchmarking calculations, for routine engineering calculations. By way of demonstration, the SUBSPACE approach is applied to assembly level calculations used to generate the few-group homogenized cross-sections. These models are typically expensive and need to be executed in the order of 103 - 105 times to properly characterize the few-group cross-sections for downstream core-wide calculations. Applicability to k-eigenvalue core-wide models is also demonstrated in this work. Given the favorable results obtained in this work, we believe the applicability of the MC method for reactor analysis calculations could be realized in the near future.

  18. Development of Decision Making Algorithm for Control of Sea Cargo Containers by ``TAGGED'' Neutron Method

    NASA Astrophysics Data System (ADS)

    Anan'ev, A. A.; Belichenko, S. G.; Bogolyubov, E. P.; Bochkarev, O. V.; Petrov, E. V.; Polishchuk, A. M.; Udaltsov, A. Yu.

    2009-12-01

    Nowadays in Russia and abroad there are several groups of scientists, engaged in development of systems based on "tagged" neutron method (API method) and intended for detection of dangerous materials, including high explosives (HE). Particular attention is paid to possibility of detection of dangerous objects inside a sea cargo container. Energy gamma-spectrum, registered from object under inspection is used for determination of oxygen/carbon and nitrogen/carbon chemical ratios, according to which dangerous object is distinguished from not dangerous one. Material of filled container, however, gives rise to additional effects of rescattering and moderation of 14 MeV primary neutrons of generator, attenuation of secondary gamma-radiation from reactions of inelastic neutron scattering on objects under inspection. These effects lead to distortion of energy gamma-response from examined object and therefore prevent correct recognition of chemical ratios. These difficulties are taken into account in analytical method, presented in the paper. Method has been validated against experimental data, obtained by the system for HE detection in sea cargo, based on API method and developed in VNIIA. Influence of shielding materials on results of HE detection and identification is considered. Wood and iron were used as shielding materials. Results of method application for analysis of experimental data on HE simulator measurement (tetryl, trotyl, hexogen) are presented.

  19. DEVELOPMENT OF DECISION MAKING ALGORITHM FOR CONTROL OF SEA CARGO CONTAINERS BY 'TAGGED' NEUTRON METHOD

    SciTech Connect

    Anan'ev, A. A.; Belichenko, S. G.; Bogolyubov, E. P.; Bochkarev, O. V.; Petrov, E. V.; Polishchuk, A. M.; Udaltsov, A. Yu.

    2009-12-02

    Nowadays in Russia and abroad there are several groups of scientists, engaged in development of systems based on 'tagged' neutron method (API method) and intended for detection of dangerous materials, including high explosives (HE). Particular attention is paid to possibility of detection of dangerous objects inside a sea cargo container. Energy gamma-spectrum, registered from object under inspection is used for determination of oxygen/carbon and nitrogen/carbon chemical ratios, according to which dangerous object is distinguished from not dangerous one. Material of filled container, however, gives rise to additional effects of rescattering and moderation of 14 MeV primary neutrons of generator, attenuation of secondary gamma-radiation from reactions of inelastic neutron scattering on objects under inspection. These effects lead to distortion of energy gamma-response from examined object and therefore prevent correct recognition of chemical ratios. These difficulties are taken into account in analytical method, presented in the paper. Method has been validated against experimental data, obtained by the system for HE detection in sea cargo, based on API method and developed in VNIIA. Influence of shielding materials on results of HE detection and identification is considered. Wood and iron were used as shielding materials. Results of method application for analysis of experimental data on HE simulator measurement (tetryl, trotyl, hexogen) are presented.

  20. Development and applications of algorithms for calculating the transonic flow about harmonically oscillating wings

    NASA Technical Reports Server (NTRS)

    Ehlers, F. E.; Weatherill, W. H.; Yip, E. L.

    1984-01-01

    A finite difference method to solve the unsteady transonic flow about harmonically oscillating wings was investigated. The procedure is based on separating the velocity potential into steady and unsteady parts and linearizing the resulting unsteady differential equation for small disturbances. The differential equation for the unsteady velocity potential is linear with spatially varying coefficients and with the time variable eliminated by assuming harmonic motion. An alternating direction implicit procedure was investigated, and a pilot program was developed for both two and three dimensional wings. This program provides a relatively efficient relaxation solution without previously encountered solution instability problems. Pressure distributions for two rectangular wings are calculated. Conjugate gradient techniques were developed for the asymmetric, indefinite problem. The conjugate gradient procedure is evaluated for applications to the unsteady transonic problem. Different equations for the alternating direction procedure are derived using a coordinate transformation for swept and tapered wing planforms. Pressure distributions for swept, untaped wings of vanishing thickness are correlated with linear results for sweep angles up to 45 degrees.

  1. A Crowdsourcing Approach to Developing and Assessing Prediction Algorithms for AML Prognosis.

    PubMed

    Noren, David P; Long, Byron L; Norel, Raquel; Rrhissorrakrai, Kahn; Hess, Kenneth; Hu, Chenyue Wendy; Bisberg, Alex J; Schultz, Andre; Engquist, Erik; Liu, Li; Lin, Xihui; Chen, Gregory M; Xie, Honglei; Hunter, Geoffrey A M; Boutros, Paul C; Stepanov, Oleg; Norman, Thea; Friend, Stephen H; Stolovitzky, Gustavo; Kornblau, Steven; Qutub, Amina A

    2016-06-01

    Acute Myeloid Leukemia (AML) is a fatal hematological cancer. The genetic abnormalities underlying AML are extremely heterogeneous among patients, making prognosis and treatment selection very difficult. While clinical proteomics data has the potential to improve prognosis accuracy, thus far, the quantitative means to do so have yet to be developed. Here we report the results and insights gained from the DREAM 9 Acute Myeloid Prediction Outcome Prediction Challenge (AML-OPC), a crowdsourcing effort designed to promote the development of quantitative methods for AML prognosis prediction. We identify the most accurate and robust models in predicting patient response to therapy, remission duration, and overall survival. We further investigate patient response to therapy, a clinically actionable prediction, and find that patients that are classified as resistant to therapy are harder to predict than responsive patients across the 31 models submitted to the challenge. The top two performing models, which held a high sensitivity to these patients, substantially utilized the proteomics data to make predictions. Using these models, we also identify which signaling proteins were useful in predicting patient therapeutic response.

  2. Development of an Experimental Phased Array Feed System and Algorithms for Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Landon, Jonathan C.

    . Results are given for simulated and experimental data, demonstrating deeper beampattern nulls by 6 to 30dB. To increase the system bandwidth toward the hundreds of MHz bandwidth required by astronomers for a fully science-ready instrument, an FPGA digital backend is introduced using a 64-input analog-to-digital converter running at 50 Msamp/sec and the ROACH processing board developed at the University of California, Berkeley. International efforts to develop digital back ends for large antenna arrays are considered, and a road map is proposed for development of a hardware correlator/beamformer at BYU using three ROACH boards communicating over 10 gigabit Ethernet.

  3. A fuzzy hill-climbing algorithm for the development of a compact associative classifier

    NASA Astrophysics Data System (ADS)

    Mitra, Soumyaroop; Lam, Sarah S.

    2012-02-01

    Classification, a data mining technique, has widespread applications including medical diagnosis, targeted marketing, and others. Knowledge discovery from databases in the form of association rules is one of the important data mining tasks. An integrated approach, classification based on association rules, has drawn the attention of the data mining community over the last decade. While attention has been mainly focused on increasing classifier accuracies, not much efforts have been devoted towards building interpretable and less complex models. This paper discusses the development of a compact associative classification model using a hill-climbing approach and fuzzy sets. The proposed methodology builds the rule-base by selecting rules which contribute towards increasing training accuracy, thus balancing classification accuracy with the number of classification association rules. The results indicated that the proposed associative classification model can achieve competitive accuracies on benchmark datasets with continuous attributes and lend better interpretability, when compared with other rule-based systems.

  4. Issues in the development of a general design algorithm for reliable failure detection

    NASA Technical Reports Server (NTRS)

    Chow, E. Y.; Willsky, A. S.

    1980-01-01

    The design of residual-generation processes is briefly discussed, the goal being to develop a methodology for designing robust processes of this type. It is noted that analytical redundancy forms the basis for residual-generation, representing the relationships between the outputs of sensors and inputs of actuators via the dynamics of the system. It is because of this relationship that sensor outputs (even those of dissimilar sensors and at different times) can, in effect, be compared to ascertain whether they are consistent with normal system behavior. The residuals can be seen as constituting the discrepancy between the output resulting from such comparisons; they should display noise-like characteristics only in the normal mode. Failures in the system would lead to a discrepancy between the observed and expected behavior of the sensor outputs and hence to abnormal characteristics (failure signatures) in the residual.

  5. An approach to the development and analysis of wind turbine control algorithms

    SciTech Connect

    Wu, K.C.

    1998-03-01

    The objective of this project is to develop the capability of symbolically generating an analytical model of a wind turbine for studies of control systems. This report focuses on a theoretical formulation of the symbolic equations of motion (EOMs) modeler for horizontal axis wind turbines. In addition to the power train dynamics, a generic 7-axis rotor assembly is used as the base model from which the EOMs of various turbine configurations can be derived. A systematic approach to generate the EOMs is presented using d`Alembert`s principle and Lagrangian dynamics. A Matlab M file was implemented to generate the EOMs of a two-bladed, free yaw wind turbine. The EOMs will be compared in the future to those of a similar wind turbine modeled with the YawDyn code for verification. This project was sponsored by Sandia National Laboratories as part of the Adaptive Structures and Control Task. This is the final report of Sandia Contract AS-0985.

  6. Development of a Quasi-3D Multiscale Modeling Framework: Motivation, Basic Algorithm and Preliminary results

    NASA Astrophysics Data System (ADS)

    Jung, Joon-Hee; Arakawa, Akio

    2010-04-01

    A new framework for modeling the atmosphere, which we call the quasi-3D (Q3D) multi-scale modeling framework (MMF), is developed with the objective of including cloud-scale three-dimensional effects in a GCM without necessarily using a global cloud-resolving model (CRM). It combines a GCM with a Q3D CRM that has the horizontal domain consisting of two perpendicular sets of channels, each of which contains a locally 3D grid-point array. For computing efficiency, the widths of the channels are chosen to be narrow. Thus, it is crucial to select a proper lateral boundary condition to realistically simulate the statistics of cloud and cloud-associated processes. Among the various possibilities, a periodic lateral boundary condition is chosen for the deviations from background fields that are obtained by interpolations from the GCM grid points. Since the deviations tend to vanish as the GCM grid size approaches that of the CRM, the whole system of the Q3D MMF can converge to a fully 3D global CRM. Consequently, the horizontal resolution of the GCM can be freely chosen depending on the objective of application, without changing the formulation of model physics. To evaluate the newly developed Q3D CRM in an efficient way, idealized experiments have been performed using a small horizontal domain. In these tests, the Q3D CRM uses only one pair of perpendicular channels with only two grid points across each channel. Comparing the simulation results with those of a fully 3D CRM, it is concluded that the Q3D CRM can reproduce most of the important statistics of the 3D solutions, including the vertical distributions of cloud water and precipitants, vertical transports of potential temperature and water vapor, and the variances and covariances of dynamical variables. The main improvement from a corresponding 2D simulation appears in the surface fluxes and the vorticity transports that cause the mean wind to change. A comparison with a simulation using a coarse-resolution 3D CRM

  7. Neural network and fuzzy logic based secondary cells charging algorithm development and the controller architecture for implementation

    NASA Astrophysics Data System (ADS)

    Ullah, Muhammed Zafar

    Neural Network and Fuzzy Logic are the two key technologies that have recently received growing attention in solving real world, nonlinear, time variant problems. Because of their learning and/or reasoning capabilities, these techniques do not need a mathematical model of the system, which may be difficult, if not impossible, to obtain for complex systems. One of the major problems in portable or electric vehicle world is secondary cell charging, which shows non-linear characteristics. Portable-electronic equipment, such as notebook computers, cordless and cellular telephones and cordless-electric lawn tools use batteries in increasing numbers. These consumers demand fast charging times, increased battery lifetime and fuel gauge capabilities. All of these demands require that the state-of-charge within a battery be known. Charging secondary cells Fast is a problem, which is difficult to solve using conventional techniques. Charge control is important in fast charging, preventing overcharging and improving battery life. This research work provides a quick and reliable approach to charger design using Neural-Fuzzy technology, which learns the exact battery charging characteristics. Neural-Fuzzy technology is an intelligent combination of neural net with fuzzy logic that learns system behavior by using system input-output data rather than mathematical modeling. The primary objective of this research is to improve the secondary cell charging algorithm and to have faster charging time based on neural network and fuzzy logic technique. Also a new architecture of a controller will be developed for implementing the charging algorithm for the secondary battery.

  8. Development of an algorithm for the analysis of surface defects in mechanical elements

    NASA Astrophysics Data System (ADS)

    Fargione, Giovanna A.; Geraci, Alberto L.; Pennisi, Luigi; Risitano, Antonino

    1998-10-01

    The non-destructive tests allow to establish the physical and structural conditions of a mechanical part, to verify its condition, the superficial wear and tear and then evaluate its `remaining' efficiency. The non-destructive tests are applied in all those fields of engineering in which the determination of the mechanical and structural characteristics of elements in use is requested, without making them undergo destructive or damaging tests. In the present work an application program has been developed which, examining the surface of mechanical parts under an optical microscope and a blaster video, is able to characterize the material and to recognize and identify the possible presence of a superficial crack. The program constitutes the first step towards the realization of an industrial prototype which, thanks to the utilization of a plan moved by step-by-step motors, allowing the scanning of the whole surface of a part and the recognition of the crack in an automatic way, that is without the presence of an operator, and its characterization, in case it is identified, through the determination of some geometric parameters useful to ascertain the structural integrity of the element under examination. For the realization of the program different techniques of image analysis have been applied and the use of an artificial neural network preset for the recognition of the crack has been necessary. The program has been realized in C language and it works in Linux system.

  9. Utilization of MCNP for the development of spectral stripping algorithms for orthovoltage radiation therapy systems

    NASA Astrophysics Data System (ADS)

    Brown, Steven; Detwiler, Rebecca S.; Lu, Bo; Gopal, Arun; Samant, Sangiv; Baciak, James E.

    2011-10-01

    We are developing a Monte-Carlo based method for spectral stripping of a low-voltage X-ray detector spectrum for calibrating and performing quality assurance with orthovoltage (X-ray) radiation therapy systems. The technique involves a tungsten-based X-ray generator with limited energy spectral information of at the most two half value layers of shielding available from the manufacturer. The goal is to generate a complete energy spectrum of the source from a measured detector spectrum, by correcting for radiation losses and misplaced counts due to Compton scattering and the photoelectric effect. In this work, energy spectra were measured at generator voltages of 150-300 kVp with HPGe and Si detectors, with several optional shielding configurations. The source to detector geometry were modeled in MCNP, and the reaction rates and spatial locations of Compton scattering and photoelectric events in the detectors have been investigated as a function of source energy to gain information on where interactions occur for the given beam collimation and geometry. Photon leakage and energy flux out of the detector were also simulated, and initial spectral stripping has been performed on the HPGe and Si detector spectra.

  10. Assessing hemlock decline using visible and near-infrared spectroscopy: indices comparison and algorithm development.

    PubMed

    Pontius, Jennifer; Hallett, Richard; Martin, Mary

    2005-06-01

    Near-infrared reflectance spectroscopy was evaluated for its effectiveness at predicting pre-visual decline in eastern hemlock trees. An ASD FieldSpec Pro FR field spectroradiometer measuring 2100 contiguous 1-nm-wide channels from 350 nm to 2500 nm was used to collect spectra from fresh hemlock foliage. Full spectrum partial least squares (PLS) regression equations and reduced stepwise linear regression equations were compared. The best decline predictive model was a 6-term linear regression equation (R2= 0.71, RMSE = 0.591) based on: Carter Miller Stress Index (R694/R760), Derivative Chlorophyll Index (FD705/FD723), Normalized Difference Vegetation Index ((R800 - R680)/(R800 + R680)), R950, R1922, and FD1388. Accuracy assessment showed that this equation predicted an 11-class decline rating with a 1-class tolerance accuracy of 96% and differentiated healthy trees from those in very early decline with 72% accuracy. These results indicate that narrow-band sensors could be developed to detect very early stages of hemlock decline, before visual symptoms are apparent. This capability would enable land managers to identify early hemlock woolly adelgid infestations and monitor forest health over large areas of the landscape.

  11. Developing an algorithm for enhancement of a digital terrain model for a densely vegetated floodplain wetland

    NASA Astrophysics Data System (ADS)

    Mirosław-Świątek, Dorota; Szporak-Wasilewska, Sylwia; Michałowski, Robert; Kardel, Ignacy; Grygoruk, Mateusz

    2016-07-01

    Airborne laser scanning survey data were conducted with a scanning density of 4 points/m2 to accurately map the surface of a unique central European complex of wetlands: the lower Biebrza River valley (Poland). A method to correct a degrading effect of vegetation (so-called "vegetation effect") on digital terrain models (DTMs) was applied utilizing remotely sensed images, real-time kinematic global positioning system elevation measurements, topographical surveys, and vegetation height measurements. Geographic object-based image analysis (GEOBIA) was performed to map vegetation within the study area that was used as categories from which vegetation height information was derived for the DTM correction. The final DTM was compared with a model obtained, where additional correction of the "vegetation effect" was neglected. A comparison between corrected and uncorrected DTMs demonstrated the importance of accurate topography through a simple presentation of the discrepancies arising in features of the flood using various DTM products. An overall map classification accuracy of 80% was attained with the use of GEOBIA. Correction factors developed for various types of the vegetation reached values from 0.08 up to 0.92 m and were dependent on the vegetation type.

  12. Runway Exit Designs for Capacity Improvement Demonstrations. Phase 1: Algorithm Development

    NASA Technical Reports Server (NTRS)

    Trani, A. A.; Hobeika, A. G.; Sherali, H.; Kim, B. J.; Sadam, C. K.

    1990-01-01

    A description and results are presented of a study to locate and design rapid runway exits under realistic airport conditions. The study developed a PC-based computer simulation-optimization program called REDIM (runway exit design interactive model) to help future airport designers and planners to locate optimal exits under various airport conditions. The model addresses three sets of problems typically arising during runway exit design evaluations. These are the evaluations of existing runway configurations, addition of new rapid runway turnoffs, and the design of new runway facilities. The model is highly interactive and allows