Analytical drafting curves provide exact equations for plotted data

NASA Technical Reports Server (NTRS)

Stewart, R. B.

1967-01-01

Analytical drafting curves provide explicit mathematical expressions for any numerical data that appears in the form of graphical plots. The curves each have a reference coordinate axis system indicated on the curve as well as the mathematical equation from which the curve was generated.

AstroImageJ: Image Processing and Photometric Extraction for Ultra-precise Astronomical Light Curves

NASA Astrophysics Data System (ADS)

Collins, Karen A.; Kielkopf, John F.; Stassun, Keivan G.; Hessman, Frederic V.

2017-02-01

ImageJ is a graphical user interface (GUI) driven, public domain, Java-based, software package for general image processing traditionally used mainly in life sciences fields. The image processing capabilities of ImageJ are useful and extendable to other scientific fields. Here we present AstroImageJ (AIJ), which provides an astronomy specific image display environment and tools for astronomy specific image calibration and data reduction. Although AIJ maintains the general purpose image processing capabilities of ImageJ, AIJ is streamlined for time-series differential photometry, light curve detrending and fitting, and light curve plotting, especially for applications requiring ultra-precise light curves (e.g., exoplanet transits). AIJ reads and writes standard Flexible Image Transport System (FITS) files, as well as other common image formats, provides FITS header viewing and editing, and is World Coordinate System aware, including an automated interface to the astrometry.net web portal for plate solving images. AIJ provides research grade image calibration and analysis tools with a GUI driven approach, and easily installed cross-platform compatibility. It enables new users, even at the level of undergraduate student, high school student, or amateur astronomer, to quickly start processing, modeling, and plotting astronomical image data with one tightly integrated software package.

NASADIG - NASA DEVICE INDEPENDENT GRAPHICS LIBRARY (AMDAHL VERSION)

NASA Technical Reports Server (NTRS)

Rogers, J. E.

1994-01-01

The NASA Device Independent Graphics Library, NASADIG, can be used with many computer-based engineering and management applications. The library gives the user the opportunity to translate data into effective graphic displays for presentation. The software offers many features which allow the user flexibility in creating graphics. These include two-dimensional plots, subplot projections in 3D-space, surface contour line plots, and surface contour color-shaded plots. Routines for three-dimensional plotting, wireframe surface plots, surface plots with hidden line removal, and surface contour line plots are provided. Other features include polar and spherical coordinate plotting, world map plotting utilizing either cylindrical equidistant or Lambert equal area projection, plot translation, plot rotation, plot blowup, splines and polynomial interpolation, area blanking control, multiple log/linear axes, legends and text control, curve thickness control, and multiple text fonts (18 regular, 4 bold). NASADIG contains several groups of subroutines. Included are subroutines for plot area and axis definition; text set-up and display; area blanking; line style set-up, interpolation, and plotting; color shading and pattern control; legend, text block, and character control; device initialization; mixed alphabets setting; and other useful functions. The usefulness of many routines is dependent on the prior definition of basic parameters. The program's control structure uses a serial-level construct with each routine restricted for activation at some prescribed level(s) of problem definition. NASADIG provides the following output device drivers: Selanar 100XL, VECTOR Move/Draw ASCII and PostScript files, Tektronix 40xx, 41xx, and 4510 Rasterizer, DEC VT-240 (4014 mode), IBM AT/PC compatible with SmartTerm 240 emulator, HP Lasergrafix Film Recorder, QMS 800/1200, DEC LN03+ Laserprinters, and HP LaserJet (Series III). NASADIG is written in FORTRAN and is available for several platforms. NASADIG 5.7 is available for DEC VAX series computers running VMS 5.0 or later (MSC-21801), Cray X-MP and Y-MP series computers running UNICOS (COS-10049), and Amdahl 5990 mainframe computers running UTS (COS-10050). NASADIG 5.1 is available for UNIX-based operating systems (MSC-22001). The UNIX version has been successfully implemented on Sun4 series computers running SunOS, SGI IRIS computers running IRIX, Hewlett Packard 9000 computers running HP-UX, and Convex computers running Convex OS (MSC-22001). The standard distribution medium for MSC-21801 is a set of two 6250 BPI 9-track magnetic tapes in DEC VAX BACKUP format. It is also available on a set of two TK50 tape cartridges in DEC VAX BACKUP format. The standard distribution medium for COS-10049 and COS-10050 is a 6250 BPI 9-track magnetic tape in UNIX tar format. Other distribution media and formats may be available upon request. The standard distribution medium for MSC-22001 is a .25 inch streaming magnetic tape cartridge (Sun QIC-24) in UNIX tar format. Alternate distribution media and formats are available upon request. With minor modification, the UNIX source code can be ported to other platforms including IBM PC/AT series computers and compatibles. NASADIG is also available bundled with TRASYS, the Thermal Radiation Analysis System (COS-10026, DEC VAX version; COS-10040, CRAY version).

NASADIG - NASA DEVICE INDEPENDENT GRAPHICS LIBRARY (UNIX VERSION)

NASA Technical Reports Server (NTRS)

Rogers, J. E.

1994-01-01

The NASA Device Independent Graphics Library, NASADIG, can be used with many computer-based engineering and management applications. The library gives the user the opportunity to translate data into effective graphic displays for presentation. The software offers many features which allow the user flexibility in creating graphics. These include two-dimensional plots, subplot projections in 3D-space, surface contour line plots, and surface contour color-shaded plots. Routines for three-dimensional plotting, wireframe surface plots, surface plots with hidden line removal, and surface contour line plots are provided. Other features include polar and spherical coordinate plotting, world map plotting utilizing either cylindrical equidistant or Lambert equal area projection, plot translation, plot rotation, plot blowup, splines and polynomial interpolation, area blanking control, multiple log/linear axes, legends and text control, curve thickness control, and multiple text fonts (18 regular, 4 bold). NASADIG contains several groups of subroutines. Included are subroutines for plot area and axis definition; text set-up and display; area blanking; line style set-up, interpolation, and plotting; color shading and pattern control; legend, text block, and character control; device initialization; mixed alphabets setting; and other useful functions. The usefulness of many routines is dependent on the prior definition of basic parameters. The program's control structure uses a serial-level construct with each routine restricted for activation at some prescribed level(s) of problem definition. NASADIG provides the following output device drivers: Selanar 100XL, VECTOR Move/Draw ASCII and PostScript files, Tektronix 40xx, 41xx, and 4510 Rasterizer, DEC VT-240 (4014 mode), IBM AT/PC compatible with SmartTerm 240 emulator, HP Lasergrafix Film Recorder, QMS 800/1200, DEC LN03+ Laserprinters, and HP LaserJet (Series III). NASADIG is written in FORTRAN and is available for several platforms. NASADIG 5.7 is available for DEC VAX series computers running VMS 5.0 or later (MSC-21801), Cray X-MP and Y-MP series computers running UNICOS (COS-10049), and Amdahl 5990 mainframe computers running UTS (COS-10050). NASADIG 5.1 is available for UNIX-based operating systems (MSC-22001). The UNIX version has been successfully implemented on Sun4 series computers running SunOS, SGI IRIS computers running IRIX, Hewlett Packard 9000 computers running HP-UX, and Convex computers running Convex OS (MSC-22001). The standard distribution medium for MSC-21801 is a set of two 6250 BPI 9-track magnetic tapes in DEC VAX BACKUP format. It is also available on a set of two TK50 tape cartridges in DEC VAX BACKUP format. The standard distribution medium for COS-10049 and COS-10050 is a 6250 BPI 9-track magnetic tape in UNIX tar format. Other distribution media and formats may be available upon request. The standard distribution medium for MSC-22001 is a .25 inch streaming magnetic tape cartridge (Sun QIC-24) in UNIX tar format. Alternate distribution media and formats are available upon request. With minor modification, the UNIX source code can be ported to other platforms including IBM PC/AT series computers and compatibles. NASADIG is also available bundled with TRASYS, the Thermal Radiation Analysis System (COS-10026, DEC VAX version; COS-10040, CRAY version).

Experimental determination of the yield stress curve of the scotch pine wood materials

NASA Astrophysics Data System (ADS)

Günay, Ezgi; Aygün, Cevdet; Kaya, Şükrü Tayfun

2013-12-01

Yield stress curve is determined for the pine wood specimens by conducting a series of tests. In this work, pinewood is modeled as a composite material with transversely isotropic fibers. Annual rings (wood grain) of the wood specimens are taken as the major fiber directions with which the strain gauge directions are aligned. For this purpose, three types of tests are arranged. These are tensile, compression and torsion loading tests. All of the tests are categorized with respect to fiber orientations and their corresponding loading conditions. Each test within these categories is conducted separately. Tensile and compression tests are conducted in accordance with standards of Turkish Standards Institution (TSE) whereas torsion tests are conducted in accordance with Standards Australia. Specimens are machined from woods of Scotch pine which is widely used in boat building industries and in other structural engineering applications. It is determined that this species behaves more flexibly than the others. Strain gauges are installed on the specimen surfaces in such a way that loading measurements are performed along directions either parallel or perpendicular to the fiber directions. During the test and analysis phase of yield stress curve, orientation of strain gauge directions with respect to fiber directions are taken into account. The diagrams of the normal stress vs. normal strain or the shear stress vs. shear strain are plotted for each test. In each plot, the yield stress is determined by selecting the point on the diagram, the tangent of which is having a slope of 5% less than the slope of the elastic portion of the diagram. The geometric locus of these selected points constitutes a single yield stress curve on σ1-σ2 principal plane. The resulting yield stress curve is plotted as an approximate ellipse which resembles Tsai-Hill failure criterion. The results attained in this work, compare well with the results which are readily available in the literature.

Relative rates for plasma homo- and copolymerizations of olefins in a homologous series of fluorinated ethylenes

NASA Technical Reports Server (NTRS)

Golub, M. A.; Wydeven, T.

1997-01-01

It is well known that the rate of plasma polymerization, or deposition rate, of a given monomer depends on various plasma process parameters, e.g., monomer flow rate, pressure, power, frequency (DC, rf or microwave), location of the substrate in the reactor, reactor geometry or configuration, and temperature. In contrast, little work has been done to relate deposition rates to monomer structures for a homologous series of monomers where the rates are obtained under identical plasma process parameters. For the particular series of fluorinated ethylenes (C2HxF4-x; x = 0-4), deposition rates were reported for ethylene (ET), vinyl fluoride, vinylidene fluoride and tetrafluoroethylene (TFE), but for plasma polymerizations carried out under different discharge conditions, e.g., pressure, current density, and electrode temperature. Apparently, relative deposition rates were reported for only two members of that series (ET, x = 4, and TFE, x = 0) for which the plasma polymerizations were conducted under identical conditions. We now present relative deposition rates for both homopolymerizations and copolymerizations of the entire series of fluorinated ethylenes (x = 0-4). Our interest in such rates stems from prior work on the plasma copolymerization of ET and TFE in which it was found that the deposition rates for the plasma copolymers, when plotted versus mol % TFE in the ET/TFE feed stock, followed a concave-downward curve situated above the straight line joining the deposition rates for the plasma homopolymers. This type of plot (observed also for an argon-ET/TFE plasma copolymerization) indicated a positive interaction between ET and TFE such that each monomer apparently "sensitized" the plasma copolymerization of the other. Since the shape of that plot is not altered if mol % TFE is replaced by F/C, the fluorine-to-carbon ratio, this paper aims (1) to show how the relative deposition rates for plasma copolymers drawn from all pairs of monomers in the C2HxF4-x series, as well as the deposition rates for the individual plasma homopolymers, vary with F/C ratios of the monomers or monomer blends, and (2) to see if those rates give rise to a common plot.

Tracing Personalized Health Curves during Infections

PubMed Central

Schneider, David S.

2011-01-01

It is difficult to describe host–microbe interactions in a manner that deals well with both pathogens and mutualists. Perhaps a way can be found using an ecological definition of tolerance, where tolerance is defined as the dose response curve of health versus parasite load. To plot tolerance, individual infections are summarized by reporting the maximum parasite load and the minimum health for a population of infected individuals and the slope of the resulting curve defines the tolerance of the population. We can borrow this method of plotting health versus microbe load in a population and make it apply to individuals; instead of plotting just one point that summarizes an infection in an individual, we can plot the values at many time points over the course of an infection for one individual. This produces curves that trace the course of an infection through phase space rather than over a more typical timeline. These curves highlight relationships like recovery and point out bifurcations that are difficult to visualize with standard plotting techniques. Only nine archetypical curves are needed to describe most pathogenic and mutualistic host–microbe interactions. The technique holds promise as both a qualitative and quantitative approach to dissect host–microbe interactions of all kinds. PMID:21957398

WORM - WINDOWED OBSERVATION OF RELATIVE MOTION

NASA Technical Reports Server (NTRS)

Bauer, F.

1994-01-01

The Windowed Observation of Relative Motion, WORM, program is primarily intended for the generation of simple X-Y plots from data created by other programs. It allows the user to label, zoom, and change the scale of various plots. Three dimensional contour and line plots are provided, although with more limited capabilities. The input data can be in binary or ASCII format, although all data must be in the same format. A great deal of control over the details of the plot is provided, such as gridding, size of tick marks, colors, log/semilog capability, time tagging, and multiple and phase plane plots. Many color and monochrome graphics terminals and hard copy printer/plotters are supported. The WORM executive commands, menu selections and macro files can be used to develop plots and tabular data, query the WORM Help library, retrieve data from input files, and invoke VAX DCL commands. WORM generated plots are displayed on local graphics terminals and can be copied using standard hard copy capabilities. Some of the graphics features of WORM include: zooming and dezooming various portions of the plot; plot documentation including curve labeling and function listing; multiple curves on the same plot; windowing of multiple plots and insets of the same plot; displaying a specific on a curve; and spinning the curve left, right, up, and down. WORM is written in PASCAL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.7 with a virtual memory requirement of approximately 392K of 8 bit bytes. It uses the QPLOT device independent graphics library included with WORM. It was developed in 1988.

A geometric morphometric study into the sexual dimorphism of the human scapula.

PubMed

Scholtz, Y; Steyn, M; Pretorius, E

2010-08-01

Sex determination is vital when attempting to establish identity from skeletal remains. Two approaches to sex determination exists: morphological and metrical. The aim of this paper was to use geometric morphometrics to study the shape of the scapula and its sexual dimorphism. The sample comprised 45 adult black male and 45 adult black female scapulae of known sex. The scapulae were photographed and 21 homologous landmarks were plotted to use for geometric morphometric analysis with the 'tps' series of programs, as well as the IMP package. Consensus thin-plate splines and vector plots for males and females were compared. The CVA and TwoGroup analyses indicated that significant differences exist between males and females. The lateral and medial borders of females are straighter while the supraspinous fossa is more convexly curved than that of males. More than 91% of the females and 95% of the males were correctly assigned. Hotelling's T(2)-test yielded a significant p-value of 0.00039. In addition, 100 equidistant landmarks representing the curve only were also assigned. These, however, yielded considerably poorer results. It is concluded that it is better to use homologous landmarks rather than curve data only, as it is most probable that the shape of the outline relative to the fixed homologous points on the scapula is sexually dimorphic.

46 CFR 170.090 - Calculations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... necessary to compute and plot any of the following curves as part of the calculations required in this subchapter, these plots must also be submitted: (1) Righting arm or moment curves. (2) Heeling arm or moment...

Graphical Data Analysis on the Circle: Wrap-Around Time Series Plots for (Interrupted) Time Series Designs.

PubMed

Rodgers, Joseph Lee; Beasley, William Howard; Schuelke, Matthew

2014-01-01

Many data structures, particularly time series data, are naturally seasonal, cyclical, or otherwise circular. Past graphical methods for time series have focused on linear plots. In this article, we move graphical analysis onto the circle. We focus on 2 particular methods, one old and one new. Rose diagrams are circular histograms and can be produced in several different forms using the RRose software system. In addition, we propose, develop, illustrate, and provide software support for a new circular graphical method, called Wrap-Around Time Series Plots (WATS Plots), which is a graphical method useful to support time series analyses in general but in particular in relation to interrupted time series designs. We illustrate the use of WATS Plots with an interrupted time series design evaluating the effect of the Oklahoma City bombing on birthrates in Oklahoma County during the 10 years surrounding the bombing of the Murrah Building in Oklahoma City. We compare WATS Plots with linear time series representations and overlay them with smoothing and error bands. Each method is shown to have advantages in relation to the other; in our example, the WATS Plots more clearly show the existence and effect size of the fertility differential.

Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007

USGS Publications Warehouse

Asquith, William H.; Heitmuller, Franklin T.

2008-01-01

Analysts and managers of surface-water resources have interest in annual mean and annual harmonic mean statistics of daily mean streamflow for U.S. Geological Survey (USGS) streamflow-gaging stations in Texas. The mean streamflow represents streamflow volume, whereas the harmonic mean streamflow represents an appropriate statistic for assessing constituent concentrations that might adversely affect human health. In 2008, the USGS, in cooperation with the Texas Commission on Environmental Quality, conducted a large-scale documentation of mean and harmonic mean streamflow for 620 active and inactive, continuous-record, streamflow-gaging stations using period of record data through water year 2007. About 99 stations within the Texas USGS streamflow-gaging network are part of the larger national Hydroclimatic Data Network and are identified. The graphical depictions of annual mean and annual harmonic mean statistics in this report provide a historical perspective of streamflow at each station. Each figure consists of three time-series plots, two flow-duration curves, and a statistical summary of the mean annual and annual harmonic mean streamflow statistics for available data for each station.The first time-series plot depicts daily mean streamflow for the period 1900-2007. Flow-duration curves follow and are a graphical depiction of streamflow variability. Next, the remaining two time-series plots depict annual mean and annual harmonic mean streamflow and are augmented with horizontal lines that depict mean and harmonic mean for the period of record. Monotonic trends for the annual mean streamflow and annual harmonic mean streamflow also are identified using Kendall's tau, and the slope of the trend is depicted using the nonparametric (linear) Theil-Sen line, which is only drawn for p-values less than .10 of tau. The history of annual mean and annual harmonic mean streamflow of one or more streamflow-gaging stations could be used in a watershed, river basin, or other regional context by analysts and managers of surface-water resources to guide scientific, regulatory, or other inquiries of streamflow conditions in Texas.

Identifying Changes of Complex Flood Dynamics with Recurrence Analysis

NASA Astrophysics Data System (ADS)

Wendi, D.; Merz, B.; Marwan, N.

2016-12-01

Temporal changes in flood hazard system are known to be difficult to detect and attribute due to multiple drivers that include complex processes that are non-stationary and highly variable. These drivers, such as human-induced climate change, natural climate variability, implementation of flood defense, river training, or land use change, could impact variably on space-time scales and influence or mask each other. Flood time series may show complex behavior that vary at a range of time scales and may cluster in time. Moreover hydrological time series (i.e. discharge) are often subject to measurement errors, such as rating curve error especially in the case of extremes where observation are actually derived through extrapolation. This study focuses on the application of recurrence based data analysis techniques (recurrence plot) for understanding and quantifying spatio-temporal changes in flood hazard in Germany. The recurrence plot is known as an effective tool to visualize the dynamics of phase space trajectories i.e. constructed from a time series by using an embedding dimension and a time delay, and it is known to be effective in analyzing non-stationary and non-linear time series. Sensitivity of the common measurement errors and noise on recurrence analysis will also be analyzed and evaluated against conventional methods. The emphasis will be on the identification of characteristic recurrence properties that could associate typical dynamic to certain flood events.

Characterization of chaotic attractors under noise: A recurrence network perspective

NASA Astrophysics Data System (ADS)

Jacob, Rinku; Harikrishnan, K. P.; Misra, R.; Ambika, G.

2016-12-01

We undertake a detailed numerical investigation to understand how the addition of white and colored noise to a chaotic time series changes the topology and the structure of the underlying attractor reconstructed from the time series. We use the methods and measures of recurrence plot and recurrence network generated from the time series for this analysis. We explicitly show that the addition of noise obscures the property of recurrence of trajectory points in the phase space which is the hallmark of every dynamical system. However, the structure of the attractor is found to be robust even upto high noise levels of 50%. An advantage of recurrence network measures over the conventional nonlinear measures is that they can be applied on short and non stationary time series data. By using the results obtained from the above analysis, we go on to analyse the light curves from a dominant black hole system and show that the recurrence network measures are capable of identifying the nature of noise contamination in a time series.

Piecewise-homotopy analysis method (P-HAM) for first order nonlinear ODE

NASA Astrophysics Data System (ADS)

Chin, F. Y.; Lem, K. H.; Chong, F. S.

2013-09-01

In homotopy analysis method (HAM), the determination for the value of the auxiliary parameter h is based on the valid region of the h-curve in which the horizontal segment of the h-curve will decide the valid h-region. All h-value taken from the valid region, provided that the order of deformation is large enough, will in principle yield an approximation series that converges to the exact solution. However it is found out that the h-value chosen within this valid region does not always promise a good approximation under finite order. This paper suggests an improved method called Piecewise-HAM (P-HAM). In stead of a single h-value, this method suggests using many h-values. Each of the h-values comes from an individual h-curve while each h-curve is plotted by fixing the time t at a different value. Each h-value is claimed to produce a good approximation only about a neighborhood centered at the corresponding t which the h-curve is based on. Each segment of these good approximations is then joined to form the approximation curve. By this, the convergence region is enhanced further. The P-HAM is illustrated and supported by examples.

Multiscale Poincaré plots for visualizing the structure of heartbeat time series.

PubMed

Henriques, Teresa S; Mariani, Sara; Burykin, Anton; Rodrigues, Filipa; Silva, Tiago F; Goldberger, Ary L

2016-02-09

Poincaré delay maps are widely used in the analysis of cardiac interbeat interval (RR) dynamics. To facilitate visualization of the structure of these time series, we introduce multiscale Poincaré (MSP) plots. Starting with the original RR time series, the method employs a coarse-graining procedure to create a family of time series, each of which represents the system's dynamics in a different time scale. Next, the Poincaré plots are constructed for the original and the coarse-grained time series. Finally, as an optional adjunct, color can be added to each point to represent its normalized frequency. We illustrate the MSP method on simulated Gaussian white and 1/f noise time series. The MSP plots of 1/f noise time series reveal relative conservation of the phase space area over multiple time scales, while those of white noise show a marked reduction in area. We also show how MSP plots can be used to illustrate the loss of complexity when heartbeat time series from healthy subjects are compared with those from patients with chronic (congestive) heart failure syndrome or with atrial fibrillation. This generalized multiscale approach to Poincaré plots may be useful in visualizing other types of time series.

Kinetics of suicide substrates. Practical procedures for determining parameters.

PubMed Central

Waley, S G

1985-01-01

Many clinically important or mechanistically interesting inhibitors react with enzymes by a branched pathway in which inactivation of the enzyme and formation of product are competing reactions. The steady-state kinetics for this pathway [Waley (1980) Biochem. J. 185, 771-773] gave equations for progress curves that were cumbersome. A convenient linear plot is now described. The time (t1/2) for 50% inactivation of the enzyme (this is also the time for 50% formation of product), or for 50% loss of substrate, is measured in a series of experiments in which the concentration of inhibitor, [I]0, is varied; in these experiments the ratio of the concentration of enzyme to the concentration of inhibitor is kept fixed. Then a plot of [I]0 X t1/2 against [I]0 is linear, and the kinetic parameters can be found from the slope and intercept. Furthermore, simplifications of the equations for progress curves are described that are valid when the concentration of inhibitors is high, or is low, or when the extent of reaction is low. The use of simulated data has shown that the recommended methods are not unduly sensitive to experimental error. PMID:4004802

MHD Convective Flow of Jeffrey Fluid Due to a Curved Stretching Surface with Homogeneous-Heterogeneous Reactions

PubMed Central

Imtiaz, Maria; Hayat, Tasawar; Alsaedi, Ahmed

2016-01-01

This paper looks at the flow of Jeffrey fluid due to a curved stretching sheet. Effect of homogeneous-heterogeneous reactions is considered. An electrically conducting fluid in the presence of applied magnetic field is considered. Convective boundary conditions model the heat transfer analysis. Transformation method reduces the governing nonlinear partial differential equations into the ordinary differential equations. Convergence of the obtained series solutions is explicitly discussed. Characteristics of sundry parameters on the velocity, temperature and concentration profiles are analyzed by plotting graphs. Computations for pressure, skin friction coefficient and surface heat transfer rate are presented and examined. It is noted that fluid velocity and temperature through curvature parameter are enhanced. Increasing values of Biot number correspond to the enhancement in temperature and Nusselt number. PMID:27583457

Enhanced Night Vision Via a Combination of Poisson Interpolation and Machine Learning

DTIC Science & Technology

2006-02-01

of 0-255, they are mostly similar. The right plot shows a family of m(x, ψ) curves of ψ=2 (the most linear) through ψ=1024 (the most curved ...complicating low-light imaging. Nayar and Branzoi [04] later suggested a second variant using a DLP micromirror array to modulate the exposure, via time...255, they are mostly similar. The right plot shows a family of m(x, ψ) curves of ψ=2 (the most linear) through ψ=1024 (the most curved

Effects of Bacillus thuringiensis on non-target herbivore and natural enemy assemblages in tropical irrigated rice.

PubMed

Schoenly, Kenneth G; Cohen, Michael B; Barrion, Alberto T; Zhang, Wenjun; Gaolach, Bradley; Viajante, Vicente D

2003-01-01

Endotoxins from Bacillus thuringiensis (Bt) produced in transgenic pest-resistant Bt crops are generally not toxic to predatory and parasitic arthropods. However, elimination of Bt-susceptible prey and hosts in Bt crops could reduce predator and parasitoid abundance and thereby disrupt biological control of other herbivorous pests. Here we report results of a field study evaluating the effects of Bt sprays on non-target terrestrial herbivore and natural enemy assemblages from three rice (Oryza sativa L.) fields on Luzon Island, Philippines. Because of restrictions on field-testing of transgenic rice, Bt sprays were used to remove foliage-feeding lepidopteran larvae that would be targeted by Bt rice. Data from a 546-taxa Philippines-wide food web, matched abundance plots, species accumulation curves, time-series analysis, and ecostatistical tests for species richness and ranked abundance were used to compare different subsets of non-target herbivores, predators, and parasitoids in Bt sprayed and water-sprayed (control) plots. For whole communities of terrestrial predators and parasitoids, Bt sprays altered parasitoid richness in 3 of 3 sites and predator richness in 1 of 3 sites, as measured by rarefaction (in half of these cases, richness was greater in Bt plots), while Spearman tests on ranked abundances showed that correlations, although significantly positive between all treatment pairs, were stronger for predators than for parasitoids, suggesting that parasitoid complexes may have been more sensitive than predators to the effects of Bt sprays. Species accumulation curves and time-series analyses of population trends revealed no evidence that Bt sprays altered the overall buildup of predator or parasitoid communities or population trajectories of non-target herbivores (planthoppers and leafhoppers) nor was evidence found for bottom-up effects in total abundances of non-target species identified in the food web from the addition of spores in the Bt spray formulation. When the same methods were applied to natural enemies (predators and parasitoids) of foliage-feeding lepidopteran and non-lepidopteran (homopteran, hemipteran and dipteran) herbivores, significant differences between treatments were detected in 7 of 12 cases. However, no treatment differences were found in mean abundances of these natural enemies, either in time-series plots or in total (seasonal) abundance. Analysis of guild-level trajectories revealed population behavior and treatment differences that could not be predicted in whole-community studies of predators and parasitoids. A more conclusive test of the impact of Bt rice will require field experiments with transgenic plants, conducted in a range of Asian environments, and over multiple cropping seasons.

Understand Centrifugal Compressor stage curves

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

Stadler, E.L.

1986-08-01

Multistage Centrifugal Compressor Performance is generally presented in the form of a composite curve showing discharge pressure and bhp plotted as a function of capacity. This composite curve represents the cumulative performance of each stage performance curve. A simple yet quite accurate means of measuring compressor total performance is to test each stage as a single-stage compressor, usually on air with atmospheric inlets. Stage curves are then generated from the test data and three important variables are plotted: head coefficient, work coefficient and adiabatic efficiency. These variables are plotted against a normalized flow coefficient, Q/N, which is inlet volume flowmore » (cfm) divided by impeller speed (rpm). The nomenclature used to define these stage variables changes from manufacturer to manufacturer; however, the parameters presented are the same. An understanding of each parameter's theoretical derivation and determination from test data will help the engineer reviewing test curves to be more cognizant of the interrelationships between these variables; specifically, how they affect overall machine pressure rise and power consumption.« less

Conceptual recurrence plots: revealing patterns in human discourse.

PubMed

Angus, Daniel; Smith, Andrew; Wiles, Janet

2012-06-01

Human discourse contains a rich mixture of conceptual information. Visualization of the global and local patterns within this data stream is a complex and challenging problem. Recurrence plots are an information visualization technique that can reveal trends and features in complex time series data. The recurrence plot technique works by measuring the similarity of points in a time series to all other points in the same time series and plotting the results in two dimensions. Previous studies have applied recurrence plotting techniques to textual data; however, these approaches plot recurrence using term-based similarity rather than conceptual similarity of the text. We introduce conceptual recurrence plots, which use a model of language to measure similarity between pairs of text utterances, and the similarity of all utterances is measured and displayed. In this paper, we explore how the descriptive power of the recurrence plotting technique can be used to discover patterns of interaction across a series of conversation transcripts. The results suggest that the conceptual recurrence plotting technique is a useful tool for exploring the structure of human discourse.

Defining the learning curve in laparoscopic paraesophageal hernia repair: a CUSUM analysis.

PubMed

Okrainec, Allan; Ferri, Lorenzo E; Feldman, Liane S; Fried, Gerald M

2011-04-01

There are numerous reports in the literature documenting high recurrence rates after laparoscopic paraesophageal hernia repair. The purpose of this study was to determine the learning curve for this procedure using the Cumulative Summation (CUSUM) technique. Forty-six consecutive patients with paraesophageal hernia were evaluated prospectively after laparoscopic paraesophageal hernia repair. Upper GI series was performed 3 months postoperatively to look for recurrence. Patients were stratified based on the surgeon's early (first 20 cases) and late experience (>20 cases). The CUSUM method was then used to further analyze the learning curve. Nine patients (21%) had anatomic recurrence. There was a trend toward a higher recurrence rate during the first 20 cases, although this did not achieve statistical significance (33% vs. 13%, p = 0.10). However, using a CUSUM analysis to plot the learning curve, we found that the recurrence rate diminishes after 18 cases and reaches an acceptable rate after 26 cases. Surgeon experience is an important predictor of recurrence after laparoscopic paraesophageal hernia repair. CUSUM analysis revealed there is a significant learning curve to become proficient at this procedure, with approximately 20 cases required before a consistent decrease in hernia recurrence rate is observed.

The Nasa earth resources spectral information system: A data compilation, first supplement

NASA Technical Reports Server (NTRS)

Leeman, V.

1972-01-01

The NASA Earth Resources Spectral Information System and the information contained therein are described. It is intended to be used as a supplement to the NASA Earth Resources Spectral Information System: A Data Compilation, N72-28366. This supplement includes approximately 500 rock and mineral, 100 soil, and 30 vegetation bidirectional and directional reflectance, transmittance, emittance, and degree-of-polarization curves in the optical region from 0.2 to 22.0 microns. The data have been categorized by subject and each curve plotted on a single graph. For some rocks and minerals, all curves of the same type, differing only in particle size, have been plotted on one grid as a composite plot. Each graph, composite or single, is fully titled to indicate curve source and is indexed by subject to facilitate user retrieval.

Application of the compensated Arrhenius formalism to explain the dielectric constant dependence of rates for Menschutkin reactions.

PubMed

Petrowsky, Matt; Glatzhofer, Daniel T; Frech, Roger

2013-11-21

The dependence of the reaction rate on solvent dielectric constant is examined for the reaction of trihexylamine with 1-bromohexane in a series of 2-ketones over the temperature range 25-80 °C. The rate constant data are analyzed using the compensated Arrhenius formalism (CAF), where the rate constant assumes an Arrhenius-like equation that also contains a dielectric constant dependence in the exponential prefactor. The CAF activation energies are substantially higher than those obtained using the simple Arrhenius equation. A master curve of the data is observed by plotting the prefactors against the solvent dielectric constant. The master curve shows that the reaction rate has a weak dependence on dielectric constant for values approximately less than 10 and increases more rapidly for dielectric constant values greater than 10.

Autonomous Sensor Motes Employing Liquid-Bearing Rotary Stages

DTIC Science & Technology

2014-03-06

breaks off (Fig. 27d) as shown in the sudden change in force, indicating rotor pull off. The minimum of each curve indicates the maximum tensile load...configuration, with marks on the curves at the minimum energy positions are shown in Fig. 39. The minimum energy positions from Fig. 39are plotted as...rates between 5 and 17 Hz rotation rate plotted vs. rotor eccentricity. The minimum energy positions are indicated on each curve . 3.3 Discussion

Faithfulness of Recurrence Plots: A Mathematical Proof

NASA Astrophysics Data System (ADS)

Hirata, Yoshito; Komuro, Motomasa; Horai, Shunsuke; Aihara, Kazuyuki

It is practically known that a recurrence plot, a two-dimensional visualization of time series data, can contain almost all information related to the underlying dynamics except for its spatial scale because we can recover a rough shape for the original time series from the recurrence plot even if the original time series is multivariate. We here provide a mathematical proof that the metric defined by a recurrence plot [Hirata et al., 2008] is equivalent to the Euclidean metric under mild conditions.

Composite recovery type curves in normalized time from Theis' exact solution

USGS Publications Warehouse

Goode, Daniel J.

1997-01-01

Type curves derived from Theis’ exact nonequilibrium well function solution are proposed for graphical estimation of aquifer hydraulic properties, transmissivity (T), and storage coefficient (S), from water-level recovery data after cessation of a constant-rate discharge test. Drawdown (on log scale) is plotted versus the ratio of time since pumping stopped to duration of pumping, a normalized time. Under Theis conditions, individual type curves depend on only the dimensionless pumping duration, which depends in turn on S and radial distance from the pumping well. Type curve matching, in contrast to the Theis procedure for pumping data, is performed by shifting only the drawdown axis; the time axis is fixed because it is a relative or normalized time. The match-point for the drawdown axis is used to compute T, and S is determined from matching the curve shape, which depends on early dimensionless-time data. Multiple well data can be plotted and matched simultaneously (a composite plot), with drawdown at different radial distances matching different curves. The ratio of dimensionless pumping durations for any two matched curves is equal to one over the squared ratio of radial distances. Application to two recovery datasets from the literature confirm the utility of these type curves in normalized time for composite estimation of T and S.

The NASA earth resources spectral information system: A data compilation

NASA Technical Reports Server (NTRS)

Leeman, V.; Earing, D.; Vincent, R. K.; Ladd, S.

1971-01-01

The NASA Earth Resources Spectral Information System and the information contained therein are described. It contains an ordered, indexed compilation of natural targets in the optical region from 0.3 to 45.0 microns. The data compilation includes approximately 100 rock and mineral, 2600 vegetation, 1000 soil, and 60 water spectral reflectance, transmittance, and emittance curves. Most of the data have been categorized by subject, and the curves in those subject areas have been plotted on a single graph. Those categories with too few curves and miscellaneous categories have been plotted as single-curve graphs. Each graph, composite of single, is fully titled to indicate curve source and is indexed by subject to facilitate user retrieval.

Identifying hidden common causes from bivariate time series: a method using recurrence plots.

PubMed

Hirata, Yoshito; Aihara, Kazuyuki

2010-01-01

We propose a method for inferring the existence of hidden common causes from observations of bivariate time series. We detect related time series by excessive simultaneous recurrences in the corresponding recurrence plots. We also use a noncoverage property of a recurrence plot by the other to deny the existence of a directional coupling. We apply the proposed method to real wind data.

Sediment Dynamics in a Vegetated Tidally Influenced Interdistributary Island: Wax Lake, Louisiana

DTIC Science & Technology

2017-07-01

60 Appendix A: Time Series of Wax Lake Hydrological Measurements...north-south wind stress (right). In each plot, the global wavelet spectrum is shown to the right of the wavelet plot, and and the original time series ...for Hs. The global wavelet spectrum is shown to the right of the wavelet plot, and and the original time series is shown below

The Performance and Scientific Rationale for an Infrared Imaging Fourier Transform Spectrograph on a Large Space Telescope

DTIC Science & Technology

1998-06-22

micromirrors . Thus, an IFTS will produce a rich scientific legacy with tremendous potential for serendipity. Table 1 details the capabilities of an IFTS...maintain modulation efficiency. Curves are plotted for resolutions , 105, and 1064R 5 k/dk 5 10 assuming an 8 m diameter primary aperture and a beam splitter...passbands centered at 1.1, 1.3, 1.7, 2.3, and 3.6 mm. Colors are plotted from ; a triangle is plotted at every interval of unit redshift. These curves

Simplified plotting package for the LSI-11 computer and Tektronix terminals

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

Henline, P.

1980-12-01

These plotting subroutines were written to allow the user to do plotting easily and quickly, but do not contain many fancy features in order to minimize memory space. Plots are produced of real values only. The first element of the plotting array contains the number of points to plot and the values to plot are stored in the remaining array locations. The maximum number of points which can be plotted is 300. The user must provide titles and other alpha numeric information. This can be done easily by a call to LOCATE, then ALPHA, and then doing a FORTRAN write.more » LOCATE and ALPHA are part of the Oak Ridge TEK11 Graphics Package. All plots are framed and labeled. The X axis has ten tick marks and three labels (left, center, and right side) and the Y axis has three tick marks and three labels. The subroutines assume the user is smart. Curves (especially when more than one is drawn on one plot) are assumed to be completely within the defined area as no clipping or dark lines are drawn. The user has the ability to do multiple curves on one graph or multiple graphs on a page.« less

Analysis of vegetation in an Imperata grassland of Barak valley, Assam.

PubMed

Astapati, Ashim Das; Das, Ashesh Kumar

2012-09-01

Imperata grassland at Dorgakona, Barak valley, North Eastern India was analyzed for species composition and diversity pattern in relation to traditional management practices. 19 families were in the burnt and unburnt plots of the study site with Poaceae as the most dominant one. 29 species occurred in the burnt plot and 28 in the unburnt plot. Most of the species were common in both the plots. The pattern of frequency diagrams indicated that the vegetation was homogeneous. Imperata cylindrica, a rhizomatous grass was the dominant species based on density (318.75 and 304.18 nos. m(-2)), basal cover (158.22 and 148.34 cm2 m(-2)) and Importance value index (IVI) (132.64 and 138.74) for the burnt and unburnt plots respectively. Borreria pusilla was the co-dominant species constituting Imperata-Borreria assemblage of the studied grassland. It was observed that B. pusilla (162.25 nos. m(-2) and 50.37 nos. m(-2), I. cylindrica (318.75 nos. m(-2) and 304.18 nos. m(-2)) and Setaria glauca (24.70 nos. m(-2) and 16.46 nos. m(-2) were benefited from burning as shown by the values sequentially placed for burnt and unburnt plots. Certain grasses like Chrysopogon aciculatus and Sacciolepis indica were restricted to burnt plot while Oxalis corniculata showed its presence to unburnt plot. Grasses dominated the grassland as revealed by their contribution to the mean percentage cover of 72% in burnt plot and 76% in umburnt plot. The dominance-diversity curves in the study site approaches a log normal series distribution suggesting that the resources are shared by the constituent species. Seasonal pattern in diversity index suggested definite influence of climatic seasonality on species diversity; rainy season was conducive for maximum diversity (1.40 and 1.38 in the burnt and unburnt plots, respectively). Dominance increased with concentration of fewer species (0.0021 in burnt plot and 0.0055 in unbumt plot) in summer and behaves inversely to index of diversity. This study showed that the traditional management practices benefits the farmers as it promote grassland regeneration with I. cylindrica as the dominant grass.

Manufacturing complexity analysis

NASA Technical Reports Server (NTRS)

Delionback, L. M.

1977-01-01

The analysis of the complexity of a typical system is presented. Starting with the subsystems of an example system, the step-by-step procedure for analysis of the complexity of an overall system is given. The learning curves for the various subsystems are determined as well as the concurrent numbers of relevant design parameters. Then trend curves are plotted for the learning curve slopes versus the various design-oriented parameters, e.g. number of parts versus slope of learning curve, or number of fasteners versus slope of learning curve, etc. Representative cuts are taken from each trend curve, and a figure-of-merit analysis is made for each of the subsystems. Based on these values, a characteristic curve is plotted which is indicative of the complexity of the particular subsystem. Each such characteristic curve is based on a universe of trend curve data taken from data points observed for the subsystem in question. Thus, a characteristic curve is developed for each of the subsystems in the overall system.

System and process for ultrasonic characterization of deformed structures

DOEpatents

Panetta, Paul D [Williamsburg, VA; Morra, Marino [Richland, WA; Johnson, Kenneth I [Richland, WA

2011-11-22

Generally speaking, the method of the present invention is performed by making various ultrasonic scans at preselected orientations along the length of a material being tested. Data from the scans are then plotted together with various calculated parameters that are calculated from this data. Lines or curves are then fitted to the respective plotted points. Review of these plotted curves allows the location and severity of defects within these sections to be determined and quantified. With this information various other decisions related to how, when or whether repair or replacement of a particular portion of a structure can be made.

Atlas of Secular Light Curves of Comets

NASA Astrophysics Data System (ADS)

Ferrin, Ignacio

2007-12-01

We have completed work on the secular light curves of 30 periodic and non-periodic comets. The objectives and approach of this project has been explained in Ferrin (Icarus, 178, 493-516, 2005). Each comet requires 2 plots. The time plot shows the reduced (to Δ = 1 AU) magnitude of the comet as a function of time, thus displaying the brightness history of the object. The log plot is a reflected double log plot. The reflection takes place at R=1 AU, to allow the determination of the absolute magnitude by extrapolation. 22 photometric parameters are measured from the plots, most of them new. The plots have been collected in a document that constitutes "The Atlas". We have defined a photometric age, P-AGE, that attempts to measure the age of a comet based on its activity. P-AGE has been scaled to human ages to help in its interpretation. We find that comets Hale-Bopp and 29P/SW 1, are baby comets (P-AGE < 3 comet years), while 107P, 162P and 169P are methuselah comets (P-AGE > 100 cy). The secular light curve of 9P/Tempel 1 exhibits sublimation due to H2O and due to CO. Comet 67P/Churyumov-Gerasimento to be visited by the Rossetta spacecraft in 2014 exhibits a photometric anomaly. Comet 65P/Gunn exhibits a lag in maximum brightness of LAG = + 254 days after perihelion. We suggest that the pole is pointing to the sun at that time. The secular light curves will be presented and a preliminary interpretation will be advanced. The secular light curves present complexity beyond current understanding. The observations described in this work were carried out at the National Observatory of Venezuela (ONV), managed by the Center for Research in Astronomy (CIDA), for the Ministry of Science and Technology (MinCyT).

Covalent character and electric field dependence of H2-AgX (X = F - I).

PubMed

Li, Xinying

2018-06-16

Mechanisms of Ag-X and Ag…H 2 interactions and stabilities of T-shaped H 2 -AgX (X = F - I) series were investigated at the CCSD(T) level. The "no-density" bond with smaller positive Laplacian and ELF values in interaction regions, as well as considerable delocalization index values, suggest weak covalent "charge-shift" character for the Ag…H 2 interaction. Structure and stability dependence on the electric field were investigated at the MP2 level. Relative total energy curves show obvious parabolic character, and the plots can be fitted by quadratic polynomials as functions of electric field strength.

Constitutive modeling of the human Anterior Cruciate Ligament (ACL) under uniaxial loading using viscoelastic prony series and hyperelastic five parameter Mooney-Rivlin model

NASA Astrophysics Data System (ADS)

Chakraborty, Souvik; Mondal, Debabrata; Motalab, Mohammad

2016-07-01

In this present study, the stress-strain behavior of the Human Anterior Cruciate Ligament (ACL) is studied under uniaxial loads applied with various strain rates. Tensile testing of the human ACL samples requires state of the art test facilities. Furthermore, difficulty in finding human ligament for testing purpose results in very limited archival data. Nominal Stress vs. deformation gradient plots for different strain rates, as found in literature, is used to model the material behavior either as a hyperelastic or as a viscoelastic material. The well-known five parameter Mooney-Rivlin constitutivemodel for hyperelastic material and the Prony Series model for viscoelastic material are used and the objective of the analyses comprises of determining the model constants and their variation-trend with strain rates for the Human Anterior Cruciate Ligament (ACL) material using the non-linear curve fitting tool. The relationship between the model constants and strain rate, using the Hyperelastic Mooney-Rivlin model, has been obtained. The variation of the values of each coefficient with strain rates, obtained using Hyperelastic Mooney-Rivlin model are then plotted and variation of the values with strain rates are obtained for all the model constants. These plots are again fitted using the software package MATLAB and a power law relationship between the model constants and strain rates is obtained for each constant. The obtained material model for Human Anterior Cruciate Ligament (ACL) material can be implemented in any commercial finite element software package for stress analysis.

From fuzzy recurrence plots to scalable recurrence networks of time series

NASA Astrophysics Data System (ADS)

Pham, Tuan D.

2017-04-01

Recurrence networks, which are derived from recurrence plots of nonlinear time series, enable the extraction of hidden features of complex dynamical systems. Because fuzzy recurrence plots are represented as grayscale images, this paper presents a variety of texture features that can be extracted from fuzzy recurrence plots. Based on the notion of fuzzy recurrence plots, defuzzified, undirected, and unweighted recurrence networks are introduced. Network measures can be computed for defuzzified recurrence networks that are scalable to meet the demand for the network-based analysis of big data.

Relative equilibrium plot improves graphical analysis and allows bias correction of standardized uptake value ratio in quantitative 11C-PiB PET studies.

PubMed

Zhou, Yun; Sojkova, Jitka; Resnick, Susan M; Wong, Dean F

2012-04-01

Both the standardized uptake value ratio (SUVR) and the Logan plot result in biased distribution volume ratios (DVRs) in ligand-receptor dynamic PET studies. The objective of this study was to use a recently developed relative equilibrium-based graphical (RE) plot method to improve and simplify the 2 commonly used methods for quantification of (11)C-Pittsburgh compound B ((11)C-PiB) PET. The overestimation of DVR in SUVR was analyzed theoretically using the Logan and the RE plots. A bias-corrected SUVR (bcSUVR) was derived from the RE plot. Seventy-eight (11)C-PiB dynamic PET scans (66 from controls and 12 from participants with mild cognitive impaired [MCI] from the Baltimore Longitudinal Study of Aging) were acquired over 90 min. Regions of interest (ROIs) were defined on coregistered MR images. Both the ROI and the pixelwise time-activity curves were used to evaluate the estimates of DVR. DVRs obtained using the Logan plot applied to ROI time-activity curves were used as a reference for comparison of DVR estimates. Results from the theoretic analysis were confirmed by human studies. ROI estimates from the RE plot and the bcSUVR were nearly identical to those from the Logan plot with ROI time-activity curves. In contrast, ROI estimates from DVR images in frontal, temporal, parietal, and cingulate regions and the striatum were underestimated by the Logan plot (controls, 4%-12%; MCI, 9%-16%) and overestimated by the SUVR (controls, 8%-16%; MCI, 16%-24%). This bias was higher in the MCI group than in controls (P < 0.01) but was not present when data were analyzed using either the RE plot or the bcSUVR. The RE plot improves pixelwise quantification of (11)C-PiB dynamic PET, compared with the conventional Logan plot. The bcSUVR results in lower bias and higher consistency of DVR estimates than of SUVR. The RE plot and the bcSUVR are practical quantitative approaches that improve the analysis of (11)C-PiB studies.

Enhancement of the Daytime MODIS Based Aircraft Icing Potential Algorithm Using Mesoscale Model Data

DTIC Science & Technology

2006-03-01

January, 15, 2006 ...... 37 x Figure 25. ROC curves using 3 hour PIREPs and Alexander Tmap with symbols plotted at the 0.5 threshold values...42 Figure 26. ROC curves using 3 hour PIREPs and Alexander Tmap with symbols plotted at the 0.5 threshold values...Table 4. Results using T icing potential values from the Alexander Tmap , and 3 Hour PIREPs

Recurrence plots and recurrence quantification analysis of human motion data

NASA Astrophysics Data System (ADS)

Josiński, Henryk; Michalczuk, Agnieszka; Świtoński, Adam; Szczesna, Agnieszka; Wojciechowski, Konrad

2016-06-01

The authors present exemplary application of recurrence plots, cross recurrence plots and recurrence quantification analysis for the purpose of exploration of experimental time series describing selected aspects of human motion. Time series were extracted from treadmill gait sequences which were recorded in the Human Motion Laboratory (HML) of the Polish-Japanese Academy of Information Technology in Bytom, Poland by means of the Vicon system. Analysis was focused on the time series representing movements of hip, knee, ankle and wrist joints in the sagittal plane.

A theoretical study of interaction effects on the remanence curves of particulate dispersions

NASA Astrophysics Data System (ADS)

Fearon, M.; Chantrell, R. W.; Wohlfarth, E. P.

1990-05-01

The remanence curves of strongly interacting fine-particle systems are investigated theoretically. It is shown that the Henkel plot of the dc demagnetisation remanence vs. the isothermal remanence is a useful representation of interactions. The form of the plot is found to be a reflection of the magnetic and physical microstructure of the material, which is consistent with experimental data. The relationship between the Henkel plot and the noise of a particulate recording medium, another property dependent on the microstructure, is also considered. The Interaction Field Factor (IFF), a single parameter characterising the non-linearity of the Henkel plot, is also investigated. The results are consistent with a previous experimental study. Finally, the effect of interactions on the Switching Field Distribution are investigated.

A method for analyzing temporal patterns of variability of a time series from Poincare plots.

PubMed

Fishman, Mikkel; Jacono, Frank J; Park, Soojin; Jamasebi, Reza; Thungtong, Anurak; Loparo, Kenneth A; Dick, Thomas E

2012-07-01

The Poincaré plot is a popular two-dimensional, time series analysis tool because of its intuitive display of dynamic system behavior. Poincaré plots have been used to visualize heart rate and respiratory pattern variabilities. However, conventional quantitative analysis relies primarily on statistical measurements of the cumulative distribution of points, making it difficult to interpret irregular or complex plots. Moreover, the plots are constructed to reflect highly correlated regions of the time series, reducing the amount of nonlinear information that is presented and thereby hiding potentially relevant features. We propose temporal Poincaré variability (TPV), a novel analysis methodology that uses standard techniques to quantify the temporal distribution of points and to detect nonlinear sources responsible for physiological variability. In addition, the analysis is applied across multiple time delays, yielding a richer insight into system dynamics than the traditional circle return plot. The method is applied to data sets of R-R intervals and to synthetic point process data extracted from the Lorenz time series. The results demonstrate that TPV complements the traditional analysis and can be applied more generally, including Poincaré plots with multiple clusters, and more consistently than the conventional measures and can address questions regarding potential structure underlying the variability of a data set.

High-latitude geomagnetic disturbances during ascending solar cycle 24

NASA Astrophysics Data System (ADS)

Peitso, Pyry; Tanskanen, Eija; Stolle, Claudia; Berthou Lauritsen, Nynne; Matzka, Jürgen

2015-04-01

High-latitude regions are very convenient for study of several space weather phenomena such as substorms. Large geographic coverage as well as long time series of data are essential due to the global nature of space weather and the long duration of solar cycles. We will examine geomagnetic activity in Greenland from magnetic field measurements taken by DTU (Technical University of Denmark) magnetometers during the years 2010 to 2014. The study uses data from 13 magnetometer stations located on the east coast of Greenland and one located on the west coast. The original measurements are in one second resolution, thus the amount of data is quite large. Magnetic field H component (positive direction towards the magnetic north) was used throughout the study. Data processing will be described from calibration of original measurements to plotting of long time series. Calibration consists of determining the quiet hour of a given day and reducing the average of that hour from all the time steps of the day. This normalizes the measurements and allows for better comparison between different time steps. In addition to the full time line of measurements, daily, monthly and yearly averages will be provided for all stations. Differential calculations on the change of the H component will also be made available for the duration of the full data set. Envelope curve plots will be presented for duration of the time line. Geomagnetic conditions during winter and summer will be compared to examine seasonal variation. Finally the measured activity will be compared to NOAA (National Oceanic and Atmospheric Administration) issued geomagnetic space weather alerts from 2010 to 2014. Calculations and plotting of measurement data were done with MATLAB. M_map toolbox was used for plotting of maps featured in the study (http://www2.ocgy.ubc.ca/~rich/map.html). The study was conducted as a part of the ReSoLVE (Research on Solar Long-term Variability and Effects) Center of Excellence.

Coarse-graining time series data: Recurrence plot of recurrence plots and its application for music

NASA Astrophysics Data System (ADS)

Fukino, Miwa; Hirata, Yoshito; Aihara, Kazuyuki

2016-02-01

We propose a nonlinear time series method for characterizing two layers of regularity simultaneously. The key of the method is using the recurrence plots hierarchically, which allows us to preserve the underlying regularities behind the original time series. We demonstrate the proposed method with musical data. The proposed method enables us to visualize both the local and the global musical regularities or two different features at the same time. Furthermore, the determinism scores imply that the proposed method may be useful for analyzing emotional response to the music.

Coarse-graining time series data: Recurrence plot of recurrence plots and its application for music.

PubMed

Fukino, Miwa; Hirata, Yoshito; Aihara, Kazuyuki

2016-02-01

We propose a nonlinear time series method for characterizing two layers of regularity simultaneously. The key of the method is using the recurrence plots hierarchically, which allows us to preserve the underlying regularities behind the original time series. We demonstrate the proposed method with musical data. The proposed method enables us to visualize both the local and the global musical regularities or two different features at the same time. Furthermore, the determinism scores imply that the proposed method may be useful for analyzing emotional response to the music.

Intraday X-Ray Variability of QSOs/AGN Using the Chandra Archives

NASA Astrophysics Data System (ADS)

Tartamella, C.; Busche, J.

2005-05-01

X-ray variability is a common characteristic of Active Galactic Nuclei (AGN), and it can be used to probe the nuclear region at short time scales. Quantitative analysis of this variability has been difficult due to low signal-to-noise ratios and short time baselines, but serendipitous Chandra data acquired within the last six years have opened the door to such analysis. Cross-correlation of the Chandra archives with QSO/AGN catalogs on NASA's HEASARC website (e.g. Veron, Sloan) yields a sample of 50+ objects that satisfy the following criteria: absolute magnitude M≤ -22.5, proper time baselines greater than 2 hours, and count rates leading to 10% error bars for 8+ flux points on the light curve. The sample includes a range of red-shifts, magnitudes, and type (e.g. radio loud, radio quiet), and hence may yield empirical clues about luminosity or evolutionary trends. As a beginning of such analysis, we present 11 light curves for 9 objects for which the exposure time was greater than 10 hours. The variability was analyzed using three different statistical methods. The Kolmogorov-Smirnov (KS) test proved to be impractical because of the unavoidably small number of data points and the simplistic nature of the test. A χ2 test indicated in most cases that there were significant departures from constant brightness (as expected). Autocorrelation plots were also generated for each light curve. With more work and a larger sample size, these plots can be used to identify any trends in the lightcurve such as whether the variability is stochastic or periodic in nature. This test was useful even with the small number of datapoints available. In future work, more sophisticated analyses based on Fourier series, power density spectra, or wavelets are likely to yield more meaningful and useful results.

Lagged segmented Poincaré plot analysis for risk stratification in patients with dilated cardiomyopathy.

PubMed

Voss, Andreas; Fischer, Claudia; Schroeder, Rico; Figulla, Hans R; Goernig, Matthias

2012-07-01

The objectives of this study were to introduce a new type of heart-rate variability analysis improving risk stratification in patients with idiopathic dilated cardiomyopathy (DCM) and to provide additional information about impaired heart beat generation in these patients. Beat-to-beat intervals (BBI) of 30-min ECGs recorded from 91 DCM patients and 21 healthy subjects were analyzed applying the lagged segmented Poincaré plot analysis (LSPPA) method. LSPPA includes the Poincaré plot reconstruction with lags of 1-100, rotating the cloud of points, its normalized segmentation adapted to their standard deviations, and finally, a frequency-dependent clustering. The lags were combined into eight different clusters representing specific frequency bands within 0.012-1.153 Hz. Statistical differences between low- and high-risk DCM could be found within the clusters II-VIII (e.g., cluster IV: 0.033-0.038 Hz; p = 0.0002; sensitivity = 85.7 %; specificity = 71.4 %). The multivariate statistics led to a sensitivity of 92.9 %, specificity of 85.7 % and an area under the curve of 92.1 % discriminating these patient groups. We introduced the LSPPA method to investigate time correlations in BBI time series. We found that LSPPA contributes considerably to risk stratification in DCM and yields the highest discriminant power in the low and very low-frequency bands.

Piezoresistive strain sensing of carbon black /silicone composites above percolation threshold

NASA Astrophysics Data System (ADS)

Shang, Shuying; Yue, Yujuan; Wang, Xiaoer

2016-12-01

A series of flexible composites with a carbon black (CB) filled silicone rubber matrix were made by an improved process in this work. A low percolation threshold with a mass ratio of 2.99% CB was achieved. The piezoresistive behavior of CB/silicone composites above the critical value, with the mass ratio of carbon black to the silicone rubber ranging from 0.01 to 0.2, was studied. The piezoresistive behavior was different from each other for the composites with different CB contents. But, the composites show an excellent repeatability of piezoresistivity under cyclic compression, no matter with low filler content or with high filler content. The most interesting phenomena were that the plots of gauge factor versus strain of the composites with different CB contents constructed a master curve and the curve could be well fitted by a function. It was showed that the gauge factor of the composites was strain-controlled showing a promising prospect of application.

Determining density of maize canopy. 3: Temporal considerations

NASA Technical Reports Server (NTRS)

Stoner, E. R.; Baumgardner, M. F.; Anuta, P. E.; Cipra, J. E.

1972-01-01

Multispectral scanner data were collected in two flights over ground cover plots at an altitude of 305 m. Eight ground reflectance panels in close proximity to the ground cover plots were used to normalize the scanner data obtained on different dates. Separate prediction equations were obtained for both flight dates for all eleven reflective wavelength bands of the multispectral scanner. Ratios of normalized scanner data were related to leaf area index over time. Normalized scanner data were used to plot relative reflectance versus wavelength for the ground cover plots. Spectral response curves were similar to those for bare soil and green vegetation as determined by laboratory measurements. The spectral response curves from the normalized scanner data indicated that reflectance in the 0.72 to 1.3 micron wavelength range increased as leaf area index increased. A decrease in reflectance was observed in the 0.65 micron chlorophyll absorption band as leaf area index increased.

Return period curves for extreme 5-min rainfall amounts at the Barcelona urban network

NASA Astrophysics Data System (ADS)

Lana, X.; Casas-Castillo, M. C.; Serra, C.; Rodríguez-Solà, R.; Redaño, A.; Burgueño, A.; Martínez, M. D.

2018-03-01

Heavy rainfall episodes are relatively common in the conurbation of Barcelona and neighbouring cities (NE Spain), usually due to storms generated by convective phenomena in summer and eastern and south-eastern advections in autumn. Prevention of local flood episodes and right design of urban drainage have to take into account the rainfall intensity spread instead of a simple evaluation of daily rainfall amounts. The database comes from 5-min rain amounts recorded by tipping buckets in the Barcelona urban network along the years 1994-2009. From these data, extreme 5-min rain amounts are selected applying the peaks-over-threshold method for thresholds derived from both 95% percentile and the mean excess plot. The return period curves are derived from their statistical distribution for every gauge, describing with detail expected extreme 5-min rain amounts across the urban network. These curves are compared with those derived from annual extreme time series. In this way, areas in Barcelona submitted to different levels of flood risk from the point of view of rainfall intensity are detected. Additionally, global time trends on extreme 5-min rain amounts are quantified for the whole network and found as not statistically significant.

Using US Forest Inventory (FIA) Data to Test for Growth Enhancement

NASA Astrophysics Data System (ADS)

Masek, J. G.; Collatz, G. J.; Williams, C. A.

2015-12-01

It is recognized that land ecosystems sequester a significant fraction of anthropogenic carbon emissions, and that the magnitude of the "land sink" appears to be increasing through time. This observation has led to the hypothesis that forest ecosystems are experiencing more rapid growth than their historical norm, due to some combination of CO2 fertilization, longer growing seasons, nitrogen deposition, and more intensive management. Direct evidence for growth enhancment has been reported from experimental plots, where long-term (historical) rates of biomass accumulation appear lower than contemporary rates derived from remeasurement of individual trees. However, the approach has not been pursued at a national scale. Since the late 1990's the US Forest Inventory and Analysis (FIA) program has standardized plot locations across the United States, and has systematically remeasured tree and plot attributes on 5-year (east) or 10-year (west) cycles. In principle, these remeasured plots provide a robust dataset for comparing contemporary and historical growth rates. In this talk we review approaches for performing this comparison at both plot and tree scales. We find that recent plot-level biomass accumulation rates from the eastern US do show more rapid growth than would be expected from historical biomass-age curves, with enhancement factors of up 2x. However, the implicit inclusion of "cryptic" or older disturbances in the historical curves hinders a definitive interpretation. Stand-level age-biomass simulations confirm that disturbance events must be included in the remeasured data set in order to provide comparability with historical curves. Remeasured DBH measurements from individual trees may provide a more robust approach for examining the issue.

A compact presentation of DSN array telemetry performance

NASA Technical Reports Server (NTRS)

Greenhall, C. A.

1982-01-01

The telemetry performance of an arrayed receiver system, including radio losses, is often given by a family of curves giving bit error rate vs bit SNR, with tracking loop SNR at one receiver held constant along each curve. This study shows how to process this information into a more compact, useful format in which the minimal total signal power and optimal carrier suppression, for a given fixed bit error rate, are plotted vs data rate. Examples for baseband-only combining are given. When appropriate dimensionless variables are used for plotting, receiver arrays with different numbers of antennas and different threshold tracking loop bandwidths look much alike, and a universal curve for optimal carrier suppression emerges.

SigmaPlot 2000, Version 6.00, SPSS Inc. Computer Software Project Management, Requirements, and Design Document

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

HURLBUT, S.T.

2000-10-24

SigmaPlot is a vendor software product that will be used to convert the area under an absorbance curve generated by a Fourier transform infrared spectrometer (FTIR) to a relative area. SigmaPlot will be used in conjunction with procedure ZA-565-301, ''Determination of Moisture by Supercritical Fluid Extraction and Infrared Detection.''

A new method to study ferroelectrics using the remanent Henkel plots

NASA Astrophysics Data System (ADS)

Vopson, Melvin M.

2018-05-01

Analysis of experimental curves constructed from dc demagnetization and isothermal remanent magnetization known as Henkel and delta M plots, have served for over 53 years as an important tool for characterization of interactions in ferromagnets. In this article we address the question whether the same experimental technique could be applied to the study of ferroelectric systems. The successful measurement of the equivalent dc depolarisation and isothermal remanent polarization curves and the construction of the Henkel and delta P plots for ferroelectrics is reported here. Full measurement protocol is provided together with experimental examples for two ferroelectric ceramic samples. This new measurement technique is an invaluable experimental tool that could be used to further advance our understanding of ferroelectric materials and their applications.

Statistics of Smoothed Cosmic Fields in Perturbation Theory. I. Formulation and Useful Formulae in Second-Order Perturbation Theory

NASA Astrophysics Data System (ADS)

Matsubara, Takahiko

2003-02-01

We formulate a general method for perturbative evaluations of statistics of smoothed cosmic fields and provide useful formulae for application of the perturbation theory to various statistics. This formalism is an extensive generalization of the method used by Matsubara, who derived a weakly nonlinear formula of the genus statistic in a three-dimensional density field. After describing the general method, we apply the formalism to a series of statistics, including genus statistics, level-crossing statistics, Minkowski functionals, and a density extrema statistic, regardless of the dimensions in which each statistic is defined. The relation between the Minkowski functionals and other geometrical statistics is clarified. These statistics can be applied to several cosmic fields, including three-dimensional density field, three-dimensional velocity field, two-dimensional projected density field, and so forth. The results are detailed for second-order theory of the formalism. The effect of the bias is discussed. The statistics of smoothed cosmic fields as functions of rescaled threshold by volume fraction are discussed in the framework of second-order perturbation theory. In CDM-like models, their functional deviations from linear predictions plotted against the rescaled threshold are generally much smaller than that plotted against the direct threshold. There is still a slight meatball shift against rescaled threshold, which is characterized by asymmetry in depths of troughs in the genus curve. A theory-motivated asymmetry factor in the genus curve is proposed.

Application of Lorenz curve to interpret concentration of contraception and fertility in a population.

PubMed

Ghanma, M A; Rider, R V; Sirageldin, I

1984-01-01

The Lorenz Curve, originally developed to measure the concentration of wealth in a population, was used to describe the distribution of contraceptive practice in Jordan. Data from the 1976 Jordan Fertility Study, carried out as part of the World Fertility Survey program, was used in the analysis. The application of the Automatic Interaction Detector program to the survey's sample population of 3611 women of reproductive age divided the sample into 6 mutually exclusive groups on the basis of residence, education, and whether desired family size was attained or not attained. These 3 characteristics accounted for a major portion of the variation in contraceptive practice. These subgroups, in ascending order by the proportion practicing contraception, were: 1) rural women with unattained desired family size; 2) urban, illiterate women with unattained desired family size; 3) rural women with attained desired family size; 4) urban, literate women with unattained desired family size; 5) urban, illiterate women with attained desired family size; and 6) urban, literate women with attained desired family size. The cumulative proportion of the sample in each ordered subdivision was plotted on the X axis of a graph, and the cumulative proportion of those practicing contraception was plotted on the Y axis of the graph. A line connecting the intersection of the points on the X and Y axis was then drawn. The resultant line was a concave ascending line. If contraceptive practice was evenly distributed in the population, the line would be a straight diagonal line. The plotted curved line indicated that contraceptive practice was unevenly distributed in the population. 2 indexes for measuring the area between the diagonal and the line resulting from plotting the observed distribution for each subgroup was used to assess the degree of concentration of contraceptive practice in the population. The indexes also indicated that contraceptive practice was unequally distributed. When separate curves were plotted for the subgroups with attained desired family size and the subgroups without attained desired family size, it was apparent that the distribution of contraceptive practice was more uniform among those with attained desired family size than among the other 3 subgroups. A curve for the distribution of births was then plotted on the same graph. This curve was not a true application of the Lorenz Curve since it was based on the order of the subdivisions by birth rates. The resultant line approached the straight diagonal line and indicated that the distribution of births was fairly evenly distributed in the population. The uneven distribution of contraceptive practice and the uniform distribution of births suggests that contraceptive practice in this population is ineffective. This may be a characteristic of populations in the early stages of fertility control.

Species-area curves indicate the importance of habitats' contributions to regional biodiversity

USGS Publications Warehouse

Chong, G.W.; Stohlgren, T.J.

2007-01-01

We examined species-area curves, species composition and similarity (Jaccard's coefficients), and species richness in 17 vegetation types to develop a composite index of a vegetation type's contribution to regional species richness. We collected data from 1 to 1000 m2 scales in 147 nested plots in Rocky Mountain National Park, Colorado, USA to compare three species-area curve models' abilities to estimate the number of species observed in each vegetation type. The log(species)-log(area) curve had the largest adjusted coefficients of determination (r2 values) in 12 of the 17 types, followed by the species-log(area) curve with five of the highest values. When the slopes of the curves were corrected for species overlap among plots with Jaccard's coefficients, the species-log(area) curves estimated values closest to those observed. We combined information from species-area curves and measures of heterogeneity with information on the area covered by each vegetation type and found that the types making the greatest contributions to regional biodiversity covered the smallest areas. This approach may provide an accurate and relatively rapid way to rank hotspots of plant diversity within regions of interest.

Characterization of time series via Rényi complexity-entropy curves

NASA Astrophysics Data System (ADS)

Jauregui, M.; Zunino, L.; Lenzi, E. K.; Mendes, R. S.; Ribeiro, H. V.

2018-05-01

One of the most useful tools for distinguishing between chaotic and stochastic time series is the so-called complexity-entropy causality plane. This diagram involves two complexity measures: the Shannon entropy and the statistical complexity. Recently, this idea has been generalized by considering the Tsallis monoparametric generalization of the Shannon entropy, yielding complexity-entropy curves. These curves have proven to enhance the discrimination among different time series related to stochastic and chaotic processes of numerical and experimental nature. Here we further explore these complexity-entropy curves in the context of the Rényi entropy, which is another monoparametric generalization of the Shannon entropy. By combining the Rényi entropy with the proper generalization of the statistical complexity, we associate a parametric curve (the Rényi complexity-entropy curve) with a given time series. We explore this approach in a series of numerical and experimental applications, demonstrating the usefulness of this new technique for time series analysis. We show that the Rényi complexity-entropy curves enable the differentiation among time series of chaotic, stochastic, and periodic nature. In particular, time series of stochastic nature are associated with curves displaying positive curvature in a neighborhood of their initial points, whereas curves related to chaotic phenomena have a negative curvature; finally, periodic time series are represented by vertical straight lines.

Towards a New Generation of Time-Series Visualization Tools in the ESA Heliophysics Science Archives

NASA Astrophysics Data System (ADS)

Perez, H.; Martinez, B.; Cook, J. P.; Herment, D.; Fernandez, M.; De Teodoro, P.; Arnaud, M.; Middleton, H. R.; Osuna, P.; Arviset, C.

2017-12-01

During the last decades a varied set of Heliophysics missions have allowed the scientific community to gain a better knowledge on the solar atmosphere and activity. The remote sensing images of missions such as SOHO have paved the ground for Helio-based spatial data visualization software such as JHelioViewer/Helioviewer. On the other hand, the huge amount of in-situ measurements provided by other missions such as Cluster provide a wide base for plot visualization software whose reach is still far from being fully exploited. The Heliophysics Science Archives within the ESAC Science Data Center (ESDC) already provide a first generation of tools for time-series visualization focusing on each mission's needs: visualization of quicklook plots, cross-calibration time series, pre-generated/on-demand multi-plot stacks (Cluster), basic plot zoom in/out options (Ulysses) and easy navigation through the plots in time (Ulysses, Cluster, ISS-Solaces). However, as the needs evolve and the scientists involved in new missions require to plot multi-variable data, heat maps stacks interactive synchronization and axis variable selection among other improvements. The new Heliophysics archives (such as Solar Orbiter) and the evolution of existing ones (Cluster) intend to address these new challenges. This paper provides an overview of the different approaches for visualizing time-series followed within the ESA Heliophysics Archives and their foreseen evolution.

High Energy Electron Radiation Degradation of Gallium Arsenide Solar Cells.

DTIC Science & Technology

1986-03-01

Subroutine Print Instruct ions Print / Completed/ Sample Ch . 0 Return Calculate C1 6 Print C1 IISample Ch . 2 70 -j.. .,.1-I.,.... ,.L.L...PLOTTER * 270 * AND THE CONNECTION DIAGRAM FOR THE SYSTEM MAY * 280 " * MAY BE FOUND IN CH 2, FIGURE (3). THE GPIB * 290’ * DRIVER IS REPRODUCED FROM REF...PLOT I-V CURVE ON HP 7845 PLOTTER." 2180 PRINT 2190 PRINT ř. PLOT I-V CURVE ON RGB MONITOR." 2200 PRINT 2210 PRINT Ś. WRITE I-V DATA TO FLOPPY DISK

Equations for Automotive-Transmission Performance

NASA Technical Reports Server (NTRS)

Chazanoff, S.; Aston, M. B.; Chapman, C. P.

1984-01-01

Curve-fitting procedure ensures high confidence levels. Threedimensional plot represents performance of small automatic transmission coasting in second gear. In equation for plot, PL power loss, S speed and T torque. Equations applicable to manual and automatic transmissions over wide range of speed, torque, and efficiency.

Spatial Reasoning Training Through Light Curves Of Model Asteroids

NASA Astrophysics Data System (ADS)

Ziffer, Julie; Nakroshis, Paul A.; Rudnick, Benjamin T.; Brautigam, Maxwell J.; Nelson, Tyler W.

2015-11-01

Recent research has demonstrated that spatial reasoning skills, long known to be crucial to math and science success, are teachable. Even short stints of training can improve spatial reasoning skills among students who lack them (Sorby et al., 2006). Teaching spatial reasoning is particularly valuable to women and minorities who, through societal pressure, often doubt their spatial reasoning skill (Hill et al., 2010). We have designed a hands on asteroid rotation lab that provides practice in spatial reasoning tasks while building the student’s understanding of photometry. For our tool, we mount a model asteroid, with any shape of our choosing, on a slowly rotating motor shaft, whose speed is controlled by the experimenter. To mimic an asteroid light curve, we place the model asteroid in a dark box, shine a movable light source upon our asteroid, and record the light reflected onto a moveable camera. Students may then observe changes in the light curve that result from varying a) the speed of rotation, b) the model asteroid’s orientation with respect to the motor axis, c) the model asteroid’s shape or albedo, and d) the phase angle. After practicing with our tool, students are asked to pair new objects to their corresponding light curves. To correctly pair objects to their light curves, students must imagine how light scattering off of a three dimensional rotating object is imaged on a ccd sensor plane, and then reduced to a series of points on a light curve plot. Through the use of our model asteroid, the student develops confidence in spatial reasoning skills.

Xylem vulnerability curves of canopy branches of mature trees from Caxiuana and Tapajos National Forests, Para, Brazil

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

Powell, Thomas; Moorcroft, Paul

Raw data for xylem vulnerability curves measured on upper canopy branches of mature trees from the Caxiuana and Tapajos National Forests, Para, Brazil. Tapajos samples were harvested from km67 transects, which is nearby the decommissioned throughfall-exclusion, drought-experiment plots. Caxiuana samples were harvested from trees growing in the throughfall-exclusion, drought-experiment plots. Data were collected in 2011 and 2012. Dataset includes: date of measurement, site ID, plot ID, tree ID (species, tree tag #), xylem pressure, percent loss of conductivity. Air injection method was used. Data reference: Powell et al. (2017) Differences in xylem cavitation resistance and leaf hydraulic traits explain differencesmore » in drought tolerance among mature Amazon rainforest trees. Global Change Biology.« less

Recurrence plot analysis of nonstationary data: the understanding of curved patterns.

PubMed

Facchini, A; Kantz, H; Tiezzi, E

2005-08-01

Recurrence plots of the calls of the Nomascus concolor (Western black crested gibbon) and Hylobates lar (White-handed gibbon) show characteristic circular, curved, and hyperbolic patterns superimposed to the main temporal scale of the signal. It is shown that these patterns are related to particular nonstationarities in the signal. Some of them can be reproduced by artificial signals like frequency modulated sinusoids and sinusoids with time divergent frequency. These modulations are too faint to be resolved by conventional time-frequency analysis with similar precision. Therefore, recurrence plots act as a magnifying glass for the detection of multiple temporal scales in slightly modulated signals. The detected phenomena in these acoustic signals can be explained in the biomechanical context by taking in account the role of the muscles controlling the vocal folds.

A computer program (MACPUMP) for interactive aquifer-test analysis

USGS Publications Warehouse

Day-Lewis, F. D.; Person, M.A.; Konikow, Leonard F.

1995-01-01

This report introduces MACPUMP (Version 1.0), an aquifer-test-analysis package for use with Macintosh4 computers. The report outlines the input- data format, describes the solutions encoded in the program, explains the menu-items, and offers a tutorial illustrating the use of the program. The package reads list-directed aquifer-test data from a file, plots the data to the screen, generates and plots type curves for several different test conditions, and allows mouse-controlled curve matching. MACPUMP features pull-down menus, a simple text viewer for displaying data-files, and optional on-line help windows. This version includes the analytical solutions for nonleaky and leaky confined aquifers, using both type curves and straight-line methods, and for the analysis of single-well slug tests using type curves. An executable version of the code and sample input data sets are included on an accompanying floppy disk.

CO2 and CH4 Fluxes across Polygon Geomorphic Types, Barrow, Alaska, 2006-2010

DOE Data Explorer

Tweedie,Craig; Lara, Mark

2014-09-17

Carbon flux data are reported as Net Ecosystem Exchange (NEE), Gross Ecosystem Exchange (GEE), Ecosystem Respiration (ER), and Methane (CH4) flux. Measurements were made at 82 plots across various polygon geomorphic classes at research sites on the Barrow Environmental Observatory (BEO), the Biocomplexity Experiment site on the BEO, and the International Biological Program (IBP) site a little west of the BEO. This product is a compilation of data from 27 plots as presented in Lara et al. (2012), data from six plots presented in Olivas et al. (2010); and from 49 plots described in (Lara et al. 2014). Measurements were made during the peak of the growing seasons during 2006 to 2010. At each of the measurement plots (except Olivas et al., 2010) four different thicknesses of shade cloth were used to generate CO2 light response curves. Light response curves were used to normalize photosynthetically active radiation that is diurnally variable to a peak growing season average ~400 umolm-2sec-1. At the Olivas et al. (2010) plots, diurnal patterns were characterized by repeated sampling. CO2 measurements were made using a closed-chamber photosynthesis system and CH4 measurements were made using a photo-acoustic multi-gas analyzer. In addition, plot-level measurements for thaw depth (TD), water table depth (WTD), leaf area index (LAI), and normalized difference vegetation index (NDVI) are summarized by geomorphic polygon type.

System and method for constructing filters for detecting signals whose frequency content varies with time

DOEpatents

Qian, S.; Dunham, M.E.

1996-11-12

A system and method are disclosed for constructing a bank of filters which detect the presence of signals whose frequency content varies with time. The present invention includes a novel system and method for developing one or more time templates designed to match the received signals of interest and the bank of matched filters use the one or more time templates to detect the received signals. Each matched filter compares the received signal x(t) with a respective, unique time template that has been designed to approximate a form of the signals of interest. The robust time domain template is assumed to be of the order of w(t)=A(t)cos(2{pi}{phi}(t)) and the present invention uses the trajectory of a joint time-frequency representation of x(t) as an approximation of the instantaneous frequency function {phi}{prime}(t). First, numerous data samples of the received signal x(t) are collected. A joint time frequency representation is then applied to represent the signal, preferably using the time frequency distribution series. The joint time-frequency transformation represents the analyzed signal energy at time t and frequency f, P(t,f), which is a three-dimensional plot of time vs. frequency vs. signal energy. Then P(t,f) is reduced to a multivalued function f(t), a two dimensional plot of time vs. frequency, using a thresholding process. Curve fitting steps are then performed on the time/frequency plot, preferably using Levenberg-Marquardt curve fitting techniques, to derive a general instantaneous frequency function {phi}{prime}(t) which best fits the multivalued function f(t). Integrating {phi}{prime}(t) along t yields {phi}{prime}(t), which is then inserted into the form of the time template equation. A suitable amplitude A(t) is also preferably determined. Once the time template has been determined, one or more filters are developed which each use a version or form of the time template. 7 figs.

Going Beyond, Going Further: The Preparation of Acid-Base Titration Curves.

ERIC Educational Resources Information Center

McClendon, Michael

1984-01-01

Background information, list of materials needed, and procedures used are provided for a simple technique for generating mechanically plotted acid-base titration curves. The method is suitable for second-year high school chemistry students. (JN)

Using the Arduino with MakerPlot Software for the Display of Electrical Device Characteristics

ERIC Educational Resources Information Center

Atkin, Keith

2017-01-01

This paper shows how very simple circuitry attached to an Arduino microcontroller with MakerPlot software can be used for the display of electrical characteristic curves of three commonly available devices: an ohmic resistor, an LED, and a tungsten-filament bulb.

Using the Arduino with MakerPlot software for the display of electrical device characteristics

NASA Astrophysics Data System (ADS)

Atkin, Keith

2017-11-01

This paper shows how very simple circuitry attached to an Arduino microcontroller with MakerPlot software can be used for the display of electrical characteristic curves of three commonly available devices: an ohmic resistor, an LED, and a tungsten-filament bulb.

Site and stand factors affecting height growth curves of longleaf pine plantations

Treesearch

William D. Boyer

1981-01-01

Abstract Some factors related to the form of height-over- age curves in longleaf pine plantations were identified from analyses of 660 periodically remeasured plots.Seventy percent of the variation among 32 plantations in form the growth curve was accounted for by stratifying planting sites into old fields, mechanically prepared and unprepared cut-...

Evaluation of the Soil Conservation Service curve number methodology using data from agricultural plots

NASA Astrophysics Data System (ADS)

Lal, Mohan; Mishra, S. K.; Pandey, Ashish; Pandey, R. P.; Meena, P. K.; Chaudhary, Anubhav; Jha, Ranjit Kumar; Shreevastava, Ajit Kumar; Kumar, Yogendra

2017-01-01

The Soil Conservation Service curve number (SCS-CN) method, also known as the Natural Resources Conservation Service curve number (NRCS-CN) method, is popular for computing the volume of direct surface runoff for a given rainfall event. The performance of the SCS-CN method, based on large rainfall (P) and runoff (Q) datasets of United States watersheds, is evaluated using a large dataset of natural storm events from 27 agricultural plots in India. On the whole, the CN estimates from the National Engineering Handbook (chapter 4) tables do not match those derived from the observed P and Q datasets. As a result, the runoff prediction using former CNs was poor for the data of 22 (out of 24) plots. However, the match was little better for higher CN values, consistent with the general notion that the existing SCS-CN method performs better for high rainfall-runoff (high CN) events. Infiltration capacity (fc) was the main explanatory variable for runoff (or CN) production in study plots as it exhibited the expected inverse relationship between CN and fc. The plot-data optimization yielded initial abstraction coefficient (λ) values from 0 to 0.659 for the ordered dataset and 0 to 0.208 for the natural dataset (with 0 as the most frequent value). Mean and median λ values were, respectively, 0.030 and 0 for the natural rainfall-runoff dataset and 0.108 and 0 for the ordered rainfall-runoff dataset. Runoff estimation was very sensitive to λ and it improved consistently as λ changed from 0.2 to 0.03.

Leaf Pressure Volume Data in Caxiuana and Tapajos National Forest, Para, Brazil (2011)

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

Powell, Thomas; Moorcroft, Paul

Pressure volume curve measurements on leaves of canopy trees from the from the Caxiuana and Tapajos National Forests, Para, Brazil. Tapajos samples were harvested from the km 67 forested area, which is adjacent to the decommissioned throughfall exclusion drought experimental plot. Caxiuana samples were harvested from trees growing in the throughfall exclusion plots. Data were collected in 2011. Dataset includes: date of measurement, site ID, plot ID, tree ID (species, tree tag #), leaf area, fresh weight, relative weight, leaf water potential, and leaf water loss. P-V curve parameters (turgor loss point, osmotic potential, and bulk modulus of elasticity) canmore » be found in Powell et al. (2017) Differences in xylem cavitation resistance and leaf hydraulic traits explain differences in drought tolerance among mature Amazon rainforest trees. Global Change Biology.« less

The Los Alamos Gap Stick Test

NASA Astrophysics Data System (ADS)

Preston, Daniel; Hill, Larry; Johnson, Carl

2015-06-01

In this paper we describe a novel shock sensitivity test, the Gap Stick Test, which is a generalized variant of the ubiquitous Gap Test. Despite the popularity of the Gap Test, it has some disadvantages: multiple tests must be fired to obtain a single metric, and many tests must be fired to obtain its value to high precision and confidence. Our solution is a test wherein multiple gap tests are joined in series to form a rate stick. The complex re-initiation character of the traditional gap test is thereby retained, but the propagation speed is steady when measured at periodic intervals, and initiation delay in individual segments acts to decrement the average speed. We measure the shock arrival time before and after each inert gap, and compute the average detonation speed through the HE alone (discounting the gap thicknesses). We perform tests for a range of gap thicknesses. We then plot the aforementioned propagation speed as a function of gap thickness. The resulting curve has the same basic structure as a Diameter Effect (DE) curve, and (like the DE curve) terminates at a failure point. Comparison between experiment and hydrocode calculations using ALE3D and the Ignition and Growth reactive burn model calibrated for short duration shock inputs in PBX 9501 is discussed.

Comparison of three strong ion models used for quantifying the acid-base status of human plasma with special emphasis on the plasma weak acids.

PubMed

Anstey, Chris M

2005-06-01

Currently, three strong ion models exist for the determination of plasma pH. Mathematically, they vary in their treatment of weak acids, and this study was designed to determine whether any significant differences exist in the simulated performance of these models. The models were subjected to a "metabolic" stress either in the form of variable strong ion difference and fixed weak acid effect, or vice versa, and compared over the range 25 < or = Pco(2) < or = 135 Torr. The predictive equations for each model were iteratively solved for pH at each Pco(2) step, and the results were plotted as a series of log(Pco(2))-pH titration curves. The results were analyzed for linearity by using ordinary least squares regression and for collinearity by using correlation. In every case, the results revealed a linear relationship between log(Pco(2)) and pH over the range 6.8 < or = pH < or = 7.8, and no significant difference between the curve predictions under metabolic stress. The curves were statistically collinear. Ultimately, their clinical utility will be determined both by acceptance of the strong ion framework for describing acid-base physiology and by the ease of measurement of the independent model parameters.

Materials and Modulators for 3D Displays

DTIC Science & Technology

2002-08-01

1243 nm. 0, 180 and 360 deg. in this plot correspond to parallel polarization. The dashed curve is a cos2(θ) fit to the data with a constant value...dwell time (solid bold curve ), 10 µs dwell time (dashed bold curve ) and static case (thin dashed curve ). 26 Figure. 20. Schematics of free-space...photon. The two peaks in the two photon spectrum can be fit by two Lorentzian curves . These spectra indicate that in the rhodamine B molecule the

New Modelling of Localized Necking in Sheet Metal Stretching

NASA Astrophysics Data System (ADS)

Bressan, José Divo

2011-01-01

Present work examines a new mathematical model to predict the onset of localized necking in the industrial processes of sheet metal forming such as biaxial stretching. Sheet metal formability is usually assessed experimentally by testing such as the Nakajima test to obtain the Forming Limit Curve, FLC, which is an essential material parameter necessary to numerical simulations by FEM. The Forming Limit Diagram or "Forming Principal Strain Map" shows the experimental FLC which is the plot of principal true strains in the sheet metal surface, ɛ1 and ɛ2, occurring at critical points obtained in laboratory formability tests or in the fabrication process. Two types of undesirable rupture mechanisms can occur in sheet metal forming products: localized necking and shear induced fracture. Therefore, two kinds of limit strain curves can be plotted: the local necking limit curve FLC-N and the shear fracture limit curve FLC-S. Localized necking is theoretically anticipated to initiate at a thickness defect ƒin = hib/hia inside the grooved sheet thickness hia, but only at the instability point of maximum load. The inception of grooving on the sheet surface evolves from instability point to localized necking and final rupture, during further sheet metal straining. Work hardening law is defined for a strain and strain rate material by the effective stress σ¯ = σo(1+βɛ¯)n???ɛM. The average experimental hardening law curve for tensile tests at 0°, 45° and 90°, assuming isotropic plasticity, was used to analyze the plasticity behavior during the biaxial stretching of sheet metals. Theoretical predicted curves of local necking limits are plotted in the positive quadrant of FPSM for different defect values ƒin and plasticity parameters. Limit strains are obtained from a software developed by the author. Some experimental results of forming limit curve obtained from experiments for IF steel sheets are compared with the theoretical predicted curves: the correlation is good.

Recurrence Density Enhanced Complex Networks for Nonlinear Time Series Analysis

NASA Astrophysics Data System (ADS)

Costa, Diego G. De B.; Reis, Barbara M. Da F.; Zou, Yong; Quiles, Marcos G.; Macau, Elbert E. N.

We introduce a new method, which is entitled Recurrence Density Enhanced Complex Network (RDE-CN), to properly analyze nonlinear time series. Our method first transforms a recurrence plot into a figure of a reduced number of points yet preserving the main and fundamental recurrence properties of the original plot. This resulting figure is then reinterpreted as a complex network, which is further characterized by network statistical measures. We illustrate the computational power of RDE-CN approach by time series by both the logistic map and experimental fluid flows, which show that our method distinguishes different dynamics sufficiently well as the traditional recurrence analysis. Therefore, the proposed methodology characterizes the recurrence matrix adequately, while using a reduced set of points from the original recurrence plots.

Forest Health Monitoring in Maryland 1996-1999

Treesearch

Northeastern Research Station

2003-01-01

The National Forest Health Monitoring (FHM) program monitors the long-term status, changes and trends in the health of forest ecosystems and is conducted in cooperation with individual states. In Maryland, 40 FHM plots were established in 1991. Beginning in 1998, 95 plots were added. Each plot is a series of four fixed-area circular plots. Most tree measurements are...

Selections from 2017: Image Processing with AstroImageJ

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-12-01

Editors note:In these last two weeks of 2017, well be looking at a few selections that we havent yet discussed on AAS Nova from among the most-downloaded paperspublished in AAS journals this year. The usual posting schedule will resume in January.AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light CurvesPublished January2017The AIJ image display. A wide range of astronomy specific image display options and image analysis tools are available from the menus, quick access icons, and interactive histogram. [Collins et al. 2017]Main takeaway:AstroImageJ is a new integrated software package presented in a publication led byKaren Collins(Vanderbilt University,Fisk University, andUniversity of Louisville). Itenables new users even at the level of undergraduate student, high school student, or amateur astronomer to quickly start processing, modeling, and plotting astronomical image data.Why its interesting:Science doesnt just happen the momenta telescope captures a picture of a distantobject. Instead, astronomical images must firstbe carefully processed to clean up thedata, and this data must then be systematically analyzed to learn about the objects within it. AstroImageJ as a GUI-driven, easily installed, public-domain tool is a uniquelyaccessible tool for thisprocessing and analysis, allowing even non-specialist users to explore and visualizeastronomical data.Some features ofAstroImageJ:(as reported by Astrobites)Image calibration:generate master flat, dark, and bias framesImage arithmetic:combineimages viasubtraction, addition, division, multiplication, etc.Stack editing:easily perform operations on a series of imagesImage stabilization and image alignment featuresPrecise coordinate converters:calculate Heliocentric and Barycentric Julian DatesWCS coordinates:determine precisely where atelescope was pointed for an image by PlateSolving using Astronomy.netMacro and plugin support:write your own macrosMulti-aperture photometry with interactive light curve fitting:plot light curves of a star in real timeCitationKaren A. Collins et al 2017 AJ 153 77. doi:10.3847/1538-3881/153/2/77

Microwave Photonics

DTIC Science & Technology

2005-11-01

along X & Z The active area of the detector used is about 3 mm in diameter. Figure 54 shows two measured light power coupling curves plotted against...the scanned detector positions along the X & Z axes. At the top of the power curves , there are flat areas. It indicates that the detector collects...is about 400 m long for curve scanning along X direction and is about 500 m long for curve scanning along Z direction. This difference might be

Optical Variability Analysis of UU Aqr - an Eclipsing Nova-like System

NASA Astrophysics Data System (ADS)

Khruzina, T.; Katysheva, N.; Golysheva, P.; Shugarov, S.

2015-12-01

By using our photometric observations of nova-like system UU Aqr with unstable light curve during a few nights, we plotted phase-folded light curves and calculated a model of the system. We show that the complicated character of light curves can be explained by the spiral arms in the disk. We decomposed the syntesis photometric curve into separated components as accretion disk, white and red dwarf, hot line.

PRROC: computing and visualizing precision-recall and receiver operating characteristic curves in R.

PubMed

Grau, Jan; Grosse, Ivo; Keilwagen, Jens

2015-08-01

Precision-recall (PR) and receiver operating characteristic (ROC) curves are valuable measures of classifier performance. Here, we present the R-package PRROC, which allows for computing and visualizing both PR and ROC curves. In contrast to available R-packages, PRROC allows for computing PR and ROC curves and areas under these curves for soft-labeled data using a continuous interpolation between the points of PR curves. In addition, PRROC provides a generic plot function for generating publication-quality graphics of PR and ROC curves. © The Author 2015. Published by Oxford University Press.

Application of cross recurrence plot for identification of temperature fluctuations synchronization in parallel minichannels

NASA Astrophysics Data System (ADS)

Grzybowski, H.; Mosdorf, R.

2016-09-01

The temperature fluctuations occurring in flow boiling in parallel minichannels with diameter of 1 mm have been experimentally investigated and analysed. The wall temperature was recorded at each minichannel outlet by thermocouple with 0.08 mm diameter probe. The time series where recorded during dynamic two-phase flow instabilities which are accompanied by chaotic temperature fluctuations. Time series were denoised using wavelet decomposition and were analysed using cross recurrence plots (CRP) which enables the study of two time series synchronization.

An Approximate Solution and Master Curves for Buckling of Symmetrically Laminated Composite Cylinders

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.

2013-01-01

Nondimensional linear-bifurcation buckling equations for balanced, symmetrically laminated cylinders with negligible shell-wall anisotropies and subjected to uniform axial compression loads are presented. These equations are solved exactly for the practical case of simply supported ends. Nondimensional quantities are used to characterize the buckling behavior that consist of a stiffness-weighted length-to-radius parameter, a stiffness-weighted shell-thinness parameter, a shell-wall nonhomogeneity parameter, two orthotropy parameters, and a nondimensional buckling load. Ranges for the nondimensional parameters are established that encompass a wide range of laminated-wall constructions and numerous generic plots of nondimensional buckling load versus a stiffness-weighted length-to-radius ratio are presented for various combinations of the other parameters. These plots are expected to include many practical cases of interest to designers. Additionally, these plots show how the parameter values affect the distribution and size of the festoons forming each response curve and how they affect the attenuation of each response curve to the corresponding solution for an infinitely long cylinder. To aid in preliminary design studies, approximate formulas for the nondimensional buckling load are derived, and validated against the corresponding exact solution, that give the attenuated buckling response of an infinitely long cylinder in terms of the nondimensional parameters presented herein. A relatively small number of "master curves" are identified that give a nondimensional measure of the buckling load of an infinitely long cylinder as a function of the orthotropy and wall inhomogeneity parameters. These curves reduce greatly the complexity of the design-variable space as compared to representations that use dimensional quantities as design variables. As a result of their inherent simplicity, these master curves are anticipated to be useful in the ongoing development of buckling-design technology.

Newer developments on self-modeling curve resolution implementing equality and unimodality constraints.

PubMed

Beyramysoltan, Samira; Abdollahi, Hamid; Rajkó, Róbert

2014-05-27

Analytical self-modeling curve resolution (SMCR) methods resolve data sets to a range of feasible solutions using only non-negative constraints. The Lawton-Sylvestre method was the first direct method to analyze a two-component system. It was generalized as a Borgen plot for determining the feasible regions in three-component systems. It seems that a geometrical view is required for considering curve resolution methods, because the complicated (only algebraic) conceptions caused a stop in the general study of Borgen's work for 20 years. Rajkó and István revised and elucidated the principles of existing theory in SMCR methods and subsequently introduced computational geometry tools for developing an algorithm to draw Borgen plots in three-component systems. These developments are theoretical inventions and the formulations are not always able to be given in close form or regularized formalism, especially for geometric descriptions, that is why several algorithms should have been developed and provided for even the theoretical deductions and determinations. In this study, analytical SMCR methods are revised and described using simple concepts. The details of a drawing algorithm for a developmental type of Borgen plot are given. Additionally, for the first time in the literature, equality and unimodality constraints are successfully implemented in the Lawton-Sylvestre method. To this end, a new state-of-the-art procedure is proposed to impose equality constraint in Borgen plots. Two- and three-component HPLC-DAD data set were simulated and analyzed by the new analytical curve resolution methods with and without additional constraints. Detailed descriptions and explanations are given based on the obtained abstract spaces. Copyright © 2014 Elsevier B.V. All rights reserved.

Corrigendum to “Comparing activated alumina with indigenous laterite and bauxite as potential sorbents for removing fluoride from drinking water in Ghana” [Appl. Geochem. 56 (2015) 50–66

USGS Publications Warehouse

Craig, Laura; Stillings, Lisa; Decker, David L.; Thomas, James M.

2015-01-01

The authors regret that the application of the t-plot to determine the presence of micropores in the three sorbents needs the following corrections: (1) Fig. 1a, c, e are N2(g) adsorption and desorption isotherms” (remove “BET”). This correction applies to descriptions in the text as well. (2) Table 2, the column titled “Micropores” is mislabelled, and should be labelled “Film thickness”, which may not equal the pore width. The column titled “Micropore volume” is a correct description for laterite volume 0.0022 cm3 g−1 (t = 0.3–0.5 nm), but the other pore volumes listed cannot be identified as corresponding to micropores. They likely comprise both micropores and mesopores in laterite, while the presence of micropores in activated alumina is not clear. The positive y-intercept for the lowest linear portion of the laterite t-plot curve indicates micropores (Fig. 1f), and the shape of the t-plot curve suggests the presence of both micropores and mesopores. The shape of the activated alumina t-plot curve suggests the presence of micropores and mesopores, but the zero intercept for the lowest linear portion of the curve (Fig. 1b) creates uncertainty regarding the presence of micropores. Also see Storck et al., 1998; Hay et al. 2011 and references therein. (Additional note: analytical instrument Micromeritics® was misspelled as “Micrometrics”).The authors would like to apologise for any inconvenience caused.

A cost-benefit analysis of demand for food.

PubMed Central

Hursh, S R; Raslear, T G; Shurtleff, D; Bauman, R; Simmons, L

1988-01-01

Laboratory studies of consumer demand theory require assumptions regarding the definition of price in the absence of a medium of exchange (money). In this study we test the proposition that the fundamental dimension of price is a cost-benefit ratio expressed as the effort expended per unit of food value consumed. Using rats as subjects, we tested the generality of this "unit price" concept by varying four dimensions of price: fixed-ratio schedule, number of food pellets per fixed-ratio completion, probability of reinforcement, and response lever weight or effort. Two levels of the last three factors were combined in a 2 x 2 x 2 design giving eight groups. Each group was studied under a series of six FR schedules. Using the nominal values of all factors to determine unit price, we found that grams of food consumed plotted as a function of unit price followed a single demand curve. Similarly, total work output (responses x effort) conformed to a single function when plotted in terms of unit price. These observations provided a template for interpreting the effects of biological factors, such as brain lesions or drugs, that might alter the cost-benefit ratio. PMID:3209958

Modeling post-fire woody carbon dynamics with data from remeasured inventory plots

Treesearch

Bianca N.I. Eskelson; Jeremy Fried; Vicente Monleon

2015-01-01

In California, the Forest Inventory and Analysis (FIA) plots within large fires were visited one year after the fire occurred resulting in a time series of measurements before and after fire. During this additional plot visit, the standard inventory measurements were augmented for these burned plots to assess fire effects. One example of the additional measurements is...

Transforming Functions by Rescaling Axes

ERIC Educational Resources Information Center

Ferguson, Robert

2017-01-01

Students are often asked to plot a generalised parent function from their knowledge of a parent function. One approach is to sketch the parent function, choose a few points on the parent function curve, transform and plot these points, and use the transformed points as a guide to sketching the generalised parent function. Another approach is to…

Doppler interpretation of quasar red shifts.

PubMed

Zapolsky, H S

1966-08-05

The hypothesis that the quasistellar sources (quasars) are local objects moving with velocities close to the speed of light is examined. Provided there is no observational cutoff on apparent bolometric magnitude for the quasars, the transverse Doppler effect leads to the expectation of fewer blue shifts than red shifts for an isotropic distribution of velocities. Such a distribution also yields a function N(z), the number of objects with red shift less than z which is not inconsistent with the present data. On the basis of two extreme assumptions concerning the origin of such rapidly moving sources, we computed curves of red shift plotted against magnitude. In particular, the curve obtained on the assumption that the quasars originated from an explosion in or nearby our own galaxy is in as good agreement with the observations as the curve of cosmological red shift plotted against magnitude.

Analyzing Multiple-Choice Questions by Model Analysis and Item Response Curves

NASA Astrophysics Data System (ADS)

Wattanakasiwich, P.; Ananta, S.

2010-07-01

In physics education research, the main goal is to improve physics teaching so that most students understand physics conceptually and be able to apply concepts in solving problems. Therefore many multiple-choice instruments were developed to probe students' conceptual understanding in various topics. Two techniques including model analysis and item response curves were used to analyze students' responses from Force and Motion Conceptual Evaluation (FMCE). For this study FMCE data from more than 1000 students at Chiang Mai University were collected over the past three years. With model analysis, we can obtain students' alternative knowledge and the probabilities for students to use such knowledge in a range of equivalent contexts. The model analysis consists of two algorithms—concentration factor and model estimation. This paper only presents results from using the model estimation algorithm to obtain a model plot. The plot helps to identify a class model state whether it is in the misconception region or not. Item response curve (IRC) derived from item response theory is a plot between percentages of students selecting a particular choice versus their total score. Pros and cons of both techniques are compared and discussed.

A global map of rainfed cropland areas (GMRCA) at the end of last millennium using remote sensing

USGS Publications Warehouse

Biradar, C.M.; Thenkabail, P.S.; Noojipady, P.; Li, Y.; Dheeravath, V.; Turral, H.; Velpuri, M.; Gumma, M.K.; Gangalakunta, O.R.P.; Cai, X.L.; Xiao, X.; Schull, M.A.; Alankara, R.D.; Gunasinghe, S.; Mohideen, S.

2009-01-01

The overarching goal of this study was to produce a global map of rainfed cropland areas (GMRCA) and calculate country-by-country rainfed area statistics using remote sensing data. A suite of spatial datasets, methods and protocols for mapping GMRCA were described. These consist of: (a) data fusion and composition of multi-resolution time-series mega-file data-cube (MFDC), (b) image segmentation based on precipitation, temperature, and elevation zones, (c) spectral correlation similarity (SCS), (d) protocols for class identification and labeling through uses of SCS R2-values, bi-spectral plots, space-time spiral curves (ST-SCs), rich source of field-plot data, and zoom-in-views of Google Earth (GE), and (e) techniques for resolving mixed classes by decision tree algorithms, and spatial modeling. The outcome was a 9-class GMRCA from which country-by-country rainfed area statistics were computed for the end of the last millennium. The global rainfed cropland area estimate from the GMRCA 9-class map was 1.13 billion hectares (Bha). The total global cropland areas (rainfed plus irrigated) was 1.53 Bha which was close to national statistics compiled by FAOSTAT (1.51 Bha). The accuracies and errors of GMRCA were assessed using field-plot and Google Earth data points. The accuracy varied between 92 and 98% with kappa value of about 0.76, errors of omission of 2-8%, and the errors of commission of 19-36%. ?? 2008 Elsevier B.V.

Dynamical density delay maps: simple, new method for visualising the behaviour of complex systems

PubMed Central

2014-01-01

Background Physiologic signals, such as cardiac interbeat intervals, exhibit complex fluctuations. However, capturing important dynamical properties, including nonstationarities may not be feasible from conventional time series graphical representations. Methods We introduce a simple-to-implement visualisation method, termed dynamical density delay mapping (“D3-Map” technique) that provides an animated representation of a system’s dynamics. The method is based on a generalization of conventional two-dimensional (2D) Poincaré plots, which are scatter plots where each data point, x(n), in a time series is plotted against the adjacent one, x(n + 1). First, we divide the original time series, x(n) (n = 1,…, N), into a sequence of segments (windows). Next, for each segment, a three-dimensional (3D) Poincaré surface plot of x(n), x(n + 1), h[x(n),x(n + 1)] is generated, in which the third dimension, h, represents the relative frequency of occurrence of each (x(n),x(n + 1)) point. This 3D Poincaré surface is then chromatised by mapping the relative frequency h values onto a colour scheme. We also generate a colourised 2D contour plot from each time series segment using the same colourmap scheme as for the 3D Poincaré surface. Finally, the original time series graph, the colourised 3D Poincaré surface plot, and its projection as a colourised 2D contour map for each segment, are animated to create the full “D3-Map.” Results We first exemplify the D3-Map method using the cardiac interbeat interval time series from a healthy subject during sleeping hours. The animations uncover complex dynamical changes, such as transitions between states, and the relative amount of time the system spends in each state. We also illustrate the utility of the method in detecting hidden temporal patterns in the heart rate dynamics of a patient with atrial fibrillation. The videos, as well as the source code, are made publicly available. Conclusions Animations based on density delay maps provide a new way of visualising dynamical properties of complex systems not apparent in time series graphs or standard Poincaré plot representations. Trainees in a variety of fields may find the animations useful as illustrations of fundamental but challenging concepts, such as nonstationarity and multistability. For investigators, the method may facilitate data exploration. PMID:24438439

The average receiver operating characteristic curve in multireader multicase imaging studies

PubMed Central

Samuelson, F W

2014-01-01

Objective: In multireader, multicase (MRMC) receiver operating characteristic (ROC) studies for evaluating medical imaging systems, the area under the ROC curve (AUC) is often used as a summary metric. Owing to the limitations of AUC, plotting the average ROC curve to accompany the rigorous statistical inference on AUC is recommended. The objective of this article is to investigate methods for generating the average ROC curve from ROC curves of individual readers. Methods: We present both a non-parametric method and a parametric method for averaging ROC curves that produce a ROC curve, the area under which is equal to the average AUC of individual readers (a property we call area preserving). We use hypothetical examples, simulated data and a real-world imaging data set to illustrate these methods and their properties. Results: We show that our proposed methods are area preserving. We also show that the method of averaging the ROC parameters, either the conventional bi-normal parameters (a, b) or the proper bi-normal parameters (c, da), is generally not area preserving and may produce a ROC curve that is intuitively not an average of multiple curves. Conclusion: Our proposed methods are useful for making plots of average ROC curves in MRMC studies as a companion to the rigorous statistical inference on the AUC end point. The software implementing these methods is freely available from the authors. Advances in knowledge: Methods for generating the average ROC curve in MRMC ROC studies are formally investigated. The area-preserving criterion we defined is useful to evaluate such methods. PMID:24884728

Influence of lidar, Landsat imagery, disturbance history, plot location accuracy, and plot size on accuracy of imputation maps of forest composition and structure

Treesearch

Harold S.J. Zald; Janet L. Ohmann; Heather M. Roberts; Matthew J. Gregory; Emilie B. Henderson; Robert J. McGaughey; Justin Braaten

2014-01-01

This study investigated how lidar-derived vegetation indices, disturbance history from Landsat time series (LTS) imagery, plot location accuracy, and plot size influenced accuracy of statistical spatial models (nearest-neighbor imputation maps) of forest vegetation composition and structure. Nearest-neighbor (NN) imputation maps were developed for 539,000 ha in the...

Integrating field plots, lidar, and landsat time series to provide temporally consistent annual estimates of biomass from 1990 to present

Treesearch

Warren B. Cohen; Hans-Erik Andersen; Sean P. Healey; Gretchen G. Moisen; Todd A. Schroeder; Christopher W. Woodall; Grant M. Domke; Zhiqiang Yang; Robert E. Kennedy; Stephen V. Stehman; Curtis Woodcock; Jim Vogelmann; Zhe Zhu; Chengquan Huang

2015-01-01

We are developing a system that provides temporally consistent biomass estimates for national greenhouse gas inventory reporting to the United Nations Framework Convention on Climate Change. Our model-assisted estimation framework relies on remote sensing to scale from plot measurements to lidar strip samples, to Landsat time series-based maps. As a demonstration, new...

Reversible susceptibility studies of magnetization switching in FeCoB synthetic antiferromagnets

NASA Astrophysics Data System (ADS)

Radu, Cosmin; Cimpoesu, Dorin; Girt, Erol; Ju, Ganping; Stancu, Alexandru; Spinu, Leonard

2007-05-01

In this paper we present a study of switching characteristics of a series of synthetic antiferromagnet (SAF) structures using reversible susceptibility experiments. Three series of SAF samples were considered in our study with (t1, t2), the thickness of the FeCoB layers of (80nm, 80nm), (50nm, 50nm), and (80nm, 20nm) and with the interlayer of Ru ranging from 0to2nm. A vector vibrating sample magnetometer was used to measure the hysteresis loops along the different directions in the plane of the samples. The reversible susceptibility experiments were performed using a resonant method based on a tunnel diode oscillator. We showed that the switching peaks in the susceptibility versus field plots obtained for different orientations of the applied dc field can be used to construct the switching diagram of the SAF structure. The critical curve constitutes the fingerprint of the switching behavior and provides information about micromagnetic and structural properties of SAF which is an essential component of modern magnetic random access memories.

Variations in height-over-age curves for young longleaf pine plantations

Treesearch

William D. Boyer

1983-01-01

Abstract.Some environmental factors related to height growth of longleaf pine (Pinus palustris Mill.) plantations were identified by analyses of data from remeasured plots. A total of 660 plots, mostly from the Southwide Pine Seed Source Study, provided 2,737 height-over-age observations from age 3 through ages 15 or 20 to 22. A...

Analysis of growth trend changes for 51 temperate tree species using Korea national forest inventory data

NASA Astrophysics Data System (ADS)

Park, M.; Moon, M.; Park, J.; Cho, S.; Kim, H. S.

2016-12-01

Individual tree growth rates can be affected by various factors such as species, soil fertility, stand development stage, disturbance, and climate etc. To estimate the effect of changes in tree growth rate on the structure and functionality of forest ecosystem in the future, we analyzed the change of species-specific growth trends using the fifth Korea national forest inventory data, which was collected from 2006 to 2010. The ring samples of average tree were collected from nationwide inventory plots and the total number of individual tree ring series was 69,128 covering 185 tree species. Among those, fifty one species with more than 100 tree ring series were used for our analysis. For growth-trend analysis, standardized regional curves of individual species growth were generated from three forest zone in South Korea; subarctic, cool temperate, warm temperate forest zone. Then individual tree ring series was indexed by dividing the growth of the tree by expected growth from standardized regional curves. Then the ratio of all tree ring series were aligned by year and the Spearman's correlation coefficient of each species was calculated. The results show that most of species had increasing growth rates as forests developed after Korean war. For the last thirty years, 67.3% of species including Quercus spp. and Zelkova serrata had positive growth trends, on the other hand, 11.5% of species including Pinus spp. showed negative growth trends probably due to the changes in successional stages in Korean forests and climate change. These trends also vary with climate zone and species. For examples, Pinus densiflora, which showed negative growth trend overall, had steep negative growth trends in boreal and temperate zone, whereas it showed no specific trend in sub-tropical climate zone. Our trend analysis on 51 temperate tree species growth will be essential to predict the temperate forests species change for the this century.

A Software Tool for the Rapid Analysis of the Sintering Behavior of Particulate Bodies

DTIC Science & Technology

2017-11-01

bounded by a region that the user selects via cross hairs . Future plot analysis features, such as more complicated curve fitting and modeling functions...German RM. Grain growth behavior of tungsten heavy alloys based on the master sintering curve concept. Metallurgical and Materials Transactions A

Volcano plots in analyzing differential expressions with mRNA microarrays.

PubMed

Li, Wentian

2012-12-01

A volcano plot displays unstandardized signal (e.g. log-fold-change) against noise-adjusted/standardized signal (e.g. t-statistic or -log(10)(p-value) from the t-test). We review the basic and interactive use of the volcano plot and its crucial role in understanding the regularized t-statistic. The joint filtering gene selection criterion based on regularized statistics has a curved discriminant line in the volcano plot, as compared to the two perpendicular lines for the "double filtering" criterion. This review attempts to provide a unifying framework for discussions on alternative measures of differential expression, improved methods for estimating variance, and visual display of a microarray analysis result. We also discuss the possibility of applying volcano plots to other fields beyond microarray.

Growth Charts for Prader-Willi Syndrome During Growth Hormone Treatment

PubMed Central

Butler, Merlin G.; Lee, Jaehoon; Cox, Devin M.; Manzardo, Ann M.; Gold, June-Anne; Miller, Jennifer L.; Roof, Elizabeth; Dykens, Elisabeth; Kimonis, Virginia; Driscoll, Daniel J.

2018-01-01

The purpose of the current study was to develop syndrome-specific standardized growth curves for growth hormone–treated Prader-Willi syndrome (PWS) individuals aged 0 to 18 years. Anthropometric growth-related measures were obtained on 171 subjects with PWS who were treated with growth hormone for at least 40% of their lifespan. They had no history of scoliosis. PWS standardized growth curves were developed for 7 percentile ranges using the LMS method for weight, height, head circumference, weight/length, and BMI along with normative 3rd, 50th, and 97th percentiles plotted using control data from the literature and growth databases. Percentiles were plotted on growth charts for comparison purposes. Growth hormone treatment appears to normalize stature and markedly improves weight in PWS compared with standardized curves for non–growth hormone–treated PWS individuals. Growth chart implications and recommended usage are discussed. PMID:26842920

Fuzzy recurrence plots

NASA Astrophysics Data System (ADS)

Pham, T. D.

2016-12-01

Recurrence plots display binary texture of time series from dynamical systems with single dots and line structures. Using fuzzy recurrence plots, recurrences of the phase-space states can be visualized as grayscale texture, which is more informative for pattern analysis. The proposed method replaces the crucial similarity threshold required by symmetrical recurrence plots with the number of cluster centers, where the estimate of the latter parameter is less critical than the estimate of the former.

NUTRITIONAL STUDIES ON THE CONFUSED FLOUR BEETLE, TRIBOLIUM CONFUSUM DUVAL

PubMed Central

Chapman, Royal N.

1924-01-01

The confused flour beetle (Tribolium confusum) was chosen for this study because it lives in a food which ordinarily contains no living organisms. The death rates are greater in cultures which are handled daily than in those which are not handled but when all are handled alike the results are comparable. The results from experiments with individual beetles in various kinds of flour were plotted with instars (larval stages) on the ordinate and time in days on the abscissa, using the results from control experiments in wheat flour to determine the length of the various instars from an "x = y" formula. The curves of development were found to be straight lines throughout all but the last instar. The curve for the last instar during which the larva transformed deviated from the straight line in certain foods, notably rice flour. When mass cultures were used the death and transformation curves were plotted for each synthetic food. A comparison of the curves from wheat flour and the synthetic foods shows that the first parts of the curves are very much alike in all cases and that a few resemble the control in every respect except that the transformation curve has been moved back for a considerable time. The death curves for the mass cultures are not smooth but show sudden increase in death at approximately the times of molting. These curves may therefore be compared with the records from individual beetles. PMID:19872096

Application of the compensated Arrhenius formalism to self-diffusion: implications for ionic conductivity and dielectric relaxation.

PubMed

Petrowsky, Matt; Frech, Roger

2010-07-08

Self-diffusion coefficients are measured from -5 to 80 degrees C in a series of linear alcohols using pulsed field gradient NMR. The temperature dependence of these data is studied using a compensated Arrhenius formalism that assumes an Arrhenius-like expression for the diffusion coefficient; however, this expression includes a dielectric constant dependence in the exponential prefactor. Scaling temperature-dependent diffusion coefficients to isothermal diffusion coefficients so that the exponential prefactors cancel results in calculated energies of activation E(a). The exponential prefactor is determined by dividing the temperature-dependent diffusion coefficients by the Boltzmann term exp(-E(a)/RT). Plotting the prefactors versus the dielectric constant places the data on a single master curve. This procedure is identical to that previously used to study the temperature dependence of ionic conductivities and dielectric relaxation rate constants. The energies of activation determined from self-diffusion coefficients in the series of alcohols are strikingly similar to those calculated for the same series of alcohols from both dielectric relaxation rate constants and ionic conductivities of dilute electrolytes. The experimental results are described in terms of an activated transport mechanism that is mediated by relaxation of the solution molecules. This microscopic picture of transport is postulated to be common to diffusion, dielectric relaxation, and ionic transport.

[A study of Ververck index in 16 865 singleton neonates with a gestational age of 27-42 weeks in Shenzhen, China].

PubMed

Huang, Xiao-Yun; Liu, Hui-Long; Lei, Min; Lian, Zhao-Hui; Mai, Hui-Fen

2018-01-01

Ververck index (VI) reflects thoracic development, body type, and nutritional status. This study aimed to investigate the VI of singleton neonates with a gestational age (GA) of 27-42 weeks at birth, and to establish percentile curves of VI of the neonates. Cross-sectional cluster sampling was performed between April 2013 and September 2015. Body weight, body length, and chest circumference were measured for 16 865 singleton neonates with a GA of 27-42 weeks in two hospitals in Shenzhen, China. VI was calculated and the percentile curves of VI were plotted for the neonates. Mean VIs were obtained for singleton neonates with a gestational age of 27-42 weeks (in three groups of male, female, and both sexes), and related 3rd-97th percentile curves were plotted. As for the 50th percentile curve, the singleton neonates with a GA of 27 weeks had the lowest 50th percentile value of VI, which gradually increased with the increase in GA. The singleton neonates with a GA of 42 weeks had the highest 50th percentile value of VI. Girls had a slightly higher 50th percentile value of VI than boys in all GA groups. VI of neonates increases with the increase in GA. Female neonates may have a slightly better thoracic development, body type, and nutritional status than male neonates at birth. The percentile curves of VI plotted for singleton neonates with a GA of 27-42 weeks (in three groups of male, female, and both sexes) can provide a basis for evaluating thoracic development, body type, and nutritional status of neonates at birth in Shenzhen, China.

Students' Challenges with Polar Functions: Covariational Reasoning and Plotting in the Polar Coordinate System

ERIC Educational Resources Information Center

Habre, Samer

2017-01-01

Covariational reasoning has been the focus of many studies but only a few looked into this reasoning in the polar coordinate system. In fact, research on student's familiarity with polar coordinates and graphing in the polar coordinate system is scarce. This paper examines the challenges that students face when plotting polar curves using the…

Site Index Curves for Direct-Seeded Loblolly and Longleaf Pines in Louisiana

Treesearch

Quang V. Cao; V. Clark Baldwin; Richard E. Lohrey

1995-01-01

Site index equations were developed for direct-seeded loblollypine (Pinus taeda L.) and longleaf pine (Pinus palustris Mill.) based on data from 148 and 75 permanent plots, respectively. These plots varied from 0.053 to 0.119 ac in size, and were established in broadcast, row, and spot seeded stands throughout Louisiana. The Bailey and Clutter (1974) model was...

Use of the densiometer to estimate density of forest canopy on permanent sample plots.

Treesearch

Gerald S. Strickler

1959-01-01

An instrument known as the spherical densiometer has been found adaptable to permanent-plot estimates of relative canopy closure or density in forest and range ecological studies. The device is more compact and simpler to use than previous ocular-type instruments. Because the instrument has a curved reflecting surface which results in observations from lateral as well...

Graphical tests for Hardy-Weinberg equilibrium based on the ternary plot.

PubMed

Graffelman, Jan; Camarena, Jair Morales

2008-01-01

We design a graphical test for Hardy-Weinberg equilibrium. This can circumvent the calculation of p values and the statistical (non)significance of a large number of bi-allelic markers can be inferred from their position in a graph. By rewriting expressions for the chi(2) statistic (with and without continuity correction) in terms of the heterozygote frequency an acceptance region for Hardy-Weinberg equilibrium is obtained that can be depicted in a ternary plot. We obtain equations for curves in the ternary plot that separate markers that are out of Hardy-Weinberg equilibrium from those that are in equilibrium. The curves depend on the chosen significance level, the sample size and on a continuity correction parameter. Some examples of graphical tests using a set of 106 SNPs on the long arm of human chromosome 22 are described. Significant markers and poor markers with a lot of missing values are easily identified in the proposed plots. R software for making the diagrams is provided. The proposed graphs can be used as control charts for spotting problematic markers in large scale genotyping studies, and constitute an excellent tool for the graphical exploration of bi-allelic marker data. (c) 2007 S. Karger AG, Basel.

Mass Distributions Implying Flat Galactic Rotation Curves

ERIC Educational Resources Information Center

Keeports, David

2010-01-01

The rotational speeds of stars in the disc of a spiral galaxy are virtually independent of the distances of the stars from the centre of the galaxy. In common parlance, the stellar speed versus distance plot known as a galactic rotation curve is by observation typically nearly flat. This observation provides strong evidence that most galactic…

System and method for constructing filters for detecting signals whose frequency content varies with time

DOEpatents

Qian, Shie; Dunham, Mark E.

1996-01-01

A system and method for constructing a bank of filters which detect the presence of signals whose frequency content varies with time. The present invention includes a novel system and method for developing one or more time templates designed to match the received signals of interest and the bank of matched filters use the one or more time templates to detect the received signals. Each matched filter compares the received signal x(t) with a respective, unique time template that has been designed to approximate a form of the signals of interest. The robust time domain template is assumed to be of the order of w(t)=A(t)cos{2.pi..phi.(t)} and the present invention uses the trajectory of a joint time-frequency representation of x(t) as an approximation of the instantaneous frequency function {.phi.'(t). First, numerous data samples of the received signal x(t) are collected. A joint time frequency representation is then applied to represent the signal, preferably using the time frequency distribution series (also known as the Gabor spectrogram). The joint time-frequency transformation represents the analyzed signal energy at time t and frequency .function., P(t,f), which is a three-dimensional plot of time vs. frequency vs. signal energy. Then P(t,f) is reduced to a multivalued function f(t), a two dimensional plot of time vs. frequency, using a thresholding process. Curve fitting steps are then performed on the time/frequency plot, preferably using Levenberg-Marquardt curve fitting techniques, to derive a general instantaneous frequency function .phi.'(t) which best fits the multivalued function f(t), a trajectory of the joint time-frequency domain representation of x(t). Integrating .phi.'(t) along t yields .phi.(t), which is then inserted into the form of the time template equation. A suitable amplitude A(t) is also preferably determined. Once the time template has been determined, one or more filters are developed which each use a version or form of the time template.

Preliminary stage-discharge relations for Tombigbee River at Aliceville lock and dam, near Pickensville, Alabama

USGS Publications Warehouse

Nelson, G.H.; Ming, C.O.

1983-01-01

The construction of Aliceville lock and dam and other related channel alterations, completed in 1979, has resulted in changes to the stage-discharge relations in the vicinity. The scarcity of current-meter measurements, coupled with backwater conditions, makes definition of a single stage-discharge relation impossible. However, limit curves can be defined that would encompass such a relation. Backwater is defined as water backed up or retarded in its course as compared with water flowing under normal or natural conditions. This results in a rise in stage above normal water level while the discharge remains unaffected. Backwater is usually caused by temporary obstruction(s) to flow downstream. Backwater at Aliceville Dam results from a variety of river conditions. Some of these conditions are large tributary inflow, return of flood plain flows to the main channel during recessions, and operations at Gainesville Dam during low flows. The discharges obtained from 26 current-meter measurements, along with computed discharges through the dam, are plotted versus stage. The plot illustrates, by the scatter of data points, the variations in backwater. Curves are drawn to envelope the extreme plot patterns showing possible ranges of several feet in stage for any given discharge. The upper end of the curves were extrapolated based on the results of a step-backwater analysis.

SNaX: A Database of Supernova X-Ray Light Curves

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

Ross, Mathias; Dwarkadas, Vikram V., E-mail: Mathias_Ross@msn.com, E-mail: vikram@oddjob.uchicago.edu

We present the Supernova X-ray Database (SNaX), a compilation of the X-ray data from young supernovae (SNe). The database includes the X-ray fluxes and luminosities of young SNe, from days to years after outburst. The original goal and intent of this study was to present a database of Type IIn SNe (SNe IIn), which we have accomplished. Our ongoing goal is to expand the database to include all SNe for which published data are available. The database interface allows one to search for SNe using various criteria, plot all or selected data points, and download both the data and themore » plot. The plotting facility allows for significant customization. There is also a facility for the user to submit data that can be directly incorporated into the database. We include an option to fit the decay of any given SN light curve with a power-law. The database includes a conversion of most data points to a common 0.3–8 keV band so that SN light curves may be directly compared with each other. A mailing list has been set up to disseminate information about the database. We outline the structure and function of the database, describe its various features, and outline the plans for future expansion.« less

A new improved graphical and quantitative method for detecting bias in meta-analysis.

PubMed

Furuya-Kanamori, Luis; Barendregt, Jan J; Doi, Suhail A R

2018-04-04

Detection of publication and related biases remains suboptimal and threatens the validity and interpretation of meta-analytical findings. When bias is present, it usually differentially affects small and large studies manifesting as an association between precision and effect size and therefore visual asymmetry of conventional funnel plots. This asymmetry can be quantified and Egger's regression is, by far, the most widely used statistical measure for quantifying funnel plot asymmetry. However, concerns have been raised about both the visual appearance of funnel plots and the sensitivity of Egger's regression to detect such asymmetry, particularly when the number of studies is small. In this article, we propose a new graphical method, the Doi plot, to visualize asymmetry and also a new measure, the LFK index, to detect and quantify asymmetry of study effects in Doi plots. We demonstrate that the visual representation of asymmetry was better for the Doi plot when compared with the funnel plot. We also show that the diagnostic accuracy of the LFK index in discriminating between asymmetry due to simulated publication bias versus chance or no asymmetry was also better with the LFK index which had areas under the receiver operating characteristic curve of 0.74-0.88 with simulations of meta-analyses with five, 10, 15, and 20 studies. The Egger's regression result had lower areas under the receiver operating characteristic curve values of 0.58-0.75 across the same simulations. The LFK index also had a higher sensitivity (71.3-72.1%) than the Egger's regression result (18.5-43.0%). We conclude that the methods proposed in this article can markedly improve the ability of researchers to detect bias in meta-analysis.

Study on Energy Absorption Capacity of Steel-Polyester Hybrid Fiber Reinforced Concrete Under Uni-axial Compression

NASA Astrophysics Data System (ADS)

Chella Gifta, C.; Prabavathy, S.

2018-05-01

This work presents the energy absorption capacity of hybrid fiber reinforced concrete made with hooked end steel fibers (0.5 and 0.75%) and straight polyester fibers (0.5, 0.8, 1.0 and 2.0%). Compressive toughness (energy absorption capacity) under uni-axial compression was evaluated on 100 × 200 mm size cylindrical specimens with varying steel and polyester fiber content. Efficiency of the hybrid fiber reinforcement is studied with respect to fiber type, size and volume fractions in this investigation. The vertical displacement under uni-axial compression was measured under the applied loads and the load-deformation curves were plotted. From these curves the toughness values were calculated and the results were compared with steel and polyester as individual fibers. The hybridization of 0.5% steel + 0.5% polyester performed well in post peak region due to the addition of polyester fibers with steel fibers and the energy absorption value was 23% greater than 0.5% steel FRC. Peak stress values were also higher in hybrid series than single fiber and based on the results it is concluded that hybrid fiber reinforcement improves the toughness characteristics of concrete without affecting workability.

Mixed convection peristaltic motion of copper-water nanomaterial with velocity slip effects in a curved channel.

PubMed

Hayat, T; Farooq, S; Alsaedi, A

2017-04-01

The primary objective of present analysis is to model the peristalsis of copper-water based nanoliquid in the presence of first order velocity and thermal slip conditions in a curved channel. Mixed convection, viscous dissipation and heat generation/absorption are also accounted. Mathematical formulation is simplified under the assumption of small Reynolds number and large wavelength. Regular perturbation technique is employed to find the solution of the resulting equations in terms of series for small Brinkman number. The final expression for pressure gradient, pressure rise, stream function, velocity and temperature are obtained and discussed through graphs. Mathematica software is utilized to compute the solution of the system of equations and to plot the graphical results. Results indicates that insertion of 30% copper nanoparticles in the basefluid (water) velocity and temperature reduces by almost 3% and 40% respecively. Moreover it is seen that size of the trapped bolus also reduces almost 20% with the insertion of 20% nanoparticles (copper) in the basefluid (water). It is noted that velocity and temperature are decreasing functions of nanoparticle volume fraction. Moreover the temperature rises when heat generation parameter and Brinkman number are enhanced. Copyright © 2017 Elsevier B.V. All rights reserved.

A critical evaluation of theories for predicting microcracking in composite laminates

NASA Technical Reports Server (NTRS)

Nairn, John A.; Hu, Shoufeng; Bark, Jong S.

1993-01-01

We present experimental results on 21 different layups of Hercules AS4 carbon fiber/3501-6 epoxy laminates. All laminates had 90 deg plies; some had them in the middle, while some had them on a free surface. During tensile loading, the first form of damage in all laminates was microcracking of the 90 deg plies. For each laminate, we recorded both the crack density and the complete distribution of crack spacings as a function of the applied load. By rearranging various microcracking theories, we developed a master-curve approach that permitted plotting the results from all laminates on a single plot. By comparing master-curve plots for different theories, it was possible to critically evaluate the quality of those theories. We found that a critical-energy-release-rate criterion calculated using a 2D variational stress analysis gave the best results. All microcracking theories based on a strength-failure criteria gave poor results. All microcracking theories using 1D stress analyses, regardless of the failure criterion, also gave poor results.

Effect of support flexibilty and damping on the dynamic response of a single mass flexible rotor in elastic bearings

NASA Technical Reports Server (NTRS)

Kirk, R. G.; Gunter, E. J.

1972-01-01

A steady state analysis of the shaft and the bearing housing motion was made by assuming synchronous precession of the system. The conditions under which the support system would act as a dynamic vibration absorber at the rotor critical speed were studied; plots of the rotor and support amplitudes, phase angles, and forces transmitted were evaluated by the computer, and the performance curves were automatically plotted by a CalComp plotter unit. Curves are presented on the optimization of the support housing characteristics to attenuate the rotor unbalance response over the entire rotor speed range. The complete transient motion including rotor unbalance was examined by integrating the equations of motion numerically using a modified fourth order Runge-Kutta procedure, and the resulting whirl orbits were plotted by the CalComp plotter unit. The results of the transient analysis are discussed with regards to the design optimization procedure derived from the steady-state analysis.

Model-independent plot of dynamic PET data facilitates data interpretation and model selection.

PubMed

Munk, Ole Lajord

2012-02-21

When testing new PET radiotracers or new applications of existing tracers, the blood-tissue exchange and the metabolism need to be examined. However, conventional plots of measured time-activity curves from dynamic PET do not reveal the inherent kinetic information. A novel model-independent volume-influx plot (vi-plot) was developed and validated. The new vi-plot shows the time course of the instantaneous distribution volume and the instantaneous influx rate. The vi-plot visualises physiological information that facilitates model selection and it reveals when a quasi-steady state is reached, which is a prerequisite for the use of the graphical analyses by Logan and Gjedde-Patlak. Both axes of the vi-plot have direct physiological interpretation, and the plot shows kinetic parameter in close agreement with estimates obtained by non-linear kinetic modelling. The vi-plot is equally useful for analyses of PET data based on a plasma input function or a reference region input function. The vi-plot is a model-independent and informative plot for data exploration that facilitates the selection of an appropriate method for data analysis. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Designs of Fins Air-Cooled Cylinders

DTIC Science & Technology

1939-06-28

4 (a). EMer part of figure 4 clearly shows that, for one pnir of values of s and t, the heat transfer is a maximum. The peak values of the curves of...specified s” curves. Similarly, the peak values of the curves of constant values of t shown in &ure 4 (b) and of similar cwwes plotted for othm values of... picking the values of optimum g and t from these curves: PIots of tk type shown in figure 4 were obtained for - other \\ralues of M and Aplpa,/m by means

Growth curve for Propionibacterium acnes.

PubMed

Hall, G S; Pratt-Rippin, K; Meisler, D M; Washington, J A; Roussel, T J; Miller, D

1994-06-01

We established growth curves for Propionibacterium acnes isolates recovered from eyes with chronic postoperative endophthalmitis. The growth curve plotted the average of the duplicate bacterial concentration against time. The generation time for P. acnes calculated from the growth curves was approximately 5.1 hours. The growth of P. acnes is slower than other anaerobic bacteria. This may account for its delayed appearance in culture of ocular specimens. It may also explain treatment failure if the concentration of an antibiotic injected into the vitreous does not remain at an effective level during the critical replicative phase of the organism.

Visual search for tropical web spiders: the influence of plot length, sampling effort, and phase of the day on species richness.

PubMed

Pinto-Leite, C M; Rocha, P L B

2012-12-01

Empirical studies using visual search methods to investigate spider communities were conducted with different sampling protocols, including a variety of plot sizes, sampling efforts, and diurnal periods for sampling. We sampled 11 plots ranging in size from 5 by 10 m to 5 by 60 m. In each plot, we computed the total number of species detected every 10 min during 1 hr during the daytime and during the nighttime (0630 hours to 1100 hours, both a.m. and p.m.). We measured the influence of time effort on the measurement of species richness by comparing the curves produced by sample-based rarefaction and species richness estimation (first-order jackknife). We used a general linear model with repeated measures to assess whether the phase of the day during which sampling occurred and the differences in the plot lengths influenced the number of species observed and the number of species estimated. To measure the differences in species composition between the phases of the day, we used a multiresponse permutation procedure and a graphical representation based on nonmetric multidimensional scaling. After 50 min of sampling, we noted a decreased rate of species accumulation and a tendency of the estimated richness curves to reach an asymptote. We did not detect an effect of plot size on the number of species sampled. However, differences in observed species richness and species composition were found between phases of the day. Based on these results, we propose guidelines for visual search for tropical web spiders.

Recurrence plots revisited

NASA Astrophysics Data System (ADS)

Casdagli, M. C.

1997-09-01

We show that recurrence plots (RPs) give detailed characterizations of time series generated by dynamical systems driven by slowly varying external forces. For deterministic systems we show that RPs of the time series can be used to reconstruct the RP of the driving force if it varies sufficiently slowly. If the driving force is one-dimensional, its functional form can then be inferred up to an invertible coordinate transformation. The same results hold for stochastic systems if the RP of the time series is suitably averaged and transformed. These results are used to investigate the nonlinear prediction of time series generated by dynamical systems driven by slowly varying external forces. We also consider the problem of detecting a small change in the driving force, and propose a surrogate data technique for assessing statistical significance. Numerically simulated time series and a time series of respiration rates recorded from a subject with sleep apnea are used as illustrative examples.

[Use of bivariate survival curves for analyzing mortality of heart failure and sudden death in dilated cardiomiopathy].

PubMed

Gregori, Dario; Rosato, Rosalba; Zecchin, Massimo; Di Lenarda, Andrea

2005-01-01

This paper discusses the use of bivariate survival curves estimators within the competing risk framework. Competing risks models are used for the analysis of medical data with more than one cause of death. The case of dilated cardiomiopathy is explored. Bivariate survival curves plot the conjoint mortality processes. The different graphic representation of bivariate survival analysis is the major contribute of this methodology to the competing risks analysis.

Electrophoresis of DNA in agarose gels, polyacrylamide gels and in free solution

PubMed Central

Stellwagen, Nancy C.

2009-01-01

This review describes the electrophoresis of curved and normal DNA molecules in agarose gels, polyacrylamide gels and in free solution. These studies were undertaken to clarify why curved DNA molecules migrate anomalously slowly in polyacrylamide gels but not in agarose gels. Two milestone papers are cited, in which Ferguson plots were used to estimate the effective pore size of agarose and polyacrylamide gels. Subsequent studies on the effect of the electric field on agarose and polyacrylamide gel matrices, DNA interactions with the two gel matrices, and the effect of curvature on the free solution mobility of DNA are also described. The combined results suggest that the anomalously slow mobilities observed for curved DNA molecules in polyacrylamide gels are due primarily to preferential interactions of curved DNAs with the polyacrylamide gel matrix; the restrictive pore size of the matrix is of lesser importance. In free solution, DNA mobilities increase with increasing molecular mass until leveling off at a plateau value of (3.17 ± 0.01) × 10-4 cm2/Vs in 40 mM Tris-acetate-EDTA buffer at 20°C. Curved DNA molecules migrate anomalously slowly in free solution as well as in polyacrylamide gels, explaining why the Ferguson plots of curved and normal DNAs containing the same number of base pairs extrapolate to different mobilities at zero gel concentration. PMID:19517510

Shallow Water Propagation

DTIC Science & Technology

2010-02-26

bottom waveguide. The lower contour plot demonstrates that this method, unlike other parabolic equations, can treat seismic sources. 20100308162...solitons. One illustration in Figure 8 shows depth-averaged data at the Naval Research Laboratory vertical line array (VLA) [dashed blue curves...vertical line array about 15 km from the source. The right panel [blue curves] compares corresponding simulations from a three-dimensional adiabatic mode

Computational Tools for Probing Interactions in Multiple Linear Regression, Multilevel Modeling, and Latent Curve Analysis

ERIC Educational Resources Information Center

Preacher, Kristopher J.; Curran, Patrick J.; Bauer, Daniel J.

2006-01-01

Simple slopes, regions of significance, and confidence bands are commonly used to evaluate interactions in multiple linear regression (MLR) models, and the use of these techniques has recently been extended to multilevel or hierarchical linear modeling (HLM) and latent curve analysis (LCA). However, conducting these tests and plotting the…

The effect of support flexibility and damping on the dynamic response of a single mass flexible rotor in elastic bearings

NASA Technical Reports Server (NTRS)

Kirk, R. G.; Gunter, E. J.

1972-01-01

The dynamic unabalance response and transient motion of the single mass Jeffcott rotor in elastic bearings mounted on damped, flexible supports are discussed. A steady state analysis of the shaft and the bearing housing motion was made by assuming synchronous precession of the system. The conditions under which the support system would act as a dynamic vibration absorber at the rotor critical speed were studied. Plots of the rotor and support amplitudes, phase angles, and forces transmitted were evaluated by the computer and the performance curves were plotted by an automatic plotter unit. Curves are presented on the optimization of the support housing characteristics of attenuate the rotor synchronous unbalance response.

[Penis growth and development in children and adolescents: a study based on GAMLSS].

PubMed

Yi, Qing-Jie; Zeng, Yan; Zeng, Qing; Wang, Yi-Nan; Xiong, Feng

2017-08-01

To investigate penis development in children and adolescents aged 0-16 years, and to plot the percentile curve for penis development in different age groups. A total of 3 024 normal male neonates, children, and adolescents aged 0-16 years in Chongqing, China were selected by simple random sampling and stratified cluster sampling. The length and diameter of the penis were measured for all subjects. A descriptive statistical analysis was used to investigate the data characteristics of the penis, and the GAMLSS fitting model was used to plot the percentile curves of P 3 , P 10 , P 25 , P 50 , P 75 , P 90 , and P97 and obtain percentile reference values. The length and diameter of the penis grew rapidly before the age of 1 year, grew relatively slowly from 1 to 11 years old, and entered a rapid growth period from 11 years old. The length of the penis was positively correlated with its diameter (r=0.961, P<0.01). The percentile reference values of penis length and diameter were obtained and the percentile curve was plotted. The growth and development of penis length is consistent with that of penis diameter in male children and adolescents in Chongqing, and 0-1 year and 11-16 years are rapid growth periods of penis length and diameter. The percentile curve of penis length and diameter in children and adolescents aged 0-16 years in Chongqing which has been established will provide a reference for further studies on sexual development in children and adolescents.

Morphological and functional responses of a metal-tolerant sunflower mutant line to a copper-contaminated soil series.

PubMed

Kolbas, Aliaksandr; Kolbas, Natallia; Marchand, Lilian; Herzig, Rolf; Mench, Michel

2018-04-02

The potential use of a metal-tolerant sunflower mutant line for biomonitoring Cu phytoavailability, Cu-induced soil phytotoxicity, and Cu phytoextraction was assessed on a Cu-contaminated soil series (13-1020 mg Cu kg -1 ) obtained by fading a sandy topsoil from a wood preservation site with a similar uncontaminated soil. Morphological and functional plant responses as well as shoot, leaf, and root ionomes were measured after a 1-month pot experiment. Hypocotyl length, shoot and root dry weight (DW) yields, and leaf area gradually decreased as soil Cu exposure rose. Their dose-response curves (DRC) plotted against indicators of Cu exposure were generally well fitted by sigmoidal curves. The half-maximal effective concentration (EC 50 ) of morphological parameters ranged between 203 and 333 mg Cu kg -1 soil, corresponding to 290-430 μg Cu L -1 in the soil pore water, and 20 ± 5 mg Cu kg -1 DW in the shoots. The EC 10 for shoot Cu concentration (13-15 mg Cu kg -1 DW) coincided to 166 mg Cu kg -1 soil. Total chlorophyll content and total antioxidant capacity (TAC) were early biomarkers (EC 10 : 23 and 51 mg Cu kg -1 soil). Their DRC displayed a biphasic response. Photosynthetic pigment contents, e.g., carotenoids, correlated with TAC. Ionome was changed in Cu-stressed roots, shoots, and leaves. Shoot Cu removal peaked roughly at 280 μg Cu L -1 in the soil pore water.

Regenerating time series from ordinal networks.

PubMed

McCullough, Michael; Sakellariou, Konstantinos; Stemler, Thomas; Small, Michael

2017-03-01

Recently proposed ordinal networks not only afford novel methods of nonlinear time series analysis but also constitute stochastic approximations of the deterministic flow time series from which the network models are constructed. In this paper, we construct ordinal networks from discrete sampled continuous chaotic time series and then regenerate new time series by taking random walks on the ordinal network. We then investigate the extent to which the dynamics of the original time series are encoded in the ordinal networks and retained through the process of regenerating new time series by using several distinct quantitative approaches. First, we use recurrence quantification analysis on traditional recurrence plots and order recurrence plots to compare the temporal structure of the original time series with random walk surrogate time series. Second, we estimate the largest Lyapunov exponent from the original time series and investigate the extent to which this invariant measure can be estimated from the surrogate time series. Finally, estimates of correlation dimension are computed to compare the topological properties of the original and surrogate time series dynamics. Our findings show that ordinal networks constructed from univariate time series data constitute stochastic models which approximate important dynamical properties of the original systems.

Regenerating time series from ordinal networks

NASA Astrophysics Data System (ADS)

McCullough, Michael; Sakellariou, Konstantinos; Stemler, Thomas; Small, Michael

2017-03-01

Recently proposed ordinal networks not only afford novel methods of nonlinear time series analysis but also constitute stochastic approximations of the deterministic flow time series from which the network models are constructed. In this paper, we construct ordinal networks from discrete sampled continuous chaotic time series and then regenerate new time series by taking random walks on the ordinal network. We then investigate the extent to which the dynamics of the original time series are encoded in the ordinal networks and retained through the process of regenerating new time series by using several distinct quantitative approaches. First, we use recurrence quantification analysis on traditional recurrence plots and order recurrence plots to compare the temporal structure of the original time series with random walk surrogate time series. Second, we estimate the largest Lyapunov exponent from the original time series and investigate the extent to which this invariant measure can be estimated from the surrogate time series. Finally, estimates of correlation dimension are computed to compare the topological properties of the original and surrogate time series dynamics. Our findings show that ordinal networks constructed from univariate time series data constitute stochastic models which approximate important dynamical properties of the original systems.

Chem Ed Compacts

ERIC Educational Resources Information Center

Wolf, Walter A., Ed.

1978-01-01

Presents four simple laboratory procedures for: preparation of organometallic compounds, a realistic qualitative organic analysis project, a computer program to plot potentiometric titration curves, and preparation of stereoscopic transparencies. (SL)

Phase space trajectories and Lyapunov exponents in the dynamics of an alpha-helical protein lattice with intra- and inter-spine interactions

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

Angelin Jeba, K.; Latha, M. M., E-mail: lathaisaac@yahoo.com; Jain, Sudhir R.

2015-11-15

The nonlinear dynamics of intra- and inter-spine interaction models of alpha-helical proteins is investigated by proposing a Hamiltonian using the first quantized operators. Hamilton's equations of motion are derived, and the dynamics is studied by constructing the trajectories and phase space plots in both cases. The phase space plots display a chaotic behaviour in the dynamics, which opens questions about the relationship between the chaos and exciton-exciton and exciton-phonon interactions. This is verified by plotting the Lyapunov characteristic exponent curves.

Hot Tearing in Aluminium — Copper Alloys

NASA Astrophysics Data System (ADS)

Viano, David; StJohn, David; Grandfield, John; Cáceres, Carlos

For many aluminium alloys, hot tearing susceptibility follows a lambda curve relationship when hot tearing severity is plotted as a function of solute content. In the past, there has been some difficulty quantifying hot tearing. Traditional methods rely upon measuring electrical resistivity or the number and/or length of cracks in tests such as the ring test. In this experimental program, a hot tear test rig was used to investigate a series of binary Al-Cu alloys. This device measures the load imposed on the mushy zone during solidification. Hot tearing susceptibility was quantified in two ways. The first method involved measuring the load at the solidus temperature (548°C). The second method was to radiograph the hot spot and measure the image density of the cracks. Both methods had advantages and disadvantages. It was found that the results from the hot tear rig correlates with other published data using different experimental methods.

Women in Flight Research at NASA Dryden Flight Research Center from 1946 to 1995. Number 6; Monographs in Aerospace History

NASA Technical Reports Server (NTRS)

Powers, Sheryll Goecke

1997-01-01

This monograph discusses the working and living environment of women involved with flight research at NASA Dryden Flight Research Center during the late 1940s and early 1950s. The women engineers, their work and the airplanes they worked on from 1960 to December 1995 are highlighted. The labor intensive data gathering and analysis procedures and instrumentation used before the age of digital computers are explained by showing and describing typical instrumentation found on the X-series aircraft from the X-1 through the X-15. The data reduction technique used to obtain the Mach number position error curve for the X-1 aircraft and which documents the historic first flight to exceed the speed of sound is described and a Mach number and altitude plot from an X-15 flight is shown.

Studies on complex π-π and T-stacking features of imidazole and phenyl/p-halophenyl units in series of 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides and their carbonitrile derivatives: Role of halogens in tuning of conformation

NASA Astrophysics Data System (ADS)

Das, Aniruddha

2017-11-01

5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides (N-phenyl AICA) (2a-e) and 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carbonitriles (N-phenyl AICN) (3a-e) had been synthesized. X-ray crystallographic studies of 2a-e and 3a-e had been performed to identify any distinct change in stacking patterns in their crystal lattice. Single crystal X-ray diffraction studies of 2a-e revealed π-π stack formations with both imidazole and phenyl/p-halophenyl units in anti and syn parallel-displaced (PD)-type dispositions. No π-π stacking of imidazole occurred when the halogen substituent is bromo or iodo; π-π stacking in these cases occurred involving phenyl rings only. The presence of an additional T-stacking had been observed in crystal lattices of 3a-e. Vertical π-π stacking distances in anti-parallel PD-type arrangements as well as T-stacking distances had shown stacking distances short enough to impart stabilization whereas syn-parallel stacking arrangements had got much larger π-π stacking distances to belie any syn-parallel stacking stabilization. DFT studies had been pursued for quantifying the π-π stacking and T-stacking stabilization. The plotted curves for anti-parallel and T-stacked moieties had similarities to the 'Morse potential energy curve for diatomic molecule'. The minima of the curves corresponded to the most stable stacking distances and related energy values indicated stacking stabilization. Similar DFT studies on syn-parallel systems of 2b corresponded to no π-π stacking stabilization at all. Halogen-halogen interactions had also been observed to stabilize the compounds 2d, 2e and 3d. Nano-structural behaviour of the series of compounds 2a-e and 3a-e were thoroughly investigated.

Geologic map of the Cucamonga Peak 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Morton, D.M.; Matti, J.C.; Digital preparation by Koukladas, Catherine; Cossette, P.M.

2001-01-01

a. This Readme; includes in Appendix I, data contained in fif_met.txt b. The same graphic as plotted in 2 above. (Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat pagesize setting influences map scale.) The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Miscellaneous Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U. S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). If roads in some areas, especially forest roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS Cucamonga Peak 7.5’ topographic quadrangle in conjunction with the geologic map.

Geologic map of the Telegraph Peak 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Morton, D.M.; Woodburne, M.O.; Foster, J.H.; Morton, Gregory; Cossette, P.M.

2001-01-01

a. This Readme; includes in Appendix I, data contained in fif_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat pagesize setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Miscellaneous Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U. S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). If roads in some areas, especially forest roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS Telegraph Peak 7.5’ topographic quadrangle in conjunction with the geologic map.

Data Quality Monitoring and Noise Analysis at the EUREF Permanent Network

NASA Astrophysics Data System (ADS)

Kenyeres, A.; Bruyninx, C.

2004-12-01

The EUREF Permanent Network (EPN) includes now more then 150 GNSS stations of different quality and different observation history. The greatest portion of the sites is settled on the tectonically stable parts of Eurasia, where only mm-level yearly displacements are expected. In order to extract the relevant geophysical information, sophisticated analysis tools and stable, long term observations are necessary. As the EPN is operational since 1996, it offers the potential to estimate high quality velocities associated with reliable uncertainties. In order to support this work, a set of efficient and demonstrative tools have been developed to monitor the data and station quality. The periodically upgraded results are displayed on the website of the EPN Central Bureau (CB) (www.epncb.oma.be) in terms of sky plots, graphs of observation percentage, cycle slips and multipath. The different quality plots are indirectly used for the interpretation of the time series. Sudden changes or unusual variation in the time series (beyond the obvious equipment change) often correlates with changes in the environment mirrored by the quality plots. These graphs are vital for the proper interpretation and the understanding of the real processes. Knowing the nuisance factors, we can generate cleaner time series. We are presenting relevant examples of this work. Two kinds of time series plots are displayed at the EPN CB website: raw and improved time series. They are cumulative solutions of the weekly EPN SINEX files using the minimum constraint approach. Within the improved time series the outliers and offsets are already taken into account. We will also present preliminary results of a detailed noise analysis of the EPN time series. The target of this work is twofold: on one side we aim at computing more realistic velocity estimates of the EPN stations and on the other side the information about the station noise characteristics will support the removal and proper interpretation of site-specific phenomena .

Microbial Fuel Cells for Powering Navy Devices

DTIC Science & Technology

2014-01-20

specific MFC being analyzed. Figure 3 depicts simulated voltage vs. current plots (black curves) and corresponding power vs. current...Powering Navy Devices 7     Fig. 3 – Simulated voltage vs current and power vs current polarization plots for a two- chamber MFC in which membrane...the anode is generated by fermentation of glucose by other microorganisms in the sediment represented by clostridium in Fig. 4. The products of the

Universal properties of galactic rotation curves and a first principles derivation of the Tully-Fisher relation

NASA Astrophysics Data System (ADS)

O'Brien, James G.; Chiarelli, Thomas L.; Mannheim, Philip D.

2018-07-01

In a recent paper McGaugh, Lelli, and Schombert showed that in an empirical plot of the observed centripetal accelerations in spiral galaxies against those predicted by the Newtonian gravity of the luminous matter in those galaxies the data points occupied a remarkably narrow band. While one could summarize the mean properties of the band by drawing a single mean curve through it, by fitting the band with the illustrative conformal gravity theory with fits that fill out the width of the band we show here that the width of the band is just as physically significant. We show that at very low luminous Newtonian accelerations the plot can become independent of the luminous Newtonian contribution altogether, but still be non-trivial due to the contribution of matter outside of the galaxies (viz. the rest of the visible universe). We present a new empirical plot of the difference between the observed centripetal accelerations and the luminous Newtonian expectations as a function of distance from the centers of galaxies, and show that at distances greater than 10 kpc the plot also occupies a remarkably narrow band, one even close to constant. Using the conformal gravity theory we provide a first principles derivation of the empirical Tully-Fisher relation.

The structure, function and value of urban forests in California communities

Treesearch

E. Gregory McPherson; Qingfu Xiao; Natalie S. van Doorn; John de Goede; Jacquelyn Bjorkman; Allan Hollander; Ryan M. Boynton; James F. Quinn; James H. Thorne

2017-01-01

This study used tree data from field plots in urban areas to describe forest structure in urban areas throughout California. The plot data were used with numerical models to calculate several ecosystem services produced by trees. A series of transfer functions were calculated to scale-up results from the plots to the landscape using urban tree canopy (UTC) mapped at 1-...

Characterizing time series via complexity-entropy curves

NASA Astrophysics Data System (ADS)

Ribeiro, Haroldo V.; Jauregui, Max; Zunino, Luciano; Lenzi, Ervin K.

2017-06-01

The search for patterns in time series is a very common task when dealing with complex systems. This is usually accomplished by employing a complexity measure such as entropies and fractal dimensions. However, such measures usually only capture a single aspect of the system dynamics. Here, we propose a family of complexity measures for time series based on a generalization of the complexity-entropy causality plane. By replacing the Shannon entropy by a monoparametric entropy (Tsallis q entropy) and after considering the proper generalization of the statistical complexity (q complexity), we build up a parametric curve (the q -complexity-entropy curve) that is used for characterizing and classifying time series. Based on simple exact results and numerical simulations of stochastic processes, we show that these curves can distinguish among different long-range, short-range, and oscillating correlated behaviors. Also, we verify that simulated chaotic and stochastic time series can be distinguished based on whether these curves are open or closed. We further test this technique in experimental scenarios related to chaotic laser intensity, stock price, sunspot, and geomagnetic dynamics, confirming its usefulness. Finally, we prove that these curves enhance the automatic classification of time series with long-range correlations and interbeat intervals of healthy subjects and patients with heart disease.

Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code. Volume 1; Analysis and Results

NASA Technical Reports Server (NTRS)

Meyer, Harold D.

1999-01-01

This report provides a study of rotor and stator scattering using the SOURCE3D Rotor Wake/Stator Interaction Code. SOURCE3D is a quasi-three-dimensional computer program that uses three-dimensional acoustics and two-dimensional cascade load response theory to calculate rotor and stator modal reflection and transmission (scattering) coefficients. SOURCE3D is at the core of the TFaNS (Theoretical Fan Noise Design/Prediction System), developed for NASA, which provides complete fully coupled (inlet, rotor, stator, exit) noise solutions for turbofan engines. The reason for studying scattering is that we must first understand the behavior of the individual scattering coefficients provided by SOURCE3D, before eventually understanding the more complicated predictions from TFaNS. To study scattering, we have derived a large number of scattering curves for vane and blade rows. The curves are plots of output wave power divided by input wave power (in dB units) versus vane/blade ratio. Some of these plots are shown in this report. All of the plots are provided in a separate volume. To assist in understanding the plots, formulas have been derived for special vane/blade ratios for which wavefronts are either parallel or normal to rotor or stator chords. From the plots, we have found that, for the most part, there was strong transmission and weak reflection over most of the vane/blade ratio range for the stator. For the rotor, there was little transmission loss.

Experimental defaunation of terrestrial mammalian herbivores alters tropical rainforest understorey diversity

PubMed Central

Camargo-Sanabria, Angela A.; Mendoza, Eduardo; Guevara, Roger; Martínez-Ramos, Miguel; Dirzo, Rodolfo

2015-01-01

It has been suggested that tropical defaunation may unleash community-wide cascading effects, leading to reductions in plant diversity. However, experimental evidence establishing cause–effect relationships thereof is poor. Through a 5 year exclosure experiment, we tested the hypothesis that mammalian defaunation affects tree seedling/sapling community dynamics leading to reductions in understorey plant diversity. We established plot triplets (n = 25) representing three defaunation contexts: terrestrial-mammal exclosure (TE), medium/large mammal exclosure (PE) and open access controls (C). Seedlings/saplings 30–100 cm tall were marked and identified within each of these plots and re-censused three times to record survival and recruitment. In the periods 2010–2011 and 2011–2013, survival was greater in PE than in C plots and recruitment was higher in TE plots than in C plots. Overall, seedling density increased by 61% in TE plots and 23% in PE plots, whereas it decreased by 5% in C plots. Common species highly consumed by mammals (e.g. Brosimum alicastrum and Ampelocera hottlei) increased in their abundance in TE plots. Rarefaction curves showed that species diversity decreased in TE plots from 2008 to 2013, whereas it remained similar for C plots. Given the prevalence of tropical defaunation, we posit this is an anthropogenic effect threatening the maintenance of tropical forest diversity. PMID:25540281

ELECTRONIC ANALOG COMPUTER FOR DETERMINING RADIOACTIVE DISINTEGRATION

DOEpatents

Robinson, H.P.

1959-07-14

A computer is presented for determining growth and decay curves for elements in a radioactive disintegration series wherein one unstable element decays to form a second unstable element or isotope, which in turn forms a third element, etc. The growth and decay curves of radioactive elements are simulated by the charge and discharge curves of a resistance-capacitance network. Several such networks having readily adjustable values are connected in series with an amplifier between each successive pair. The time constant of each of the various networks is set proportional to the half-life of a corresponding element in the series represented and the charge and discharge curves of each of the networks simulates the element growth and decay curve.

Streamflow properties from time series of surface velocity and stage

USGS Publications Warehouse

Plant, W.J.; Keller, W.C.; Hayes, K.; Spicer, K.

2005-01-01

Time series of surface velocity and stage have been collected simultaneously. Surface velocity was measured using an array of newly developed continuous-wave microwave sensors. Stage was obtained from the standard U.S. Geological Survey (USGS) measurements. The depth of the river was measured several times during our experiments using sounding weights. The data clearly showed that the point of zero flow was not the bottom at the measurement site, indicating that a downstream control exists. Fathometer measurements confirmed this finding. A model of the surface velocity expected at a site having a downstream control was developed. The model showed that the standard form for the friction velocity does not apply to sites where a downstream control exists. This model fit our measured surface velocity versus stage plots very well with reasonable values of the parameters. Discharges computed using the surface velocities and measured depths matched the USGS rating curve for the site. Values of depth-weighted mean velocities derived from our data did not agree with those expected from Manning's equation due to the downstream control. These results suggest that if real-time surface velocities were available at a gauging station, unstable stream beds could be monitored. Journal of Hydraulic Engineering ?? ASCE.

The Design and Use of Planetary Science Video Games to Teach Content while Enhancing Spatial Reasoning Skills

NASA Astrophysics Data System (ADS)

Ziffer, Julie; Nadirli, Orkhan; Rudnick, Benjamin; Pinkham, Sunny; Montgomery, Benjamin

2016-10-01

Traditional teaching of Planetary Science requires students to possess well developed spatial reasoning skills (SRS). Recent research has demonstrated that SRS, long known to be crucial to math and science success, can be improved among students who lack these skills (Sorby et al., 2009). Teaching spatial reasoning is particularly valuable to women and minorities who, through societal pressure, often doubt their abilities (Hill et al., 2010). To address SRS deficiencies, our team is developing video games that embed SRS training into Planetary Science content. Our first game, on Moon Phases, addresses the two primary challenges faced by students trying to understand the Sun-Earth-Moon system: 1) visualizing the system (specifically the difference between the Sun-Earth orbital plane and the Earth-Moon orbital plane) and 2) comprehending the relationship between time and the position-phase of the Moon. In our second video game, the student varies an asteroid's rotational speed, shape, and orientation to the light source while observing how these changes effect the resulting light curve. To correctly pair objects to their light curves, students use spatial reasoning skills to imagine how light scattering off a three dimensional rotating object is imaged on a sensor plane and is then reduced to a series of points on a light curve plot. These two games represent the first of our developing suite of high-interest video games designed to teach content while increasing the student's competence in spatial reasoning.

Malathion-induced inhibition of human plasma cholinesterase studied by the fluorescence spectroscopy method

NASA Astrophysics Data System (ADS)

Pavelkić, V. M.; Krinulović, K. S.; Savić, J. Z.; Ilić, M. A.

2008-05-01

The in vitro effect of technical grade malathion was assessed via the kinetic parameters of human plasma butyrylcholinesterase (BChE) using N-methylindoxyl acetate as a substrate for BChE. An inhibitor kinetics study demonstrated the existence of a biphasic inhibition curve, indicating high-and low-affinity binding sites of malathion. The IC 50 values as calculated from the experimental inhibition curves were 1.33 × 10-9 and 1.48 × 10-5 M for the high-and low-affinity binding sites, respectively; Hill’s analysis gave 1.29 × 10-9 and 1.38 × 10-6 M. The Cornish-Bowden plots and their secondary plots indicated that the nature of inhibition was of mixed type with the predominant competitive character of both affinity binding sites.

Comparison of the efficacy of steam sterilization indicators.

PubMed Central

Lee, C H; Montville, T J; Sinskey, A J

1979-01-01

Twenty-one commercially available chemical steam sterilization indicators were processed in an empty autoclave for various times at temperatures between 240 and 270 degrees F (ca. 116 and 132 degrees C). The time required to reach a sterilized reading at each temperature was plotted on a semilogarithmic time-temperature plot and compared with the time-temperature sterilization curve for Bacillus stearothermophilus. Five of the indicators had time-temperature kinetics similar to those of B. stearothermophilus, but three of these overestimated the effect of processing. Two of the indicators overestimated the effect of processing and were less sensitive to temperature changes when was B. stearothermophilus. Thirteen of the indicators had time-temperature curves that crossed the B. stearothermophilus plot. One indicator produced such ambiguous results that no determinations could be made with it. Out of 21 indicators tested, only 2 appear to be capable of accurately integrating the time-temperature effect at temperatures between 240 and 270 degrees F. The other indicators should be used only after careful analysis of their suitability for use at a given temperature. PMID:485144

Flood-frequency analyses, Manual of Hydrology: Part 3

USGS Publications Warehouse

Dalrymple, Tate

1960-01-01

This report describes the method used by the U.S. Geological Survey to determine the magnitude and frequency of momentary peak discharges at any place on a stream, whether a gaging-station record is available or not. The method is applicable to a region of any size, as a river basin or a State, so long as the region is hydrologically homogeneous. The analysis provides two curves. The first expresses the flood discharge-time relation, showing variation of peak discharge, expressed as a ratio to the mean annual flood, with recurrence interval. The second relates the mean annual flood to the size of drainage area alone, or to the size area and other significant basin characteristics. A frequency curve may be defined for any place in the region by use of these two curves. The procedure is: (a) measure the drainage area and other appropriate basin characteristics from maps; (b) from the second curve, select the mean annual flood corresponding to the proper drainage area factors; (c) from the first curve, select ratios of peak discharge to mean annual flood for selected recurrence intervals, as 2, 10, 25, and 50 years; and (d) multiply these ratios by the mean annual flood and plot the resulting discharges of known frequency to define the frequency curve. Two reports not previously given general circulation are included as sections of this report. These are 'Plotting Positions in Frequency Analysis' by W. B. Langbein, and 'Characteristics of Frequency Curves Based on a Theoretical 1,000-Year Record' by M. A. Benson.

Hybrid poplar grows poorly on acid spoil banks at high elevations in West Virginia

Treesearch

George R., Jr. Trimble

1963-01-01

In the early 1950s, a region-wide series of hybrid poplar clonal tests was begun in the Northeast to evaluate the performance of 50 selected clones under a variety of site and climatic conditions. The basic test unit was a block of 50 randomized plots-1 plot for each of the 50 clones. In each plot, 16 cuttings were planted at 4-foot spacing.

Geologic map of the San Bernardino North 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Miller, F.K.; Matti, J.C.

2001-01-01

3. Portable Document Format (.pdf) files of: a. This Readme; includes an Appendix, containing data found in sbnorth_met.txt . b. The Description of Map Units identical to that found on the plot of the PostScript file. c. The same graphic as plotted in 2 above. (Test plots from this .pdf do not produce 1:24,000-scale maps. Use Adobe Acrobat pagesize setting to control map scale.) The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Miscellaneous Investigations Series (I-series) maps. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U. S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). If roads in some areas, especially forest roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS San Bernardino North 7.5’ topographic quadrangle in conjunction with the geologic map.

SpectraPLOT, Visualization Package with a User-Friendly Graphical Interface

NASA Astrophysics Data System (ADS)

Sebald, James; Macfarlane, Joseph; Golovkin, Igor

2017-10-01

SPECT3D is a collisional-radiative spectral analysis package designed to compute detailed emission, absorption, or x-ray scattering spectra, filtered images, XRD signals, and other synthetic diagnostics. The spectra and images are computed for virtual detectors by post-processing the results of hydrodynamics simulations in 1D, 2D, and 3D geometries. SPECT3D can account for a variety of instrumental response effects so that direct comparisons between simulations and experimental measurements can be made. SpectraPLOT is a user-friendly graphical interface for viewing a wide variety of results from SPECT3D simulations, and applying various instrumental effects to the simulated images and spectra. We will present SpectraPLOT's ability to display a variety of data, including spectra, images, light curves, streaked spectra, space-resolved spectra, and drilldown plasma property plots, for an argon-doped capsule implosion experiment example. Future SpectraPLOT features and enhancements will also be discussed.

Recurrence quantification analysis of electrically evoked surface EMG signal.

PubMed

Liu, Chunling; Wang, Xu

2005-01-01

Recurrence Plot is a quite useful tool used in time-series analysis, in particular for measuring unstable periodic orbits embedded in a chaotic dynamical system. This paper introduced the structures of the Recurrence Plot and the ways of the plot coming into being. Then the way of the quantification of the Recurrence Plot is defined. In this paper, one of the possible applications of Recurrence Quantification Analysis (RQA) strategy to the analysis of electrical stimulation evoked surface EMG. The result shows the percent determination is increased along with stimulation intensity.

[Kaup index in 16 887 singleton neonates with a gestational age of 27-42 weeks in Shenzhen, China].

PubMed

Huang, Xiao-Yun; Liu, Hui-Long; Lei, Min; Lian, Zhao-Hui; Mai, Hui-Fen

2018-05-01

To study the Kaup index (KI), an index used to evaluate body burliness and nutritional status, of neonates with a gestational age (GA) of 27-42 weeks at birth, and to establish the percentile curves of KI. Cross-sectional cluster sampling was performed from April 2013 to September 2015 to select 16 887 singleton neonates with a GA of 27-42 weeks in two hospitals in Shenzhen, China. Body weight and body length were measured to calculate KI. The percentile curves of KI were plotted in these neonates. Mean KIs and corresponding standard deviations were obtained for singleton neonates with a gestational age of 27-42 weeks (in male, female, and mixed groups), and the 3rd-97th percentile curves of KI were plotted. The singleton neonates with a GA of 27 weeks had the lowest 50th percentile value of KI, and KI gradually increased with GA. Boys had a higher 50th percentile value of KI than girls in each GA group. In all groups except the 33-week GA group, boys had a higher mean KI than girls, and there was a significant difference in the mean KI between boys and girls in the GA groups of 34 and 36-40 weeks (P<0.05). KI of neonates at birth increases with GA, suggesting that body density and body burliness increase with GA. Boys have better body burliness than girls at birth. The percentile curves of KI plotted for singleton neonates with a GA of 27-42 weeks (in male, female, and mixed groups) can provide a reference for evaluating the body burliness and nutritional status of neonates at birth in Shenzhen.

New assay of protective activity of Rocky Mountain spotted fever vaccines.

PubMed Central

Anacker, R L; Smith, R F; Mann, R E; Hamilton, M A

1976-01-01

Areas under the fever curves of guinea pigs inoculated with Rocky Mountain spotted fever vaccine over a restricted dose range and infected with a standardized dose of Rickettsia rickettsii varied linearly with log10 dose of vaccine. A calculator was programmed to plot fever curves and calculate the vaccine dose that reduced the fever of infected animals by 50%. PMID:823177

Monitoring baseline suspended sediment in forested basins: the effects of sampling on suspended sediment rating curves

Treesearch

Robert B. Thomas

1988-01-01

Abstract - Rating curves are widely used for directly assessing changes in the suspended sediment delivery process and indirectly for estimating total yields. Four sampling methods were simulated-over a 31-day record of suspended sediment from the North Fork of the Mad River near Korbel, California. The position and size of the four groups of plotted slope/intercept...

The ROC Curves of Fused Independent Classification Systems

DTIC Science & Technology

2008-09-01

spectral settings arises in many fields of study; in medicine, the detection of a cancer; in marketing , the detection of the best customer base; in the...p ≤ 0.4 p/3 + 2/3, 0.4 ≤ p ≤ 1.0 fB(p) = tanh( 4p ) fC(p) = p1/3 The following plots will show how these ROC curves combine, and how the optimal

Computer user's manual for a generalized curve fit and plotting program

NASA Technical Reports Server (NTRS)

Schlagheck, R. A.; Beadle, B. D., II; Dolerhie, B. D., Jr.; Owen, J. W.

1973-01-01

A FORTRAN coded program has been developed for generating plotted output graphs on 8-1/2 by 11-inch paper. The program is designed to be used by engineers, scientists, and non-programming personnel on any IBM 1130 system that includes a 1627 plotter. The program has been written to provide a fast and efficient method of displaying plotted data without having to generate any additions. Various output options are available to the program user for displaying data in four different types of formatted plots. These options include discrete linear, continuous, and histogram graphical outputs. The manual contains information about the use and operation of this program. A mathematical description of the least squares goodness of fit test is presented. A program listing is also included.

Experimental defaunation of terrestrial mammalian herbivores alters tropical rainforest understorey diversity.

PubMed

Camargo-Sanabria, Angela A; Mendoza, Eduardo; Guevara, Roger; Martínez-Ramos, Miguel; Dirzo, Rodolfo

2015-02-07

It has been suggested that tropical defaunation may unleash community-wide cascading effects, leading to reductions in plant diversity. However, experimental evidence establishing cause-effect relationships thereof is poor. Through a 5 year exclosure experiment, we tested the hypothesis that mammalian defaunation affects tree seedling/sapling community dynamics leading to reductions in understorey plant diversity. We established plot triplets (n = 25) representing three defaunation contexts: terrestrial-mammal exclosure (TE), medium/large mammal exclosure (PE) and open access controls (C). Seedlings/saplings 30-100 cm tall were marked and identified within each of these plots and re-censused three times to record survival and recruitment. In the periods 2010-2011 and 2011-2013, survival was greater in PE than in C plots and recruitment was higher in TE plots than in C plots. Overall, seedling density increased by 61% in TE plots and 23% in PE plots, whereas it decreased by 5% in C plots. Common species highly consumed by mammals (e.g. Brosimum alicastrum and Ampelocera hottlei) increased in their abundance in TE plots. Rarefaction curves showed that species diversity decreased in TE plots from 2008 to 2013, whereas it remained similar for C plots. Given the prevalence of tropical defaunation, we posit this is an anthropogenic effect threatening the maintenance of tropical forest diversity. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

New well testing applications of the pressure derivative

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

Onur, M.

1989-01-01

This work presents new derivative type curves based on a new derivative group which is equal to the dimensionless pressure group divided by its logarithmic derivative with respect to dimensionless time group. One major advantage of these type curves is that the type-curve match of field pressure/pressure-derivative data with the new derivative type curves is accomplished by moving the field data plot in only the horizontal direction. This type-curve match fixes time match-point values. The pressure change versus time data is then matched with the dimensionless pressure solution to determine match-point values. Well/reservoir parameters can then be estimated in themore » standard way. This two step type-curve matching procedure increases the likelihood of obtaining a unique match. Moreover, the unique correspondence between the ordinate of the field data plot and the new derivative type curves should prove useful in determining whether given field data actually represents the well/reservoir model assumed by a selected type curve solution. It is also shown that the basic idea used in construction the type curves can be used to ensure that proper semilog straight lines are chosen when analyzing pressure data by semilog methods. Analysis of both drawdown and buildup data is considered and actual field cases are analyzed using the new derivative type curves and the semilog identification method. This work also presents new methods based on the pressure derivative to analyze buildup data obtained at a well (fracture or unfractured) produced to pseudosteady-state prior to shut-in. By using a method of analysis based on the pressure derivative, it is shown that a well's drainage area at the instant of shut-in and the flow capacity can be computed directly from buildup data even in cases where conventional semilog straight lines are not well-defined.« less

Peristaltic flow of Powell-Eyring fluid in curved channel with heat transfer: A useful application in biomedicine.

PubMed

Hina, S; Mustafa, M; Hayat, T; Alsaedi, A

2016-10-01

In this work, we explore the heat transfer characteristics in the peristaltic transport of Powell-Eyring fluid inside a curved channel with complaint walls. The study has motivation toward the understanding of blood flow in microcirculatory system. Formulation is developed in the existence of velocity slip and temperature jump conditions. Perturbation approach has been utilized to present series expressions of axial velocity and temperature distributions. Streamlines are prepared to analyze the interesting phenomenon of trapping. Moreover, the plots of heat transfer coefficient for a broad range of embedded parameters are presented and discussed. The results indicate that slip effects substantially influence the velocity and temperature distributions. Axial flow accelerates when slip parameter is incremented. Temperature rises and wall heat flux grows when viscous dissipation effect is strengthened. In contrast to the planar channels, here velocity and temperature functions do not exhibit symmetry with respect to the central line. In addition, bolus size and its shape are different in upper and lower portions of the channel. Heat transfer coefficient enlarges when the curvature effects are reduced. The behaviors of wall tension and wall mass parameters on the profiles are qualitatively similar. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The determination of substrate conditions from the orientations of solitary rugose corals

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

Bolton, J.C.; Driese, S.G.

1990-10-01

The substrate conditions of mudstone strata formed in ancient epicontinental settings may be determined from taphonomic assemblages of solitary rugose corals. Equal-area plots on the orientations of preserved corals can be used to infer whether subsequent hydrodynamic conditions affected any post-mortem reworking of the corals. Mechanically stable positions for curved corals can be determined. Curved corals preserved in mechanically stable positions are interpreted to have been deposited on firm or hard substrates. Curved corals preserved in mechanically unstable positions were probably embedded in soft or soupy substrates.

Non-equilibrium effects in nanoparticulate assemblies, bond-disordered ferromagnets, and collections of two-level subsystems

NASA Astrophysics Data System (ADS)

Viddal, Candice April Harder

The central concern of this thesis is the study of non-equilibrium behaviour in magnetic materials and its interpretation within the framework of a theoretical model based on the Preisach hypothesis, which decomposes all magnetic materials into a collection of bistable units. More specifically, we have performed comprehensive experimental characterizations of a variety of magnetic materials, including a naturally occurring mineral of nanodimensional titanomagnetite particles embedded in volcanic glass, a compressed powder of nanodimensional magnetite particles immobilized in an organic binder, a thin film of nanodimensional Fe particles embedded in alumina, and a series of sintered, bond-disordered CaxSr1-xRuO3 ferromagnets. We have measured (a) the initial magnetizing curve, the magnetizing remanence, the descending branch of the major hysteresis loop and the demagnetizing remanence as a function of applied field over a broad range of temperatures, (b) the field cooled moment, the zero field cooled moment, the thermoremanent moment and the isothermal remanent moment as a function of temperature in a broad range of applied fields, and (c) viscosity isotherms in a series of negative holding fields following recoil from positive saturation as a function of time over a wide range of temperatures. The measurements were compared with numerical simulations based on a Preisach model ensemble of thermally activated two-level subsystems, characterized individually by a double well free energy profile in a two-dimensional configuration space, an elementary moment reversal, a dissipation field and a bias field, and characterized collectively by a distribution of these characteristic fields. Our efforts were concentrated on two principal spheres of investigation. (1) By performing detailed numerical simulations of the relaxation response of model Preisach collections of two-level subsystems under the same field and temperature protocols used to probe experimentally the relaxation dynamics of spin glasses, we have been able to show that aging, memory and rejuvenation effects are not unique to collectively ordered materials with spin glass correlations, but rather are an ubiquitous feature of materials with a broad distribution of energy barriers where relaxation proceeds as a superposition of independent overbarrier activation events, each with its own characteristic relaxation time constant. (2) The second line of inquiry pertains to probing the two principal mechanisms, thermal fluctuations and barrier growth, which are jointly responsible for shaping the measured temperature dependence of the magnetic properties of all magnetic materials which exhibit a history dependent response to an external field excitation. We have proposed a general strategy for isolating and quantifying these two mechanisms which is based on the analysis of viscosity isotherms and, in particular, on a plot of T ln(tr/tau0) versus Ha, where t r is the time at which a viscosity isotherm measured in a field H a at temperature T reverses sign. When the magnetic response is dominated by thermal activation events, this plot will yield a universal curve from which it is possible to extract the mean elementary moment reversal and to reconstruct the distribution of metastable state excitation energies. When barrier growth dominates, the plot fractures into a family of isothermal curves from which it is, in principle, possible to reconstruct the evolution of the free energy landscape with temperature and to observe the collapse of the barriers as the material is warmed through the critical ordering temperature. The strategy is applied to the analysis of all four materials listed above.

Perceptibility curve test for digital radiographs before and after correction for attenuation and correction for attenuation and visual response.

PubMed

Li, G; Welander, U; Yoshiura, K; Shi, X-Q; McDavid, W D

2003-11-01

Two digital image processing methods, correction for X-ray attenuation and correction for attenuation and visual response, have been developed. The aim of the present study was to compare digital radiographs before and after correction for attenuation and correction for attenuation and visual response by means of a perceptibility curve test. Radiographs were exposed of an aluminium test object containing holes ranging from 0.03 mm to 0.30 mm with increments of 0.03 mm. Fourteen radiographs were exposed with the Dixi system (Planmeca Oy, Helsinki, Finland) and twelve radiographs were exposed with the F1 iOX system (Fimet Oy, Monninkylä, Finland) from low to high exposures covering the full exposure ranges of the systems. Radiographs obtained from the Dixi and F1 iOX systems were 12 bit and 8 bit images, respectively. Original radiographs were then processed for correction for attenuation and correction for attenuation and visual response. Thus, two series of radiographs were created. Ten viewers evaluated all the radiographs in the same random order under the same viewing conditions. The object detail having the lowest perceptible contrast was recorded for each observer. Perceptibility curves were plotted according to the mean of observer data. The perceptibility curves for processed radiographs obtained with the F1 iOX system are higher than those for originals in the exposure range up to the peak, where the curves are basically the same. For radiographs exposed with the Dixi system, perceptibility curves for processed radiographs are higher than those for originals for all exposures. Perceptibility curves show that for 8 bit radiographs obtained from the F1 iOX system, the contrast threshold was increased in processed radiographs up to the peak, while for 12 bit radiographs obtained with the Dixi system, the contrast threshold was increased in processed radiographs for all exposures. When comparisons were made between radiographs corrected for attenuation and corrected for attenuation and visual response, basically no differences were found. Radiographs processed for correction for attenuation and correction for attenuation and visual response may improve perception, especially for 12 bit originals.

QUANTITATIVE STUDIES ON THE TOTAL PLASMIN AND THE TRYPSIN INHIBITOR OF HUMAN BLOOD SERUM

PubMed Central

Todd, Edgar W.

1949-01-01

The total plasmin and the trypsin inhibitor were titrated separately in samples of serum taken at weekly intervals from three different groups of scarlet fever patients: (a) those who did not develop any complications, (b) those who developed purulent complications, and (c) those who developed rheumatic fever. When these determinations were plotted, it was found that the resulting curves showed characteristic patterns for each of the diseases investigated. The uncomplicated cases had plasmin curves which were considerably higher on the charts than the inhibitor curves. The septic cases had plasmin and inhibitor curves which were closer together on the charts. The rheumatic cases had plasmin and inhibitor curves which were close together and which crossed at the time of rheumatic activity so that the inhibitor curve reached a higher level than the plasmin curve. PMID:18110885

Computer acquired performance data from an etched-rhenium, molybdenum planar diode

NASA Technical Reports Server (NTRS)

Manista, E. J.

1972-01-01

Performance data from an etched-rhenium, molybdenum thermionic converter are presented. The planar converter has a guard-ringed collector and a fixed spacing of 0.254 mm (10 mils). The data were acquired by using a computer and are available on microfiche as individual or composite parametric current, voltage curves. The parameters are the temperatures of the emitter T sub E, collector T sub C and cesium reservoir T sub R. The composite plots have constant T sub E, and varying T sub C or T sub R, or both. The envelope and composite plots having constant I sub E are presented. The diode was tested at increments between 1500 and 2000 K for the emitter, 750 and 1100 K for the collector, and 540 and 640 K for the reservoir. In all, 774 individual current, voltage curves were obtained.

Interpretation of diagnostic data: 4. How to do it with a more complex table.

PubMed

1983-10-15

A more complex table is especially useful when a diagnostic test produces a wide range of results and your patient's levels are near one of the extremes. The following guidelines will be useful: Identify the several cut-off points that could be used. Fill in a complex table along the lines of Table I, showing the numbers of patients at each level who have and do not have the target disorder. Generate a simple table for each cut-off point, as in Table II, and determine the sensitivity (TP rate) and specificity (TN rate) at each of them. Select the cut-off point that makes the most sense for your patient's test result and proceed as in parts 2 and 3 of our series. Alternatively, construct an ROC curve by plotting the TP and FP rates that attend each cut-off point. If you keep your tables and ROC curves close at hand, you will gradually accumulate a set of very useful guides. However, if you looked very hard at what was happening, you will probably have noticed that they are not very useful for patients whose test results fall in the middle zones, or for those with just one positive result of two tests; the post-test likelihood of disease in these patients lurches back and forth past 50%, depending on where the cut-off point is. We will show you how to tackle this problem in part 5 of our series. It involves some maths, but you will find that its very powerful clinical application can be achieved with a simple nomogram or with some simple calculations.

VStar: Variable star data visualization and analysis tool

NASA Astrophysics Data System (ADS)

VStar Team

2014-07-01

VStar is a multi-platform, easy-to-use variable star data visualization and analysis tool. Data for a star can be read from the AAVSO (American Association of Variable Star Observers) database or from CSV and TSV files. VStar displays light curves and phase plots, can produce a mean curve, and analyzes time-frequency with Weighted Wavelet Z-Transform. It offers tools for period analysis, filtering, and other functions.

Evaluation of Delamination Onset and Growth Characterization Methods under Mode I Fatigue Loading

NASA Technical Reports Server (NTRS)

Murri, Gretchen B.

2013-01-01

Double-cantilevered beam specimens of IM7/8552 graphite/epoxy from two different manufacturers were tested in static and fatigue to compare the material characterization data and to evaluate a proposed ASTM standard for generating Paris Law equations for delamination growth. Static results were used to generate compliance calibration constants for reducing the fatigue data, and a delamination resistance curve, GIR, for each material. Specimens were tested in fatigue at different initial cyclic GImax levels to determine a delamination onset curve and the delamination growth rate. The delamination onset curve equations were similar for the two sources. Delamination growth rate was calculated by plotting da/dN versus GImax on a log-log scale and fitting a Paris Law. Two different data reduction methods were used to calculate da/dN. To determine the effects of fiber-bridging, growth results were normalized by the delamination resistance curves. Paris Law exponents decreased by 31% to 37% after normalizing the data. Visual data records from the fatigue tests were used to calculate individual compliance constants from the fatigue data. The resulting da/dN versus GImax plots showed improved repeatability for each source, compared to using averaged static data. The Paris Law expressions for the two sources showed the closest agreement using the individually fit compliance data.

The Eclipsing Binary On-Line Atlas (EBOLA)

NASA Astrophysics Data System (ADS)

Bradstreet, D. H.; Steelman, D. P.; Sanders, S. J.; Hargis, J. R.

2004-05-01

In conjunction with the upcoming release of \\it Binary Maker 3.0, an extensive on-line database of eclipsing binaries is being made available. The purposes of the atlas are: \\begin {enumerate} Allow quick and easy access to information on published eclipsing binaries. Amass a consistent database of light and radial velocity curve solutions to aid in solving new systems. Provide invaluable querying capabilities on all of the parameters of the systems so that informative research can be quickly accomplished on a multitude of published results. Aid observers in establishing new observing programs based upon stars needing new light and/or radial velocity curves. Encourage workers to submit their published results so that others may have easy access to their work. Provide a vast but easily accessible storehouse of information on eclipsing binaries to accelerate the process of understanding analysis techniques and current work in the field. \\end {enumerate} The database will eventually consist of all published eclipsing binaries with light curve solutions. The following information and data will be supplied whenever available for each binary: original light curves in all bandpasses, original radial velocity observations, light curve parameters, RA and Dec, V-magnitudes, spectral types, color indices, periods, binary type, 3D representation of the system near quadrature, plots of the original light curves and synthetic models, plots of the radial velocity observations with theoretical models, and \\it Binary Maker 3.0 data files (parameter, light curve, radial velocity). The pertinent references for each star are also given with hyperlinks directly to the papers via the NASA Abstract website for downloading, if available. In addition the Atlas has extensive searching options so that workers can specifically search for binaries with specific characteristics. The website has more than 150 systems already uploaded. The URL for the site is http://ebola.eastern.edu/.

Experimental evidence for negative turgor pressure in small leaf cells of Robinia pseudoacacia L versus large cells of Metasequoia glyptostroboides Hu et W.C. Cheng. 2. Höfler diagrams below the volume of zero turgor and the theoretical implication for pressure-volume curves of living cells.

PubMed

Yang, Dongmei; Li, Junhui; Ding, Yiting; Tyree, Melvin T

2017-03-01

The physiological advantages of negative turgor pressure, P t , in leaf cells are water saving and homeostasis of reactants. This paper advances methods for detecting the occurrence of negative P t in leaves. Biomechanical models of pressure-volume (PV) curves predict that negative P t does not change the linearity of PV curve plots of inverse balance pressure, P B , versus relative water loss, but it does predict changes in either the y-intercept or the x-intercept of the plots depending on where cell collapse occurs in the P B domain because of negative P t . PV curve analysis of Robinia leaves revealed a shift in the x-intercept (x-axis is relative water loss) of PV curves, caused by negative P t of palisade cells. The low x-intercept of the PV curve was explained by the non-collapse of palisade cells in Robinia in the P B domain. Non-collapse means that P t smoothly falls from positive to negative values with decreasing cell volume without a dramatic change in slope. The magnitude of negative turgor in non-collapsing living cells was as low as -1.3 MPa and the relative volume of the non-collapsing cell equaled 58% of the total leaf cell volume. This study adds to the growing evidence for negative P t . © 2016 John Wiley & Sons Ltd.

User Manual for the Data-Series Interface of the Gr Application Software

USGS Publications Warehouse

Donovan, John M.

2009-01-01

This manual describes the data-series interface for the Gr Application software. Basic tasks such as plotting, editing, manipulating, and printing data series are presented. The properties of the various types of data objects and graphical objects used within the application, and the relationships between them also are presented. Descriptions of compatible data-series file formats are provided.

Real-time Series Resistance Monitoring in PV Systems; NREL (National Renewable Energy Laboratory)

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

Deceglie, M. G.; Silverman, T. J.; Marion, B.

We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IVmore » curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Analysis of water retention curve as a potential tool in comparing the effect of different soil management in two olive orchard in southern Spain

NASA Astrophysics Data System (ADS)

Guzmán, G.; Gómez, J. A.; Giráldez, J. V.

2010-05-01

Water soil erosion is one of the major concerns in agricultural areas in Southern Spain, and the use of cover crops has been recommended as an alternative to tillage to prevent, or mitigate, soil erosion. This change of soil management implies a progressive modification of soil chemical, biological and physical properties which to date, have been documented by a limited number of studies. In this communication we describe a methodology based on the modification of the water retention curves of intact cores, present the results obtained in two olive orchards in Southern Spain, and compare them with several chemical and physical properties measured simultaneously in the orchards. The experimental areas were located in Benacazón and Pedrera, Seville province in Southern Spain, and at each location two experimental plots were established. One of the plots was under traditional tillage management and the other under cover crop soil management. The slope at the plots was 12 and 4% respectively. Soil samples were taken at both plots differentiating between the inter tree areas and the under the olive canopy areas, between two different depths: 0-10 cm and 10-20 cm. These resulted in eight different sampling areas (2x2x2). Samples were taken three year after establishing the experiments. Water retention curves of soils were obtained as the average of replications per and using the Eijkelkamp Sand and Sand/Kaolin suction tables (0-500 hPa) and a Decagon's WP4-T dewpoint potentiometer (0-300•106 hPa). The latest was used to determine the residual water content. Experimental water retention curves were to two different models: van Genuchten (1980) and Kosugi (1994). Once modeling was done, the slope value of the curves at the inflexion point, proposed by Dexter (2004a, b, c) to estimate physical quality of soils, was calculated. This study presents and discusses the advantages and problems of the different approaches for determining the water retention curves, the potential of these curves to evaluate physical modifications of the soils, and compares them with the other soil properties measured at the experiments. References: Dexter, A. R. 2004. a.- Soil physical quality. Part I. Theory, effects of soil texture, density, and organic matter, and effects on root growth. Geoderma 120 (2004) 201-214. Dexter, A. R. 2004. b.- Soil physical quality. Part II. Friability, tillage, tilth and hardsetting. Geoderma 120 (2004) 215-225. Dexter, A. R. 2004. c.- Soil physical quality. Part III: Unsaturated hydraulic conductivity and general conclusions about S-theory. Geoderma 120 (2004) 227-239. Kosugi, K. 1994. Three-parameter lognormal distribution model for soil water retention. Water Resour. Re. 30: 891-901. van Genutchen, M.Th. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils, Soil Science Society of America Journal, v.44, p.892-898,1980.

Performance Evaluation of the ONR Axial Waterjet 2 (AxWJ-2)

DTIC Science & Technology

2009-12-01

regions of the blade wakes and near the wall. Pump curves In order to estimate the uncertainty on the measured pump performance, it was first necessary to...velocity well outside the hub wake , but the tangential velocity magnitude and the axial velocity wake deficit are overpredicted near the hub. The...of these plots consists of a grid of 55 * 1024 points. In all three plots, the low-velocity regions six blade wakes are clearly visible, as are the

Managing Data From Signal-Propagation Experiments

NASA Technical Reports Server (NTRS)

Kantak, A. V.

1989-01-01

Computer programs generate characteristic plots from amplitudes and phases. Software system enables minicomputer to process data on amplitudes and phases of signals received during experiments in ground-mobile/satellite radio propagation. Takes advantage of file-handling capabilities of UNIX operating system and C programming language. Interacts with user, under whose guidance programs in FORTRAN language generate plots of spectra or other curves of types commonly used to characterize signals. FORTRAN programs used to process file-handling outputs into any of several useful forms.

Fire Suppression Testing of Hypergolic Vapor Control Foams

DTIC Science & Technology

1990-11-01

tests is given in Table 4. The obstruction test is plotted in Figure 11. c. MIL - F - 24385 -C Tests The low-expansion test utilized in certifying foams for...nozzle, and foam application in accordance with MIL - F -24385C. Extinguishment times were obtained for different application rates. The data were plotted...additional fire tests on the MMH curve. c. MIL - F -24385C Tests A second test (Test A-1B) of this type was conducted with the acrylic-modified foam using

Use of recurrence plot and recurrence quantification analysis in Taiwan unemployment rate time series

NASA Astrophysics Data System (ADS)

Chen, Wei-Shing

2011-04-01

The aim of the article is to answer the question if the Taiwan unemployment rate dynamics is generated by a non-linear deterministic dynamic process. This paper applies a recurrence plot and recurrence quantification approach based on the analysis of non-stationary hidden transition patterns of the unemployment rate of Taiwan. The case study uses the time series data of the Taiwan’s unemployment rate during the period from 1978/01 to 2010/06. The results show that recurrence techniques are able to identify various phases in the evolution of unemployment transition in Taiwan.

Teen Series' Reception: Television, Adolescence and Culture of Feelings.

ERIC Educational Resources Information Center

Pasquier, Dominique

1996-01-01

Noting the popularity of television teen series among young viewers in France, this study examined how the programs are used as a way of defining gender identity for children and adolescents. Results indicated construction of meanings of characters and plots varied by age, gender, and social background of viewers. Relationship to series relied on…

Rainfall-induced release of microbes from manure: model development, parameter estimation, and uncertainty evaluation on small plots

EPA Science Inventory

A series of simulated rainfall run-off experiments with applications of different manure types (cattle solid pats, poultry dry litter, swine slurry) was conducted across four seasons on a field containing 36 plots (0.75 × 2 m each), resulting in 144 rainfall run-off events....

Low-flow frequency curves for selected long-term stream gaging stations in eastern United States

USGS Publications Warehouse

Hardison, Clayton H.; Martin, Robert O.R.

1963-01-01

Curves showing the magnitude and frequency of annual low flow at 85 streamgaging stations located in 17 States east and 5 States west of the Mississippi River have been smoothed and adjusted to one of four long-term periods. They are presented to show the similarity and dissimilarity of curves even in the same State and to provide background information for studies of the statistical properties of low-flow frequency curves and for studies of the relation between hydrologic environment and low flow. The results are presented as greatly reduced graphs to facilitate comparison and are summarized in tables from which expanded graphs can be plotted.

Three-dimensional reconstruction of single-cell chromosome structure using recurrence plots.

PubMed

Hirata, Yoshito; Oda, Arisa; Ohta, Kunihiro; Aihara, Kazuyuki

2016-10-11

Single-cell analysis of the three-dimensional (3D) chromosome structure can reveal cell-to-cell variability in genome activities. Here, we propose to apply recurrence plots, a mathematical method of nonlinear time series analysis, to reconstruct the 3D chromosome structure of a single cell based on information of chromosomal contacts from genome-wide chromosome conformation capture (Hi-C) data. This recurrence plot-based reconstruction (RPR) method enables rapid reconstruction of a unique structure in single cells, even from incomplete Hi-C information.

Three-dimensional reconstruction of single-cell chromosome structure using recurrence plots

NASA Astrophysics Data System (ADS)

Hirata, Yoshito; Oda, Arisa; Ohta, Kunihiro; Aihara, Kazuyuki

2016-10-01

Single-cell analysis of the three-dimensional (3D) chromosome structure can reveal cell-to-cell variability in genome activities. Here, we propose to apply recurrence plots, a mathematical method of nonlinear time series analysis, to reconstruct the 3D chromosome structure of a single cell based on information of chromosomal contacts from genome-wide chromosome conformation capture (Hi-C) data. This recurrence plot-based reconstruction (RPR) method enables rapid reconstruction of a unique structure in single cells, even from incomplete Hi-C information.

Contribution of first- versus second-generation products to secondary organic aerosols formed in the oxidation of biogenic hydrocarbons.

PubMed

Ng, Nga L; Kroll, Jesse H; Keywood, Melita D; Bahreini, Roya; Varutbangkul, Varuntida; Flagan, Richard C; Seinfeld, John H; Lee, Anita; Goldstein, Allen H

2006-04-01

Biogenic hydrocarbons emitted by vegetation are important contributors to secondary organic aerosol (SOA), but the aerosol formation mechanisms are incompletely understood. In this study, the formation of aerosols and gas-phase products from the ozonolysis and photooxidation of a series of biogenic hydrocarbons (isoprene, 8 monoterpenes, 4 sesquiterpenes, and 3 oxygenated terpenes) are examined. By comparing aerosol growth (measured by Differential Mobility Analyzers, DMAs) and gas-phase concentrations (monitored by a Proton Transfer Reaction Mass Spectrometer, PTR-MS), we study the general mechanisms of SOA formation. Aerosol growth data are presented in terms of a "growth curve", a plot of aerosol mass formed versus the amount of hydrocarbon reacted. From the shapes of the growth curves, it is found that all the hydrocarbons studied can be classified into two groups based entirely on the number of double bonds of the hydrocarbon, regardless of the reaction systems (ozonolysis or photooxidation) and the types of hydrocarbons studied: compounds with only one double bond and compounds with more than one double bond. For compounds with only one double bond, the first oxidation step is rate-limiting, and aerosols are formed mainly from low volatility first-generation oxidation products; whereas for compounds with more than one double bond, the second oxidation step may also be rate-limiting and second-generation products contribute substantially to SOA growth. This behavior is characterized by a vertical section in the growth curve, in which continued aerosol growth is observed even after all the parent hydrocarbon is consumed.

SU-F-T-171: Manufacturing Cost Effective Heterogeneous Phantoms for Use in Proton Therapy

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

Pruett, J; Chen, Y; Ahmad, S

Purpose: To study the feasibility of 3D printing cost effective heterogeneous phantoms for use in proton therapy treatment planning quality assurance. Methods: A desktop 3D printer was utilized to create a series of 2 cm × 2 cm × 4 cm PLA plastic blocks of varying fill materials and hexagonal fill pattern. The blocks were than tested when filled with air, polyurethane foam, paraffin, silicone, and caulk of calcium carbonate – acrylic polymer blend. The blocks were evaluated with a “GE Lightspeed” 16 slice CT scanner and average CT# of the materials’ centers evaluated. Blocks were then placed into amore » custom aperture fitted to a Mevion Proton system to determine the relative stopping power of each. Scans were performed in water tank with Marcus type parallel plate chamber under a beam with a range of 15 cm and modulation of 2 cm. Shifts in range occurring relative to the 80% distal edge of the open SOBP were evaluated. Results: The CT#s of the blocks were plotted against their measured relative stopping power. This curve was compared to that which is in clinical use. While the trend agrees generally, specific differences between the relative stopping powers were as great as 10%. Conclusion: We have demonstrated that it is possible to utilize different cost effective materials in the manufacturing of phantoms for use in proton therapy. While different materials may provide better agreement to established calibration curves, a custom curve specific to the materials used may be utilized to accurately predict proton treatment dose distributions.« less

Effects of experimental design on calibration curve precision in routine analysis

PubMed Central

Pimentel, Maria Fernanda; Neto, Benício de Barros; Saldanha, Teresa Cristina B.

1998-01-01

A computational program which compares the effciencies of different experimental designs with those of maximum precision (D-optimized designs) is described. The program produces confidence interval plots for a calibration curve and provides information about the number of standard solutions, concentration levels and suitable concentration ranges to achieve an optimum calibration. Some examples of the application of this novel computational program are given, using both simulated and real data. PMID:18924816

[Age index and an interpretation of survivorship curves (author's transl)].

PubMed

Lohmann, W

1977-01-01

Clinical investigations showed that the age dependences of physiological functions do not show -- as generally assumed -- a linear increase with age, but an exponential one. Considering this result one can easily interpret the survivorship curve of a population (Gompertz plot). The only thing that is required is that the probability of death (death rate) is proportional to a function of ageing given by mu(t) = mu0 exp (alpha t). Considering survivorship curves resulting from annual death statistics and fitting them by suitable parameters, then the resulting alpha-values are in agreement with clinical data.

Kinematic Methods of Designing Free Form Shells

NASA Astrophysics Data System (ADS)

Korotkiy, V. A.; Khmarova, L. I.

2017-11-01

The geometrical shell model is formed in light of the set requirements expressed through surface parameters. The shell is modelled using the kinematic method according to which the shell is formed as a continuous one-parameter set of curves. The authors offer a kinematic method based on the use of second-order curves with a variable eccentricity as a form-making element. Additional guiding ruled surfaces are used to control the designed surface form. The authors made a software application enabling to plot a second-order curve specified by a random set of five coplanar points and tangents.

Shaped superconductor cylinder retains intense magnetic field

NASA Technical Reports Server (NTRS)

Hildebrandt, A. F.; Wahlquist, H.

1964-01-01

The curve of the inner walls of a superconducting cylinder is plotted from the flux lines of the magnetic field to be contained. This shaping reduces maximum flux densities and permits a stronger and more uniform magnetic field.

Aerodynamic method for obtaining the soil water retention curve

NASA Astrophysics Data System (ADS)

Alekseev, V. V.; Maksimov, I. I.

2013-07-01

A new method for the rapid plotting of the soil water retention curve (SWRC) has been proposed that considers the soil water as an environment limited by the soil solid phase on one side and by the soil air on the other side. Both contact surfaces have surface energies, which play the main role in water retention. The use of an idealized soil model with consideration for the nonequilibrium thermodynamic laws and the aerodynamic similarity principles allows us to estimate the volumetric specific surface areas of soils and, using the proposed pedotransfer function (PTF), to plot the SWRC. The volumetric specific surface area of the solid phase, the porosity, and the specific free surface energy at the water-air interface are used as the SWRC parameters. Devices for measuring the parameters are briefly described. The differences between the proposed PTF and the experimental data have been analyzed using the statistical processing of the data.

Analysis of LDPE-ZnO-clay nanocomposites using novel cumulative rheological parameters

NASA Astrophysics Data System (ADS)

Kracalik, Milan

2017-05-01

Polymer nanocomposites exhibit complex rheological behaviour due to physical and also possibly chemical interactions between individual phases. Up to now, rheology of dispersive polymer systems has been usually described by evaluation of viscosity curve (shear thinning phenomenon), storage modulus curve (formation of secondary plateau) or plotting information about dumping behaviour (e.g. Van Gurp-Palmen-plot, comparison of loss factor tan δ). On the contrary to evaluation of damping behaviour, values of cot δ were calculated and called as "storage factor", analogically to loss factor. Then values of storage factor were integrated over specific frequency range and called as "cumulative storage factor". In this contribution, LDPE-ZnO-clay nanocomposites with different dispersion grades (physical networks) have been prepared and characterized by both conventional as well as novel analysis approach. Next to cumulative storage factor, further cumulative rheological parameters like cumulative complex viscosity, cumulative complex modulus or cumulative storage modulus have been introduced.

Rheology of multiphase polymer systems using novel "melt rigidity" evaluation approach

NASA Astrophysics Data System (ADS)

Kracalik, Milan

2015-04-01

Multiphase polymer systems like blends, composites and nanocomposites exhibit complex rheological behaviour due to physical and also possibly chemical interactions between individual phases. Up to now, rheology of heterogeneous polymer systems has been usually described by evaluation of viscosity curve (shear thinning phenomenon), storage modulus curve (formation of secondary plateau) or plotting information about damping behaviour (e.g. Van Gurp-Palmen-plot). On the contrary to evaluation of damping behaviour, "melt rigidity" approach has been introduced for description of physical network of rigid particles in polymer matrix as relation of ∫G'/∫G" over specific frequency range. This approach has been experimentally proved for polymer nanocomposites in order to compare shear flow characteristics with elongational flow field. In this contribution, LDPE-clay nanocomposites with different dispersion grades (physical networks) have been prepared and characterized by both conventional as well as novel "melt rigidity" approach.

U-Th-Pb age of the Barwell chondrite - Anatomy of a 'discordant' meteorite

NASA Technical Reports Server (NTRS)

Unruh, D. M.; Tatsumoto, M.; Hutchison, R.

1979-01-01

A Pb-Pb internal isochron for the Barwell L5-6 chondrite yields an age of 4.530 plus or minus 0.005 billion years, using the measured U-238/U-235 ratio of 135.24 plus or minus .17. If the terrestrial U isotope composition is used, an age of 4.559 billion years is obtained. The Pb isotopic composition is distinctly different from that of a terrestrial contaminant found in the fusion crust of the Barwell stone. When the U-Th-Pb data are plotted on the concordia diagram, the data define a line that intersects the concordia curve at approximately 4.53 and 0 billion years, and nearly all of the data plot above the concordia curve, regardless of the initial Pb correction. This discordancy and the Pb isotopic composition of the triolite are attributed to a recent reequilibration of Pb and not to terrestrial contamination.

Evenly spaced Detrended Fluctuation Analysis: Selecting the number of points for the diffusion plot

NASA Astrophysics Data System (ADS)

Liddy, Joshua J.; Haddad, Jeffrey M.

2018-02-01

Detrended Fluctuation Analysis (DFA) has become a widely-used tool to examine the correlation structure of a time series and provided insights into neuromuscular health and disease states. As the popularity of utilizing DFA in the human behavioral sciences has grown, understanding its limitations and how to properly determine parameters is becoming increasingly important. DFA examines the correlation structure of variability in a time series by computing α, the slope of the log SD- log n diffusion plot. When using the traditional DFA algorithm, the timescales, n, are often selected as a set of integers between a minimum and maximum length based on the number of data points in the time series. This produces non-uniformly distributed values of n in logarithmic scale, which influences the estimation of α due to a disproportionate weighting of the long-timescale regions of the diffusion plot. Recently, the evenly spaced DFA and evenly spaced average DFA algorithms were introduced. Both algorithms compute α by selecting k points for the diffusion plot based on the minimum and maximum timescales of interest and improve the consistency of α estimates for simulated fractional Gaussian noise and fractional Brownian motion time series. Two issues that remain unaddressed are (1) how to select k and (2) whether the evenly-spaced DFA algorithms show similar benefits when assessing human behavioral data. We manipulated k and examined its effects on the accuracy, consistency, and confidence limits of α in simulated and experimental time series. We demonstrate that the accuracy and consistency of α are relatively unaffected by the selection of k. However, the confidence limits of α narrow as k increases, dramatically reducing measurement uncertainty for single trials. We provide guidelines for selecting k and discuss potential uses of the evenly spaced DFA algorithms when assessing human behavioral data.

Effects of weightlessness on human baroreflex function

NASA Technical Reports Server (NTRS)

Fritsch, Janice M.; Eckberg, Dwain L.

1992-01-01

Impaired cardiovascular function, characterized by orthostatic intolerance and reduced exercise capacity, is a result of space travel. We hypothesized that postflight baroreflex dysfunction may contribute. We studied the vagally mediated carotid baroreceptor-cardiac reflex response of 6 astronauts before, during, and after the ten day SLS-l mission. A series of R-waves triggered pressure and suction steps (from 40 to minus 65 mmHg) were delivered to a neck chamber during held expirtation. Resulting R-R interval changes were plotted against carotid distending pressure (systolic - neck pressure), and curve parameters calculated. After an initial rise, the operational point declined consistently during the flight and reached a nadir on landing day, but had recovered to preflight levels by L + 4. Slope and range of the response declined throughout the flight, were slightly recovered by the time measurements were made on landing day, but still were reduced on L + 4. These data indicate that space flight results in a significant impairment of the carotid baroreceptor cardiac reflex response.

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

Yan, Wei; Liu, Hongtao, E-mail: liuht100@126.com; Sun, Qinghe

A facile and quick fabrication method was proposed to prepare superhydrophobic surfaces on iron substrate by chemical immersion and subsequent stearic acid modification. The association between wettability and surface morphology was studied through altering the copper ion concentration and immersion time. Surface tension instrument, scanning electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and electrochemical workstation were used to characterize the wettability, physical morphology, chemical composition, and corrosion resistance ability of the prepared film. Results showed that both the rough micro/nanostructures and low surface energy material play critical roles in surface wettability. The superhydrophobic film achieved a better anticorrosion property comparedmore » to barrier iron by analysis of open circuit potential, potentiodynamic polarization curves, and Nyquist plots. In addition, the superhydrophobic surface showed excellent performance of acid and alkali resistance, anti-icing, and self-cleaning through a series of environmental tests. This study provides a valid method for quick-preparation of the stable superhydrophobic surfaces, which has a promising application in steel buildings and facilities.« less

Aerospace applications of sodium batteries using novel cathode materials

NASA Technical Reports Server (NTRS)

Ratnakumar, B. V.; Di Stefano, S.; Bankston, C. P.

1989-01-01

Preliminary fundamental investigations aimed at evaluating sodium metal chloride systems for future aerospace applications are described. Since the sodium metal chloride systems are relatively new, the approach has been to characterize their fundamental properties in order to understand their limitations. To this end, a series of fundamental electrochemical investigations have been carried out, the results of which are reported here. The metal chloride cathodes show high exchange current densities which corroborate their good reversibility in a battery application. The reduction mechanisms appear to be complex and involve multielectron transfer steps and intermediates. Such intermediates in the reaction mechanism have already been identified in the case of FeCl2. Similar mechanisms may be operative in the case of NiCl2. CuCl2, however, exhibits a second relaxation loop in the impedance plot at low frequencies and also a sloping discharge curve, unlike FeCl2 and NiCl2, which may indicate the existence of monovalent copper in the reduction mechanism.

SAHARA: A package of PC computer programs for estimating both log-hyperbolic grain-size parameters and standard moments

NASA Astrophysics Data System (ADS)

Christiansen, Christian; Hartmann, Daniel

This paper documents a package of menu-driven POLYPASCAL87 computer programs for handling grouped observations data from both sieving (increment data) and settling tube procedures (cumulative data). The package is designed deliberately for use on IBM-compatible personal computers. Two of the programs solve the numerical problem of determining the estimates of the four (main) parameters of the log-hyperbolic distribution and their derivatives. The package also contains a program for determining the mean, sorting, skewness. and kurtosis according to the standard moments. Moreover, the package contains procedures for smoothing and grouping of settling tube data. A graphic part of the package plots the data in a log-log plot together with the estimated log-hyperbolic curve. Along with the plot follows all estimated parameters. Another graphic option is a plot of the log-hyperbolic shape triangle with the (χ,ζ) position of the sample.

Net present value probability distributions from decline curve reserves estimates

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

Simpson, D.E.; Huffman, C.H.; Thompson, R.S.

1995-12-31

This paper demonstrates how reserves probability distributions can be used to develop net present value (NPV) distributions. NPV probability distributions were developed from the rate and reserves distributions presented in SPE 28333. This real data study used practicing engineer`s evaluations of production histories. Two approaches were examined to quantify portfolio risk. The first approach, the NPV Relative Risk Plot, compares the mean NPV with the NPV relative risk ratio for the portfolio. The relative risk ratio is the NPV standard deviation (a) divided the mean ({mu}) NPV. The second approach, a Risk - Return Plot, is a plot of themore » {mu} discounted cash flow rate of return (DCFROR) versus the {sigma} for the DCFROR distribution. This plot provides a risk-return relationship for comparing various portfolios. These methods may help evaluate property acquisition and divestiture alternatives and assess the relative risk of a suite of wells or fields for bank loans.« less

Testing and analysis of flat and curved panels with multiple cracks

DOT National Transportation Integrated Search

1994-08-01

An experimental and analytical investigation of multiple cracking in various types of test specimens is described in this paper. The testing phase is comprised of a flat unstiffened panel series and curved stiffened and unstiffened panel series. The ...

Decision curve analysis and external validation of the postoperative Karakiewicz nomogram for renal cell carcinoma based on a large single-center study cohort.

PubMed

Zastrow, Stefan; Brookman-May, Sabine; Cong, Thi Anh Phuong; Jurk, Stanislaw; von Bar, Immanuel; Novotny, Vladimir; Wirth, Manfred

2015-03-01

To predict outcome of patients with renal cell carcinoma (RCC) who undergo surgical therapy, risk models and nomograms are valuable tools. External validation on independent datasets is crucial for evaluating accuracy and generalizability of these models. The objective of the present study was to externally validate the postoperative nomogram developed by Karakiewicz et al. for prediction of cancer-specific survival. A total of 1,480 consecutive patients with a median follow-up of 82 months (IQR 46-128) were included into this analysis with 268 RCC-specific deaths. Nomogram-estimated survival probabilities were compared with survival probabilities of the actual cohort, and concordance indices were calculated. Calibration plots and decision curve analyses were used for evaluating calibration and clinical net benefit of the nomogram. Concordance between predictions of the nomogram and survival rates of the cohort was 0.911 after 12, 0.909 after 24 months and 0.896 after 60 months. Comparison of predicted probabilities and actual survival estimates with calibration plots showed an overestimation of tumor-specific survival based on nomogram predictions of high-risk patients, although calibration plots showed a reasonable calibration for probability ranges of interest. Decision curve analysis showed a positive net benefit of nomogram predictions for our patient cohort. The postoperative Karakiewicz nomogram provides a good concordance in this external cohort and is reasonably calibrated. It may overestimate tumor-specific survival in high-risk patients, which should be kept in mind when counseling patients. A positive net benefit of nomogram predictions was proven.

Uncertainty estimation with bias-correction for flow series based on rating curve

NASA Astrophysics Data System (ADS)

Shao, Quanxi; Lerat, Julien; Podger, Geoff; Dutta, Dushmanta

2014-03-01

Streamflow discharge constitutes one of the fundamental data required to perform water balance studies and develop hydrological models. A rating curve, designed based on a series of concurrent stage and discharge measurements at a gauging location, provides a way to generate complete discharge time series with a reasonable quality if sufficient measurement points are available. However, the associated uncertainty is frequently not available even though it has a significant impact on hydrological modelling. In this paper, we identify the discrepancy of the hydrographers' rating curves used to derive the historical discharge data series and proposed a modification by bias correction which is also in the form of power function as the traditional rating curve. In order to obtain the uncertainty estimation, we propose a further both-side Box-Cox transformation to stabilize the regression residuals as close to the normal distribution as possible, so that a proper uncertainty can be attached for the whole discharge series in the ensemble generation. We demonstrate the proposed method by applying it to the gauging stations in the Flinders and Gilbert rivers in north-west Queensland, Australia.

Rainfall-induced release of microbes from manure: model development, parameter estimation, and uncertainty evaluation on small plots

USDA-ARS?s Scientific Manuscript database

A series of simulated rainfall-runoff experiments with applications of different manure types (cattle solid pats, poultry dry litter, swine slurry) were conducted across four seasons on a field containing 36 plots (0.75 × 2 m each), resulting in 144 rainfall-runoff events. Simulating time-varying re...

Forest habitat types of northern Idaho: A second approximation

Treesearch

Stephen V. Cooper; Kenneth E. Neiman; David W. Roberts

1991-01-01

The addition of more than 900 plots to the Daubenmire's original 181-plot database has resulted in a refinement of their potential natural vegetation-based land classification for northern Idaho. A diagnostic, indicator species-based key is provided for field identification of the eight climax series, 46 habitat types, and 60 phases. Recognized syntaxa are...

Equations to assess the impact resistance of fiber composites

NASA Technical Reports Server (NTRS)

Chamis, C. C.; Hanson, M. P.; Serafini, T. T.

1972-01-01

Numerical analysis of impact resistance of composite materials containing fibers is discussed. Mathematical model of longitudinal impact resistance is presented. Potential impact resistance of various fiber composites as obtained by numerical analysis is presented as plotted curve.

The Computer Bulletin Board. Modified Gran Plots of Very Weak Acids on a Spreadsheet.

ERIC Educational Resources Information Center

Chau, F. T.; And Others

1990-01-01

Presented are two applications of computer technology to chemistry instruction: the use of a spreadsheet program to analyze acid-base titration curves and the use of database software to catalog stockroom inventories. (CW)

Real Data and Rapid Results: Ocean Color Data Analysis with Giovanni (GES DISC Interactive Online Visualization and ANalysis Infrastructure)

NASA Technical Reports Server (NTRS)

Acker, J. G.; Leptoukh, G.; Kempler, S.; Gregg, W.; Berrick, S.; Zhu, T.; Liu, Z.; Rui, H.; Shen, S.

2004-01-01

The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) has taken a major step addressing the challenge of using archived Earth Observing System (EOS) data for regional or global studies by developing an infrastructure with a World Wide Web interface which allows online, interactive, data analysis: the GES DISC Interactive Online Visualization and ANalysis Infrastructure, or "Giovanni." Giovanni provides a data analysis environment that is largely independent of underlying data file format. The Ocean Color Time-Series Project has created an initial implementation of Giovanni using monthly Standard Mapped Image (SMI) data products from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) mission. Giovanni users select geophysical parameters, and the geographical region and time period of interest. The system rapidly generates a graphical or ASCII numerical data output. Currently available output options are: Area plot (averaged or accumulated over any available data period for any rectangular area); Time plot (time series averaged over any rectangular area); Hovmeller plots (image view of any longitude-time and latitude-time cross sections); ASCII output for all plot types; and area plot animations. Future plans include correlation plots, output formats compatible with Geographical Information Systems (GIs), and higher temporal resolution data. The Ocean Color Time-Series Project will produce sensor-independent ocean color data beginning with the Coastal Zone Color Scanner (CZCS) mission and extending through SeaWiFS and Moderate Resolution Imaging Spectroradiometer (MODIS) data sets, and will enable incorporation of Visible/lnfrared Imaging Radiometer Suite (VIIRS) data, which will be added to Giovanni. The first phase of Giovanni will also include tutorials demonstrating the use of Giovanni and collaborative assistance in the development of research projects using the SeaWiFS and Ocean Color Time-Series Project data in the online Laboratory for Ocean Color Users (LOCUS). The synergy of Giovanni with high-quality ocean color data provides users with the ability to investigate a variety of important oceanic phenomena, such as coastal primary productivity related to pelagic fisheries, seasonal patterns and interannual variability, interdependence of atmospheric dust aerosols and harmful algal blooms, and the potential effects of climate change on oceanic productivity.

General-Purpose Software For Computer Graphics

NASA Technical Reports Server (NTRS)

Rogers, Joseph E.

1992-01-01

NASA Device Independent Graphics Library (NASADIG) is general-purpose computer-graphics package for computer-based engineering and management applications which gives opportunity to translate data into effective graphical displays for presentation. Features include two- and three-dimensional plotting, spline and polynomial interpolation, control of blanking of areas, multiple log and/or linear axes, control of legends and text, control of thicknesses of curves, and multiple text fonts. Included are subroutines for definition of areas and axes of plots; setup and display of text; blanking of areas; setup of style, interpolation, and plotting of lines; control of patterns and of shading of colors; control of legends, blocks of text, and characters; initialization of devices; and setting of mixed alphabets. Written in FORTRAN 77.

Lorenz curve of a light beam: evaluating beam quality from a majorization perspective.

PubMed

Porras, Miguel A; Gonzalo, Isabel; Ahmir Malik, M

2017-08-01

We introduce a novel approach for the characterization of the quality of a laser beam that is not based on particular criteria for beam width definition. The Lorenz curve of a light beam is a sophisticated version of the so-called power-in-the-bucket curve, formed by the partial sums of discretized joint intensity distribution in the near and far fields, sorted in decreasing order. According to majorization theory, a higher Lorenz curve implies that all measures of spreading in phase space, and, in particular, all Rényi (and Shannon) entropy-based measures of the beam width products in near and far fields, are unanimously smaller, providing a strong assessment of a better beam quality. Two beams whose Lorenz curves intersect can be considered of relatively better or lower quality only according to specific criteria, which can be inferred from the plot of the respective Lorenz curves.

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

Wackerbarth, David

Sandia National Laboratories has developed a computer program to review, reduce and manipulate waveform data. PlotData is designed for post-acquisition waveform data analysis. PlotData is both a post-acquisition and an advanced interactive data analysis environment. PlotData requires unidirectional waveform data with both uniform and discrete time-series measurements. PlotData operates on a National Instruments' LabVIEW™ software platform. Using PlotData, the user can capture waveform data from digitizing oscilloscopes over a GPIB, USB and Ethernet interface from Tektronix, Lecroy or Agilent scopes. PlotData can both import and export several types of binary waveform files including, but not limited to, Tektronix .wmf files,more » Lecroy.trc files and xy pair ASCIIfiles. Waveform manipulation includes numerous math functions, integration, differentiation, smoothing, truncation, and other specialized data reduction routines such as VISAR, POV, PVDF (Bauer) piezoelectric gauges, and piezoresistive gauges such as carbon manganin pressure gauges.« less

On representing the prognostic value of continuous gene expression biomarkers with the restricted mean survival curve.

PubMed

Eng, Kevin H; Schiller, Emily; Morrell, Kayla

2015-11-03

Researchers developing biomarkers for cancer prognosis from quantitative gene expression data are often faced with an odd methodological discrepancy: while Cox's proportional hazards model, the appropriate and popular technique, produces a continuous and relative risk score, it is hard to cast the estimate in clear clinical terms like median months of survival and percent of patients affected. To produce a familiar Kaplan-Meier plot, researchers commonly make the decision to dichotomize a continuous (often unimodal and symmetric) score. It is well known in the statistical literature that this procedure induces significant bias. We illustrate the liabilities of common techniques for categorizing a risk score and discuss alternative approaches. We promote the use of the restricted mean survival (RMS) and the corresponding RMS curve that may be thought of as an analog to the best fit line from simple linear regression. Continuous biomarker workflows should be modified to include the more rigorous statistical techniques and descriptive plots described in this article. All statistics discussed can be computed via standard functions in the Survival package of the R statistical programming language. Example R language code for the RMS curve is presented in the appendix.

Suppression tuning of distortion-product otoacoustic emissions: Results from cochlear mechanics simulation

PubMed Central

Liu, Yi-Wen; Neely, Stephen T.

2013-01-01

This paper presents the results of simulating the acoustic suppression of distortion-product otoacoustic emissions (DPOAEs) from a computer model of cochlear mechanics. A tone suppressor was introduced, causing the DPOAE level to decrease, and the decrement was plotted against an increasing suppressor level. Suppression threshold was estimated from the resulting suppression growth functions (SGFs), and suppression tuning curves (STCs) were obtained by plotting the suppression threshold as a function of suppressor frequency. Results show that the slope of SGFs is generally higher for low-frequency suppressors than high-frequency suppressors, resembling those obtained from normal hearing human ears. By comparing responses of normal (100%) vs reduced (50%) outer-hair-cell sensitivities, the model predicts that the tip-to-tail difference of the STCs correlates well with that of intra-cochlear iso-displacement tuning curves. The correlation is poorer, however, between the sharpness of the STCs and that of the intra-cochlear tuning curves. These results agree qualitatively with what was recently reported from normal-hearing and hearing-impaired human subjects, and examination of intra-cochlear model responses can provide the needed insight regarding the interpretation of DPOAE STCs obtained in individual ears. PMID:23363112

A Review of Correlated Noise in Exoplanet Light Curves

NASA Astrophysics Data System (ADS)

Cubillos, Patricio; Harrington, J.; Blecic, J.; Hardy, R. A.; Hardin, M.

2013-10-01

A number of the occultation light curves of exoplanets exhibit time-correlated residuals (a.k.a. correlated or red noise) in their model fits. The correlated noise might arise from inaccurate models or unaccounted astrophysical or telescope systematics. A correct assessment of the correlated noise is important to determine true signal-to-noise ratios of a planet's physical parameters. Yet, there are no in-depth statistical studies in the literature for some of the techniques currently used (RMS-vs-bin size plot, prayer beads, and wavelet-based modeling). We subjected these correlated-noise assessment techniques to basic tests on synthetic data sets to characterize their features and limitations. Initial results indicate, for example, that, sometimes the RMS-vs-bin size plots present artifacts when the bin size is similar to the observation duration. Further, the prayer beads doesn't correctly increase the uncertainties to compensate for the lack of accuracy if there is correlated noise. We have applied these techniques to several Spitzer secondary-eclipse hot-Jupiter light curves and discuss their implications. This work was supported in part by NASA planetary atmospheres grant NNX13AF38G and Astrophysics Data Analysis Program NNX12AI69G.

Saltation threshold on Mars - The effect of interparticle force, surface roughness, and low atmospheric density. [from wind-tunnel experiments

NASA Technical Reports Server (NTRS)

Iversen, J. D.; White, B. R.; Pollack, J. B.; Greeley, R.

1976-01-01

Results are reported for wind-tunnel experiments performed to determine the threshold friction speed of particles with different densities. Experimentally determined threshold speeds are plotted as a function of particle diameter and in terms of threshold parameter vs particle friction Reynolds number. The curves are compared with those of previous experiments, and an A-B curve is plotted to show differences in threshold speed due to differences in size distributions and particle shapes. Effects of particle diameter are investigated, an expression for threshold speed is derived by considering the equilibrium forces acting on a single particle, and other approximately valid expressions are evaluated. It is shown that the assumption of universality of the A-B curve is in error at very low pressures for small particles and that only predictions which take account of both Reynolds number and effects of interparticle forces yield reasonable agreement with experimental data. Effects of nonerodible surface roughness are examined, and threshold speeds computed with allowance for this factor are compared with experimental values. Threshold friction speeds on Mars are then estimated for a surface pressure of 5 mbar, taking into account all the factors considered.

Thio-arylglycosides with Various Aglycon Para-Substituents, a Probe for Studying Chemical Glycosylation Reactions

PubMed Central

Li, Xiaoning; Huang, Lijun; Hu, Xiche; Huang, Xuefei

2009-01-01

Summary Three series of thioglycosyl donors differing only in their respective aglycon substituents within each series have been prepared as representatives of typical glycosyl donors. The relative anomeric reactivities of these donors were quantified under competitive glycosylation conditions with various reaction time, promoters, solvents and acceptors. Over three orders of magnitude reactivity difference were generated by simple transformation of the para-substituent on the aglycon with methanol as the acceptor, while chemoselectivities became lower with carbohydrate acceptors. Excellent linear correlations were attained between relative reactivity values of donors and σp values of the substituents in the Hammett plots. This indicates that the glycosylation mechanism remains the same over a wide range of reactivities and glycosylation conditions. The negative slopes of the Hammett plots suggested that electron donating substituents expedite the reactions and the magnitudes of slopes can be rationalized by neighboring group participation as well as electronic properties of the glycon protective groups. Within the same series of donors, less nucleophilic acceptors gave smaller slopes in their Hammett plots. This is consistent with the notion that acceptor nucleophilic attack onto the reactive intermediate is part of the rate limiting step of the glycosylation reaction. Excellent linear Hammett correlations were obtained between relative reactivity values of three series of donors differing only in their aglycon substituents and σp values of the substituents. PMID:19081954

Data on fossil fuel availability for Shared Socioeconomic Pathways.

PubMed

Bauer, Nico; Hilaire, Jérôme; Brecha, Robert J; Edmonds, Jae; Jiang, Kejun; Kriegler, Elmar; Rogner, Hans-Holger; Sferra, Fabio

2017-02-01

The data files contain the assumptions and results for the construction of cumulative availability curves for coal, oil and gas for the five Shared Socioeconomic Pathways. The files include the maximum availability (also known as cumulative extraction cost curves) and the assumptions that are applied to construct the SSPs. The data is differentiated into twenty regions. The resulting cumulative availability curves are plotted and the aggregate data as well as cumulative availability curves are compared across SSPs. The methodology, the data sources and the assumptions are documented in a related article (N. Bauer, J. Hilaire, R.J. Brecha, J. Edmonds, K. Jiang, E. Kriegler, H.-H. Rogner, F. Sferra, 2016) [1] under DOI: http://dx.doi.org/10.1016/j.energy.2016.05.088.

Data development for ASTM E24.06.02 round robin program on instability prediction

NASA Technical Reports Server (NTRS)

Mccabe, D. E.

1979-01-01

Basis data for use in an ASTM E24.06.02 task group round robin activity was developed. Compact specimens were made of 2024-T351, 7075-T651 aluminum alloys, and 304 stainless steel. All were 12.7 mm thick and planar dimension variables incorporated were for 1T, 2T and 4T sizes. Representative raw data for each material and specimen size are contained herein. R-curves plotted in terms of delta a physical and delta a effective are plotted for each material.

Analysis of Coastal Sediment Transport Processes from Wrightsville Beach to Fort Fisher, North Carolina.

DTIC Science & Technology

1981-06-01

the erosional phase of beach behavior is the continual exposure of "fresh" beach sediment which may not have the approprixte sediment distribution...The time scale was reset to zero at the time of fill (t0O), and so the initial loss of beach fill after time t was St. Values of S (Fig. 19) for...varying time increments up to tt 1 were plotted on semilog paper. Figure 20 shows the results of these plots for the MLW, MSL, and NHW excursion curves

Control of tunnel barriers in multi-wall carbon nanotubes using focused ion beam irradiation

NASA Astrophysics Data System (ADS)

Tomizawa, H.; Suzuki, K.; Yamaguchi, T.; Akita, S.; Ishibashi, K.

2017-04-01

We have formed tunnel barriers in individual multi-wall carbon nanotubes using the Ga focused ion beam irradiation. The barrier height was estimated by the temperature dependence of the current (Arrhenius plot) and the current-voltage curves (Fowler-Nordheim plot). It is shown that the barrier height has a strong correlation with the barrier resistance that is controlled by the dose. Possible origins for the variation in observed barrier characteristics are discussed. Finally, the single electron transistor with two barriers is demonstrated.

A ∞-Algebra of an Elliptic Curve and Eisenstein Series

NASA Astrophysics Data System (ADS)

Polishchuk, Alexander

2011-02-01

We compute explicitly the A ∞-structure on the algebra {Ext^*(mathcal{O}_C oplus L, mathcal{O}_C oplus L)} , where L is a line bundle of degree 1 on an elliptic curve C. The answer involves higher derivatives of Eisenstein series.

Real-Time Series Resistance Monitoring in PV Systems Without the Need for I-V Curves

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

Deceglie, Michael G.; Silverman, Timothy J.; Marion, Bill

We apply the physical principles of a familiar method, suns-V oc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting I-V curves or constructing full series resistance-free I-V curves. RTSR is most readily deployable at the module level on microinverters or module-integrated electronics, but it can also be extended to full strings. We found that automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks,more » including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We also describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Real-Time Series Resistance Monitoring in PV Systems Without the Need for IV Curves

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

Deceglie, Michael G.; Silverman, Timothy J.; Marion, Bill

We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken soldermore » bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Analysis of the interests of Google users on toothache information.

PubMed

Lotto, Matheus; Ayala Aguirre, Patricia Estefania; Rios, Daniela; Andrade Moreira Machado, Maria Aparecida; Pereira Cruvinel, Agnes Fátima; Cruvinel, Thiago

2017-01-01

The knowledge on health interests of a given population of Internet users might contribute to the increase of evidence on community's dental needs, and consequently, to the improvement of public health planning. The frequency of searches for specific issues on Google can be analyzed by the application of Google Trends. In this study, we aimed to characterize the interests on toothache information of Google users from the United States, United Kingdom, Australia and Brazil. The monthly variation of relative search volume (RSV) and the lists of main toothache-related queries were determined from January 2004 through April 2016 using Google Trends. Autoregressive Integrated Moving Average (ARIMA) forecasting models were developed to determine predictive RSV values for toothache for additional 12 months. Autocorrelation plots and general additive model (GAM) were applied to determine trends and seasonality in RSV curves. Through linear regression models, we assessed the association between the variation of annual means of RSV values and national statistics for toothache in the U.S. and U.K. Subsequently, the distribution of main queries according to the identification of endodontic pain, type of searching information, and the interest in self-management of toothache was evaluated for the four countries. The autocorrelation plots showed patterns of non-stationary time series. The monthly variation influenced the data of the U.S. and U.K., with the higher RSV values found respectively in January/July and December. Also, the interest on toothache in the U.K. increases in the second semester and in the fourth quarter, especially in December. Additionally, an annual variation affected significantly all time series, with the increment of RSV means over the years, varying from 265% in the U.S. to 745% in Brazil. In parallel, the increments in RSV values were also observed in all predictive curves. The annual variation of observed and fitted RSV values was directly associated with the increase of toothache visits in the U.S. and urgent dental treatments in the U.K. Moreover, the queries typed on Google were markedly linked to searches on endodontic pain information, especially in Brazil, where the residents usually searched for relief and/or self-management of pain. Therefore, these findings indicate an increasing interest of Google users on toothache-related topics, regardless of country and season. The Internet activity can be used by policy makers as a complementary source of data for the development and implementation of strategies to control and prevent toothache complications.

Insights into soil carbon dynamics across climatic and geologic gradients from time-series and fraction-specific radiocarbon analysis

NASA Astrophysics Data System (ADS)

van der Voort, Tessa Sophia; Hagedorn, Frank; Zell, Claudia; McIntyre, Cameron; Eglinton, Tim

2016-04-01

Understanding the interaction between soil organic matter (SOM) and climatic, geologic and ecological factors is essential for the understanding of potential susceptibility and vulnerability to climate and land use change. Radiocarbon constitutes a powerful tool for unraveling SOM dynamics and is increasingly used in studies of carbon turnover. The complex and inherently heterogeneous nature of SOM renders it challenging to assess the processes that govern SOM stability by solely looking at the bulk signature on a plot-scale level. This project combines bulk radiocarbon measurements on a regional-scale spanning wide climatic and geologic gradients with a more in-depth approach for a subset of locations. For this subset, time-series and carbon pool-specific radiocarbon data has been acquired for both topsoil and deeper soils. These well-studied sites are part of the Long-Term Forest Ecosystem Research (LWF) program of the Swiss Federal Institute for Forest, Snow and Landscape research (WSL). Statistical analysis was performed to examine relationships of radiocarbon signatures with variables such as temperature, precipitation and elevation. Bomb-curve modeling was applied determine carbon turnover using time-series data. Results indicate that (1) there is no significant correlation between Δ14C signature and environmental conditions except a weak positive correlation with mean annual temperature, (2) vertical gradients in Δ14C signatures in surface and deeper soils are highly similar despite covering disparate soil-types and climatic systems, and (3) radiocarbon signatures vary significantly between time-series samples and carbon pools. Overall, this study provides a uniquely comprehensive dataset that allows for a better understanding of links between carbon dynamics and environmental settings, as well as for pool-specific and long-term trends in carbon (de)stabilization.

The NASA earth resources spectral information system: A data compilation, second supplement

NASA Technical Reports Server (NTRS)

Vincent, R. K.

1973-01-01

The NASA Earth Resources Spectral Information System (ERSIS) and the information contained therein are described. It is intended for use as a second supplement to the NASA Earth Resources Spectral Information System: A Data Compilation, NASA CR-31650-24-T, May 1971. The current supplement includes approximately 100 rock and mineral, and 375 vegetation directional reflectance spectral curves in the optical region from 0.2 to 22.0 microns. The data were categorized by subject and each curve plotted on a single graph. Each graph is fully titled to indicate curve source and indexed by subject to facilitate user retrieval from ERSIS magnetic tape records.

An Unusual Exponential Graph

ERIC Educational Resources Information Center

Syed, M. Qasim; Lovatt, Ian

2014-01-01

This paper is an addition to the series of papers on the exponential function begun by Albert Bartlett. In particular, we ask how the graph of the exponential function y = e[superscript -t/t] would appear if y were plotted versus ln t rather than the normal practice of plotting ln y versus t. In answering this question, we find a new way to…

An assessment of autumn olive in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2016-01-01

This publication is part of a series of research notes that provide an overview of the invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by...

US forests are showing increased rates of decline in response to a changing climate

Treesearch

Warren B. Cohen; Zhiqiang Yang; David M. Bell; Stephen V. Stehman

2015-01-01

How vulnerable are US forest to a changing climate? We answer this question using Landsat time series data and a unique interpretation approach, TimeSync, a plot-based Landsat visualization and data collection tool. Original analyses were based on a stratified two-stage cluster sample design that included interpretation of 3858 forested plots. From these data, we...

An assessment of nonnative bush honeysuckle in northern U.S. forests

Treesearch

Cassandra Kurtz; M.H. Hansen

2015-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by NRS...

Monitoring hemlock crown health in Delaware Water Gap National Recreation Area

Treesearch

Michael E. Montgomery; Bradley Onken; Richard A. Evans; Richard A. Evans

2005-01-01

Decline of the health of hemlocks in Delaware Water Gap National Recreation Area was noticeable in the southern areas of the park by 1992. The following year, a series of plots were established to monitor hemlock health and the abundance of hemlock woolly adelgid. This poster examines only the health rating of the hemlocks in the monitoring plots.

An assessment of common buckthorn in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2018-01-01

This publication is part of a series of that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by...

Early thinning experiments established by the Fort Valley Experimental Forest (P-53)

Treesearch

Benjamin P. De Blois; Alex. J. Finkral; Andrew J. Sánchez Meador; Margaret M. Moore

2008-01-01

Between 1925 and 1936, the Fort Valley Experimental Forest (FVEF) scientists initiated a study to examine a series of forest thinning experiments in second growth ponderosa pine stands in Arizona and New Mexico. These early thinning plots furnished much of the early background for the development of methods used in forest management in the Southwest. The plots ranged...

Early thinning experiments established by the Fort Valley Experimental Forest

Treesearch

Benjamin P. De Blois; Alex. J. Finkral; Andrew J. Sanchez Meador; Margaret M. Moore

2008-01-01

Between 1925 and 1936, the Fort Valley Experimental Forest (FVEF) scientists initiated a study to examine a series of forest thinning experiments in second growth ponderosa pine stands in Arizona and New Mexico. These early thinning plots furnished much of the early background for the development of methods used in forest management in the Southwest. The plots ranged...

An assessment of Japanese honeysuckle in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2015-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by NRS...

Harvesting intensity affects forest structure and composition in an upland Amazonian forest

Treesearch

John A. Parrotta; John K. Francis; Oliver H. Knowles; NO-VALUE

2002-01-01

Forest structure and floristic composition were studied in a series of 0.5 ha natural forest plots at four sites near Porto Trombetas in Pará State, Brazil, 11–12 years after being subjected to differing levels of above-ground biomass harvest and removal. In addition to undisturbed control plots, experimental treatments included: removal of...

An assessment of garlic mustard in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2014-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by FIA...

Assessment of trend and seasonality in road accident data: an Iranian case study.

PubMed

Razzaghi, Alireza; Bahrampour, Abbas; Baneshi, Mohammad Reza; Zolala, Farzaneh

2013-06-01

Road traffic accidents and their related deaths have become a major concern, particularly in developing countries. Iran has adopted a series of policies and interventions to control the high number of accidents occurring over the past few years. In this study we used a time series model to understand the trend of accidents, and ascertain the viability of applying ARIMA models on data from Taybad city. This study is a cross-sectional study. We used data from accidents occurring in Taybad between 2007 and 2011. We obtained the data from the Ministry of Health (MOH) and used the time series method with a time lag of one month. After plotting the trend, non-stationary data in mean and variance were removed using Box-Cox transformation and a differencing method respectively. The ACF and PACF plots were used to control the stationary situation. The traffic accidents in our study had an increasing trend over the five years of study. Based on ACF and PACF plots gained after applying Box-Cox transformation and differencing, data did not fit to a time series model. Therefore, neither ARIMA model nor seasonality were observed. Traffic accidents in Taybad have an upward trend. In addition, we expected either the AR model, MA model or ARIMA model to have a seasonal trend, yet this was not observed in this analysis. Several reasons may have contributed to this situation, such as uncertainty of the quality of data, weather changes, and behavioural factors that are not taken into account by time series analysis.

Detecting time-specific differences between temporal nonlinear curves: Analyzing data from the visual world paradigm

PubMed Central

Oleson, Jacob J; Cavanaugh, Joseph E; McMurray, Bob; Brown, Grant

2015-01-01

In multiple fields of study, time series measured at high frequencies are used to estimate population curves that describe the temporal evolution of some characteristic of interest. These curves are typically nonlinear, and the deviations of each series from the corresponding curve are highly autocorrelated. In this scenario, we propose a procedure to compare the response curves for different groups at specific points in time. The method involves fitting the curves, performing potentially hundreds of serially correlated tests, and appropriately adjusting the overall alpha level of the tests. Our motivating application comes from psycholinguistics and the visual world paradigm. We describe how the proposed technique can be adapted to compare fixation curves within subjects as well as between groups. Our results lead to conclusions beyond the scope of previous analyses. PMID:26400088

An empirical method for determining average soil infiltration rates and runoff, Powder River structural basin, Wyoming

USGS Publications Warehouse

Rankl, James G.

1982-01-01

This report describes a method to estimate infiltration rates of soils for use in estimating runoff from small basins. Average rainfall intensity is plotted against storm duration on log-log paper. All rainfall events are designated as having either runoff or nonrunoff. A power-decay-type curve is visually fitted to separate the two types of rainfall events. This separation curve is an incipient-ponding curve and its equation describes infiltration parameters for a soil. For basins with more than one soil complex, only the incipient-ponding curve for the soil complex with the lowest infiltration rate can be defined using the separation technique. Incipient-ponding curves for soils with infiltration rates greater than the lowest curve are defined by ranking the soils according to their relative permeabilities and optimizing the curve position. A comparison of results for six basins produced computed total runoff for all events used ranging from 16.6 percent less to 2.3 percent more than measured total runoff. (USGS)

Flood Control Project Lac Qui Parle, Emergency Plan

DTIC Science & Technology

1988-10-01

elevation of the breach (924.0 as shown in Table 1), is approximately 22.2 feet. The value of the envelope curve shown on Plate D-10 for a hydraulic...approximately 83% of the computed maximum outflow. Several failure scenarios for Lac qui Parle Dam were studied. The case of failure concurrent with a PKF ...discharge would plot very close to Lac qui Parle in Plate D-10. Plate D-10 shows that the value of the envelope curve for a hydraulic depth of 18.8 feet

Determining the Parameters of Fractional Exponential Hereditary Kernels for Nonlinear Viscoelastic Materials

NASA Astrophysics Data System (ADS)

Golub, V. P.; Pavlyuk, Ya. V.; Fernati, P. V.

2013-03-01

The parameters of fractional-exponential hereditary kernels for nonlinear viscoelastic materials are determined. Methods for determining the parameters used in the third-order theory of viscoelasticity and in nonlinear theories based on the similarity of primary creep curves and the similarity of isochronous creep curves are analyzed. The parameters of fractional-exponential hereditary kernels are determined and tested against experimental data for microplastic, TC-8/3-250 glass-reinforced plastics, SVAM glass-reinforced plastics. The results (tables and plots) are analyzed

Evaluation of production tests in oil wells stimulated by massive acid fracturing offshore Qatar

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

McDonald, S.W.

This paper presents the evaluation of pressure-buildup data from production tests in wells that have been stimulated by massive acid fracturing. Fracture type curves are used in combination with conventional semilog analysis techniques. Fracture characteristics are calculated from a match of the early-time pressure data with the type curves, and reservoir characteristics are calculated from a conventional semilog plot of late-time data. Unexpectedly high formation permeabilities are evaluated, and fracture half-lengths are much shorter than design values.

Relationships between antimicrobial effect and area under the concentration-time curve as a basis for comparison of modes of antibiotic administration: meropenem bolus injections versus continuous infusions.

PubMed Central

Firsov, A A; Mattie, H

1997-01-01

In comparative studies of different modes of administration (MAs) simulated in in vitro dynamic models, only one dose of antibiotic is usually mimicked. Such an experimental design can provide a prediction of the antimicrobial effect (AME) of a given combination of drug, clinical isolate, and infection site, but may be inappropriate for accurate comparison of MAs. An alternative design providing comparison of different MAs with various antibiotic doses in a wide range and with evaluation of the respective relationships between AME and the AUC was proposed and examined. Two series of meropenem pharmacokinetic profiles, i.e., monoexponentially decreasing concentrations (bolus doses) and constant concentrations (6-h continuous infusion), were in vitro simulated. The simulated initial concentrations (Co[from 0.62 to 48 micrograms/ml]) and steady-state concentrations (Css[from 0.016 to 8 micrograms/ml]) were chosen to provide similar AUC for 0 to 6 h (AUC0-6) ranges for both MAs (from 0.070 to 50.0 micrograms.h/ml and from 0.09 to 48.0 micrograms.h/ml, respectively). The AME of meropenem on Staphylococcus aureus ATCC 25923 (MIC, 0.06 micrograms/ml) was determined at each time (t) point as a difference (E) between the logarithms of viable counts (N) in the control cultures without antibiotic (NC) and in cultures exposed to antibiotics (NA). Time courses of E observed at different Co of Css levels were compared in terms of the areas under the E-t curves (ABBCt). The finite values of the ABBCt observed by the end of the 6 -h observation period, which are equivalent to the area between bacterial count-time curves observed in the absence and presence of antibiotic (ABBC), were plotted versus the respective AUCs produced by each of the MAs. The ABBC versus AUC curves had a similar pattern: a plateau achieved at high AUCs followed by a steep rise in ABBC at relatively low AUCs was inherent in both of the MAs. The superiority of bolus dosing over the infusions could be documented only for meropenem concentrations below the MIC. At higher Co or Css (i.e., at an AUC of > or = 0.4 micrograms.h/ml), the ABBC versus AUC curves plotted for each of the MAs could practically be superimposed. On the whole, both MAs appeared to be equiefficient in terms of the ABBC. These results suggest that AUC analysis of the AME may be a useful tool for comparing different MAs. Such comparative studies should be designed in a manner that provides the use of similar AUC ranges, since the AUC may be considered as a common pharmacokinetic denominator in comparing one MA or dosing regimen to another. PMID:9021191

ADMAP (automatic data manipulation program)

NASA Technical Reports Server (NTRS)

Mann, F. I.

1971-01-01

Instructions are presented on the use of ADMAP, (automatic data manipulation program) an aerospace data manipulation computer program. The program was developed to aid in processing, reducing, plotting, and publishing electric propulsion trajectory data generated by the low thrust optimization program, HILTOP. The program has the option of generating SC4020 electric plots, and therefore requires the SC4020 routines to be available at excution time (even if not used). Several general routines are present, including a cubic spline interpolation routine, electric plotter dash line drawing routine, and single parameter and double parameter sorting routines. Many routines are tailored for the manipulation and plotting of electric propulsion data, including an automatic scale selection routine, an automatic curve labelling routine, and an automatic graph titling routine. Data are accepted from either punched cards or magnetic tape.

Plutonium Critical Mass Curve Comparison to Mass at Upper Subcritical Limit (USL) Using Whisper

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

Alwin, Jennifer Louise; Zhang, Ning

Whisper is computational software designed to assist the nuclear criticality safety analyst with validation studies with the MCNP ® Monte Carlo radiation transport package. Standard approaches to validation rely on the selection of benchmarks based upon expert judgment. Whisper uses sensitivity/uncertainty (S/U) methods to select relevant benchmarks to a particular application or set of applications being analyzed. Using these benchmarks, Whisper computes a calculational margin. Whisper attempts to quantify the margin of subcriticality (MOS) from errors in software and uncertainties in nuclear data. The combination of the Whisper-derived calculational margin and MOS comprise the baseline upper subcritical limit (USL), tomore » which an additional margin may be applied by the nuclear criticality safety analyst as appropriate to ensure subcriticality. A series of critical mass curves for plutonium, similar to those found in Figure 31 of LA-10860-MS, have been generated using MCNP6.1.1 and the iterative parameter study software, WORM_Solver. The baseline USL for each of the data points of the curves was then computed using Whisper 1.1. The USL was then used to determine the equivalent mass for plutonium metal-water system. ANSI/ANS-8.1 states that it is acceptable to use handbook data, such as the data directly from the LA-10860-MS, as it is already considered validated (Section 4.3 4) “Use of subcritical limit data provided in ANSI/ANS standards or accepted reference publications does not require further validation.”). This paper attempts to take a novel approach to visualize traditional critical mass curves and allows comparison with the amount of mass for which the k eff is equal to the USL (calculational margin + margin of subcriticality). However, the intent is to plot the critical mass data along with USL, not to suggest that already accepted handbook data should have new and more rigorous requirements for validation.« less

Recurrence quantification analysis of heart rate variability and respiratory flow series in patients on weaning trials.

PubMed

Arcentales, Andrés; Giraldo, Beatriz F; Caminal, Pere; Benito, Salvador; Voss, Andreas

2011-01-01

Autonomic nervous system regulates the behavior of cardiac and respiratory systems. Its assessment during the ventilator weaning can provide information about physio-pathological imbalances. This work proposes a non linear analysis of the complexity of the heart rate variability (HRV) and breathing duration (T(Tot)) applying recurrence plot (RP) and their interaction joint recurrence plot (JRP). A total of 131 patients on weaning trials from mechanical ventilation were analyzed: 92 patients with successful weaning (group S) and 39 patients that failed to maintain spontaneous breathing (group F). The results show that parameters as determinism (DET), average diagonal line length (L), and entropy (ENTR), are statistically significant with RP for T(Tot) series, but not with HRV. When comparing the groups with JRP, all parameters have been relevant. In all cases, mean values of recurrence quantification analysis are higher in the group S than in the group F. The main differences between groups were found on the diagonal and vertical structures of the joint recurrence plot.

Digital geologic map of the Butler Peak 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Miller, Fred K.; Matti, Jonathan C.; Brown, Howard J.; digital preparation by Cossette, P. M.

2000-01-01

Open-File Report 00-145, is a digital geologic map database of the Butler Peak 7.5' quadrangle that includes (1) ARC/INFO (Environmental Systems Research Institute) version 7.2.1 Patch 1 coverages, and associated tables, (2) a Portable Document Format (.pdf) file of the Description of Map Units, Correlation of Map Units chart, and an explanation of symbols used on the map, btlrpk_dcmu.pdf, (3) a Portable Document Format file of this Readme, btlrpk_rme.pdf (the Readme is also included as an ascii file in the data package), and (4) a PostScript plot file of the map, Correlation of Map Units, and Description of Map Units on a single sheet, btlrpk.ps. No paper map is included in the Open-File report, but the PostScript plot file (number 4 above) can be used to produce one. The PostScript plot file generates a map, peripheral text, and diagrams in the editorial format of USGS Geologic Investigation Series (I-series) maps.

Errors in the estimation of approximate entropy and other recurrence-plot-derived indices due to the finite resolution of RR time series.

PubMed

García-González, Miguel A; Fernández-Chimeno, Mireya; Ramos-Castro, Juan

2009-02-01

An analysis of the errors due to the finite resolution of RR time series in the estimation of the approximate entropy (ApEn) is described. The quantification errors in the discrete RR time series produce considerable errors in the ApEn estimation (bias and variance) when the signal variability or the sampling frequency is low. Similar errors can be found in indices related to the quantification of recurrence plots. An easy way to calculate a figure of merit [the signal to resolution of the neighborhood ratio (SRN)] is proposed in order to predict when the bias in the indices could be high. When SRN is close to an integer value n, the bias is higher than when near n - 1/2 or n + 1/2. Moreover, if SRN is close to an integer value, the lower this value, the greater the bias is.

The Reassuring Role of TV's Continuing Characters.

ERIC Educational Resources Information Center

Piltch, Charles N.

1979-01-01

The author analyzes the series form of television program, particularly the qualities and functions of the continuing characters and their relationship to the plot. He discusses the reassuring psychological effects of a TV series on the audience and the implications of a decline in this type of programing. (SJL)

Mating Disruption for the 21st Century: Matching Technology With Mechanism.

PubMed

Miller, James R; Gut, Larry J

2015-06-01

Progress toward proof of the principal cause of insect mating disruption under a particular set of conditions has been hindered by a lack of logical rigor and clean falsifications of possible explanations. Here we make the case that understanding of mating disruption and optimization of particular formulations can be significantly advanced by rigorous application of the principles of strong inference. To that end, we offer a dichotomous key for eight distinct categories of mating disruption and detail criteria and methodologies for differentiating among them. Mechanisms of mating disruption closely align with those established for enzyme inhibition, falling into two major categories-competitive and noncompetitive. Under competitive disruption, no impairments are experienced by males, females, or the signal of females. Therefore, males can respond to females and traps. Competitive disruption is entirely a numbers game where the ratio of dispensers to females and traps is highly consequential and renders the control pest-density-dependent. Under noncompetitive disruption, males, females, or the signal from females are already impaired when sexual activity commences. The control achieved noncompetitively offers the notable advantage of being pest-density-independent. Dosage-response curves are the best way to distinguish competitive from noncompetitive disruption. Purely competitive disruption produces: a smoothly concave curve when untransformed capture data are plotted on the y-axis against density of dispensers on the x-axis; a straight line with positive slope when the inverse of catch is plotted against density of pheromone dispensers; and, a straight line with negative slope when catch is plotted against density of pheromone dispensers × catch. Disruption operating only noncompetitively produces: a straight line with negative slope when untransformed capture data are plotted on the y-axis against density of dispensers on the x-axis; an upturning curve when the inverse of catch is plotted against density of pheromone dispensers; and, a recurving plot when catch is plotted against density of pheromone dispensers x catch. Hybrid profiles are possible when some males within the population begin the activity period already incapacitated, while those not preexposed have the capacity to respond either to traps or pheromone dispensers. Competitive mechanisms include competitive attraction, induced allopatry, and induced arrestment. Noncompetitive mechanisms include desensitization and inhibition, induced allochrony, suppressed calling and mating, camouflage, and sensory imbalance. Examples of the various disruption types within the two major categories and suggested tactics for differentiating among them are offered as seven case studies of the disruption of important pest species using various formulations are analyzed in depth. We point out how economic optimizations may be achieved once the principal and contributory causes of disruption are proven. Hopefully, these insights will pave the way to a broader and more reliable usage of this environmentally friendly pest management tactic. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An historically consistent and broadly applicable MRV system based on LiDAR sampling and Landsat time-series

Treesearch

W. Cohen; H. Andersen; S. Healey; G. Moisen; T. Schroeder; C. Woodall; G. Domke; Z. Yang; S. Stehman; R. Kennedy; C. Woodcock; Z. Zhu; J. Vogelmann; D. Steinwand; C. Huang

2014-01-01

The authors are developing a REDD+ MRV system that tests different biomass estimation frameworks and components. Design-based inference from a costly fi eld plot network was compared to sampling with LiDAR strips and a smaller set of plots in combination with Landsat for disturbance monitoring. Biomass estimation uncertainties associated with these different data sets...

Red spruce ecosystem level changes following 14 years of chronic N fertilization

Treesearch

Steven G. McNulty; Johnny Boggs; John D. Aber; Lindsey Rustad; Allison Magill

2005-01-01

In the early 1980s, nitrogen (N) deposition was first postulated as a cause of N saturation and spruce mortality across the northeastern US. In 1988, a series of high elevation spruce-fir forest N addition plots were established on Mt. Ascutney (southeastern) Vermont to test this hypothesis. The paired plots each received, in addition to ambient N deposition, 15.7 kg...

Sensitivity curves for searches for gravitational-wave backgrounds

NASA Astrophysics Data System (ADS)

Thrane, Eric; Romano, Joseph D.

2013-12-01

We propose a graphical representation of detector sensitivity curves for stochastic gravitational-wave backgrounds that takes into account the increase in sensitivity that comes from integrating over frequency in addition to integrating over time. This method is valid for backgrounds that have a power-law spectrum in the analysis band. We call these graphs “power-law integrated curves.” For simplicity, we consider cross-correlation searches for unpolarized and isotropic stochastic backgrounds using two or more detectors. We apply our method to construct power-law integrated sensitivity curves for second-generation ground-based detectors such as Advanced LIGO, space-based detectors such as LISA and the Big Bang Observer, and timing residuals from a pulsar timing array. The code used to produce these plots is available at https://dcc.ligo.org/LIGO-P1300115/public for researchers interested in constructing similar sensitivity curves.

Product differentiation by analysis of DNA melting curves during the polymerase chain reaction.

PubMed

Ririe, K M; Rasmussen, R P; Wittwer, C T

1997-02-15

A microvolume fluorometer integrated with a thermal cycler was used to acquire DNA melting curves during polymerase chain reaction by fluorescence monitoring of the double-stranded DNA specific dye SYBR Green I. Plotting fluorescence as a function of temperature as the thermal cycler heats through the dissociation temperature of the product gives a DNA melting curve. The shape and position of this DNA melting curve are functions of the GC/AT ratio, length, and sequence and can be used to differentiate amplification products separated by less than 2 degrees C in melting temperature. Desired products can be distinguished from undesirable products, in many cases eliminating the need for gel electrophoresis. Analysis of melting curves can extend the dynamic range of initial template quantification when amplification is monitored with double-stranded DNA specific dyes. Complete amplification and analysis of products can be performed in less than 15 min.

Tensile and pack compressive tests of some sheets of aluminum alloy, 1025 carbon steel, and chromium-nickel steel

NASA Technical Reports Server (NTRS)

Atchison, C S; Miller, James A

1942-01-01

Tensile and compressive stress-strain curves, stress-deviation curves, and secant modulus-stress curves are given for longitudinal and transverse specimens of 17S-T, 24S-T, and 24S-RT aluminum-alloy sheet in thicknesses from 0.032 to 0.081 inch, 1025 carbon steel sheet in thicknesses of 0.054 and 0.120 inch, and chromium-nickel steel sheet in thicknesses form 0.020 to 0.0275 inch. Significant differences were found between the tensile and the compressive stress-strain curves, and also the corresponding corollary curves; similarly, differences were found between the curves for the longitudinal and transverse directions. These differences are of particular importance in considering the compressive strength of aircraft structures made of thin sheet. They are explored further for the case of compression by giving tangent modulus-stress curves in longitudinal and transverse compression and dimensionless curves of the ratio of tangent modulus to Young's modulus and of the ratio of reduced modulus for a rectangular section to Young's modulus, both plotted against the ratio of stress to secant yield strength.

Use of the AAVSO's International Variable Star Index (VSX) in an Undergraduate Astronomy Course Capstone Project

NASA Astrophysics Data System (ADS)

Larsen, Kristine

2017-06-01

The author discusses a capstone project that utilizes the AAVSO's International Variable Star Index (VSX), ASAS light curves and phase plots, and the SIMBAD astronomical data repository in a laboratory-based undergraduate Stellar and Galactic Astronomy course.

Effect of DNA-injuring agents on B. stearothermophilus. Report 1. High resistance of B. stearothermophilus to N-nitroso-N-methylurea, ultraviolet and gamma radiation

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

Gainullina, S.M.; Gumanova, A.V.; Vinogradova, N.A.

1978-01-01

The effects of DNA-attacking agents on thermophilic microorganisms were investigated. Bacillus stearothermophilus were treated with N-nitroso-N-methylurea, ultraviolet radiation or gamma radiation. Survival curves were plotted.

Nonlinear Circuit Concepts -- An Elementary Experiment.

ERIC Educational Resources Information Center

Matolyak, J.; And Others

1983-01-01

Describes equipment and procedures for an experiment using diodes to introduce non-linear electronic devices in a freshman physics laboratory. The experiment involves calculation and plotting of the characteristic-curve and load-line to predict the operating point and compare prediction to experimentally determined values. Background information…

Detecting recurrence domains of dynamical systems by symbolic dynamics.

PubMed

beim Graben, Peter; Hutt, Axel

2013-04-12

We propose an algorithm for the detection of recurrence domains of complex dynamical systems from time series. Our approach exploits the characteristic checkerboard texture of recurrence domains exhibited in recurrence plots. In phase space, recurrence plots yield intersecting balls around sampling points that could be merged into cells of a phase space partition. We construct this partition by a rewriting grammar applied to the symbolic dynamics of time indices. A maximum entropy principle defines the optimal size of intersecting balls. The final application to high-dimensional brain signals yields an optimal symbolic recurrence plot revealing functional components of the signal.

A mechanistic approach to studies of the possible digestion of retrograded starch by α-amylase revealed using a log of slope (LOS) plot

PubMed Central

Patel, Hamung; Day, Richard; Butterworth, Peter J.; Ellis, Peter R.

2014-01-01

The rate and extent of digestibility of starch were analysed using the logarithm of the slope (LOS) method. Digestibility curves with α-amylase were obtained for starches in their native, gelatinised and 24 h retrograded form. A LOS plot of the digestibility curves was then constructed, which allowed the rate constant (k) and the concentration of the product at the end of the reaction (C∞) to be calculated. It also allowed the identification of rapid and slow phases in starch digestion. Upon gelatinisation, both k and C∞ increased with dramatic changes notably in C∞; however after starch samples had been stored for 24 h at room temperature, k was not affected but C∞ decreased. This suggests that retrograded starch is virtually inert to amylase action. Both k and C∞ were strongly related to the increase in degree of order of the α-glucan chains, monitored by FTIR-ATR spectroscopy, in retrograded starch. PMID:25256473

Refactoring DIRT

NASA Astrophysics Data System (ADS)

Amarnath, N. S.; Pound, M. W.; Wolfire, M. G.

The Dust InfraRed ToolBox (DIRT - a part of the Web Infrared ToolShed, or WITS, located at http://dustem.astro.umd.edu) is a Java applet for modeling astrophysical processes in circumstellar shells around young and evolved stars. DIRT has been used by the astrophysics community for about 4 years. DIRT uses results from a number of numerical models of astrophysical processes, and has an AWT based user interface. DIRT has been refactored to decouple data representation from plotting and curve fitting. This makes it easier to add new kinds of astrophysical models, use the plotter in other applications, migrate the user interface to Swing components, and modify the user interface to add functionality (for example, SIRTF tools). DIRT is now an extension of two generic libraries, one of which manages data representation and caching, and the second of which manages plotting and curve fitting. This project is an example of refactoring with no impact on user interface, so the existing user community was not affected.

Presenting simulation results in a nested loop plot.

PubMed

Rücker, Gerta; Schwarzer, Guido

2014-12-12

Statisticians investigate new methods in simulations to evaluate their properties for future real data applications. Results are often presented in a number of figures, e.g., Trellis plots. We had conducted a simulation study on six statistical methods for estimating the treatment effect in binary outcome meta-analyses, where selection bias (e.g., publication bias) was suspected because of apparent funnel plot asymmetry. We varied five simulation parameters: true treatment effect, extent of selection, event proportion in control group, heterogeneity parameter, and number of studies in meta-analysis. In combination, this yielded a total number of 768 scenarios. To present all results using Trellis plots, 12 figures were needed. Choosing bias as criterion of interest, we present a 'nested loop plot', a diagram type that aims to have all simulation results in one plot. The idea was to bring all scenarios into a lexicographical order and arrange them consecutively on the horizontal axis of a plot, whereas the treatment effect estimate is presented on the vertical axis. The plot illustrates how parameters simultaneously influenced the estimate. It can be combined with a Trellis plot in a so-called hybrid plot. Nested loop plots may also be applied to other criteria such as the variance of estimation. The nested loop plot, similar to a time series graph, summarizes all information about the results of a simulation study with respect to a chosen criterion in one picture and provides a suitable alternative or an addition to Trellis plots.

Systematics of Rydberg Series of Diatomic Molecules and Correlation Diagrams

NASA Astrophysics Data System (ADS)

Lee, Chun-Woo

2015-06-01

Rydberg states are studied for H2, Li2, HeH, LiH and BeH using the multi-reference configuration interaction (MRCI) method. The systematics and regularities of the physical properties such as potential energies curves (PECs), quantum defect curves, permanent dipole moment and transition dipole moment curves of the Rydberg series are studied. They are explained using united atom perturbation theory by Bingel and Byers-Brown, Fermi model, Stark theory, and Mulliken's theory. Interesting mirror relationships of the dipole moments are observed between l-mixed Rydberg series, indicating that the members of the l-mixed Rydberg series have dipole moments with opposite directions, which are related to the reversal of the polarity of a dipole moment at the avoided crossing points. The assignment of highly excited states is difficult because of the usual absence of the knowledge on the behaviors of potential energy curves at small internuclear separation whereby the correlation between the united atom limit and separated atoms limit cannot be given. All electron MRCI calculations of PECs are performed to obtain the correlation diagrams between Rydberg orbitals at the united-atom and separated atoms limits.

Diversity of Hymenoptera (Insecta) on different ages of oil palm in Lekir Plantation, Perak

NASA Astrophysics Data System (ADS)

Azhari, Muhammad Luqman Hakim; Hazmi, Izfa Riza

2018-04-01

This study was conducted to determine the diversity of Hymenoptera on the different ages of oil palm namely plot 12, 9 and 5 years old. Sampling was carried out from November 2015 to February 2016 at Ladang Lekir, Perak using Malaise traps and Window trap. A total of 3052 individuals Hymenopteran consisting of 58 morphospecies and 35 subfamilies of 17 families were successfully collected. The most abundant species recorded was the Pimplinae.sp4 with 447 individuals (relative abundance, RA=14.51%). According to the plot, plot 9 years old have the highest reading for all three Peilou Equality Index (E'=0.983), Shannon Diversity Index (H'=3.939) and Simpson Diversity Index (D'=0.9795) with 55 species have been recorded. The t-tests showed that there were no significant difference in term of the diversity index (H') between palm plots 9 years old and 12 years old, while there were significant differences between the two plot (9 years old and 12 years old) with 5 old palm plot. The species accumulation curve showed that only 5 old palm plot nearly asymptotic. This study is expected to help the management to provide basic information for future research and as well, to develop and implement tools, methods, strategies in farm management practices of the oil palm plantations in Malaysia.

The determination of ethanol in blood and urine by mass fragmentography

NASA Technical Reports Server (NTRS)

Pereira, W. E.; Summons, R. E.; Rindfleisch, T. C.; Duffield, A. M.

1974-01-01

A mass fragmentographic technique for a rapid, specific and sensitive determination of ethanol in blood and urine is described. A Varian gas chromatograph coupled through an all-glass membrane separator to a Finnigan quadripole mass spectrometer and interfaced to a computer system is used for ethanol determination in blood and urine samples. A procedure for plotting calibration curves for ethanol quantitation is also described. Quantitation is achieved by plotting the peak area ratios of undeuterated-to-deuterated ethanol fragment ions against the amount of ethanol added. Representative results obtained by this technique are included.

[A modification of the Gompertz plot resulting from the age index by Ries and an approximation of the survivorship curve (author's transl)].

PubMed

Lohmann, W

1978-01-01

The shape of the survivorship curve can easily be interpreted on condition that the probability of death is proportional to an exponentially rising function of ageing. According to the formation of a sum for determining of the age index by Ries it was investigated to what extent the survivorship curve may be approximated by a sum of exponentials. It follows that the difference between the pure exponential function and a sum of exponentials by using possible values is lying within the random variation. Because the probability of death for different diseases is variable, the new statement is a better one.

Study of Glycemic Variability Through Time Series Analyses (Detrended Fluctuation Analysis and Poincaré Plot) in Children and Adolescents with Type 1 Diabetes.

PubMed

García Maset, Leonor; González, Lidia Blasco; Furquet, Gonzalo Llop; Suay, Francisco Montes; Marco, Roberto Hernández

2016-11-01

Time series analysis provides information on blood glucose dynamics that is unattainable with conventional glycemic variability (GV) indices. To date, no studies have been published on these parameters in pediatric patients with type 1 diabetes. Our aim is to evaluate the relationship between time series analysis and conventional GV indices, and glycosylated hemoglobin (HbA1c) levels. This is a transversal study of 41 children and adolescents with type 1 diabetes. Glucose monitoring was carried out continuously for 72 h to study the following GV indices: standard deviation (SD) of glucose levels (mg/dL), coefficient of variation (%), interquartile range (IQR; mg/dL), mean amplitude of the largest glycemic excursions (MAGE), and continuous overlapping net glycemic action (CONGA). The time series analysis was conducted by means of detrended fluctuation analysis (DFA) and Poincaré plot. Time series parameters (DFA alpha coefficient and elements of the ellipse of the Poincaré plot) correlated well with the more conventional GV indices. Patients were grouped according to the terciles of these indices, to the terciles of eccentricity (1: 12.56-16.98, 2: 16.99-21.91, 3: 21.92-41.03), and to the value of the DFA alpha coefficient (> or ≤1.5). No differences were observed in the HbA1c of patients grouped by GV index criteria; however, significant differences were found in patients grouped by alpha coefficient and eccentricity, not only in terms of HbA1c, but also in SD glucose, IQR, and CONGA index. The loss of complexity in glycemic homeostasis is accompanied by an increase in variability.

Asteroid spectral reflectivities.

NASA Technical Reports Server (NTRS)

Chapman, C. R.; Mccord, T. B.; Johnson, T. V.

1973-01-01

We measured spectral reflectivities (0.3-1.1 micron) for 32 asteroids. There are at least 14 different curve types. Common types are: (a) reddish curves with 10% absorptions near 0.95 micron or beyond 1.0 micron, due to Fe(2+) in minerals such as pyroxenes; (b) flat curves in the visible and near-IR with sharp decreases in the UV and (c) flat curves even into the UV. Several asteroids show probable color variations with rotation, especially 6 Hebe. A sample of 102 asteroids with reliably known colors is derived from the reflectivities and from earlier colorimetry. Several correlations of colors and spectral curve types with orbital and physical parameters are examined: (1) asteroids with large aphelia have flat reflectivities while those with small perihelia are mostly reddish, (2) curve types show evidence for clustering on an a vs e plot, with 0.95 micron bands occuring mainly for Mars-approaching asteroids, (3) no strong correlation exists between color and either proper eccentricity or proper inclination.

Reevaluation of the Amsterdam Inventory for Auditory Disability and Handicap Using Item Response Theory.

PubMed

Boeschen Hospers, J Mirjam; Smits, Niels; Smits, Cas; Stam, Mariska; Terwee, Caroline B; Kramer, Sophia E

2016-04-01

We reevaluated the psychometric properties of the Amsterdam Inventory for Auditory Disability and Handicap (AIADH; Kramer, Kapteyn, Festen, & Tobi, 1995) using item response theory. Item response theory describes item functioning along an ability continuum. Cross-sectional data from 2,352 adults with and without hearing impairment, ages 18-70 years, were analyzed. They completed the AIADH in the web-based prospective cohort study "Netherlands Longitudinal Study on Hearing." A graded response model was fitted to the AIADH data. Category response curves, item information curves, and the standard error as a function of self-reported hearing ability were plotted. The graded response model showed a good fit. Item information curves were most reliable for adults who reported having hearing disability and less reliable for adults with normal hearing. The standard error plot showed that self-reported hearing ability is most reliably measured for adults reporting mild up to moderate hearing disability. This is one of the few item response theory studies on audiological self-reports. All AIADH items could be hierarchically placed on the self-reported hearing ability continuum, meaning they measure the same construct. This provides a promising basis for developing a clinically useful computerized adaptive test, where item selection adapts to the hearing ability of individuals, resulting in efficient assessment of hearing disability.

Automated Estimation of the Orbital Parameters of Jupiter's Moons

NASA Astrophysics Data System (ADS)

Western, Emma; Ruch, Gerald T.

2016-01-01

Every semester the Physics Department at the University of St. Thomas has the Physics 104 class complete a Jupiter lab. This involves taking around twenty images of Jupiter and its moons with the telescope at the University of St. Thomas Observatory over the course of a few nights. The students then take each image and find the distance from each moon to Jupiter and plot the distances versus the elapsed time for the corresponding image. Students use the plot to fit four sinusoidal curves of the moons of Jupiter. I created a script that automates this process for the professor. It takes the list of images and creates a region file used by the students to measure the distance from the moons to Jupiter, a png image that is the graph of all the data points and the fitted curves of the four moons, and a csv file that contains the list of images, the date and time each image was taken, the elapsed time since the first image, and the distances to Jupiter for Io, Europa, Ganymede, and Callisto. This is important because it lets the professor spend more time working with the students and answering questions as opposed to spending time fitting the curves of the moons on the graph, which can be time consuming.

Titration ELISA as a Method to Determine the Dissociation Constant of Receptor Ligand Interaction.

PubMed

Eble, Johannes A

2018-02-15

The dissociation constant describes the interaction between two partners in the binding equilibrium and is a measure of their affinity. It is a crucial parameter to compare different ligands, e.g., competitive inhibitors, protein isoforms and mutants, for their binding strength to a binding partner. Dissociation constants are determined by plotting concentrations of bound versus free ligand as binding curves. In contrast, titration curves, in which a signal that is proportional to the concentration of bound ligand is plotted against the total concentration of added ligand, are much easier to record. The signal can be detected spectroscopically and by enzyme-linked immunosorbent assay (ELISA). This is exemplified in a protocol for a titration ELISA that measures the binding of the snake venom-derived rhodocetin to its immobilized target domain of α2β1 integrin. Titration ELISAs are versatile and widely used. Any pair of interacting proteins can be used as immobilized receptor and soluble ligand, provided that both proteins are pure, and their concentrations are known. The difficulty so far has been to determine the dissociation constant from a titration curve. In this study, a mathematical function underlying titration curves is introduced. Without any error-prone graphical estimation of a saturation yield, this algorithm allows processing of the raw data (signal intensities at different concentrations of added ligand) directly by mathematical evaluation via non-linear regression. Thus, several titration curves can be recorded simultaneously and transformed into a set of characteristic parameters, among them the dissociation constant and the concentration of binding-active receptor, and they can be evaluated statistically. When combined with this algorithm, titration ELISAs gain the advantage of directly presenting the dissociation constant. Therefore, they may be used more efficiently in the future.

Accuracy and reliability of the Pfeffer Questionnaire for the Brazilian elderly population

PubMed Central

Dutra, Marina Carneiro; Ribeiro, Raynan dos Santos; Pinheiro, Sarah Brandão; de Melo, Gislane Ferreira; Carvalho, Gustavo de Azevedo

2015-01-01

The aging population calls for instruments to assess functional and cognitive impairment in the elderly, aiming to prevent conditions that affect functional abilities. Objective To verify the accuracy and reliability of the Pfeffer (FAQ) scale for the Brazilian elderly population and to evaluate the reliability and reproducibility of the translated version of the Pfeffer Questionnaire. Methods The Brazilian version of the FAQ was applied to 110 elderly divided into two groups. Both groups were assessed by two blinded investigators at baseline and again after 15 days. In order to verify the accuracy and reliability of the instrument, sensitivity and specificity measurements for the presence or absence of functional and cognitive decline were calculated for various cut-off points and the ROC curve. Intra and inter-examiner reliability were assessed using the Interclass Correlation Coefficient (ICC) and Bland-Altman plots. Results For the occurrence of cognitive decline, the ROC curve yielded an area under the curve of 0.909 (95%CI of 0.845 to 0.972), sensitivity of 75.68% (95%CI of 93.52% to 100%) and specificity of 97.26%. For the occurrence of functional decline, the ROC curve yielded an area under the curve of 0.851 (95%CI of 64.52% to 87.33%) and specificity of 80.36% (95%CI of 69.95% to 90.76%). The ICC was excellent, with all values exceeding 0.75. On the Bland-Altman plot, intra-examiner agreement was good, with p>0.05consistently close to 0. A systematic difference was found for inter-examiner agreement. Conclusion The Pfeffer Questionnaire is applicable in the Brazilian elderly population and showed reliability and reproducibility compared to the original test. PMID:29213959

Percentage entrainment of constituent loads in urban runoff, south Florida

USGS Publications Warehouse

Miller, R.A.

1985-01-01

Runoff quantity and quality data from four urban basins in south Florida were analyzed to determine the entrainment of total nitrogen, total phosphorus, total carbon, chemical oxygen demand, suspended solids, and total lead within the stormwater runoff. Land use of the homogeneously developed basins are residential (single family), highway, commercial, and apartment (multifamily). A computational procedure was used to calculate, for all storms that had water-quality data, the percentage of constituent load entrainment in specified depths of runoff. The plot of percentage of constituent load entrained as a function of runoff is termed the percentage-entrainment curve. Percentage-entrainment curves were developed for three different source areas of basin runoff: (1) the hydraulically effective impervious area, (2) the contributing area, and (3) the drainage area. With basin runoff expressed in inches over the contributing area, the depth of runoff required to remove 90 percent of the constituent load ranged from about 0.4 inch to about 1.4 inches; and to remove 80 percent, from about 0.3 to 0.9 inch. Analysis of variance, using depth of runoff from the contributing area as the response variable, showed that the factor 'basin' is statistically significant, but that the factor 'constituent' is not statistically significant in the forming of the percentage-entrainment curve. Evidently the sewerage design, whether elongated or concise in plan dictates the shape of the percentage-entrainment curve. The percentage-entrainment curves for all constituents were averaged for each basin and plotted against basin runoff for three source areas of runoff-the hydraulically effective impervious area, the contributing area, and the drainage area. The relative positions of the three curves are directly related to the relative sizes of the three source areas considered. One general percentage-entrainment curve based on runoff from the contributing area was formed by averaging across both constituents and basins. Its coordinates are: 0.25 inch of runoff for 50-percent entrainment, 0.65 inch of runoff for 80-percent entrainment, and 0.95 inch of runoff for 90-percent entrainment. The general percentage-entrainment curve based on runoff from the hydraulically effective impervious area has runoff values of 0.35, 0.95, 1.6 inches, respectively.

Relationships among environmental variables and distribution of tree species at high elevation in the Olympic Mountains

USGS Publications Warehouse

Woodward, Andrea

1998-01-01

Relationships among environmental variables and occurrence of tree species were investigated at Hurricane Ridge in Olympic National Park, Washington, USA. A transect consisting of three plots was established down one north-and one south-facing slope in stands representing the typical elevational sequence of tree species. Tree species included subalpine fir (Abies lasiocarpa), Douglas-fir (Pseudotsuga menziesii), mountain hemlock (Tsuga mertensiana), and Pacific silver fir (Abies amabilis). Air and soil temperature, precipitation, and soil moisture were measured during three growing seasons. Snowmelt patterns, soil carbon and moisture release curves were also determined. The plots represented a wide range in soil water potential, a major determinant of tree species distribution (range of minimum values = -1.1 to -8.0 MPa for Pacific silver fir and Douglas-fir plots, respectively). Precipitation intercepted at plots depended on topographic location, storm direction and storm type. Differences in soil moisture among plots was related to soil properties, while annual differences at each plot were most often related to early season precipitation. Changes in climate due to a doubling of atmospheric CO2 will likely shift tree species distributions within, but not among aspects. Change will be buffered by innate tolerance of adult trees and the inertia of soil properties.

Serum hepcidin-25 may replace the ferritin index in the Thomas plot in assessing iron status in anemic patients.

PubMed

Thomas, C; Kobold, U; Balan, S; Roeddiger, R; Thomas, L

2011-04-01

Biochemical markers of iron deficiency do not distinguish iron-deficient anemia (IDA) from the anemia of chronic disease (ACD) and the combined state of ACD/IDA. Serum hepcidin-25 might be a marker resolving this problem. We investigated the extent to which serum hepcidin-25 enables the differentiation of the states above in comparison with the ferritin index plot, the so-called Thomas plot [soluble transferrin receptor (sTfR)/log ferritin and the reticulocyte hemoglobin content (CHr)]. Serum hepcidin-25 was determined in 155 anemic patients who were classified as having latent iron deficiency (latent ID), IDA, ACD, or ACD/IDA using the ferritin index plot (Thomas plot). Hepcidin-25 was determined using an isotope-dilution micro-HPLC-tandem mass spectrometry method. The ability to discriminate among these states based on serum hepcidin-25 alone or in combination with the CHr was evaluated in a receiver operating characteristic curve analysis and a comparison with the recently established ferritin index plot. Serum hepcidin-25 correlated with ferritin and the ferritin index. Use of a hepcidin-25 cutoff level of ≤4 nmol/l allowed the differentiation of IDA from ACD and ACD/IDA. Furthermore, the discrimination of ACD/IDA from ACD required combination with CHr in a new plot (hepcidin-25 and the CHr). The hepcidin-25 plot and the ferritin index plot showed a good correspondence in the differentiation of iron states in patients with anemia. Patients with IDA can be differentiated from ACD and ACD/IDA but not ACD from ACD/IDA based on hepcidin-25 alone. The combination of hepcidin-25 with CHr in the hepcidin-25 plot was useful for the differentiation of the states above. © 2010 Blackwell Publishing Ltd.

Geologic map of the Fifteenmile Valley 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Miller, F.K.; Matti, J.C.

2001-01-01

Open-File Report OF 01-132 contains a digital geologic map database of the Fifteenmile Valley 7.5’ quadrangle, San Bernardino County, California that includes: 1. ARC/INFO (Environmental Systems Research Institute, http://www.esri.com) version 7.2.1 coverages of the various elements of the geologic map. 2. A PostScript file to plot the geologic map on a topographic base, and containing a Correlation of Map Units diagram, a Description of Map Units, an index map, and a regional structure map. 3. Portable Document Format (.pdf) files of: a. This Readme; includes in Appendix I, data contained in fif_met.txt b. The same graphic as plotted in 2 above. (Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat pagesize setting influences map scale.) The Correlation of Map Units (CMU) and Description of Map Units (DMU) is in the editorial format of USGS Miscellaneous Investigations Series (I-series) maps. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U. S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). If roads in some areas, especially forest roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS Fifteenmile Valley 7.5’ topographic quadrangle in conjunction with the geologic map.

Quadrantal multi-scale distribution entropy analysis of heartbeat interval series based on a modified Poincaré plot

NASA Astrophysics Data System (ADS)

Huo, Chengyu; Huang, Xiaolin; Zhuang, Jianjun; Hou, Fengzhen; Ni, Huangjing; Ning, Xinbao

2013-09-01

The Poincaré plot is one of the most important approaches in human cardiac rhythm analysis. However, further investigations are still needed to concentrate on techniques that can characterize the dispersion of the points displayed by a Poincaré plot. Based on a modified Poincaré plot, we provide a novel measurement named distribution entropy (DE) and propose a quadrantal multi-scale distribution entropy analysis (QMDE) for the quantitative descriptions of the scatter distribution patterns in various regions and temporal scales. We apply this method to the heartbeat interval series derived from healthy subjects and congestive heart failure (CHF) sufferers, respectively, and find that the discriminations between them are most significant in the first quadrant, which implies significant impacts on vagal regulation brought about by CHF. We also investigate the day-night differences of young healthy people, and it is shown that the results present a clearly circadian rhythm, especially in the first quadrant. In addition, the multi-scale analysis indicates that the results of healthy subjects and CHF sufferers fluctuate in different trends with variation of the scale factor. The same phenomenon also appears in circadian rhythm investigations of young healthy subjects, which implies that the cardiac dynamic system is affected differently in various temporal scales by physiological or pathological factors.

NCEP Air Quality Forecast(AQF) Verification. NOAA/NWS/NCEP/EMC

Science.gov Websites

average Select forecast four: Day 1 AOD skill for all thresholds Day 1 Time series for AOD GT 0 Day 2 AOD skill for all thresholds Day 2 Time series for AOD GT 0 Diurnal plots for AOD GT 0 Select statistic type

Direct recording of cardiac output- and venous return-curves in the dog heart-lung preparation for a graphical analysis of the effects of cardioactive drugs.

PubMed

Ishikawa, N; Taki, K; Hojo, Y; Hagino, Y; Shigei, T

1978-09-01

The dog heart-lung preparations were prepared. The "equilibrium point", which could be defined as the point at which the cardiac output (CO)-curve and the venous return (VR)-curve crossed, when the CO and VR were plotted against the right atrial pressure, was recorded directly by utilizing an X-Y recorder. The CO-curve was obtained, as a locus of the equilibrium point, by raising and lowering the level of blood in the venous reservoir (competence test). The meaning of the procedure was shown to increase or decrease the mean systemic pressure, and to cause the corresponding parallel shift in the VR-curve. The VR-curve was obtained by changing myocardial contractility. When heart failure was induced by pentobarbital or by chloroform, the equilibrium point shifted downwards to the right, depicting the VR-curve. During development of the failure, the slopes of CO-curves decreased gradually. Effects of cinobufagin and norepinephrine were also analyzed. Utilization of the X-Y recorder enabled us to settle the uniform experimental conditions more easily, and to follow the effects of drugs continuously on a diagram equating the CO- and VR-curves (Gyton's scheme).

Visual Data Analysis for Satellites

NASA Technical Reports Server (NTRS)

Lau, Yee; Bhate, Sachin; Fitzpatrick, Patrick

2008-01-01

The Visual Data Analysis Package is a collection of programs and scripts that facilitate visual analysis of data available from NASA and NOAA satellites, as well as dropsonde, buoy, and conventional in-situ observations. The package features utilities for data extraction, data quality control, statistical analysis, and data visualization. The Hierarchical Data Format (HDF) satellite data extraction routines from NASA's Jet Propulsion Laboratory were customized for specific spatial coverage and file input/output. Statistical analysis includes the calculation of the relative error, the absolute error, and the root mean square error. Other capabilities include curve fitting through the data points to fill in missing data points between satellite passes or where clouds obscure satellite data. For data visualization, the software provides customizable Generic Mapping Tool (GMT) scripts to generate difference maps, scatter plots, line plots, vector plots, histograms, timeseries, and color fill images.

Infiltration and solute transport experiments in unsaturated sand and gravel, Cape Cod, Massachusetts: Experimental design and overview of results

USGS Publications Warehouse

Rudolph, David L.; Kachanoski , R. Gary; Celia, Michael A.; LeBlanc, Denis R.; Stevens, Jonathon H.

1996-01-01

A series of infiltration and tracer experiments was conducted in unsaturated sand and gravel deposits on Cape Cod, Massachusetts. A network of 112 porous cup lysimeters and 168 time domain reflectometry (TDR) probes was deployed at depths from 0.25 to 2.0 m below ground surface along the centerline of a 2-m by 10-m test plot. The test plot was irrigated at rates ranging from 7.9 to 37.0 cm h−1 through a sprinkler system. Transient and steady state water content distributions were monitored with the TDR probes and spatial properties of water content distributions were determined from the TDR data. The spatial variance of the water content tended to increase as the average water content increased. In addition, estimated horizontal correlation length scales for water content were significantly smaller than those estimated by previous investigators for saturated hydraulic conductivity. Under steady state flow conditions at each irrigation rate, a sodium chloride solution was released as a tracer at ground surface and tracked with both the lysimeter and TDR networks. Transect-averaged breakthrough curves at each monitoring depth were constructed both from solute concentrations measured in the water samples and flux concentrations inferred from the TDR measurements. Transport properties, including apparent solute velocities, dispersion coefficients, and total mass balances, were determined independently from both sets of breakthrough curves. The dispersion coefficients tended to increase with depth, reaching a constant value with the lysimeter data and appearing to increase continually with the TDR data. The variations with depth of the solute transport parameters, along with observations of water and solute mass balance and spatial distributions of water content, provide evidence of significant three-dimensional flow during the irrigation experiments. The TDR methods are shown to efficiently provide dense spatial and temporal data sets for both flow and solute transport in unsaturated sediments with minimal sediment and flow field disturbance. Combined implementation of lysimeters and TDR probes can enhance data interpretation particularly when three-dimensional flow conditions are anticipated.

Method and apparatus for diagnosing breached fuel elements

DOEpatents

Gross, K.C.; Lambert, J.D.B.; Nomura, S.

1987-03-02

The invention provides an apparatus and method for diagnosing breached fuel elements in a nuclear reactor. A detection system measures the activity of isotopes from the cover gas in the reactor. A data acquisition and processing system monitors the detection system and corrects for the effects of the cover-gas clean up system on the measured activity and further calculates the derivative curve of the corrected activity as a function of time. A plotting system graphs the derivative curve, which represents the instantaneous release rate of fission gas from a breached fuel element. 8 figs.

Micromirror Array Control of a Phase-Locked Laser Diode Array

DTIC Science & Technology

1995-12-01

Micromirror Intensity-Voltage Curve . From the intensity plot, maxima (Ix) and minima (IMN) are noted. If IMAX and IMn are known, A4 can be calculated for...of the micromirror array used. Mirror 9 600 500 E 400- S300- C, -0200 lOO_ 0 0 5 10 15 20 25 30 Volts Figure 3b. Mirror Deflection Curve Corresponding...AFIT/GAP/ENP/95D-2 MICROMIRROR ARRAY CONTROL OF A PHASE-LOCKED LASER DIODE ARRAY THESIS Carl J. Christensen, Captain, USAF AFIT/GAP/ENP/95D-2

Geologic map of the Valjean Hills 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Calzia, J.P.; Troxel, Bennie W.; digital database by Raumann, Christian G.

2003-01-01

FGDC-compliant metadata for the ARC/INFO coverages. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3 above) or plotting the postscript file (2 above).

Curve Boxplot: Generalization of Boxplot for Ensembles of Curves.

PubMed

Mirzargar, Mahsa; Whitaker, Ross T; Kirby, Robert M

2014-12-01

In simulation science, computational scientists often study the behavior of their simulations by repeated solutions with variations in parameters and/or boundary values or initial conditions. Through such simulation ensembles, one can try to understand or quantify the variability or uncertainty in a solution as a function of the various inputs or model assumptions. In response to a growing interest in simulation ensembles, the visualization community has developed a suite of methods for allowing users to observe and understand the properties of these ensembles in an efficient and effective manner. An important aspect of visualizing simulations is the analysis of derived features, often represented as points, surfaces, or curves. In this paper, we present a novel, nonparametric method for summarizing ensembles of 2D and 3D curves. We propose an extension of a method from descriptive statistics, data depth, to curves. We also demonstrate a set of rendering and visualization strategies for showing rank statistics of an ensemble of curves, which is a generalization of traditional whisker plots or boxplots to multidimensional curves. Results are presented for applications in neuroimaging, hurricane forecasting and fluid dynamics.

Use of the AAVSO's International Variable Star Index (VSX) in an Undergraduate Astronomy Course Capstone Project (Abstract)

NASA Astrophysics Data System (ADS)

Larsen, K.

2017-12-01

(Abstract only) The author discusses a capstone project that utilizes the AAVSO's International Variable Star Index (VSX), ASAS light curves and phase plots, and the SIMBAD astronomical data repository in a laboratory-based undergraduate Stellar and Galactic Astronomy course.

On the Unity of Bradford's Law.

ERIC Educational Resources Information Center

Maia, M. J. F.; Maia, M. D.

1984-01-01

It is shown that there is no ambiguity in Bradford's theory of distribution. Starting with two basic postulates laid down by Bradford, a mathematical expression is derived such that its curve agrees with the experimentally plotted data for periodicals in fields of applied geophysics and lubrication. Five references are listed. (Author/EJS)

Quantifying the Uncertainty in Discharge Data Using Hydraulic Knowledge and Uncertain Gaugings

NASA Astrophysics Data System (ADS)

Renard, B.; Le Coz, J.; Bonnifait, L.; Branger, F.; Le Boursicaud, R.; Horner, I.; Mansanarez, V.; Lang, M.

2014-12-01

River discharge is a crucial variable for Hydrology: as the output variable of most hydrologic models, it is used for sensitivity analyses, model structure identification, parameter estimation, data assimilation, prediction, etc. A major difficulty stems from the fact that river discharge is not measured continuously. Instead, discharge time series used by hydrologists are usually based on simple stage-discharge relations (rating curves) calibrated using a set of direct stage-discharge measurements (gaugings). In this presentation, we present a Bayesian approach to build such hydrometric rating curves, to estimate the associated uncertainty and to propagate this uncertainty to discharge time series. The three main steps of this approach are described: (1) Hydraulic analysis: identification of the hydraulic controls that govern the stage-discharge relation, identification of the rating curve equation and specification of prior distributions for the rating curve parameters; (2) Rating curve estimation: Bayesian inference of the rating curve parameters, accounting for the individual uncertainties of available gaugings, which often differ according to the discharge measurement procedure and the flow conditions; (3) Uncertainty propagation: quantification of the uncertainty in discharge time series, accounting for both the rating curve uncertainties and the uncertainty of recorded stage values. In addition, we also discuss current research activities, including the treatment of non-univocal stage-discharge relationships (e.g. due to hydraulic hysteresis, vegetation growth, sudden change of the geometry of the section, etc.).

Launch Vehicle Propulsion Design with Multiple Selection Criteria

NASA Technical Reports Server (NTRS)

Shelton, Joey D.; Frederick, Robert A.; Wilhite, Alan W.

2005-01-01

The approach and techniques described herein define an optimization and evaluation approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system. The method uses Monte Carlo simulations, genetic algorithm solvers, a propulsion thermo-chemical code, power series regression curves for historical data, and statistical models in order to optimize a vehicle system. The system, including parameters for engine chamber pressure, area ratio, and oxidizer/fuel ratio, was modeled and optimized to determine the best design for seven separate design weight and cost cases by varying design and technology parameters. Significant model results show that a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Other key findings show the sensitivity of propulsion parameters, technology factors, and cost factors and how these parameters differ when cost and weight are optimized separately. Each of the three key propulsion parameters; chamber pressure, area ratio, and oxidizer/fuel ratio, are optimized in the seven design cases and results are plotted to show impacts to engine mass and overall vehicle mass.

Modeling and testing of reactive contaminant transport in drinking water pipes: chlorine response and implications for online contaminant detection.

PubMed

Jeffrey Yang, Y; Goodrich, James A; Clark, Robert M; Li, Sylvana Y

2008-03-01

A modified one-dimensional Danckwerts convection-dispersion-reaction (CDR) model is numerically simulated to explain the observed chlorine residual loss for a "slug" of reactive contaminants instantaneously introduced into a drinking water pipe of assumed no or negligible wall demand. In response to longitudinal dispersion, a contaminant propagates into the bulk phase where it reacts with disinfectants in the water. This process generates a U-shaped pattern of chlorine residual loss in a time-series concentration plot. Numerical modeling indicates that the residual loss curve geometry (i.e., slope, depth, and width) is a function of several variables such as axial Péclet number, reaction rate constants, molar fraction of the fast- and slow-reacting contaminants, and the quasi-steady-state chlorine decay inside the "slug" which serves as a boundary condition of the CDR model. Longitudinal dispersion becomes dominant for less reactive contaminants. Pilot-scale pipe flow experiments for a non-reactive sodium fluoride tracer and the fast-reacting aldicarb, a pesticide, were conducted under turbulent flow conditions (Re=9020 and 25,000). Both the experimental results and the CDR modeling are in agreement showing a close relationship among the aldicarb contaminant "slug", chlorine residual loss and its variations, and a concentration increase of chloride as the final reaction product. Based on these findings, the residual loss curve and its geometry are useful tools to identify the presence of a contaminant "slug" and infer its reactive properties in adaptive contaminant detections.

Optimal waist circumference cutoff value for defining the metabolic syndrome in postmenopausal Latin American women.

PubMed

Blümel, Juan E; Legorreta, Deborah; Chedraui, Peter; Ayala, Felix; Bencosme, Ascanio; Danckers, Luis; Lange, Diego; Espinoza, Maria T; Gomez, Gustavo; Grandia, Elena; Izaguirre, Humberto; Manriquez, Valentin; Martino, Mabel; Navarro, Daysi; Ojeda, Eliana; Onatra, William; Pozzo, Estela; Prada, Mariela; Royer, Monique; Saavedra, Javier M; Sayegh, Fabiana; Tserotas, Konstantinos; Vallejo, Maria S; Zuñiga, Cristina

2012-04-01

The aim of this study was to determine an optimal waist circumference (WC) cutoff value for defining the metabolic syndrome (METS) in postmenopausal Latin American women. A total of 3,965 postmenopausal women (age, 45-64 y), with self-reported good health, attending routine consultation at 12 gynecological centers in major Latin American cities were included in this cross-sectional study. Modified guidelines of the US National Cholesterol Education Program, Adult Treatment Panel III were used to assess METS risk factors. Receiver operator characteristic curve analysis was used to obtain an optimal WC cutoff value best predicting at least two other METS components. Optimal cutoff values were calculated by plotting the true-positive rate (sensitivity) against the false-positive rate (1 - specificity). In addition, total accuracy, distance to receiver operator characteristic curve, and the Youden Index were calculated. Of the participants, 51.6% (n = 2,047) were identified as having two or more nonadipose METS risk components (excluding a positive WC component). These women were older, had more years since menopause onset, used hormone therapy less frequently, and had higher body mass indices than women with fewer metabolic risk factors. The optimal WC cutoff value best predicting at least two other METS components was determined to be 88 cm, equal to that defined by the Adult Treatment Panel III. A WC cutoff value of 88 cm is optimal for defining METS in this postmenopausal Latin American series.

[Individual learning curve for radical robot-assisted prostatectomy based on the example of three professionals working in one clinic].

PubMed

Rasner, P I; Pushkar', D Iu; Kolontarev, K B; Kotenkov, D V

2014-01-01

The appearance of new surgical technique always requires evaluation of its effectiveness and ease of acquisition. A comparative study of the results of the first three series of successive robot-assisted radical prostatectomy (RARP) performed on at time by three surgeons, was conducted. The series consisted of 40 procedures, and were divided into 4 groups of 10 operations for the analysis. When comparing data, statistically significant improvement of intra- and postoperative performance in each series was revealed, with increase in the number of operations performed, and in each subsequent series compared with the preceding one. We recommend to perform the planned conversion at the first operation. In our study, previous laparoscopic experience did not provide any significant advantages in the acquisition of robot-assisted technology. To characterize the individual learning curve, we recommend the use of the number of operations that the surgeon looked in the life-surgery regimen and/or in which he participated as an assistant before his own surgical activity, as well as the indicator "technical defect". In addition to the term "individual learning curve", we propose to introduce the terms "surgeon's individual training phase", and "clinic's learning curve".

Isocratic and gradient impedance plot analysis and comparison of some recently introduced large size core-shell and fully porous particles.

PubMed

Vanderheyden, Yoachim; Cabooter, Deirdre; Desmet, Gert; Broeckhoven, Ken

2013-10-18

The intrinsic kinetic performance of three recently commercialized large size (≥4μm) core-shell particles packed in columns with different lengths has been measured and compared with that of standard fully porous particles of similar and smaller size (5 and 3.5μm, respectively). The kinetic performance is compared in both absolute (plot of t0 versus the plate count N or the peak capacity np for isocratic and gradient elution, respectively) and dimensionless units. The latter is realized by switching to so-called impedance plots, a format which has been previously introduced (as a plot of t0/N(2) or E0 versus Nopt/N) and has in the present study been extended from isocratic to gradient elution (where the impedance plot corresponds to a plot of t0/np(4) versus np,opt(2)/np(2)). Both the isocratic and gradient impedance plot yielded a very similar picture: the clustered impedance plot curves divide into two distinct groups, one for the core-shell particles (lowest values, i.e. best performance) and one for the fully porous particles (highest values), confirming the clear intrinsic kinetic advantage of core-shell particles. If used around their optimal flow rate, the core-shell particles displayed a minimal separation impedance that is about 40% lower than the fully porous particles. Even larger gains in separation speed can be achieved in the C-term regime. Copyright © 2013 Elsevier B.V. All rights reserved.

REVISITING EVIDENCE OF CHAOS IN X-RAY LIGHT CURVES: THE CASE OF GRS 1915+105

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

Mannattil, Manu; Gupta, Himanshu; Chakraborty, Sagar, E-mail: mmanu@iitk.ac.in, E-mail: hiugupta@iitk.ac.in, E-mail: sagarc@iitk.ac.in

2016-12-20

Nonlinear time series analysis has been widely used to search for signatures of low-dimensional chaos in light curves emanating from astrophysical bodies. A particularly popular example is the microquasar GRS 1915+105, whose irregular but systematic X-ray variability has been well studied using data acquired by the Rossi X-ray Timing Explorer . With a view to building simpler models of X-ray variability, attempts have been made to classify the light curves of GRS 1915+105 as chaotic or stochastic. Contrary to some of the earlier suggestions, after careful analysis, we find no evidence for chaos or determinism in any of the GRS 1915+105 classes. Themore » dearth of long and stationary data sets representing all the different variability classes of GRS 1915+105 makes it a poor candidate for analysis using nonlinear time series techniques. We conclude that either very exhaustive data analysis with sufficiently long and stationary light curves should be performed, keeping all the pitfalls of nonlinear time series analysis in mind, or alternative schemes of classifying the light curves should be adopted. The generic limitations of the techniques that we point out in the context of GRS 1915+105 affect all similar investigations of light curves from other astrophysical sources.« less

Relative equilibrium plot improves graphical analysis and allows bias correction of SUVR in quantitative [11C]PiB PET studies

PubMed Central

Zhou, Yun; Sojkova, Jitka; Resnick, Susan M.; Wong, Dean F.

2012-01-01

Both the standardized uptake value ratio (SUVR) and the Logan plot result in biased distribution volume ratios (DVR) in ligand-receptor dynamic PET studies. The objective of this study is to use a recently developed relative equilibrium-based graphical plot (RE plot) method to improve and simplify the two commonly used methods for quantification of [11C]PiB PET. Methods The overestimation of DVR in SUVR was analyzed theoretically using the Logan and the RE plots. A bias-corrected SUVR (bcSUVR) was derived from the RE plot. Seventy-eight [11C]PiB dynamic PET scans (66 from controls and 12 from mildly cognitively impaired participants (MCI) from the Baltimore Longitudinal Study of Aging (BLSA)) were acquired over 90 minutes. Regions of interest (ROIs) were defined on coregistered MRIs. Both the ROI and pixelwise time activity curves (TACs) were used to evaluate the estimates of DVR. DVRs obtained using the Logan plot applied to ROI TACs were used as a reference for comparison of DVR estimates. Results Results from the theoretical analysis were confirmed by human studies. ROI estimates from the RE plot and the bcSUVR were nearly identical to those from the Logan plot with ROI TACs. In contrast, ROI estimates from DVR images in frontal, temporal, parietal, cingulate regions, and the striatum were underestimated by the Logan plot (controls 4 – 12%; MCI 9 – 16%) and overestimated by the SUVR (controls 8 – 16%; MCI 16 – 24%). This bias was higher in the MCI group than in controls (p < 0.01) but was not present when data were analyzed using either the RE plot or the bcSUVR. Conclusion The RE plot improves pixel-wise quantification of [11C]PiB dynamic PET compared to the conventional Logan plot. The bcSUVR results in lower bias and higher consistency of DVR estimates compared to SUVR. The RE plot and the bcSUVR are practical quantitative approaches that improve the analysis of [11C]PiB studies. PMID:22414634

A new graphic plot analysis for determination of neuroreceptor binding in positron emission tomography studies.

PubMed

Ito, Hiroshi; Yokoi, Takashi; Ikoma, Yoko; Shidahara, Miho; Seki, Chie; Naganawa, Mika; Takahashi, Hidehiko; Takano, Harumasa; Kimura, Yuichi; Ichise, Masanori; Suhara, Tetsuya

2010-01-01

In positron emission tomography (PET) studies with radioligands for neuroreceptors, tracer kinetics have been described by the standard two-tissue compartment model that includes the compartments of nondisplaceable binding and specific binding to receptors. In the present study, we have developed a new graphic plot analysis to determine the total distribution volume (V(T)) and nondisplaceable distribution volume (V(ND)) independently, and therefore the binding potential (BP(ND)). In this plot, Y(t) is the ratio of brain tissue activity to time-integrated arterial input function, and X(t) is the ratio of time-integrated brain tissue activity to time-integrated arterial input function. The x-intercept of linear regression of the plots for early phase represents V(ND), and the x-intercept of linear regression of the plots for delayed phase after the equilibrium time represents V(T). BP(ND) can be calculated by BP(ND)=V(T)/V(ND)-1. Dynamic PET scanning with measurement of arterial input function was performed on six healthy men after intravenous rapid bolus injection of [(11)C]FLB457. The plot yielded a curve in regions with specific binding while it yielded a straight line through all plot data in regions with no specific binding. V(ND), V(T), and BP(ND) values calculated by the present method were in good agreement with those by conventional non-linear least-squares fitting procedure. This method can be used to distinguish graphically whether the radioligand binding includes specific binding or not.

Direct Behavior Rating: An Evaluation of Time-Series Interpretations as Consequential Validity

ERIC Educational Resources Information Center

Christ, Theodore J.; Nelson, Peter M.; Van Norman, Ethan R.; Chafouleas, Sandra M.; Riley-Tillman, T. Chris

2014-01-01

Direct Behavior Rating (DBR) is a repeatable and efficient method of behavior assessment that is used to document teacher perceptions of student behavior in the classroom. Time-series data can be graphically plotted and visually analyzed to evaluate patterns of behavior or intervention effects. This study evaluated the decision accuracy of novice…

A mathematical approach to beam matching

PubMed Central

Manikandan, A; Nandy, M; Gossman, M S; Sureka, C S; Ray, A; Sujatha, N

2013-01-01

Objective: This report provides the mathematical commissioning instructions for the evaluation of beam matching between two different linear accelerators. Methods: Test packages were first obtained including an open beam profile, a wedge beam profile and a depth–dose curve, each from a 10×10 cm2 beam. From these plots, a spatial error (SE) and a percentage dose error were introduced to form new plots. These three test package curves and the associated error curves were then differentiated in space with respect to dose for a first and second derivative to determine the slope and curvature of each data set. The derivatives, also known as bandwidths, were analysed to determine the level of acceptability for the beam matching test described in this study. Results: The open and wedged beam profiles and depth–dose curve in the build-up region were determined to match within 1% dose error and 1-mm SE at 71.4% and 70.8% for of all points, respectively. For the depth–dose analysis specifically, beam matching was achieved for 96.8% of all points at 1%/1 mm beyond the depth of maximum dose. Conclusion: To quantify the beam matching procedure in any clinic, the user needs to merely generate test packages from their reference linear accelerator. It then follows that if the bandwidths are smooth and continuous across the profile and depth, there is greater likelihood of beam matching. Differentiated spatial and percentage variation analysis is appropriate, ideal and accurate for this commissioning process. Advances in knowledge: We report a mathematically rigorous formulation for the qualitative evaluation of beam matching between linear accelerators. PMID:23995874

NLINEAR - NONLINEAR CURVE FITTING PROGRAM

NASA Technical Reports Server (NTRS)

Everhart, J. L.

1994-01-01

A common method for fitting data is a least-squares fit. In the least-squares method, a user-specified fitting function is utilized in such a way as to minimize the sum of the squares of distances between the data points and the fitting curve. The Nonlinear Curve Fitting Program, NLINEAR, is an interactive curve fitting routine based on a description of the quadratic expansion of the chi-squared statistic. NLINEAR utilizes a nonlinear optimization algorithm that calculates the best statistically weighted values of the parameters of the fitting function and the chi-square that is to be minimized. The inputs to the program are the mathematical form of the fitting function and the initial values of the parameters to be estimated. This approach provides the user with statistical information such as goodness of fit and estimated values of parameters that produce the highest degree of correlation between the experimental data and the mathematical model. In the mathematical formulation of the algorithm, the Taylor expansion of chi-square is first introduced, and justification for retaining only the first term are presented. From the expansion, a set of n simultaneous linear equations are derived, which are solved by matrix algebra. To achieve convergence, the algorithm requires meaningful initial estimates for the parameters of the fitting function. NLINEAR is written in Fortran 77 for execution on a CDC Cyber 750 under NOS 2.3. It has a central memory requirement of 5K 60 bit words. Optionally, graphical output of the fitting function can be plotted. Tektronix PLOT-10 routines are required for graphics. NLINEAR was developed in 1987.

VizieR Online Data Catalog: BVIc light curves of 57 Cepheids (Berdnikov+,

NASA Astrophysics Data System (ADS)

Berdnikov, L. N.; Kniazev, A. Yu.; Sefako, R.; Kravtsov, V. V.; Zhujko, S. V.

2014-04-01

In 2008-2013, we obtained 11333 CCD BV Ic frames for 57 Cepheids from the General Catalogue of Variable Stars. We performed our observations with the 76-cm telescope of the South AfricanAstronomicalObservatory (SAAO, South Africa) and the 40-cm telescope of the Cerro Armazones Astronomical Observatory of the Universidad Catolica del Norte (OCA, Chile) using the SBIG ST-10XME CCD camera. The tables of observations, the plots of light curves, and the current light elements are presented. Comparison of our light curves with those constructed from photoelectric observations shows that the differences between their mean magnitudes exceed 0.05mag in 20% of the cases. This suggests the necessity of performing CCD observations for all Cepheids. (2 data files).

Hydrodynamic measurements in Suisun Bay, California, 1992-93

USGS Publications Warehouse

Gartner, Jeffrey W.; Burau, Jon R.

1999-01-01

Sea level, velocity, temperature, and salinity (conductivity and temperature) data collected in Suisun Bay, California, from December 11, 1992, through May 31, 1993, by the U.S. Geological Survey are documented in this report. Sea-level data were collected at four locations and temperature and salinity data were collected at seven locations. Velocity data were collected at three locations using acoustic Doppler current profilers and at four other locations using point velocity meters. Sea-level and velocity data are presented in three forms (1) harmonic analysis results, (2) time-series plots (sea level, current speed, and current direction versus time), and (3) time-series plots of the low-pass filtered data. Temperature and salinity data are presented as plots of raw and low-pass filtered time series. The velocity and salinity data collected during this study document a period when the residual current patterns and salt field were significantly altered by large Delta outflow (three peaks in excess of 2,000 cubic meters per second). Residual current profiles were consistently seaward with magnitudes that fluctuated primarily in concert with Delta outflow and secondarily with the spring-neap tide cycle. The freshwater inputs advected salinity seaward of Suisun Bay for most of this study. Except for a 10-day period at the beginning of the study, dynamically significant salinities (>2) were seaward of Suisun Bay, which resulted in little or no gravitational circulation transport.

Driver for solar cell I-V characteristic plots

NASA Technical Reports Server (NTRS)

Turner, G. B. (Inventor)

1980-01-01

A bipolar voltage ramp generator which applies a linear voltage through a resistor to a solar cell for plotting its current versus voltage (I-V) characteristic between short circuit and open circuit conditions is disclosed. The generator has automatic stops at the end points. The resistor serves the multiple purpose of providing a current sensing resistor, setting the full-scale current value, and providing a load line with a slope approximately equal to one, such that it will pass through the origin and the approximate center of the I-V curve with about equal distance from that center to each of the end points.

Remote Sensing Time Series Product Tool

NASA Technical Reports Server (NTRS)

Predos, Don; Ryan, Robert E.; Ross, Kenton W.

2006-01-01

The TSPT (Time Series Product Tool) software was custom-designed for NASA to rapidly create and display single-band and band-combination time series, such as NDVI (Normalized Difference Vegetation Index) images, for wide-area crop surveillance and for other time-critical applications. The TSPT, developed in MATLAB, allows users to create and display various MODIS (Moderate Resolution Imaging Spectroradiometer) or simulated VIIRS (Visible/Infrared Imager Radiometer Suite) products as single images, as time series plots at a selected location, or as temporally processed image videos. Manually creating these types of products is extremely labor intensive; however, the TSPT development tool makes the process simplified and efficient. MODIS is ideal for monitoring large crop areas because of its wide swath (2330 km), its relatively small ground sample distance (250 m), and its high temporal revisit time (twice daily). Furthermore, because MODIS imagery is acquired daily, rapid changes in vegetative health can potentially be detected. The new TSPT technology provides users with the ability to temporally process high-revisit-rate satellite imagery, such as that acquired from MODIS and from its successor, the VIIRS. The TSPT features the important capability of fusing data from both MODIS instruments onboard the Terra and Aqua satellites, which drastically improves cloud statistics. With the TSPT, MODIS metadata is used to find and optionally remove bad and suspect data. Noise removal and temporal processing techniques allow users to create low-noise time series plots and image videos and to select settings and thresholds that tailor particular output products. The TSPT GUI (graphical user interface) provides an interactive environment for crafting what-if scenarios by enabling a user to repeat product generation using different settings and thresholds. The TSPT Application Programming Interface provides more fine-tuned control of product generation, allowing experienced programmers to bypass the GUI and to create more user-specific output products, such as comparison time plots or images. This type of time series analysis tool for remotely sensed imagery could be the basis of a large-area vegetation surveillance system. The TSPT has been used to generate NDVI time series over growing seasons in California and Argentina and for hurricane events, such as Hurricane Katrina.

Validity of the t-plot method to assess microporosity in hierarchical micro/mesoporous materials.

PubMed

Galarneau, Anne; Villemot, François; Rodriguez, Jeremy; Fajula, François; Coasne, Benoit

2014-11-11

The t-plot method is a well-known technique which allows determining the micro- and/or mesoporous volumes and the specific surface area of a sample by comparison with a reference adsorption isotherm of a nonporous material having the same surface chemistry. In this paper, the validity of the t-plot method is discussed in the case of hierarchical porous materials exhibiting both micro- and mesoporosities. Different hierarchical zeolites with MCM-41 type ordered mesoporosity are prepared using pseudomorphic transformation. For comparison, we also consider simple mechanical mixtures of microporous and mesoporous materials. We first show an intrinsic failure of the t-plot method; this method does not describe the fact that, for a given surface chemistry and pressure, the thickness of the film adsorbed in micropores or small mesopores (< 10σ, σ being the diameter of the adsorbate) increases with decreasing the pore size (curvature effect). We further show that such an effect, which arises from the fact that the surface area and, hence, the free energy of the curved gas/liquid interface decreases with increasing the film thickness, is captured using the simple thermodynamical model by Derjaguin. The effect of such a drawback on the ability of the t-plot method to estimate the micro- and mesoporous volumes of hierarchical samples is then discussed, and an abacus is given to correct the underestimated microporous volume by the t-plot method.

A statistical data analysis and plotting program for cloud microphysics experiments

NASA Technical Reports Server (NTRS)

Jordan, A. J.

1981-01-01

The analysis software developed for atmospheric cloud microphysics experiments conducted in the laboratory as well as aboard a KC-135 aircraft is described. A group of four programs was developed and implemented on a Hewlett Packard 1000 series F minicomputer running under HP's RTE-IVB operating system. The programs control and read data from a MEMODYNE Model 3765-8BV cassette recorder, format the data on the Hewlett Packard disk subsystem, and generate statistical data (mean, variance, standard deviation) and voltage and engineering unit plots on a user selected plotting device. The programs are written in HP FORTRAN IV and HP ASSEMBLY Language with the graphics software using the HP 1000 Graphics. The supported plotting devices are the HP 2647A graphics terminal, the HP 9872B four color pen plotter, and the HP 2608A matrix line printer.

Runoff potentiality of a watershed through SCS and functional data analysis technique.

PubMed

Adham, M I; Shirazi, S M; Othman, F; Rahman, S; Yusop, Z; Ismail, Z

2014-01-01

Runoff potentiality of a watershed was assessed based on identifying curve number (CN), soil conservation service (SCS), and functional data analysis (FDA) techniques. Daily discrete rainfall data were collected from weather stations in the study area and analyzed through lowess method for smoothing curve. As runoff data represents a periodic pattern in each watershed, Fourier series was introduced to fit the smooth curve of eight watersheds. Seven terms of Fourier series were introduced for the watersheds 5 and 8, while 8 terms of Fourier series were used for the rest of the watersheds for the best fit of data. Bootstrapping smooth curve analysis reveals that watersheds 1, 2, 3, 6, 7, and 8 are with monthly mean runoffs of 29, 24, 22, 23, 26, and 27 mm, respectively, and these watersheds would likely contribute to surface runoff in the study area. The purpose of this study was to transform runoff data into a smooth curve for representing the surface runoff pattern and mean runoff of each watershed through statistical method. This study provides information of runoff potentiality of each watershed and also provides input data for hydrological modeling.

Runoff Potentiality of a Watershed through SCS and Functional Data Analysis Technique

PubMed Central

Adham, M. I.; Shirazi, S. M.; Othman, F.; Rahman, S.; Yusop, Z.; Ismail, Z.

2014-01-01

Runoff potentiality of a watershed was assessed based on identifying curve number (CN), soil conservation service (SCS), and functional data analysis (FDA) techniques. Daily discrete rainfall data were collected from weather stations in the study area and analyzed through lowess method for smoothing curve. As runoff data represents a periodic pattern in each watershed, Fourier series was introduced to fit the smooth curve of eight watersheds. Seven terms of Fourier series were introduced for the watersheds 5 and 8, while 8 terms of Fourier series were used for the rest of the watersheds for the best fit of data. Bootstrapping smooth curve analysis reveals that watersheds 1, 2, 3, 6, 7, and 8 are with monthly mean runoffs of 29, 24, 22, 23, 26, and 27 mm, respectively, and these watersheds would likely contribute to surface runoff in the study area. The purpose of this study was to transform runoff data into a smooth curve for representing the surface runoff pattern and mean runoff of each watershed through statistical method. This study provides information of runoff potentiality of each watershed and also provides input data for hydrological modeling. PMID:25152911

U-series dating of impure carbonates: An isochron technique using total-sample dissolution

USGS Publications Warehouse

Bischoff, J.L.; Fitzpatrick, J.A.

1991-01-01

U-series dating is a well-established technique for age determination of Late Quaternary carbonates. Materials of sufficient purity for nominal dating, however, are not as common as materials with mechanically inseparable aluminosilicate detritus. Detritus contaminates the sample with extraneous Th. We propose that correction for contamination is best accomplished with the isochron technique using total sample dissolution (TSD). Experiments were conducted on artificial mixtures of natural detritus and carbonate and on an impure carbonate of known age. Results show that significant and unpredictable transfer of radionuclides occur from the detritus to the leachate in commonly used selective leaching procedures. The effects of correcting via leachate-residue pairs and isochron plots were assessed. Isochrons using TSD gave best results, followed by isochron plots of leachates only. ?? 1991.

Characterizing Decision-Analysis Performances of Risk Prediction Models Using ADAPT Curves.

PubMed

Lee, Wen-Chung; Wu, Yun-Chun

2016-01-01

The area under the receiver operating characteristic curve is a widely used index to characterize the performance of diagnostic tests and prediction models. However, the index does not explicitly acknowledge the utilities of risk predictions. Moreover, for most clinical settings, what counts is whether a prediction model can guide therapeutic decisions in a way that improves patient outcomes, rather than to simply update probabilities.Based on decision theory, the authors propose an alternative index, the "average deviation about the probability threshold" (ADAPT).An ADAPT curve (a plot of ADAPT value against the probability threshold) neatly characterizes the decision-analysis performances of a risk prediction model.Several prediction models can be compared for their ADAPT values at a chosen probability threshold, for a range of plausible threshold values, or for the whole ADAPT curves. This should greatly facilitate the selection of diagnostic tests and prediction models.

MM Herculis - An eclipsing binary of the RS CVn

NASA Technical Reports Server (NTRS)

Sowell, J. R.; Hall, D. S.; Henry, G. W.; Burke, E. W., Jr.; Milone, E. F.

1983-01-01

V, B and U differential photoelectric photometry has been obtained for the RS Canum Venaticorum-class eclipsing binary star MM Her, with the light outside the eclipse being Fourier-analyzed to study wave migration and amplitude. These, together with the mean light level of the system, have been monitored from 1976 through 1980. Observations within the eclipse have revealed eclipses to be partial, rather than total as previously thought. The geometric elements of the presently rectified light curve are forced on the pre-1980 light curves and found to be compatible. With these elements, and previously obtained double line radial velocity curves, new absolute dimensions of 1.18 solar masses and 1.58 solar radii are calculated for the hotter star and 1.27 solar masses and 2.83 solar radii for the cooler star. The plotting of color indices on the color-color curve indicates G2V and K2IV spectral types.

Atlas of the Light Curves and Phase Plane Portraits of Selected Long-Period Variables

NASA Astrophysics Data System (ADS)

Kudashkina, L. S.; Andronov, I. L.

2017-12-01

For a group of the Mira-type stars, semi-regular variables and some RV Tau - type stars the limit cycles were computed and plotted using the phase plane diagrams. As generalized coordinates x and x', we have used φ - the brightness of the star and its phase derivative. We have used mean phase light curves using observations of various authors from the databases of AAVSO, AFOEV, VSOLJ, ASAS and approximated using a trigonometric polynomial of statistically optimal degree. For a simple sine-like light curve, the limit cycle is a simple ellipse. In a case of more complicated light curve, in which harmonics are statistically significant, the limit cycle has deviations from the ellipse. In an addition to a classical analysis, we use the error estimates of the smoothing function and its derivative to constrain an "error corridor" in the phase plane.

Stability Investigation of a Blunted Cone and a Blunted Ogive with a Flared Cylinder Afterbody at Mach Numbers from 0.30 to 2.85

NASA Technical Reports Server (NTRS)

Coltrane, Lucille C.

1959-01-01

A cone with a blunt nose tip and a 10.7 deg cone half angle and an ogive with a blunt nose tip and a 20 deg flared cylinder afterbody have been tested in free flight over a Mach number range of 0.30 to 2.85 and a Reynolds number range of 1 x 10(exp 6) to 23 x 10(exp 6). Time histories, cross plots of force and moment coefficients, and plots of the longitudinal force,coefficient, rolling velocity, aerodynamic center, normal- force-curve slope, and dynamic stability are presented. With the center-of-gravity location at about 50 percent of the model length, the models were both statically and dynamically stable throughout the Mach number range. For the cone, the average aerodynamic center moved slightly forward with decreasing speeds and the normal-force-curve slope was fairly constant throughout the speed range. For the ogive, the average aerodynamic center remained practically constant and the normal-force-curve slope remained practically constant to a Mach number of approximately 1.6 where a rising trend is noted. Maximum drag coefficient for the cone, with reference to the base area, was approximately 0.6, and for the ogive, with reference to the area of the cylindrical portion, was approximately 2.1.

Dielectric relaxations on erythrocyte membrane as revealed by spectrin denaturation.

PubMed

Ivanov, I T; Paarvanova, B

2016-08-01

We studied the effect of spectrin denaturation at 49.5°C (TA) on the dielectric relaxations and related changes in the complex impedance, Z*, complex capacitance, C*, and dielectric loss curve of suspensions containing human erythrocytes, erythrocyte ghost membranes (EMs) and Triton-X-100 residues of EMs. The loss curve prior to, minus the loss curve after TA, resulted in a bell-shaped peak at 1.5MHz. The changes in the real and imaginary components of Z* and C* at TA, i.e., ΔZre, ΔZim, ΔCre and ΔCim, calculated in the same way, strongly varied with frequency. Between 1.0 and 12MHz the -ΔZim vs ΔZre, and ΔCim vs ΔCre plots depicted semicircles with critical frequencies, fcr, at 2.5MHz expressing recently reported relaxation of spectrin dipoles. Between 0.02 and 1.0MHz the -ΔZim vs ΔZre plot exhibited another relaxation whose fcr mirrored that of beta relaxation. This relaxation was absent on Triton-X-shells, while on erythrocytes and EMs it was inhibited by selective dissociation of either attachment sites between spectrin and bilayer. Considering above findings and inaccessibility of cytosole to outside field at such frequencies, the latter relaxation was assumed originating from a piezoelectric effect on the highly deformable spectrin filaments. Copyright © 2016 Elsevier B.V. All rights reserved.

Multipurpose Corrosion Inhibitors for Aerospace Materials in Naval Environments

DTIC Science & Technology

1987-06-04

Figure 1. The (da/dN i vs. AK plot is typica: of tr " curves obtained. The abbreviations MA. CTM and DNBM stand for moist air. dichromate - tellurate ...plastic deformation which occurs by the movement of dislocations to the surface (19) is the precursor of the cracking process in metals. Since

Monitoring larval populations of the Douglas-fir tussock moth and the western spruce budworm on permanent plots: sampling methods and statistical properties of data

Treesearch

A.R. Mason; H.G. Paul

1994-01-01

Procedures for monitoring larval populations of the Douglas-fir tussock moth and the western spruce budworm are recommended based on many years experience in sampling these species in eastern Oregon and Washington. It is shown that statistically reliable estimates of larval density can be made for a population by sampling host trees in a series of permanent plots in a...

Asymptotic scalings of developing curved pipe flow

NASA Astrophysics Data System (ADS)

Ault, Jesse; Chen, Kevin; Stone, Howard

2015-11-01

Asymptotic velocity and pressure scalings are identified for the developing curved pipe flow problem in the limit of small pipe curvature and high Reynolds numbers. The continuity and Navier-Stokes equations in toroidal coordinates are linearized about Dean's analytical curved pipe flow solution (Dean 1927). Applying appropriate scaling arguments to the perturbation pressure and velocity components and taking the limits of small curvature and large Reynolds number yields a set of governing equations and boundary conditions for the perturbations, independent of any Reynolds number and pipe curvature dependence. Direct numerical simulations are used to confirm these scaling arguments. Fully developed straight pipe flow is simulated entering a curved pipe section for a range of Reynolds numbers and pipe-to-curvature radius ratios. The maximum values of the axial and secondary velocity perturbation components along with the maximum value of the pressure perturbation are plotted along the curved pipe section. The results collapse when the scaling arguments are applied. The numerically solved decay of the velocity perturbation is also used to determine the entrance/development lengths for the curved pipe flows, which are shown to scale linearly with the Reynolds number.

Kinetics of Cathode Processes in Separation of Thorium from Molten Salts. Part I. Investigation of ThF$sub 4$ and ThF$sub 4$-CaF$sub 2$; KINETYKA PROCESU KATODOWEGO PRZY OSADZANIU TORU ZE STOPIONYCH SOLI. CZESC I. BADANIA ThF$sub 4$ I ThF$sub 4$-CaF$sub 2$

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

Mints, S.; Rafal'skii, V.

1961-09-01

The current-intensity curves of non-electrolyzed salts and the curves of time-intensity and current-intensity in electrolyzed salts were plotted for molten ThF/sub 4/ and ThF /sub 4/CaF/sub 2/. The intensity of salt disintegration was determined, and electric conductivity in electrolyte was observed. (trauth)

Thoracic Injury Risk Curves for Rib Deflections of the SID-IIs Build Level D.

PubMed

Irwin, Annette L; Crawford, Greg; Gorman, David; Wang, Sikui; Mertz, Harold J

2016-11-01

Injury risk curves for SID-IIs thorax and abdomen rib deflections proposed for future NCAP side impact evaluations were developed from tests conducted with the SID-IIs FRG. Since the floating rib guide is known to reduce the magnitude of the peak rib deflections, injury risk curves developed from SID-IIs FRG data are not appropriate for use with SID-IIs build level D. PMHS injury data from three series of sled tests and one series of whole-body drop tests are paired with thoracic rib deflections from equivalent tests with SID-IIs build level D. Where possible, the rib deflections of SID-IIs build level D were scaled to adjust for differences in impact velocity between the PMHS and SID-IIs tests. Injury risk curves developed by the Mertz-Weber modified median rank method are presented and compared to risk curves developed by other parametric and non-parametric methods.

Griffiths-like phase, critical behavior near the paramagnetic-ferromagnetic phase transition and magnetic entropy change of nanocrystalline La0.75Ca0.25MnO3

NASA Astrophysics Data System (ADS)

Phong, P. T.; Ngan, L. T. T.; Dang, N. V.; Nguyen, L. H.; Nam, P. H.; Thuy, D. M.; Tuan, N. D.; Bau, L. V.; Lee, I. J.

2018-03-01

In this work, we report the structural and magnetic properties of La0.75Ca0.25MnO3 nanoparticles synthesized by the sol-gel route. Rietvield refinement of X-ray powder diffraction confirms that our sample is single phase and crystallizes in orthorhombic system with Pnma space group. The facts that effective magnetic moment is large and the inverse susceptibility deviates from the Curie Weiss lawn indicate the presence of Griffiths-like cluster phase. The critical exponents have been estimated using different techniques such as modified Arrott plot, Kouvel-Fisher plot and critical isotherm technique. The critical exponents values of La0.75Ca0.25MnO3 are very close to those found out by the mean-field model, and this can be explained by the existence of a long-range interactions between spins in this system. These results were in good agreement with those obtained using the critical exponents of magnetic entropy change. The self-consistency and reliability of the critical exponent was verified by the Widom scaling law and the universal scaling hypothesis. Using the Harris criterion, we deduced that the disorder is relevant in our case. The maximum magnetic entropy change (ΔSM) calculated from the M-H measurements is 3.47 J/kg K under an external field change of 5 T. The ΔSM-T curves collapsed onto a single master curve regardless of the composition and the applied field, confirming the magnetic ordering is of second order nature. The obtained result was compared to ones calculated based on the Arrott plot and a good concordance is observed. Moreover, the spontaneous magnetization obtained from the entropy change is in excellent agreement with that deduced by classically extrapolation the Arrott curves. This result confirms the validity of the estimation of the spontaneous magnetization using the magnetic entropy change.

Visualizing the pressure and time burden of intracranial hypertension in adult and paediatric traumatic brain injury.

PubMed

Güiza, Fabian; Depreitere, Bart; Piper, Ian; Citerio, Giuseppe; Chambers, Iain; Jones, Patricia A; Lo, Tsz-Yan Milly; Enblad, Per; Nillson, Pelle; Feyen, Bart; Jorens, Philippe; Maas, Andrew; Schuhmann, Martin U; Donald, Rob; Moss, Laura; Van den Berghe, Greet; Meyfroidt, Geert

2015-06-01

To assess the impact of the duration and intensity of episodes of increased intracranial pressure on 6-month neurological outcome in adult and paediatric traumatic brain injury. Analysis of prospectively collected minute-by-minute intracranial pressure and mean arterial blood pressure data of 261 adult and 99 paediatric traumatic brain injury patients from multiple European centres. The relationship of episodes of elevated intracranial pressure (defined as a pressure above a certain threshold during a certain time) with 6-month Glasgow Outcome Scale was visualized in a colour-coded plot. The colour-coded plot illustrates the intuitive concept that episodes of higher intracranial pressure can only be tolerated for shorter durations: the curve that delineates the duration and intensity of those intracranial pressure episodes associated with worse outcome is an approximately exponential decay curve. In children, the curve resembles that of adults, but the delineation between episodes associated with worse outcome occurs at lower intracranial pressure thresholds. Intracranial pressures above 20 mmHg lasting longer than 37 min in adults, and longer than 8 min in children, are associated with worse outcomes. In a multivariate model, together with known baseline risk factors for outcome in severe traumatic brain injury, the cumulative intracranial pressure-time burden is independently associated with mortality. When cerebrovascular autoregulation, assessed with the low-frequency autoregulation index, is impaired, the ability to tolerate elevated intracranial pressures is reduced. When the cerebral perfusion pressure is below 50 mmHg, all intracranial pressure insults, regardless of duration, are associated with worse outcome. The intracranial pressure-time burden associated with worse outcome is visualised in a colour-coded plot. In children, secondary injury occurs at lower intracranial pressure thresholds as compared to adults. Impaired cerebrovascular autoregulation reduces the ability to tolerate intracranial pressure insults. Thus, 50 mmHg might be the lower acceptable threshold for cerebral perfusion pressure.

The Remote Detection of Incipient Catastrophic Failure in Large Landslides

NASA Astrophysics Data System (ADS)

Petley, D.; Bulmer, M. H.; Murphy, W.; Mantovani, F.

2001-12-01

Landslide movement is commonly associated with brittle failure and ductile deformation. Kilburn and Petley (2001) proposed that cracking in landslides occurs due to downslope stress acting on the deforming horizon. If the assumption that a given crack event breaks a fixed distance of unbroken rock or soil the rate of cracking becomes equivalent to the number of crack events per unit time. Where crack growth (not nucleation) is occurring, the inverse rate of displacement changes linearly with time. Failure can be assumed to be the time at which displacement rates become infinitely large. Thus, for a slope heading towards catastrophic failure due to the development of a failure plane, this relationship would be linear, with the point at which failure will occur being the time when the line intercepts the x-axis. Increasing rates of deformation associated with ductile processes of crack nucleation would yield a curve with a negative gradient asymptopic to the x-axis. This hypothesis is being examined. In the 1960 movement of the Vaiont slide, Italy, although the rate of movement was accelerating, the plot of 1/deformation against time shows that it was increasing towards a steady state deformation. This movement has been associated with a low accumulated strain ductile phase of movement. In the 1963 movement event, the trend is linear. This was associated with a brittle phase of movement. A plot of 1/deformation against time for movement of the debris flow portion of the Tessina landslide (1998) shows a curve with a negative gradient asymptopic to the x-axis. This indicates that the debris flow moved as a result of ductile deformation processes. Plots of movement data for the Black Ven landslide over 1999 and 2001 also show curves that correlate with known deformation and catastrophic phases. The model results suggest there is a definable deformation pattern that is diagnostic of landslides approaching catastrophic failure. This pattern can be differentiated from landslides that are undergoing ductile deformation and those that are suffering crack nucleation.

Computer Operations Study of Reservoir Operations for Six Mississippi River Headwaters Dams. Appendix A.

DTIC Science & Technology

1982-06-01

p*A C.._ _ __ _ _ A, d.tibutiou is unhimta 4 iit 84~ L0 TABLE OF CONTENTS APPENDIX SCOPE OF WORK B MERGE AND COST PROGRAM DOCUMENTATION C FATSCO... PROGRAM TO COMPUTE TIME SERIES FREQUENCY RELATIONSHIPS D HEC-DSS - TIME SERIES DATA FILE MANAGEMENT SYSTEM E PLAN 1 -TIM SERIES DATA PLOTS AND ANNUAL...University of Minnesota, utilized an early version of the Hydrologic Engineering * Center’s (HEC) EEC-5c Computer Program . EEC is a Corps of Engineers

Monitoring cotton root rot by synthetic Sentinel-2 NDVI time series using improved spatial and temporal data fusion.

PubMed

Wu, Mingquan; Yang, Chenghai; Song, Xiaoyu; Hoffmann, Wesley Clint; Huang, Wenjiang; Niu, Zheng; Wang, Changyao; Li, Wang; Yu, Bo

2018-01-31

To better understand the progression of cotton root rot within the season, time series monitoring is required. In this study, an improved spatial and temporal data fusion approach (ISTDFA) was employed to combine 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Different Vegetation Index (NDVI) and 10-m Sentinetl-2 NDVI data to generate a synthetic Sentinel-2 NDVI time series for monitoring this disease. Then, the phenology of healthy cotton and infected cotton was modeled using a logistic model. Finally, several phenology parameters, including the onset day of greenness minimum (OGM), growing season length (GLS), onset of greenness increase (OGI), max NDVI value, and integral area of the phenology curve, were calculated. The results showed that ISTDFA could be used to combine time series MODIS and Sentinel-2 NDVI data with a correlation coefficient of 0.893. The logistic model could describe the phenology curves with R-squared values from 0.791 to 0.969. Moreover, the phenology curve of infected cotton showed a significant difference from that of healthy cotton. The max NDVI value, OGM, GSL and the integral area of the phenology curve for infected cotton were reduced by 0.045, 30 days, 22 days, and 18.54%, respectively, compared with those for healthy cotton.

The re-incarnation, re-interpretation and re-demise of the transition probability model.

PubMed

Koch, A L

1999-05-28

There are two classes of models for the cell cycle that have both a deterministic and a stochastic part; they are the transition probability (TP) models and sloppy size control (SSC) models. The hallmark of the basic TP model are two graphs: the alpha and beta plots. The former is the semi-logarithmic plot of the percentage of cell divisions yet to occur, this results in a horizontal line segment at 100% corresponding to the deterministic phase and a straight line sloping tail corresponding to the stochastic part. The beta plot concerns the differences of the age-at-division of sisters (the beta curve) and gives a straight line parallel to the tail of the alpha curve. For the SC models the deterministic part is the time needed for the cell to accumulate a critical amount of some substance(s). The variable part differs in the various variants of the general model, but they do not give alpha and beta curves with linear tails as postulated by the TP model. This paper argues against TP and for an elaboration of SSC type of model. The main argument against TP is that it assumes that the probability of the transition from the stochastic phase is time invariant even though it is certain that the cells are growing and metabolizing throughout the cell cycle; a fact that should make the transition probability be variable. The SSC models presume that cell division is triggered by the cell's success in growing and not simply the result of elapsed time. The extended model proposed here to accommodate the predictions of the SSC to the straight tailed parts of the alpha and beta plots depends on the existence of a few percent of the cell in a growing culture that are not growing normally, these are growing much slower or are temporarily quiescent. The bulk of the cells, however, grow nearly exponentially. Evidence for a slow growing component comes from experimental analyses of population size distributions for a variety of cell types by the Collins-Richmond technique. These subpopulations existence is consistent with the new concept that there are a large class of rapidly reversible mutations occurring in many organisms and at many loci serving a large range of purposes to enable the cell to survive environmental challenges. These mutations yield special subpopulations of cells within a population. The reversible mutational changes, relevant to the elaboration of SSC models, produce slow-growing cells that are either very large or very small in size; these later revert to normal growth and division. The subpopulations, however, distort the population distribution in such a way as to fit better the exponential tails of the alpha and beta curves of the TP model.

feets: feATURE eXTRACTOR for tIME sERIES

NASA Astrophysics Data System (ADS)

Cabral, Juan; Sanchez, Bruno; Ramos, Felipe; Gurovich, Sebastián; Granitto, Pablo; VanderPlas, Jake

2018-06-01

feets characterizes and analyzes light-curves from astronomical photometric databases for modelling, classification, data cleaning, outlier detection and data analysis. It uses machine learning algorithms to determine the numerical descriptors that characterize and distinguish the different variability classes of light-curves; these range from basic statistical measures such as the mean or standard deviation to complex time-series characteristics such as the autocorrelation function. The library is not restricted to the astronomical field and could also be applied to any kind of time series. This project is a derivative work of FATS (ascl:1711.017).

In situ method for estimating cell survival in a solid tumor

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

Alfieri, A.A.; Hahn, E.W.

1978-09-01

The response of the murine Meth-A fibrosarcoma to single and fractionated doses of x-irradiation, actinomycin D chemotherapy, and/or concomitant local tumor hyperthermia was assayed with the use of an in situ method for estimating cell kill within a solid tumor. The cell survival assay was based on a standard curve plotting number of inoculated viable cells with and without radiation-inactivated homologous tumor cells versus the time required for i.m. tumors to grow to 1.0 cu cm. The time for post-treatment tumors to grow to 1.0 cu cm was cross-referenced to the standard curve, and the number of surviving cells contributingmore » to tumor regrowth was estimated. The resulting surviving fraction curves closely resemble those obtained with in vitro systems.« less

Using volcano plots and regularized-chi statistics in genetic association studies.

PubMed

Li, Wentian; Freudenberg, Jan; Suh, Young Ju; Yang, Yaning

2014-02-01

Labor intensive experiments are typically required to identify the causal disease variants from a list of disease associated variants in the genome. For designing such experiments, candidate variants are ranked by their strength of genetic association with the disease. However, the two commonly used measures of genetic association, the odds-ratio (OR) and p-value may rank variants in different order. To integrate these two measures into a single analysis, here we transfer the volcano plot methodology from gene expression analysis to genetic association studies. In its original setting, volcano plots are scatter plots of fold-change and t-test statistic (or -log of the p-value), with the latter being more sensitive to sample size. In genetic association studies, the OR and Pearson's chi-square statistic (or equivalently its square root, chi; or the standardized log(OR)) can be analogously used in a volcano plot, allowing for their visual inspection. Moreover, the geometric interpretation of these plots leads to an intuitive method for filtering results by a combination of both OR and chi-square statistic, which we term "regularized-chi". This method selects associated markers by a smooth curve in the volcano plot instead of the right-angled lines which corresponds to independent cutoffs for OR and chi-square statistic. The regularized-chi incorporates relatively more signals from variants with lower minor-allele-frequencies than chi-square test statistic. As rare variants tend to have stronger functional effects, regularized-chi is better suited to the task of prioritization of candidate genes. Copyright © 2013 Elsevier Ltd. All rights reserved.

A colorimetric sensor for the selective detection of fluoride ions.

PubMed

Wan, Chin-Feng; Chir, Jiun-Ly; Wu, An-Tai

2017-05-01

A colorimetric receptor L was prepared. Receptor L can selectively sense F - based on distinct color changes among a series of ions. It can selectively sense F - through an intramolecular hydrogen bond interaction. A Job plot indicated a 1:1 complexation stoichiometry between receptor L and F - . The association constant for L-F - in CH 3 CN was determined as 9.70 × 10 4  M -1 using a Stern-Volmer plot. Copyright © 2016 John Wiley & Sons, Ltd.

2015 Summer Series - Andy Weir - The Martian: How Science Drove the Plot

NASA Image and Video Library

2015-06-30

NASA's Journey to Mars sets a goal beyond anything humanity has ever reached. With this monumental vision, we outline the parameters needed for survival. We put ourselves into the spacesuit of a Martian explorer and design what they need. In his novel, The Martian, Andy Weir communicates a quest for survival-- a thought experiment in innovation and ingenuity. Andy Weir will describe how science drove the plot of The Martian, illuminating the connectivity between science fiction and science fact.

Studies of excited states of HeH by the multi-reference configuration-interaction method

NASA Astrophysics Data System (ADS)

Lee, Chun-Woo; Gim, Yeongrok

2013-11-01

The excited states of a HeH molecule for an n of up to 4 are studied using the multi-reference configuration-interaction method and Kaufmann's Rydberg basis functions. The advantages of using two different ways of locating Rydberg orbitals, either on the atomic nucleus or at the charge centre of molecules, are exploited by limiting their application to different ranges of R. Using this method, the difference between the experimental binding energies of the lower Rydberg states obtained by Ketterle and the ab initio results obtained by van Hemert and Peyerimhoff is reduced from a few hundreds of wave numbers to a few tens of wave numbers. A substantial improvement in the accuracy allows us to obtain quantum defect curves characterized by the correct behaviour. We obtain several Rydberg series that have more than one member, such as the ns series (n = 2, 3 and 4), npσ series (n = 3 and 4), npπ (n = 2, 3, 4) series and ndπ (n = 3, 4) series. These quantum defect curves are compared to the quantum defect curves obtained by the R-matrix or the multichannel quantum defect theory methods.

Neural network and wavelets in prediction of cosmic ray variability: The North Africa as study case

NASA Astrophysics Data System (ADS)

Zarrouk, Neïla; Bennaceur, Raouf

2010-04-01

Since the Earth is permanently bombarded with energetic cosmic rays particles, cosmic ray flux has been monitored by ground based neutron monitors for decades. In this work an attempt is made to investigate the decomposition and reconstructions provided by Morlet wavelet technique, using data series of cosmic rays variabilities, then to constitute from this wavelet analysis an input data base for the neural network system with which we can then predict decomposition coefficients and all related parameters for other points. Thus the latter are used for the recomposition step in which the plots and curves describing the relative cosmic rays intensities are obtained in any points on the earth in which we do not have any information about cosmic rays intensities. Although neural network associated with wavelets are not frequently used for cosmic rays time series, they seems very suitable and are a good choice to obtain these results. In fact we have succeeded to derive a very useful tool to obtain the decomposition coefficients, the main periods for each point on the Earth and on another hand we have now a kind of virtual NM for these locations like North Africa countries, Maroc, Algeria, Tunisia, Libya and Cairo. We have found the aspect of very known 11-years cycle: T1, we have also revealed the variation type of T2 and especially T3 cycles which seem to be induced by particular Earth's phenomena.

Geologic map and digital database of the Romoland 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Digital preparation by Bovard, Kelly R.; Morton, Gregory

2003-01-01

Portable Document Format (.pdf) files of: This Readme; includes in Appendix I, data contained in rom_met.txt The same graphic as plotted in 2 above. Test plots have not produced precise 1:24,000- scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formationname, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). This Readme file describes the digital data, such as types and general contents of files making up the database, and includes information on how to extract and plot the map and accompanying graphic file. Metadata information can be accessed at http://geo-nsdi.er.usgs.gov/metadata/open-file/03-102 and is included in Appendix I of this Readme.

Satellite altimetry based rating curves throughout the entire Amazon basin

NASA Astrophysics Data System (ADS)

Paris, A.; Calmant, S.; Paiva, R. C.; Collischonn, W.; Silva, J. S.; Bonnet, M.; Seyler, F.

2013-05-01

The Amazonian basin is the largest hydrological basin all over the world. In the recent past years, the basin has experienced an unusual succession of extreme draughts and floods, which origin is still a matter of debate. Yet, the amount of data available is poor, both over time and space scales, due to factor like basin's size, access difficulty and so on. One of the major locks is to get discharge series distributed over the entire basin. Satellite altimetry can be used to improve our knowledge of the hydrological stream flow conditions in the basin, through rating curves. Rating curves are mathematical relationships between stage and discharge at a given place. The common way to determine the parameters of the relationship is to compute the non-linear regression between the discharge and stage series. In this study, the discharge data was obtained by simulation through the entire basin using the MGB-IPH model with TRMM Merge input rainfall data and assimilation of gage data, run from 1998 to 2010. The stage dataset is made of ~800 altimetry series at ENVISAT and JASON-2 virtual stations. Altimetry series span between 2002 and 2010. In the present work we present the benefits of using stochastic methods instead of probabilistic ones to determine a dataset of rating curve parameters which are consistent throughout the entire Amazon basin. The rating curve parameters have been computed using a parameter optimization technique based on Markov Chain Monte Carlo sampler and Bayesian inference scheme. This technique provides an estimate of the best parameters for the rating curve, but also their posterior probability distribution, allowing the determination of a credibility interval for the rating curve. Also is included in the rating curve determination the error over discharges estimates from the MGB-IPH model. These MGB-IPH errors come from either errors in the discharge derived from the gage readings or errors in the satellite rainfall estimates. The present experiment shows that the stochastic approach is more efficient than the determinist one. By using for the parameters prior credible intervals defined by the user, this method provides an estimate of best rating curve estimate without any unlikely parameter, and all sites achieved convergence before reaching the maximum number of model evaluations. Results were assessed trough the Nash Sutcliffe efficiency coefficient, applied both to discharge and logarithm of discharges. Most of the virtual stations had good or very good results, showing values of Ens going from 0.7 to 0.98. However, worse results were found at a few virtual stations, unveiling the necessity of investigating possibilities of segmentation of the rating curve, depending on the stage or the rising or recession limb, but also possible errors in the altimetry series.

Statistical analysis of radioimmunoassay. In comparison with bioassay (in Japanese)

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

Nakano, R.

1973-01-01

Using the data of RIA (radioimmunoassay), statistical procedures for dealing with two problems of the linearization of dose response curve and calculation of relative potency were described. There were three methods for linearization of dose response curve of RIA. In each method, the following parameters were shown on the horizontal and vertical axis: dose x, (B/T)/sup -1/; c/x + c, B/T (C: dose which makes B/T 50%); log x, logit B/T. Among them, the last method seems to be most practical. The statistical procedures for bioassay were employed for calculating the relative potency of unknown samples compared to the standardmore » samples from dose response curves of standand and unknown samples using regression coefficient. It is desirable that relative potency is calculated by plotting more than 5 points in the standard curve and plotting more than 2 points in unknow samples. For examining the statistical limit of precision of measuremert, LH activity of gonadotropin in urine was measured and relative potency, precision coefficient and the upper and lower limits of relative potency at 95% confidence limit were calculated. On the other hand, bioassay (by the ovarian ascorbic acid reduction method and anteriol lobe of prostate weighing method) was done in the same samples, and the precision was compared with that of RIA. In these examinations, the upper and lower limits of the relative potency at 95% confidence limit were near each other, while in bioassay, a considerable difference was observed between the upper and lower limits. The necessity of standardization and systematization of the statistical procedures for increasing the precision of RIA was pointed out. (JA)« less

Assessing the performance of handheld glucose testing for critical care.

PubMed

Kost, Gerald J; Tran, Nam K; Louie, Richard F; Gentile, Nicole L; Abad, Victor J

2008-12-01

We assessed the performance of a point-of-care (POC) glucose meter system (GMS) with multitasking test strip by using the locally-smoothed (LS) median absolute difference (MAD) curve method in conjunction with a modified Bland-Altman difference plot and superimposed International Organization for Standardization (ISO) 15197 tolerance bands. We analyzed performance for tight glycemic control (TGC). A modified glucose oxidase enzyme with a multilayer-gold, multielectrode, four-well test strip (StatStriptrade mark, NOVA Biomedical, Waltham, MA) was used. There was no test strip calibration code. Pragmatic comparison was done of GMS results versus paired plasma glucose measurements from chemistry analyzers in clinical laboratories. Venous samples (n = 1,703) were analyzed at 35 hospitals that used 20 types of chemistry analyzers. Erroneous results were identified using the Bland-Altman plot and ISO 15197 criteria. Discrepant values were analyzed for the TGC interval of 80-110 mg/dL. The GMS met ISO 15197 guidelines; 98.6% (410 of 416) of observations were within tolerance for glucose <75 mg/dL, and for > or =75 mg/dL, 100% were within tolerance. Paired differences (handheld minus reference) averaged -2.2 (SD 9.8) mg/dL; the median was -1 (range, -96 to 45) mg/dL. LS MAD curve analysis revealed satisfactory performance below 186 mg/dL; above 186 mg/dL, the recommended error tolerance limit (5 mg/dL) was not met. No discrepant values appeared. All points fell in Clarke Error Grid zone A. Linear regression showed y = 1.018x - 0.716 mg/dL, and r2 = 0.995. LS MAD curves draw on human ability to discriminate performance visually. LS MAD curve and ISO 15197 performance were acceptable for TGC. POC and reference glucose calibration should be harmonized and standardized.

Simultaneous development of laparoscopy and robotics provides acceptable perioperative outcomes and shows robotics to have a faster learning curve and to be overall faster in rectal cancer surgery: analysis of novice MIS surgeon learning curves.

PubMed

Melich, George; Hong, Young Ki; Kim, Jieun; Hur, Hyuk; Baik, Seung Hyuk; Kim, Nam Kyu; Sender Liberman, A; Min, Byung Soh

2015-03-01

Laparoscopy offers some evidence of benefit compared to open rectal surgery. Robotic rectal surgery is evolving into an accepted approach. The objective was to analyze and compare laparoscopic and robotic rectal surgery learning curves with respect to operative times and perioperative outcomes for a novice minimally invasive colorectal surgeon. One hundred and six laparoscopic and 92 robotic LAR rectal surgery cases were analyzed. All surgeries were performed by a surgeon who was primarily trained in open rectal surgery. Patient characteristics and perioperative outcomes were analyzed. Operative time and CUSUM plots were used for evaluating the learning curve for laparoscopic versus robotic LAR. Laparoscopic versus robotic LAR outcomes feature initial group operative times of 308 (291-325) min versus 397 (373-420) min and last group times of 220 (212-229) min versus 204 (196-211) min-reversed in favor of robotics; major complications of 4.7 versus 6.5 % (NS), resection margin involvement of 2.8 versus 4.4 % (NS), conversion rate of 3.8 versus 1.1 (NS), lymph node harvest of 16.3 versus 17.2 (NS), and estimated blood loss of 231 versus 201 cc (NS). Due to faster learning curves for extracorporeal phase and total mesorectal excision phase, the robotic surgery was observed to be faster than laparoscopic surgery after the initial 41 cases. CUSUM plots demonstrate acceptable perioperative surgical outcomes from the beginning of the study. Initial robotic operative times improved with practice rapidly and eventually became faster than those for laparoscopy. Developing both laparoscopic and robotic skills simultaneously can provide acceptable perioperative outcomes in rectal surgery. It might be suggested that in the current milieu of clashing interests between evolving technology and economic constrains, there might be advantages in embracing both approaches.

The critical period of weed control in soybean (Glycine max (L.) Merr.) in north of Iran conditions.

PubMed

Keramati, Sara; Pirdashti, Hemmatollah; Esmaili, Mohammad Ali; Abbasian, Arastoo; Habibi, Marjaneh

2008-02-01

A field study was conducted in 2006 at Sari Agricultural and Natural Resources University, in order to determine the best time for weed control in soybean promising line, 033. Experiment was arranged in randomized complete block design with 4 replications and two series of treatments. In the first series, weeds were kept in place until crop reached V2 (second trifoliolate), V4 (fourth trifoliolate), V6 (sixth trifoliolate), R1 (beginning bloom, first flower), R3 (beginning pod), R5 (beginning seed) and were then removed and the crop kept weed-free for the rest of the season. In the second series, crops were kept weed-free until the above growth stages after which weeds were allowed to grow in the plots for the rest of the season. Whole season weedy and weed-free plots were included in the experiment for yield comparison. The results showed that among studied traits, grain yield, pod numbers per plant and weed biomass were affected significantly by control and interference treatments. The highest number of pods per plant was obtained from plots which kept weed-free for whole season control. Results showed that weed control should be carried out between V2 (26 day after planting) to R1 (63 day after planting) stages of soybean to provide maximum grain yield. Thus, it is possible to optimize the timing of weed control, which can serve to reduce the costs and side effects of intensive chemical weed control.

Low-cycle fatigue testing methods

NASA Technical Reports Server (NTRS)

Lieurade, H. P.

1978-01-01

The good design of highly stressed mechanical components requires accurate knowledge of the service behavior of materials. The main methods for solving the problems of designers are: determination of the mechanical properties of the material after cyclic stabilization; plotting of resistance to plastic deformation curves; effect of temperature on the life on low cycle fatigue; and simulation of notched parts behavior.

Tested Demonstrations: Buffer Capacity of Various Acetic Acid-Sodium Acetate Systems: A Lecture Experiment.

ERIC Educational Resources Information Center

Donahue, Craig J.; Panek, Mary G.

1985-01-01

Background information and procedures are provided for a lecture experiment which uses indicators to illustrate the concept of differing buffer capacities by titrating acetic acid/sodium acetate buffers with 1.0 molar hydrochloric acid and 1.0 molar sodium hydroxide. A table with data used to plot the titration curve is included. (JN)

Effect of carbide precipitation on the corrosion behavior of Inconel alloy 690

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

Sarver, J.M.; Crum, J.R.; Mankins, W.L.

1987-01-01

Intergranular carbide precipitation reactions have been shown to affect the stress corrosion cracking (SCC) resistance of nickel-chromium-iron alloys in environments relative to nuclear steam generators. Carbon solubility curves, time-temperature-sensitization plots and other carbide precipitation data are presented for alloy 690 as an aid in developing heat treatments for improved SCC resistance.

Electrostatic Discharge Properties of Irradiated Nanocomposites

DTIC Science & Technology

2009-03-01

47 24. Example Plot of Mean Current vs . Voltage Difference Curves ..................................48 25...across dielectric surfaces and prevent ESD arcing to very high voltage differentials (Figure 2) [7]. All of these drastic alterations in material...structure currents (3) Area thickness and dielectric strength of the material (4) Total charge involved in the event (5) Breakdown voltage (6) Current

Using Evolved Fuzzy Neural Networks for Injury Detection from Isokinetic Curves

NASA Astrophysics Data System (ADS)

Couchet, Jorge; Font, José María; Manrique, Daniel

In this paper we propose an evolutionary fuzzy neural networks system for extracting knowledge from a set of time series containing medical information. The series represent isokinetic curves obtained from a group of patients exercising the knee joint on an isokinetic dynamometer. The system has two parts: i) it analyses the time series input in order generate a simplified model of an isokinetic curve; ii) it applies a grammar-guided genetic program to obtain a knowledge base represented by a fuzzy neural network. Once the knowledge base has been generated, the system is able to perform knee injuries detection. The results suggest that evolved fuzzy neural networks perform better than non-evolutionary approaches and have a high accuracy rate during both the training and testing phases. Additionally, they are robust, as the system is able to self-adapt to changes in the problem without human intervention.

Estimating site index of ponderosa pine in Northern California...standard curves, soil series, stem analysis

Treesearch

Robert F. Powers

1972-01-01

Four sets of standard site index curves based on statewide or regionwide averages were compared with data on natural growth from nine young stands of ponderosa pine in northern California. The curves tested were by Meyer; Dunning; Dunning and Reineke; and Arvanitis, Lindquist, and Palley. The effects of soils on height growth were also studied. Among the curves tested...

Radar-derived asteroid shapes point to a 'zone of stability' for topography slopes and surface erosion rates

NASA Astrophysics Data System (ADS)

Richardson, J.; Graves, K.; Bowling, T.

2014-07-01

Previous studies of the combined effects of asteroid shape, spin, and self-gravity have focused primarily upon the failure limits for bodies with a variety of standard shapes, friction, and cohesion values [1,2,3]. In this study, we look in the opposite direction and utilize 22 asteroid shape-models derived from radar inversion [4] and 7 small body shape-models derived from spacecraft observations [5] to investigate the region in shape/spin space [1,2] wherein self-gravity and rotation combine to produce a stable minimum state with respect to surface potential differences, dynamic topography, slope magnitudes, and erosion rates. This erosional minimum state is self-correcting, such that changes in the body's rotation rate, either up or down, will increase slope magnitudes across the body, thereby driving up erosion rates non-linearly until the body has once again reached a stable, minimized surface state [5]. We investigated this phenomenon in a systematic fashion using a series of synthesized, increasingly prolate spheroid shape models. Adjusting the rotation rate of each synthetic shape to minimize surface potential differences, dynamic topography, and slope magnitudes results in the magenta curve of the figure (right side), defining the zone of maximum surface stability (MSS). This MSS zone is invariant both with respect to body size (gravitational potential and rotational potential scale together with radius), and density when the scaled-spin of [2] is used. Within our sample of observationally derived small-body shape models, slow rotators (Group A: blue points), that are not in the maximum surface stability (MSS) zone and where gravity dominates the slopes, will generally experience moderate erosion rates (left plot) and will tend to move up and to the right in shape/spin space as the body evolves (right plot). Fast rotators (Group C: red points), that are not in the MSS zone and where spin dominates the slopes, will generally experience high erosion rates (left plot) and will tend to move down and to the left in shape/spin space as the body evolves (right plot), barring other influences such as YORP spin-up [6]. Moderate rotators (Group B: green points) have slopes that are influenced equally by gravity and spin, lie in or near the self-correcting MSS zone (right plot), and will generally experience the lowest erosion rates (left plot). These objects comprise 12 (43%) of the 28 bodies studied, perhaps indicating some prevalence for the MSS zone. On the other hand, a sample of 1300 asteroid shape and spin parameters (small grey points), derived from asteroid lightcurve data [7], do not show this same degree of correlation, perhaps indicating the relative weakness of erosion-driven shape modification as compared to other influences. We will continue to investigate this phenomenon as the number of detailed shape models from ground-based radar and other observations continues to increase.

Phase relations in the system NaCl-KCl-H2O: IV. Differential thermal analysis of the sylvite liquidus in the KCl-H2O binary, the liquidus in the NaCl-KCl-H2O ternary, and the solidus in the NaCl-KCl binary to 2 kb pressure, and a summary of experimental data for thermodynamic-PTX analysis of solid-liquid equilibria at elevated P-T conditions

USGS Publications Warehouse

Chou, I.-Ming; Sterner, S.M.; Pitzer, Kenneth S.

1992-01-01

The sylvite liquidus in the binary system KCl-H2O and the liquidus in the ternary system NaCl-KCl-H2O were determined by using isobaric differential thermal analysis (DTA) cooling scans at pressures up to 2 kbars. Sylvite solubilities along the three-phase curve in the binary system KCl-H2O were obtained by the intersection of sylvite-liquidus isopleths with the three-phase curve in a P-T plot. These solubility data can be represented by the equation Wt.% KCl (??0.2) = 12.19 + 0.1557T - 5.4071 ?? 10-5 T2, where 400 ??? T ??? 770??C. These data are consistent with previous experimental observations. The solidus in the binary system NaCl-KCl was determined by using isobaric DTA heating scans at pressures up to 2 kbars. Using these liquidus and solidus data and other published information, a thermodynamic-PTX analysis of solid-liquid equilibria at high pressures and temperatures for the ternary system has been performed and is presented in an accompanying paper (Part V of this series). However, all experimental liquidus, solidus, and solvus data used in this analysis are summarized in this report (Part IV) and they are compared with the calculated values based on the analysis. ?? 1992.

Novel Flood Detection and Analysis Method Using Recurrence Property

NASA Astrophysics Data System (ADS)

Wendi, Dadiyorto; Merz, Bruno; Marwan, Norbert

2016-04-01

Temporal changes in flood hazard are known to be difficult to detect and attribute due to multiple drivers that include processes that are non-stationary and highly variable. These drivers, such as human-induced climate change, natural climate variability, implementation of flood defence, river training, or land use change, could impact variably on space-time scales and influence or mask each other. Flood time series may show complex behavior that vary at a range of time scales and may cluster in time. This study focuses on the application of recurrence based data analysis techniques (recurrence plot) for understanding and quantifying spatio-temporal changes in flood hazard in Germany. The recurrence plot is known as an effective tool to visualize the dynamics of phase space trajectories i.e. constructed from a time series by using an embedding dimension and a time delay, and it is known to be effective in analyzing non-stationary and non-linear time series. The emphasis will be on the identification of characteristic recurrence properties that could associate typical dynamic behavior to certain flood situations.

Geologic map of the Sunnymead 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Matti, Jonathan C.

2001-01-01

a. This Readme; includes in Appendix I, data contained in sun_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Visual evaluation of kinetic characteristics of PET probe for neuroreceptors using a two-phase graphic plot analysis.

PubMed

Ito, Hiroshi; Ikoma, Yoko; Seki, Chie; Kimura, Yasuyuki; Kawaguchi, Hiroshi; Takuwa, Hiroyuki; Ichise, Masanori; Suhara, Tetsuya; Kanno, Iwao

2017-05-01

Objectives In PET studies for neuroreceptors, tracer kinetics are described by the two-tissue compartment model (2-TCM), and binding parameters, including the total distribution volume (V T ), non-displaceable distribution volume (V ND ), and binding potential (BP ND ), can be determined from model parameters estimated by kinetic analysis. The stability of binding parameter estimates depends on the kinetic characteristics of radioligands. To describe these kinetic characteristics, we previously developed a two-phase graphic plot analysis in which V ND and V T can be estimated from the x-intercept of regression lines for early and delayed phases, respectively. In this study, we applied this graphic plot analysis to visual evaluation of the kinetic characteristics of radioligands for neuroreceptors, and investigated a relationship between the shape of these graphic plots and the stability of binding parameters estimated by the kinetic analysis with 2-TCM in simulated brain tissue time-activity curves (TACs) with various binding parameters. Methods 90-min TACs were generated with the arterial input function and assumed kinetic parameters according to 2-TCM. Graphic plot analysis was applied to these simulated TACs, and the curvature of the plot for each TAC was evaluated visually. TACs with several noise levels were also generated with various kinetic parameters, and the bias and variation of binding parameters estimated by kinetic analysis were calculated in each TAC. These bias and variation were compared with the shape of graphic plots. Results The graphic plots showed larger curvature for TACs with higher specific binding and slower dissociation of specific binding. The quartile deviations of V ND and BP ND determined by kinetic analysis were smaller for radioligands with slow dissociation. Conclusions The larger curvature of graphic plots for radioligands with slow dissociation might indicate a stable determination of V ND and BP ND by kinetic analysis. For investigation of the kinetics of radioligands, such kinetic characteristics should be considered.

Using pulse field gradient NMR diffusion measurements to define molecular size distributions in glycan preparations.

PubMed

Miller, Michelle C; Klyosov, Anatole; Platt, David; Mayo, Kevin H

2009-07-06

Glycans comprise perhaps the largest biomass in nature, and more and more glycans are used in a number of applications, including those as pharmaceutical agents in the clinic. However, defining glycan molecular weight distributions during and after their preparation is not always straightforward. Here, we use pulse field gradient (PFG) (1)H NMR self-diffusion measurements to assess molecular weight distributions in various glycan preparations. Initially, we derived diffusion coefficients, D, on a series of dextrans with reported weight-average molecular weights from about 5 kDa to 150 kDa. For each dextran sample, we analyzed 15 diffusion decay curves, one from each of the 15 major (1)H resonance envelopes, to provide diffusion coefficients. By measuring D as a function of dextran concentration, we determined D at infinite dilution, D(inf), which allowed estimation of the hydrodynamic radius, R(h), using the Stokes-Einstein relationship. A plot of log D(inf) versus log R(h) was linear and provided a standard calibration curve from which R(h) is estimated for other glycans. We then applied this methodology to investigate two other glycans, an alpha-(1-->2)-L-rhamnosyl-alpha-(1-->4)-D-galacturonosyl with quasi-randomly distributed, mostly terminal beta(1-->4)-linked galactose side-chains (GRG) and an alpha(1-->6)-D-galacto-beta(1-->4)-D-mannan (Davanat), which is presently being tested against cancer in the clinic. Using the dextran-derived calibration curve, we find that average R(h) values for GRG and Davanat are 76+/-6 x 10(-10) m and 56+/-3 x 10(-10) m, with GRG being more polydispersed than Davanat. Results from this study will be useful to investigators requiring knowledge of polysaccharide dispersity, needing to study polysaccharides under various solution conditions, or wanting to follow degradation of polysaccharides during production.

Non-parametric and least squares Langley plot methods

NASA Astrophysics Data System (ADS)

Kiedron, P. W.; Michalsky, J. J.

2016-01-01

Langley plots are used to calibrate sun radiometers primarily for the measurement of the aerosol component of the atmosphere that attenuates (scatters and absorbs) incoming direct solar radiation. In principle, the calibration of a sun radiometer is a straightforward application of the Bouguer-Lambert-Beer law V = V0e-τ ṡ m, where a plot of ln(V) voltage vs. m air mass yields a straight line with intercept ln(V0). This ln(V0) subsequently can be used to solve for τ for any measurement of V and calculation of m. This calibration works well on some high mountain sites, but the application of the Langley plot calibration technique is more complicated at other, more interesting, locales. This paper is concerned with ferreting out calibrations at difficult sites and examining and comparing a number of conventional and non-conventional methods for obtaining successful Langley plots. The 11 techniques discussed indicate that both least squares and various non-parametric techniques produce satisfactory calibrations with no significant differences among them when the time series of ln(V0)'s are smoothed and interpolated with median and mean moving window filters.

Van Allen Probes Science Gateway and Space Weather Data Processing

NASA Astrophysics Data System (ADS)

Romeo, G.; Barnes, R. J.; Weiss, M.; Fox, N. J.; Mauk, B.; Potter, M.; Kessel, R.

2014-12-01

The Van Allen Probes Science Gateway acts as a centralized interface to the instrument Science Operation Centers (SOCs), provides mission planning tools, and hosts a number of science related activities such as the mission bibliography. Most importantly, the Gateway acts as the primary site for processing and delivering the VAP Space Weather data to users. Over the past year, the web-site has been completely redesigned with the focus on easier navigation and improvements of the existing tools such as the orbit plotter, position calculator and magnetic footprint tool. In addition, a new data plotting facility has been added. Based on HTML5, which allows users to interactively plot Van Allen Probes summary and space weather data. The user can tailor the tool to display exactly the plot they wish to see and then share this with other users via either a URL or by QR code. Various types of plots can be created, including simple time series, data plotted as a function of orbital location, and time versus L-Shell. We discuss the new Van Allen Probes Science Gateway and the Space Weather Data Pipeline.

Modeling Pacing Behavior and Test Speededness Using Latent Growth Curve Models

ERIC Educational Resources Information Center

Kahraman, Nilufer; Cuddy, Monica M.; Clauser, Brian E.

2013-01-01

This research explores the usefulness of latent growth curve modeling in the study of pacing behavior and test speededness. Examinee response times from a high-stakes, computerized examination, collected before and after the examination was subjected to a timing change, were analyzed using a series of latent growth curve models to detect…

Side scatter versus CD45 flow cytometric plot can distinguish acute leukaemia subtypes.

PubMed

Saksena, Annapurna; Gautam, Parul; Desai, Parth; Gupta, Naresh; Dubey, A P; Singh, Tejinder

2016-05-01

Flow cytometry is an important tool to diagnose acute leukaemia. Attempts are being made to find the minimal number of antibodies for correctly diagnosing acute leukaemia subtypes. The present study was designed to evaluate the analysis of side scatter (SSC) versus CD45 flow dot plot to distinguish acute myeloid leukaemia (AML) from acute lymphoblastic leukaemia (ALL), with minimal immunological markers. One hundred consecutive cases of acute leukaemia were evaluated for blast cluster on SSC versus CD45 plots. The parameters studied included visual shape, CD45 and side scatter expression, continuity with residual granulocytes/lymphocytes/monocytes and ratio of maximum width to maximum height (w/h). The final diagnosis of ALL and AML and their subtypes was made by morphology, cytochemistry and immunophenotyping. Two sample Wilcoxon rank-sum (Mann Whitney) test and Kruskal-Wallis equality-of-populations rank tests were applied to elucidate the significance of the above ratios of blast cluster for diagnosis of ALL, AML and their subtypes. Receiver operating characteristic (ROC) curves were generated and the optimal cut-offs of the w/h ratio to distinguish between ALL and AML determined. Of the 100 cases, 57 of ALL and 43 cases of AML were diagnosed. The median w/h ratio of blast population was 3.8 for ALL and 1 for AML (P<0.001). ROC had area under curve of 0.9772.The optimal cut-off of the w/h ratio for distinction of ALL from AML was found to be 1.6. Our findings suggest that if w/h ratio on SSC versus CD45 plot is less than 1.6, AML may be considered, and if it is more than 1.6, ALL may be diagnosed. Using morphometric analysis of the blast cluster on SSC versus CD45, it was possible to distinguish between ALL and AML, and their subtypes.

Use of individualistic streamflow-vegetation relations along the Fremont River, Utah, USA to assess impacts of flow alteration on wetland and riparian area

USGS Publications Warehouse

Auble, G.T.; Scott, M.L.; Friedman, J.M.

2005-01-01

We analyzed the transverse pattern of vegetation along a reach of the Fremont River in Capitol Reef National Park, Utah, USA using models that support both delineation of wetland extent and projection of the changes in wetland area resulting from upstream hydrologic alteration. We linked stage-discharge relations developed by a hydraulic model to a flow-duration curve derived from the flow history in order to calculate the inundation duration of 361 plots (0.5 × 2 m). Logistic regression was used to relate plant species occurrence in plots to inundation duration. A weighted average of the wetland indicator values of species was used to characterize plots as Aquatic, Wetland, Transitional, or Upland. Finally, we assessed how alterations in the flow duration curve would change the relative widths of these four zones. The wetland indicator values of species and the wetland prevalence index scores of plots were strongly correlated with inundation duration. Our results support the concept that plants classified as wetland species typically occur on sites inundated at least two weeks every two years. The portion of the riparian zone along the high-gradient study reach of the Fremont River that satisfied the vegetation criterion for a regulatory wetland was narrow (2 m wide). Both the unvegetated Aquatic zone (7.8 m) and the Transitional zone (8 m) were substantially wider. The Transitional zone included the maxima of several species and was, therefore, not merely a combination of elements of the Wetland and Upland zones. Multiplicative increases or decreases in streamflow regime produced a wetter, or drier, bottomland vegetation, respectively. Systematic reductions in flow variability reduced the width of both the Wetland and Transitional zones and increased the width of the Upland zone. Our approach is widely applicable to inform water management decisions involving changes in flow regime.

Computer program for plotting and fairing wind-tunnel data

NASA Technical Reports Server (NTRS)

Morgan, H. L., Jr.

1983-01-01

A detailed description of the Langley computer program PLOTWD which plots and fairs experimental wind-tunnel data is presented. The program was written for use primarily on the Langley CDC computer and CALCOMP plotters. The fundamental operating features of the program are that the input data are read and written to a random-access file for use during program execution, that the data for a selected run can be sorted and edited to delete duplicate points, and that the data can be plotted and faired using tension splines, least-squares polynomial, or least-squares cubic-spline curves. The most noteworthy feature of the program is the simplicity of the user-supplied input requirements. Several subroutines are also included that can be used to draw grid lines, zero lines, axis scale values and lables, and legends. A detailed description of the program operational features and each sub-program are presented. The general application of the program is also discussed together with the input and output for two typical plot types. A listing of the program code, user-guide, and output description are presented in appendices. The program has been in use at Langley for several years and has proven to be both easy to use and versatile.

Application of Tryptophan Fluorescence Bandwidth-Maximum Plot in Analysis of Monoclonal Antibody Structure.

PubMed

Huang, Cheng-Yen; Hsieh, Ming-Ching; Zhou, Qinwei

2017-04-01

Monoclonal antibodies have become the fastest growing protein therapeutics in recent years. The stability and heterogeneity pertaining to its physical and chemical structures remain a big challenge. Tryptophan fluorescence has been proven to be a versatile tool to monitor protein tertiary structure. By modeling the tryptophan fluorescence emission envelope with log-normal distribution curves, the quantitative measure can be exercised for the routine characterization of monoclonal antibody overall tertiary structure. Furthermore, the log-normal deconvolution results can be presented as a two-dimensional plot with tryptophan emission bandwidth vs. emission maximum to enhance the resolution when comparing samples or as a function of applied perturbations. We demonstrate this by studying four different monoclonal antibodies, which show the distinction on emission bandwidth-maximum plot despite their similarity in overall amino acid sequences and tertiary structures. This strategy is also used to demonstrate the tertiary structure comparability between different lots manufactured for one of the monoclonal antibodies (mAb2). In addition, in the unfolding transition studies of mAb2 as a function of guanidine hydrochloride concentration, the evolution of the tertiary structure can be clearly traced in the emission bandwidth-maximum plot.

COSP for Windows: Strategies for Rapid Analyses of Cyclic Oxidation Behavior

NASA Technical Reports Server (NTRS)

Smialek, James L.; Auping, Judith V.

2002-01-01

COSP is a publicly available computer program that models the cyclic oxidation weight gain and spallation process. Inputs to the model include the selection of an oxidation growth law and a spalling geometry, plus oxide phase, growth rate, spall constant, and cycle duration parameters. Output includes weight change, the amounts of retained and spalled oxide, the total oxygen and metal consumed, and the terminal rates of weight loss and metal consumption. The present version is Windows based and can accordingly be operated conveniently while other applications remain open for importing experimental weight change data, storing model output data, or plotting model curves. Point-and-click operating features include multiple drop-down menus for input parameters, data importing, and quick, on-screen plots showing one selection of the six output parameters for up to 10 models. A run summary text lists various characteristic parameters that are helpful in describing cyclic behavior, such as the maximum weight change, the number of cycles to reach the maximum weight gain or zero weight change, the ratio of these, and the final rate of weight loss. The program includes save and print options as well as a help file. Families of model curves readily show the sensitivity to various input parameters. The cyclic behaviors of nickel aluminide (NiAl) and a complex superalloy are shown to be properly fitted by model curves. However, caution is always advised regarding the uniqueness claimed for any specific set of input parameters,

Flexural fatigue of short glass fiber reinforced a blend of polyphenylene ether ketone and polyphenylene sulfide

NASA Astrophysics Data System (ADS)

Zhou, Jiang; D'Amore, Alberto; Yang, Yuming; He, Tianbai; Li, Binyao; Nicolais, Luigi

1994-05-01

Flexural fatigue tests were conducted on injection molded glass fiber reinforced a blend of polyphenylene ether ketone and polyphenylene sulfide composite using four-point bending with different stress ratios and different frequencies. The fatigue behavior of this material was described. The constructed S-N curves shift their trends obviously at the maximum cyclic stress being about 80% of the ultimate flexural strength. Examinations of failure surfaces for various loading conditions show that the fatigue failure mechanisms appear to be matrix yielding at high stresses and crack growth at low stresses. Analyses of the fatigue data at various stress ratios reveal that the data at low stress superimpose to form a single curve which is nearly linear when they are plotted as stress range versus number of cycles to failure in bilogarithmic axes, while the data at high stresses also converge to yield a single curve when they are plotted as ( S max S range)1/2 against specimen lifetimes ( S max is the maximum stress and S range is the stress range). These results show that for the studied material the main factor influencing the lifetime is the stress range at low stresses and the parameter ( S max S range)1/2 at high stresses. Comparison of fatigue data in the frequency range of 0.89 7.0 Hz was made, no significant effect of frequency on the fatigue behavior is found.

Numerical study for Darcy-Forchheimer flow of nanofluid due to an exponentially stretching curved surface

NASA Astrophysics Data System (ADS)

Hayat, Tasawar; Haider, Farwa; Muhammad, Taseer; Alsaedi, Ahmed

2018-03-01

Here Darcy-Forchheimer flow of viscous nanofluid with Brownian motion and thermophoresis is addressed. An incompressible viscous liquid saturates the porous space through Darcy-Forchheimer relation. Flow is generated by an exponentially stretching curved surface. System of partial differential equations is converted into ordinary differential system. Nonlinear systems are solved numerically by NDSolve technique. Graphs are plotted for the outcomes of various pertinent variables. Skin friction coefficient and local Nusselt and Sherwood numbers have been physically interpreted. Our results indicate that the local Nusselt and Sherwood numbers are reduced for larger values of local porosity parameter and Forchheimer number.

Quantifying the uncertainty in discharge data using hydraulic knowledge and uncertain gaugings: a Bayesian method named BaRatin

NASA Astrophysics Data System (ADS)

Le Coz, Jérôme; Renard, Benjamin; Bonnifait, Laurent; Branger, Flora; Le Boursicaud, Raphaël; Horner, Ivan; Mansanarez, Valentin; Lang, Michel; Vigneau, Sylvain

2015-04-01

River discharge is a crucial variable for Hydrology: as the output variable of most hydrologic models, it is used for sensitivity analyses, model structure identification, parameter estimation, data assimilation, prediction, etc. A major difficulty stems from the fact that river discharge is not measured continuously. Instead, discharge time series used by hydrologists are usually based on simple stage-discharge relations (rating curves) calibrated using a set of direct stage-discharge measurements (gaugings). In this presentation, we present a Bayesian approach (cf. Le Coz et al., 2014) to build such hydrometric rating curves, to estimate the associated uncertainty and to propagate this uncertainty to discharge time series. The three main steps of this approach are described: (1) Hydraulic analysis: identification of the hydraulic controls that govern the stage-discharge relation, identification of the rating curve equation and specification of prior distributions for the rating curve parameters; (2) Rating curve estimation: Bayesian inference of the rating curve parameters, accounting for the individual uncertainties of available gaugings, which often differ according to the discharge measurement procedure and the flow conditions; (3) Uncertainty propagation: quantification of the uncertainty in discharge time series, accounting for both the rating curve uncertainties and the uncertainty of recorded stage values. The rating curve uncertainties combine the parametric uncertainties and the remnant uncertainties that reflect the limited accuracy of the mathematical model used to simulate the physical stage-discharge relation. In addition, we also discuss current research activities, including the treatment of non-univocal stage-discharge relationships (e.g. due to hydraulic hysteresis, vegetation growth, sudden change of the geometry of the section, etc.). An operational version of the BaRatin software and its graphical interface are made available free of charge on request to the authors. J. Le Coz, B. Renard, L. Bonnifait, F. Branger, R. Le Boursicaud (2014). Combining hydraulic knowledge and uncertain gaugings in the estimation of hydrometric rating curves: a Bayesian approach, Journal of Hydrology, 509, 573-587.

lcps: Light curve pre-selection

NASA Astrophysics Data System (ADS)

Schlecker, Martin

2018-05-01

lcps searches for transit-like features (i.e., dips) in photometric data. Its main purpose is to restrict large sets of light curves to a number of files that show interesting behavior, such as drops in flux. While lcps is adaptable to any format of time series, its I/O module is designed specifically for photometry of the Kepler spacecraft. It extracts the pre-conditioned PDCSAP data from light curves files created by the standard Kepler pipeline. It can also handle csv-formatted ascii files. lcps uses a sliding window technique to compare a section of flux time series with its surroundings. A dip is detected if the flux within the window is lower than a threshold fraction of the surrounding fluxes.

Reinterpretation of curved Hammett plots in reaction of nucleophiles with aryl benzoates: change in rate-determining step or mechanism versus ground-state stabilization.

PubMed

Um, Ik-Hwan; Han, Hyun-Joo; Ahn, Jung-Ae; Kang, Swan; Buncel, Erwin

2002-11-29

A kinetic study is reported for the reaction of the anionic nucleophiles OH-, CN-, and N 3 - with aryl benzoates containing substituents on the benzoyl as well as the aryloxy moiety, in 80 mol % H2O - 20 mol % dimethyl sulfoxide at 25.0 degrees C. Hammett log k vs sigma plots for these systems are consistently nonlinear. However, a possible traditional explanation in terms of a mechanism involving a tetrahedral intermediate with curvature resulting from a change in rate-determining step is considered but rejected. The proposed explanation involves ground-state stabilization through resonance interaction between the benzoyl substituent and the electrophilic carbonyl center in the two-stage mechanism. Accordingly, the data are nicely accommodated on the basis of the Yukawa-Tsuno equation, which gives linear plots for all three nuceophiles. Literature reports of the mechanism of acyl transfer processes are reconsidered in this light.

Nonlinear model updating applied to the IMAC XXXII Round Robin benchmark system

NASA Astrophysics Data System (ADS)

Kurt, Mehmet; Moore, Keegan J.; Eriten, Melih; McFarland, D. Michael; Bergman, Lawrence A.; Vakakis, Alexander F.

2017-05-01

We consider the application of a new nonlinear model updating strategy to a computational benchmark system. The approach relies on analyzing system response time series in the frequency-energy domain by constructing both Hamiltonian and forced and damped frequency-energy plots (FEPs). The system parameters are then characterized and updated by matching the backbone branches of the FEPs with the frequency-energy wavelet transforms of experimental and/or computational time series. The main advantage of this method is that no nonlinearity model is assumed a priori, and the system model is updated solely based on simulation and/or experimental measured time series. By matching the frequency-energy plots of the benchmark system and its reduced-order model, we show that we are able to retrieve the global strongly nonlinear dynamics in the frequency and energy ranges of interest, identify bifurcations, characterize local nonlinearities, and accurately reconstruct time series. We apply the proposed methodology to a benchmark problem, which was posed to the system identification community prior to the IMAC XXXII (2014) and XXXIII (2015) Conferences as a "Round Robin Exercise on Nonlinear System Identification". We show that we are able to identify the parameters of the non-linear element in the problem with a priori knowledge about its position.

PLOT3D- DRAWING THREE DIMENSIONAL SURFACES

NASA Technical Reports Server (NTRS)

Canright, R. B.

1994-01-01

PLOT3D is a package of programs to draw three-dimensional surfaces of the form z = f(x,y). The function f and the boundary values for x and y are the input to PLOT3D. The surface thus defined may be drawn after arbitrary rotations. However, it is designed to draw only functions in rectangular coordinates expressed explicitly in the above form. It cannot, for example, draw a sphere. Output is by off-line incremental plotter or online microfilm recorder. This package, unlike other packages, will plot any function of the form z = f(x,y) and portrays continuous and bounded functions of two independent variables. With curve fitting; however, it can draw experimental data and pictures which cannot be expressed in the above form. The method used is division into a uniform rectangular grid of the given x and y ranges. The values of the supplied function at the grid points (x, y) are calculated and stored; this defines the surface. The surface is portrayed by connecting successive (y,z) points with straight-line segments for each x value on the grid and, in turn, connecting successive (x,z) points for each fixed y value on the grid. These lines are then projected by parallel projection onto the fixed yz-plane for plotting. This program has been implemented on the IBM 360/67 with on-line CDC microfilm recorder.

A stand density management diagram for sawtimber-sized mixed upland central hardwoods

Treesearch

J.A., Jr. Kershaw; B.C. Fischer

1991-01-01

Data from 190 CFI plots located in southern and west-central Indiana are used to develop a stand density diagram for sawtimber-sized mixed upland hardwoods in the Central States. The stand density diagram utilizes the concepts of self-thinning to establish a maximum size-density curve, and the stocking standards of Gingrich (1967) to formulate imtermediate stocking...

Handling of computational in vitro/in vivo correlation problems by Microsoft Excel: I. Principles and some general algorithms.

PubMed

Langenbucher, Frieder

2002-01-01

Most computations in the field of in vitro/in vivo correlations can be handled directly by Excel worksheets, without the need for specialized software. Following a summary of Excel features, applications are illustrated for numerical computation of AUC and Mean, Wagner-Nelson and Loo-Riegelman absorption plots, and polyexponential curve fitting.

A new methodology for free wake analysis using curved vortex elements

NASA Technical Reports Server (NTRS)

Bliss, Donald B.; Teske, Milton E.; Quackenbush, Todd R.

1987-01-01

A method using curved vortex elements was developed for helicopter rotor free wake calculations. The Basic Curve Vortex Element (BCVE) is derived from the approximate Biot-Savart integration for a parabolic arc filament. When used in conjunction with a scheme to fit the elements along a vortex filament contour, this method has a significant advantage in overall accuracy and efficiency when compared to the traditional straight-line element approach. A theoretical and numerical analysis shows that free wake flows involving close interactions between filaments should utilize curved vortex elements in order to guarantee a consistent level of accuracy. The curved element method was implemented into a forward flight free wake analysis, featuring an adaptive far wake model that utilizes free wake information to extend the vortex filaments beyond the free wake regions. The curved vortex element free wake, coupled with this far wake model, exhibited rapid convergence, even in regions where the free wake and far wake turns are interlaced. Sample calculations are presented for tip vortex motion at various advance ratios for single and multiple blade rotors. Cross-flow plots reveal that the overall downstream wake flow resembles a trailing vortex pair. A preliminary assessment shows that the rotor downwash field is insensitive to element size, even for relatively large curved elements.

At what age do biomedical scientists do their best work?

PubMed

Falagas, Matthew E; Ierodiakonou, Vrettos; Alexiou, Vangelis G

2008-12-01

Several human characteristics that influence scientific research performance, including set goals, mental and physical abilities, education, and experience, may vary considerably during the life cycle of scientists. We sought to answer the question of whether high-quality research productivity is associated with investigator's age. We randomly selected 300 highly cited scientists (50 from each of 6 different biomedical fields, specifically immunology, microbiology, neuroscience, psychology-psychiatry, clinical medicine, and biology-biochemistry). Then, we identified the top 5 highly cited articles (within 10 yr after publication adjusted for the expansion of the literature) as first author of each of them. Subsequently, we plotted the distribution of the 1500 analyzed articles of the 300 studied scientists in the eight 5-year intervals of investigator's age during the year of article publication (21-25 to 55-60 yr of age), adjusted for person-years of contribution of each scientist in the various age groups. Highly cited research productivity plotted a curve that peaked at the age group of 31-35 yr of age and then gradually decreased with advancing age. However, a considerable proportion of this highly cited research was produced by older scientists (in almost 20% of the analyzed articles, researchers were older than 50 yr). The results were similar in another analysis of the single most cited article of each studied scientist. In conclusion, high-quality scientific productivity in the biomedical fields as a function of investigator's age plots an inverted U-shaped curve, in which significant decreases take place from around 40 yr of age and beyond.

The application of reduced absorption cross section on the identification of the compounds with similar function-groups

NASA Astrophysics Data System (ADS)

Yu, Fei; Zuo, Jian; Mu, Kai-jun; Zhang, Zhen-wei; Zhang, Liang-liang; Zhang, Lei-wei; Zhang, Cun-lin

2013-08-01

Terahertz spectroscopy is a powerful tool for materials investigation. The low frequency vibrations were usually investigated by means of absorption coefficient regardless of the refractive index. It leads to the disregard of some inherent low-frequency vibrational information of the chemical compounds. Moreover, due to the scattering inside the sample, there are some distortions of the absorption features, so that the absorption dependent material identification is not valid enough. Here, a statistical parameter named reduced absorption cross section (RACS) is introduced. This can not only help us investigate the molecular dynamics but also distinguish one chemical compound with another which has similar function-groups. Experiments are carried out on L-Tyrosine and L-Phenylalanine and the different mass ratios of their mixtures as an example of the application of RACS. The results come out that the RACS spectrum of L-Tyrosine and L-Phenylalanine reserve the spectral fingerprint information of absorption spectrum. The log plot of RACSs of the two amino acids show power-law behavior σR(~ν) ~ (ν~α), and there is a linear relation between the wavenumber and the RACS in the double logarithmic plot. The exponents α, at the same time, are the slopes of the RACS curves in the double logarithmic plot. The big differences of the exponents α between the two amino acids and their mixtures can be seen visually from the slopes of the RACS curves. So we can use RACS analytical method to distinguish some complex compounds with similar function-groups and mixtures from another which has similar absorption peaks in THz region.

Corticothalamic feedback enhances stimulus response precision in the visual system

PubMed Central

Andolina, Ian M.; Jones, Helen E.; Wang, Wei; Sillito, Adam M.

2007-01-01

There is a tightly coupled bidirectional interaction between visual cortex and visual thalamus [lateral geniculate nucleus (LGN)]. Using drifting sinusoidal grating stimuli, we compared the response of cells in the LGN with and without feedback from the visual cortex. Raster plots revealed a striking difference in the response pattern of cells with and without feedback. This difference was reflected in the results from computing vector sum plots and the ratio of zero harmonic to the fundamental harmonic of the fast Fourier transform (FFT) for these responses. The variability of responses assessed by using the Fano factor was also different for the two groups, with the cells without feedback showing higher variability. We examined the covariance of these measures between pairs of simultaneously recorded cells with and without feedback, and they were much more strongly positively correlated with feedback. We constructed orientation tuning curves from the central 5 ms in the raw cross-correlograms of the outputs of pairs of LGN cells, and these curves revealed much sharper tuning with feedback. We discuss the significance of these data for cortical function and suggest that the precision in stimulus-linked firing in the LGN appears as an emergent factor from the corticothalamic interaction. PMID:17237220

Surface Plasmon Waves on Thin Metal Films.

NASA Astrophysics Data System (ADS)

Craig, Alan Ellsworth

Surface-plasmon polaritons propagating on thin metal films bounded by dielectrics of nearly equal refractive indexes comprise two bound modes. Calculations indicate that, while the modes are degenerate on thick films, both the real and the imaginary components of the propagation constants for the modes split into two branches on successively thinner films. Considering these non-degenerate modes, the mode exhibiting a symmetric (antisymmetric) transverse profile of the longitudinally polarized electric field component, has propagation constant components both of which increase (decrease) with decreasing film thickness. Theoretical propagation constant eigenvalue (PCE) curves have been plotted which delineate this dependence of both propagation constant components on film thickness. By means of a retroreflecting, hemispherical glass coupler in an attenuated total reflection (ATR) configuration, light of wavelength 632.8 nm coupled to the modes of thin silver films deposited on polished glass substrates. Lorentzian lineshape dips in the plots of reflectance vs. angle of incidence indicate the presence of the plasmon modes. The real and imaginary components of the propagation constraints (i.e., the propagation constant and loss coefficient) were calculated from the angular positions and widths of the ATR resonances recorded. Films of several thicknesses were probed. Results which support the theoretically predicted curves were reported.

The complex phase gradient method applied to leaky Lamb waves.

PubMed

Lenoir, O; Conoir, J M; Izbicki, J L

2002-10-01

The classical phase gradient method applied to the characterization of the angular resonances of an immersed elastic plate, i.e., the angular poles of its reflection coefficient R, was proved to be efficient when their real parts are close to the real zeros of R and their imaginary parts are not too large compared to their real parts. This method consists of plotting the partial reflection coefficient phase derivative with respect to the sine of the incidence angle, considered as real, versus incidence angle. In the vicinity of a resonance, this curve exhibits a Breit-Wigner shape, whose minimum is located at the pole real part and whose amplitude is the inverse of its imaginary part. However, when the imaginary part is large, this method is not sufficiently accurate compared to the exact calculation of the complex angular root. An improvement of this method consists of plotting, in 3D, in the complex angle plane and at a given frequency, the angular phase derivative with respect to the real part of the sine of the incidence angle, considered as complex. When the angular pole is reached, the 3D curve shows a clear-cut transition whose position is easily obtained.

Water solubility enhancements of DDT and trichlorobenzene by some surfactants below and above the critical micelle concentration

USGS Publications Warehouse

Kile, D.E.; Chiou, C.T.

1989-01-01

Water solubility enhancements of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT) and 1,2,3-trichlorobenzene (TCB) by aqueous surfactants below and above their critical micelle concentrations (CMCs) have been studied at room temperature with the following surfactants: Triton X-100, Triton X-114, Triton X-405, Brij 35, sodium dodecyl sulfate, and cetyltrimethylammonium bromide. While the solubilities of DDT and TCB are greatly enhanced by all surfactants above the measured CMC, DDT also exhibits significant solubility enhancements below the CMC of the molecularly nonhomogeneous surfactants (the Triton series and Brij 35). The plot of the apparent DDT solubility against the concentration of Triton and Brij surfactants shows an uprising curve below the nominal CMC, which is attributed to the successive micellization of the heterogeneous monomer species. Above the CMC, the enhancement effect with the nonionic surfactants is closely proportional to the nonpolar chain content of the surfactant, whereas the effect with the ionic surfactants is less accountable in terms of their nonpolar chain contents. The solubilization power of a micelle relative to a bulk solvent is evaluated by a comparison of the observed micelle-water and solvent-water partition coefficients.

Predictive Temperature Equations for Three Sites at the Grand Canyon

NASA Astrophysics Data System (ADS)

McLaughlin, Katrina Marie Neitzel

Climate data collected at a number of automated weather stations were used to create a series of predictive equations spanning from December 2009 to May 2010 in order to better predict the temperatures along hiking trails within the Grand Canyon. The central focus of this project is how atmospheric variables interact and can be combined to predict the weather in the Grand Canyon at the Indian Gardens, Phantom Ranch, and Bright Angel sites. Through the use of statistical analysis software and data regression, predictive equations were determined. The predictive equations are simple or multivariable best fits that reflect the curvilinear nature of the data. With data analysis software curves resulting from the predictive equations were plotted along with the observed data. Each equation's reduced chi2 was determined to aid the visual examination of the predictive equations' ability to reproduce the observed data. From this information an equation or pair of equations was determined to be the best of the predictive equations. Although a best predictive equation for each month and season was determined for each site, future work may refine equations to result in a more accurate predictive equation.

A simple method of equine limb force vector analysis and its potential applications.

PubMed

Hobbs, Sarah Jane; Robinson, Mark A; Clayton, Hilary M

2018-01-01

Ground reaction forces (GRF) measured during equine gait analysis are typically evaluated by analyzing discrete values obtained from continuous force-time data for the vertical, longitudinal and transverse GRF components. This paper describes a simple, temporo-spatial method of displaying and analyzing sagittal plane GRF vectors. In addition, the application of statistical parametric mapping (SPM) is introduced to analyse differences between contra-lateral fore and hindlimb force-time curves throughout the stance phase. The overall aim of the study was to demonstrate alternative methods of evaluating functional (a)symmetry within horses. GRF and kinematic data were collected from 10 horses trotting over a series of four force plates (120 Hz). The kinematic data were used to determine clean hoof contacts. The stance phase of each hoof was determined using a 50 N threshold. Vertical and longitudinal GRF for each stance phase were plotted both as force-time curves and as force vector diagrams in which vectors originating at the centre of pressure on the force plate were drawn at intervals of 8.3 ms for the duration of stance. Visual evaluation was facilitated by overlay of the vector diagrams for different limbs. Summary vectors representing the magnitude (VecMag) and direction (VecAng) of the mean force over the entire stance phase were superimposed on the force vector diagram. Typical measurements extracted from the force-time curves (peak forces, impulses) were compared with VecMag and VecAng using partial correlation (controlling for speed). Paired samples t -tests (left v. right diagonal pair comparison and high v. low vertical force diagonal pair comparison) were performed on discrete and vector variables using traditional methods and Hotelling's T 2 tests on normalized stance phase data using SPM. Evidence from traditional statistical tests suggested that VecMag is more influenced by the vertical force and impulse, whereas VecAng is more influenced by the longitudinal force and impulse. When used to evaluate mean data from the group of ten sound horses, SPM did not identify differences between the left and right contralateral limb pairs or between limb pairs classified according to directional asymmetry. When evaluating a single horse, three periods were identified during which differences in the forces between the left and right forelimbs exceeded the critical threshold ( p  < .01). Traditional statistical analysis of 2D GRF peak values, summary vector variables and visual evaluation of force vector diagrams gave harmonious results and both methods identified the same inter-limb asymmetries. As alpha was more tightly controlled using SPM, significance was only found in the individual horse although T 2 plots followed the same trends as discrete analysis for the group. The techniques of force vector analysis and SPM hold promise for investigations of sidedness and asymmetry in horses.

Process air quality data

NASA Technical Reports Server (NTRS)

Butler, C. M.; Hogge, J. E.

1978-01-01

Air quality sampling was conducted. Data for air quality parameters, recorded on written forms, punched cards or magnetic tape, are available for 1972 through 1975. Computer software was developed to (1) calculate several daily statistical measures of location, (2) plot time histories of data or the calculated daily statistics, (3) calculate simple correlation coefficients, and (4) plot scatter diagrams. Computer software was developed for processing air quality data to include time series analysis and goodness of fit tests. Computer software was developed to (1) calculate a larger number of daily statistical measures of location, and a number of daily monthly and yearly measures of location, dispersion, skewness and kurtosis, (2) decompose the extended time series model and (3) perform some goodness of fit tests. The computer program is described, documented and illustrated by examples. Recommendations are made for continuation of the development of research on processing air quality data.

Evaluation of the Effects of Iron Oxides on Soil Reducing Conditions and Methane Generation in Cambodian Wetland Rice Fields

NASA Astrophysics Data System (ADS)

Weaver, M.; Benner, S.; Fendorf, S.; Sampson, M.; Leng, M.

2007-12-01

Atmospheric concentrations of methane have been steadily increasing over the last 100 years, which has given rise to research of wetland rice fields, recently identified as a major anthropomorphic source of methane. Establishment of experimental soil pots, cultivating an aromatic early variety rice strain in the Kean Svay District of Cambodia, have recently been carried out to evaluate methods to minimize methane release by promoting redox buffering by iron oxides. In the first series of experiments, iron oxides were added to the soils and the rate of change in reducing conditions and methanogenesis onset was monitored. In the second series of experiments, plots are subject to periodic drying cycles to promote rejuvenation of buffering iron oxides. Initial results indicate a delay in the onset of methanogenesis, and overall methane generation, in plots where initial iron oxides concentrations are elevated.

INCA- INTERACTIVE CONTROLS ANALYSIS

NASA Technical Reports Server (NTRS)

Bauer, F. H.

1994-01-01

The Interactive Controls Analysis (INCA) program was developed to provide a user friendly environment for the design and analysis of linear control systems, primarily feedback control systems. INCA is designed for use with both small and large order systems. Using the interactive graphics capability, the INCA user can quickly plot a root locus, frequency response, or time response of either a continuous time system or a sampled data system. The system configuration and parameters can be easily changed, allowing the INCA user to design compensation networks and perform sensitivity analysis in a very convenient manner. A journal file capability is included. This stores an entire sequence of commands, generated during an INCA session into a file which can be accessed later. Also included in INCA are a context-sensitive help library, a screen editor, and plot windows. INCA is robust to VAX-specific overflow problems. The transfer function is the basic unit of INCA. Transfer functions are automatically saved and are available to the INCA user at any time. A powerful, user friendly transfer function manipulation and editing capability is built into the INCA program. The user can do all transfer function manipulations and plotting without leaving INCA, although provisions are made to input transfer functions from data files. By using a small set of commands, the user may compute and edit transfer functions, and then examine these functions by using the ROOT_LOCUS, FREQUENCY_RESPONSE, and TIME_RESPONSE capabilities. Basic input data, including gains, are handled as single-input single-output transfer functions. These functions can be developed using the function editor or by using FORTRAN- like arithmetic expressions. In addition to the arithmetic functions, special functions are available to 1) compute step, ramp, and sinusoid functions, 2) compute closed loop transfer functions, 3) convert from S plane to Z plane with optional advanced Z transform, and 4) convert from Z plane to W plane and back. These capabilities allow the INCA user to perform block diagram algebraic manipulations quickly for functions in the S, Z, and W domains. Additionally, a versatile digital control capability has been included in INCA. Special plane transformations allow the user to easily convert functions from one domain to another. Other digital control capabilities include: 1) totally independent open loop frequency response analyses on a continuous plant, discrete control system with a delay, 2) advanced Z-transform capability for systems with delays, and 3) multirate sampling analyses. The current version of INCA includes Dynamic Functions (which change when a parameter changes), standard filter generation, PD and PID controller generation, incorporation of the QZ-algorithm (function addition, inverse Laplace), and describing functions that allow the user to calculate the gain and phase characteristics of a nonlinear device. The INCA graphic modes provide the user with a convenient means to document and study frequency response, time response, and root locus analyses. General graphics features include: 1) zooming and dezooming, 2) plot documentation, 3) a table of analytic computation results, 4) multiple curves on the same plot, and 5) displaying frequency and gain information for a specific point on a curve. Additional capabilities in the frequency response mode include: 1) a full complement of graphical methods Bode magnitude, Bode phase, Bode combined magnitude and phase, Bode strip plots, root contour plots, Nyquist, Nichols, and Popov plots; 2) user selected plot scaling; and 3) gain and phase margin calculation and display. In the time response mode, additional capabilities include: 1) support for inverse Laplace and inverse Z transforms, 2) support for various input functions, 3) closed loop response evaluation, 4) loop gain sensitivity analyses, 5) intersample time response for discrete systems using the advanced Z transform, and 6) closed loop time response using mixed plane (S, Z, W) operations with delay. A Graphics mode command was added to the current version of INCA, version 3.13, to produce Metafiles (graphic files) of the currently displayed plot. The metafile can be displayed and edited using the QPLOT Graphics Editor and Replotter for Metafiles (GERM) program included with the INCA package. The INCA program is written in Pascal and FORTRAN for interactive or batch execution and has been implemented on a DEC VAX series computer under VMS. Both source code and executable code are supplied for INCA. Full INCA graphics capabilities are supported for various Tektronix 40xx and 41xx terminals; DEC VT graphics terminals; many PC and Macintosh terminal emulators; TEK014 hardcopy devices such as the LN03 Laserprinter; and bit map graphics external hardcopy devices. Also included for the TEK4510 rasterizer users are a multiple copy feature, a wide line feature, and additional graphics fonts. The INCA program was developed in 1985, Version 2.04 was released in 1986, Version 3.00 was released in 1988, and Version 3.13 was released in 1989. An INCA version 2.0X conversion program is included.

Learning curve in robotic rectal cancer surgery: current state of affairs.

PubMed

Jiménez-Rodríguez, Rosa M; Rubio-Dorado-Manzanares, Mercedes; Díaz-Pavón, José Manuel; Reyes-Díaz, M Luisa; Vazquez-Monchul, Jorge Manuel; Garcia-Cabrera, Ana M; Padillo, Javier; De la Portilla, Fernando

2016-12-01

Robotic-assisted rectal cancer surgery offers multiple advantages for surgeons, and it seems to yield the same clinical outcomes as regards the short-time follow-up of patients compared to conventional laparoscopy. This surgical approach emerges as a technique aiming at overcoming the limitations posed by rectal cancer and other surgical fields of difficult access, in order to obtain better outcomes and a shorter learning curve. A systematic review of the literature of robot-assisted rectal surgery was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The search was conducted in October 2015 in PubMed, MEDLINE and the Cochrane Central Register of Controlled Trials, for articles published in the last 10 years and pertaining the learning curve of robotic surgery for colorectal cancer. It consisted of the following key words: "rectal cancer/learning curve/robotic-assisted laparoscopic surgery". A total of 34 references were identified, but only 9 full texts specifically addressed the analysis of the learning curve in robot-assisted rectal cancer surgery, 7 were case series and 2 were non-randomised case-comparison series. Eight papers used the cumulative sum (CUSUM) method, and only one author divided the series into two groups to compare both. The mean number of cases for phase I of the learning curve was calculated to be 29.7 patients; phase II corresponds to a mean number 37.4 patients. The mean number of cases required for the surgeon to be classed as an expert in robotic surgery was calculated to be 39 patients. Robotic advantages could have an impact on learning curve for rectal cancer and lower the number of cases that are necessary for rectal resections.

The Biasing Effects of Unmodeled ARMA Time Series Processes on Latent Growth Curve Model Estimates

ERIC Educational Resources Information Center

Sivo, Stephen; Fan, Xitao; Witta, Lea

2005-01-01

The purpose of this study was to evaluate the robustness of estimated growth curve models when there is stationary autocorrelation among manifest variable errors. The results suggest that when, in practice, growth curve models are fitted to longitudinal data, alternative rival hypotheses to consider would include growth models that also specify…

Visualizing dispersive features in 2D image via minimum gradient method

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

He, Yu; Wang, Yan; Shen, Zhi -Xun

Here, we developed a minimum gradient based method to track ridge features in a 2D image plot, which is a typical data representation in many momentum resolved spectroscopy experiments. Through both analytic formulation and numerical simulation, we compare this new method with existing DC (distribution curve) based and higher order derivative based analyses. We find that the new method has good noise resilience and enhanced contrast especially for weak intensity features and meanwhile preserves the quantitative local maxima information from the raw image. An algorithm is proposed to extract 1D ridge dispersion from the 2D image plot, whose quantitative applicationmore » to angle-resolved photoemission spectroscopy measurements on high temperature superconductors is demonstrated.« less

Visualizing dispersive features in 2D image via minimum gradient method

DOE PAGES

He, Yu; Wang, Yan; Shen, Zhi -Xun

2017-07-24

Here, we developed a minimum gradient based method to track ridge features in a 2D image plot, which is a typical data representation in many momentum resolved spectroscopy experiments. Through both analytic formulation and numerical simulation, we compare this new method with existing DC (distribution curve) based and higher order derivative based analyses. We find that the new method has good noise resilience and enhanced contrast especially for weak intensity features and meanwhile preserves the quantitative local maxima information from the raw image. An algorithm is proposed to extract 1D ridge dispersion from the 2D image plot, whose quantitative applicationmore » to angle-resolved photoemission spectroscopy measurements on high temperature superconductors is demonstrated.« less

Precipitation extremes on multiple timescales - Bartlett-Lewis rectangular pulse model and intensity-duration-frequency curves

NASA Astrophysics Data System (ADS)

Ritschel, Christoph; Ulbrich, Uwe; Névir, Peter; Rust, Henning W.

2017-12-01

For several hydrological modelling tasks, precipitation time series with a high (i.e. sub-daily) resolution are indispensable. The data are, however, not always available, and thus model simulations are used to compensate. A canonical class of stochastic models for sub-daily precipitation are Poisson cluster processes, with the original Bartlett-Lewis (OBL) model as a prominent representative. The OBL model has been shown to well reproduce certain characteristics found in observations. Our focus is on intensity-duration-frequency (IDF) relationships, which are of particular interest in risk assessment. Based on a high-resolution precipitation time series (5 min) from Berlin-Dahlem, OBL model parameters are estimated and IDF curves are obtained on the one hand directly from the observations and on the other hand from OBL model simulations. Comparing the resulting IDF curves suggests that the OBL model is able to reproduce the main features of IDF statistics across several durations but cannot capture rare events (here an event with a return period larger than 1000 years on the hourly timescale). In this paper, IDF curves are estimated based on a parametric model for the duration dependence of the scale parameter in the generalized extreme value distribution; this allows us to obtain a consistent set of curves over all durations. We use the OBL model to investigate the validity of this approach based on simulated long time series.

Congenital unilateral absence of the upper extremity may give rise to a specific kind of thoracolumbar curve.

PubMed

Olgun, Z Deniz; Demirkiran, Gokhan; Polly, David; Yazici, Muharrem

2018-03-01

There is an increased incidence of scoliosis in patients with congenital malformations of the upper extremity even in the absence of overt vertebral abnormalities. In this case series, we summarize the curve characteristics of four patients presenting to two spine surgery clinics with unilateral amelia or phocomelia and a progressive scoliotic curve with the apex on the side of deficiency. All patients required orthopedic intervention for their curves. Amelia and phocomelia are severe congenital malformations of the upper limb affecting trunk balance and, conceivably, causing scoliosis with the absence of counterbalancing weight on the affected side. The combination of upper limb absence and same-sided scoliosis in these patients may provide a clue of the mechanical factors causing scoliosis in other disorders. In this article, we attempt to define this exceptional deformity, theorize on its etiology, and draw attention to this particular combination of problems. Case series; Level IV.

Changes in airway configuration with different head and neck positions using magnetic resonance imaging of normal airways: a new concept with possible clinical applications.

PubMed

Greenland, K B; Edwards, M J; Hutton, N J; Challis, V J; Irwin, M G; Sleigh, J W

2010-11-01

The sniffing position is often considered optimal for direct laryngoscopy. Another concept of airway configuration involving a laryngeal vestibule axis and two curves has also been suggested. We investigated whether this theory can be supported mathematically and if it supports the sniffing position as being optimal for direct laryngoscopy. Magnetic resonance imaging scans were performed in 42 normal adult volunteers. The airway passage was divided into two curves-primary (oro-pharyngeal curve) and secondary (pharyngo-glotto-tracheal curve). Airway configuration was evaluated in the neutral, extension, head lift, and sniffing positions. The airway passage, point of inflection (where the two curves meet), its tangent, and the line of sight were plotted on each scan. The point of inflection lay within the laryngeal vestibule in all positions. The head lift and sniffing positions caused the tangent to the point of inflection to approximate the horizontal plane. The sniffing, extension, and head lift positions caused a reduction in the area between the line of sight and the airway curve compared with the neutral position. A two-curve theory is proposed as a basis for explaining airway configuration. The changes in these curves with head and neck positioning support the sniffing position as optimal for direct laryngoscopy. Application of this new concept to other forms of laryngoscopy should be investigated.

Impedance and modulus spectroscopic study of nano hydroxyapatite

NASA Astrophysics Data System (ADS)

Jogiya, B. V.; Jethava, H. O.; Tank, K. P.; Raviya, V. R.; Joshi, M. J.

2016-05-01

Hydroxyapatite (Ca10 (PO4)6 (OH)2, HAP) is the main inorganic component of the hard tissues in bones and also important material for orthopedic and dental implant applications. Nano HAP is of great interest due to its various bio-medical applications. In the present work the nano HAP was synthesized by using surfactant mediated approach. Structure and morphology of the synthesized nano HAP was examined by the Powder XRD and TEM. Impedance study was carried out on pelletized sample in a frequency range of 100Hz to 20MHz at room temperature. The variation of dielectric constant, dielectric loss, and a.c. conductivity with frequency of applied field was studied. The Nyquist plot as well as modulus plot was drawn. The Nyquist plot showed two semicircle arcs, which indicated the presence of grain and grain boundary effect in the sample. The typical behavior of the Nyquist plot was represented by equivalent circuit having two parallel RC combinations in series.

Diesel-Powered Heavy-Duty Refrigeration Unit Noise

DOT National Transportation Integrated Search

1976-01-01

A series of noise measurements were performed on a diesel-powered heavy-duty refrigeration unit. Noise survey information collected included: polar plots of the 'A Weighted' noise levels of the unit under maximum and minimum load conditions; a linear...

An evaluation of the accuracy of modeled and computed streamflow time-series data for the Ohio River at Hannibal Lock and Dam and at a location upstream from Sardis, Ohio

USGS Publications Warehouse

Koltun, G.F.

2015-01-01

Streamflow hydrographs were plotted for modeled/computed time series for the Ohio River near the USGS Sardis gage and the Ohio River at the Hannibal Lock and Dam. In general, the time series at these two locations compared well. Some notable differences include the exclusive presence of short periods of negative streamflows in the USGS 15-minute time-series data for the gage on the Ohio River above Sardis, Ohio, and the occurrence of several peak streamflows in the USACE gate/hydropower time series for the Hannibal Lock and Dam that were appreciably larger than corresponding peaks in the other time series, including those modeled/computed for the downstream Sardis gage

Analyzing Landsat time-series data across adjacent path/rows and across multiple cycles of FIA: Lessons learned in southern Missouri

Treesearch

Mark Nelson; Sean Healey; W. Keith Moser; Mark Hansen; Warren Cohen; Mark Hatfield; Nancy Thomas; Jeff Masek

2009-01-01

The North American Forest Dynamics (NAFD) Program is assessing disturbance and regrowth in the forests of the continent. These forest dynamics are interpreted from per-pixel estimates of forest biomass, which are produced for a time series of Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced TM Plus images. Image data are combined with sample plot data from the...

Zeus++ - A GUI-Based Flowfield Analysis Tool, Version 1.0, User’s Manual

DTIC Science & Technology

1999-02-01

A.B. and Priolo, F.J., Personal Communication and unpublished documentation. 9 . Tecplot v7.0 Plotting Package, Amtec Engineering, 1998. lO.Hymer... 9 . SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 5. FUNDING NUMBERS 8. PERFORMING ORGANIZATION REPORT NUMBER NSWCDD/TR-98/147 10...12 7 VON KARMAN OGIVE PARAMETERS 13 HAACK SERIES NOSE PARAMETERS 13 9 POWER SERIES NOSE PARAMETERS 14 10 MISCELLANEOUS OPTIONS 15 11

A new parametric method to smooth time-series data of metabolites in metabolic networks.

PubMed

Miyawaki, Atsuko; Sriyudthsak, Kansuporn; Hirai, Masami Yokota; Shiraishi, Fumihide

2016-12-01

Mathematical modeling of large-scale metabolic networks usually requires smoothing of metabolite time-series data to account for measurement or biological errors. Accordingly, the accuracy of smoothing curves strongly affects the subsequent estimation of model parameters. Here, an efficient parametric method is proposed for smoothing metabolite time-series data, and its performance is evaluated. To simplify parameter estimation, the method uses S-system-type equations with simple power law-type efflux terms. Iterative calculation using this method was found to readily converge, because parameters are estimated stepwise. Importantly, smoothing curves are determined so that metabolite concentrations satisfy mass balances. Furthermore, the slopes of smoothing curves are useful in estimating parameters, because they are probably close to their true behaviors regardless of errors that may be present in the actual data. Finally, calculations for each differential equation were found to converge in much less than one second if initial parameters are set at appropriate (guessed) values. Copyright © 2016 Elsevier Inc. All rights reserved.

THE EFFECTS OF VARIATIONS IN THE CONCENTRATION OF OXYGEN AND OF GLUCOSE ON DARK ADAPTATION

PubMed Central

McFarland, R. A.; Forbes, W. H.

1940-01-01

In this study we have analyzed the effects of variations in the concentrations of oxygen and of blood sugar on light sensitivity; i.e. dark adaptation. The experiments were carried out in an air-conditioned light-proof chamber where the concentrations of oxygen could be changed by dilution with nitrogen or by inhaling oxygen from a cylinder. The blood sugar was lowered by the injection of insulin and raised by the ingestion of glucose. The dark adaptation curves were plotted from data secured with an apparatus built according to specifications outlined by Hecht and Shlaer. During each experiment, observations were first made in normal air with the subject under basal conditions followed by one, and in most instances two, periods under the desired experimental conditions involving either anoxia or hyper- or hypoglycemia or variations in both the oxygen tension and blood sugar at the same time. 1. Dark adaptation curves were plotted (threshold against time) in normal air and compared with those obtained while inhaling lowered concentrations of oxygen. A decrease in sensitivity was observed with lowered oxygen tensions. Both the rod and cone portions of the curves were influenced in a similar way. These effects were counteracted by inhaling oxygen, the final rod thresholds returning to about the level of the normal base line in air or even below it within 2 to 3 minutes. The impairment was greatest for those with a poorer tolerance for low O2. Both the inter- and intra-individual variability in thresholds increased significantly at the highest altitude. 2. In a second series of tests control curves were obtained in normal air. Then while each subject remained dark adapted, the concentrations of oxygen were gradually decreased. The regeneration of visual purple was apparently complete during the 40 minutes of dark adaptation, yet in each case the thresholds continued to rise in direct proportion to the degree of anoxia. The inhalation of oxygen from a cylinder quickly counteracted the effects for the thresholds returned to the original control level within 2 to 3 minutes. 3. In experiments where the blood sugar was raised by the ingestion of glucose in normal air, no significant changes in the thresholds were observed except when the blood sugar was rapidly falling toward the end of the glucose tolerance tests. However, when glucose was ingested at the end of an experiment in low oxygen, while the subject remained dark adapted, the effects of the anoxia were largely counteracted within 6 to 8 minutes. 4. The influence of low blood sugar on light sensitivity was then studied by injecting insulin. The thresholds were raised as soon as the effects of the insulin produced a fall in the blood sugar. When the subjects inhaled oxygen the thresholds were lowered. Then when the oxygen was withdrawn so that the subject was breathing normal air, the thresholds rose again within 1 to 2 minutes. Finally, if the blood sugar was raised by ingesting glucose, the average threshold fell to the original control level or even below it. 5. The combined effects of low oxygen and low blood sugar on light sensitivity were studied in one subject (W. F.). These effects appeared to be greater than when a similar degree of anoxia or hypoglycemia was brought about separately. 6. In a series of experiments on ten subjects the dark adaptation curves were obtained both in the basal state and after a normal breakfast. In nine of the ten subjects, the food increased the sensitivity of the subjects to light. 7. The experiments reported above lend support to the hypothesis that both anoxia and hypoglycemia produce their effects on light sensitivity in essentially the same way; namely, by slowing the oxidative processes. Consequently the effects of anoxia may be ameliorated by giving glucose and the effects of hypoglycemia by inhaling oxygen. In our opinion, the changes may be attributed directly to the effects on the nervous tissue of the visual mechanism and the brain rather than on the photochemical processes of the retina. PMID:19873200

Statistical Frequency-Dependent Analysis of Trial-to-Trial Variability in Single Time Series by Recurrence Plots.

PubMed

Tošić, Tamara; Sellers, Kristin K; Fröhlich, Flavio; Fedotenkova, Mariia; Beim Graben, Peter; Hutt, Axel

2015-01-01

For decades, research in neuroscience has supported the hypothesis that brain dynamics exhibits recurrent metastable states connected by transients, which together encode fundamental neural information processing. To understand the system's dynamics it is important to detect such recurrence domains, but it is challenging to extract them from experimental neuroscience datasets due to the large trial-to-trial variability. The proposed methodology extracts recurrent metastable states in univariate time series by transforming datasets into their time-frequency representations and computing recurrence plots based on instantaneous spectral power values in various frequency bands. Additionally, a new statistical inference analysis compares different trial recurrence plots with corresponding surrogates to obtain statistically significant recurrent structures. This combination of methods is validated by applying it to two artificial datasets. In a final study of visually-evoked Local Field Potentials in partially anesthetized ferrets, the methodology is able to reveal recurrence structures of neural responses with trial-to-trial variability. Focusing on different frequency bands, the δ-band activity is much less recurrent than α-band activity. Moreover, α-activity is susceptible to pre-stimuli, while δ-activity is much less sensitive to pre-stimuli. This difference in recurrence structures in different frequency bands indicates diverse underlying information processing steps in the brain.

Statistical Frequency-Dependent Analysis of Trial-to-Trial Variability in Single Time Series by Recurrence Plots

PubMed Central

Tošić, Tamara; Sellers, Kristin K.; Fröhlich, Flavio; Fedotenkova, Mariia; beim Graben, Peter; Hutt, Axel

2016-01-01

For decades, research in neuroscience has supported the hypothesis that brain dynamics exhibits recurrent metastable states connected by transients, which together encode fundamental neural information processing. To understand the system's dynamics it is important to detect such recurrence domains, but it is challenging to extract them from experimental neuroscience datasets due to the large trial-to-trial variability. The proposed methodology extracts recurrent metastable states in univariate time series by transforming datasets into their time-frequency representations and computing recurrence plots based on instantaneous spectral power values in various frequency bands. Additionally, a new statistical inference analysis compares different trial recurrence plots with corresponding surrogates to obtain statistically significant recurrent structures. This combination of methods is validated by applying it to two artificial datasets. In a final study of visually-evoked Local Field Potentials in partially anesthetized ferrets, the methodology is able to reveal recurrence structures of neural responses with trial-to-trial variability. Focusing on different frequency bands, the δ-band activity is much less recurrent than α-band activity. Moreover, α-activity is susceptible to pre-stimuli, while δ-activity is much less sensitive to pre-stimuli. This difference in recurrence structures in different frequency bands indicates diverse underlying information processing steps in the brain. PMID:26834580

Geologic map of the Riverside East 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Cox, Brett F.

2001-01-01

a. This Readme; includes in Appendix I, data contained in rse_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Geologic map of the Corona North 7.5' quadrangle, Riverside and San Bernardino counties, California

USGS Publications Warehouse

Morton, Douglas M.; Gray, C.H.; Bovard, Kelly R.; Dawson, Michael

2002-01-01

a. This Readme; includes in Appendix I, data contained in crn_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced precise 1:24,000- scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Geologic map of the Corona South 7.5' quadrangle, Riverside and Orange counties, California

USGS Publications Warehouse

Gray, C.H.; Morton, Douglas M.; Weber, F. Harold; Digital preparation by Bovard, Kelly R.; O'Brien, Timothy

2002-01-01

a. A Readme file; includes in Appendix I, data contained in crs_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Geologic map of the Lake Mathews 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Weber, F. Harold

2001-01-01

a. This Readme; includes in Appendix I, data contained in lkm_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Miscellaneous Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous.Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand.In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Geologic map of the Steele Peak 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; digital preparation by Alvarez, Rachel M.; Diep, Van M.

2001-01-01

a. This Readme; includes in Appendix I, data contained in stp_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Geologic map of the Riverside West 7.5' quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Cox, Brett F.

2001-01-01

a. This Readme; includes in Appendix I, data contained in rsw_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Marine deposits are in part overlain by local, mostly alluvial fan, deposits and are labeled Qomf. Grain size follows f.Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Venous return curves obtained from graded series of valsalva maneuvers

NASA Technical Reports Server (NTRS)

Mastenbrook, S. M., Jr.

1974-01-01

The effects were studied of a graded series of valsalva-like maneuvers on the venous return, which was measured transcutaneously in the jugular vein of an anesthetized dog, with the animal serving as its own control. At each of five different levels of central venous pressure, the airway pressure which just stopped venous return during each series of maneuvers was determined. It was found that this end-point airway pressure is not a good estimator of the animal's resting central venous pressure prior to the simulated valsalva maneuver. It was further found that the measured change in right atrial pressure during a valsalva maneuver is less than the change in airway pressure during the same maneuver, instead of being equal, as had been expected. Relative venous return curves were constructed from the data obtained during the graded series of valsalva maneuvers.

Characterization of water retention curves for a series of cultivated histosols

Treesearch

Dennis W. Hallema; Yann Périard; Jonathan A. Lafond; Silvio J. Gumiere; Jean Caron

2015-01-01

Water retention curves are essential for the parameterization of soil water models such as HYDRUS. Although hydraulic parameters are known for a large number of mineral and natural organic soils, our knowledge on the hydraulic behavior of cultivated Histosols is rather limited. The objective of this study was to derive characteristic water retention curves for a large...

Relative loading on biplane wings

NASA Technical Reports Server (NTRS)

Diehl, Walter S

1934-01-01

Recent improvements in stress analysis methods have made it necessary to revise and to extend the loading curves to cover all conditions of flight. This report is concerned with a study of existing biplane data by combining the experimental and theoretical data to derive a series of curves from which the lift curves of the individual wings of a biplane may be obtained.

A Simple yet Accurate Method for Students to Determine Asteroid Rotation Periods from Fragmented Light Curve Data

ERIC Educational Resources Information Center

Beare, R. A.

2008-01-01

Professional astronomers use specialized software not normally available to students to determine the rotation periods of asteroids from fragmented light curve data. This paper describes a simple yet accurate method based on Microsoft Excel[R] that enables students to find periods in asteroid light curve and other discontinuous time series data of…

Data user's notes of the radio astronomy experiment aboard the OGO-V spacecraft

NASA Technical Reports Server (NTRS)

Haddock, F. T.; Breckenridge, S. L.

1970-01-01

General information concerning the low-frequency radiometer, instrument package launching and operation, and scientific objectives of the flight are provided. Calibration curves and correction factors, with general and detailed information on the preflight calibration procedure are included. The data acquisition methods and the format of the data reduction, both on 35 mm film and on incremental computer plots, are described.

Rotational Analysis of Phase Plane Curves: Complex and Pure Imaginary Eigenvalues

ERIC Educational Resources Information Center

Murray, Russell H.

2005-01-01

Although the phase plane can be plotted and analyzed using an appropriate software package, the author found it worthwhile to engage the students with the theorem and the two proofs. The theorem is a powerful tool that provides insight into the rotational behavior of the phase plane diagram in a simple way: just check the signs of c and [alpha].…

Reliability Factors for Electronic Components in a Storage Environment

DTIC Science & Technology

1977-09-01

Other moisture-induced failure mechanisms include crack propagation in brittle materials such as ceramic seals, glass passivation layers, nitride ...for Aluminum -Gold .... .............. ... 80 4-5 Fatigue S-N Curve Typical for Most Metals and Polymers . 85 4-6 Comparison of Surface Damageý Within...8 Aluminum -Silicon Phase Diagram ...... ............... 96 5-1 Evaluation of Gases from Microcircuit Package .... ....... 121 6-1 Plot of Resistivity

Physical studies of small asteroids. I - Lightcurves and taxonomy of 10 asteroids

NASA Technical Reports Server (NTRS)

Wisniewski, W. Z.

1991-01-01

Photometric observations of 10 small asteroids (10 km or less in diameter), obtained using the 1.5-m Mt. Lemmon and 2.3-m Kitt Peak telescopes of the University of Arizona during 1986-1987, are reported. The instrumentation and data-reduction techniques employed are described, and the results are presented in tables and light-curve plots and briefly characterized.

TSSGNEO suggestions for refinement of safety criteria for dam at the Sayano-Shushenskaya HPP

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

Savich, A. I.; Gaziev, E. G.

2013-09-15

Analysis of radial-displacements of the dam, measured by direct and inverted plumb lines, indicates that curves of the variation in radial displacements of the dam at different elevations make it possible to plot diagrams of increases in the radial displacement over the entire height of the dam, i.e., inclines of the axis of the dam to the vertical.

The Low Temperature Chamber Testing of the Compression Ignition Engine and System of the Armoured Personnel Carrier (APC) M113A1.

DTIC Science & Technology

1981-06-01

shutdown. Before start up the hot oil would be pumped ( auxillary pump) back through the engine on the high pressure side of the engine’ s oil pump. This...insulation heating was applied. Temperature plots Figure 14* to Figure 16* show the battery cooling curves for auxillary heating when 37mm of medium

Nonlinear model identification and spectral submanifolds for multi-degree-of-freedom mechanical vibrations

NASA Astrophysics Data System (ADS)

Szalai, Robert; Ehrhardt, David; Haller, George

2017-06-01

In a nonlinear oscillatory system, spectral submanifolds (SSMs) are the smoothest invariant manifolds tangent to linear modal subspaces of an equilibrium. Amplitude-frequency plots of the dynamics on SSMs provide the classic backbone curves sought in experimental nonlinear model identification. We develop here, a methodology to compute analytically both the shape of SSMs and their corresponding backbone curves from a data-assimilating model fitted to experimental vibration signals. This model identification utilizes Taken's delay-embedding theorem, as well as a least square fit to the Taylor expansion of the sampling map associated with that embedding. The SSMs are then constructed for the sampling map using the parametrization method for invariant manifolds, which assumes that the manifold is an embedding of, rather than a graph over, a spectral subspace. Using examples of both synthetic and real experimental data, we demonstrate that this approach reproduces backbone curves with high accuracy.

Green leaf phenology at Landsat resolution: scaling from the plot to satellite

NASA Astrophysics Data System (ADS)

Fisher, J. I.; Mustard, J. F.; Vadeboncour, M.

2005-12-01

Despite the large number of in situ, plot-level phenological measurements and satellite-derived phenological studies, there has been little success to date in merging these records temporally or spatially. In particular, while most phenological patterns and trends derived from satellites appear realistic and coherent, they may not reflect spatial and temporal patterns at the plot level. An obvious explanation is the drastic scale difference from plot-level to most satellite observations. In this research, we bridge this scale gap through higher resolution satellite records (Landsat) and quantify the accuracy of satellite-derived metrics with direct field measurements. We compiled fifty-seven Landsat scenes from southern New England (P12 R51) from 1984 to 2002. Green vegetation areal abundance for each scene was derived from spectral mixture analysis and a single set of endmembers. The leaf area signal was fit with a logistic-growth simulating sigmoid curve to derive phenological markers (half-maximum leaf-onset and offset). Spring leaf-onset dates in homogenous stands of deciduous forests displayed significant and persistent local variability. The local variability was validated with multiple springtime ground observations (r2 = 0.91). The highest degree of verified small-scale variation occurred where contiguous forests displayed leaf-onset gradients of 10-14 days over short distances (<500 m). These dramatic gradients, of a similar magnitude to differences in leaf-onset from MD to MA, occur in of low-relief (<40 m) upland regions. The patterns suggest that microclimates resulting from springtime cold-air drainage may be influential in governing the start of leaf growth. These microclimates may be of crucial importance in interpreting in situ records and interpolating phenology from satellite data. Regional patterns from the Landsat analyses suggest topographic, coastal, and land-use controls on phenology. For example, our results indicate that deciduous forests in the Providence, RI metropolitan area leaf out 5-7 days earlier than comparable rural areas. In preliminary work, we validated the Landsat-derived metrics with similar analyses of MODIS and AVHRR, and demonstrate that aggregating diverse local phenologies into coarse grids may convolute interpretations. Despite these complications, the platform-independent curve-fit methodology may be extended across platforms and field data. The methodologically consistent approach, in tandem with Landsat data, allows us to effectively scale between plot and satellite phenological observations.

Rational-Spline Subroutines

NASA Technical Reports Server (NTRS)

Schiess, James R.; Kerr, Patricia A.; Smith, Olivia C.

1988-01-01

Smooth curves drawn among plotted data easily. Rational-Spline Approximation with Automatic Tension Adjustment algorithm leads to flexible, smooth representation of experimental data. "Tension" denotes mathematical analog of mechanical tension in spline or other mechanical curve-fitting tool, and "spline" as denotes mathematical generalization of tool. Program differs from usual spline under tension, allows user to specify different values of tension between adjacent pairs of knots rather than constant tension over entire range of data. Subroutines use automatic adjustment scheme that varies tension parameter for each interval until maximum deviation of spline from line joining knots less than or equal to amount specified by user. Procedure frees user from drudgery of adjusting individual tension parameters while still giving control over local behavior of spline.

Photometry of AM Herculis - A slow optical pulsar

NASA Technical Reports Server (NTRS)

Priedhorsky, W. C.; Krzeminski, W.

1978-01-01

Multicolor photometry of the X-ray binary AM Her suggests that the red component of the optical flux is closely related to the source of optical circular polarization in the system. It is concluded from the periodic modulation of flux in the U through R bands, which is particularly well-defined when plotted as color curves, that the primary and secondary minima are neither eclipses by a secondary star nor eclipses by a hot spot. It is suggested that the primary minimum in the visual light curve is the eclipse of a region of intense optical emission in the magnetic field near the surface of a degenerate dwarf by that dwarf itself.

The Chern-Simons Current in Systems of DNA-RNA Transcriptions

NASA Astrophysics Data System (ADS)

Capozziello, Salvatore; Pincak, Richard; Kanjamapornkul, Kabin; Saridakis, Emmanuel N.

2018-04-01

A Chern-Simons current, coming from ghost and anti-ghost fields of supersymmetry theory, can be used to define a spectrum of gene expression in new time series data where a spinor field, as alternative representation of a gene, is adopted instead of using the standard alphabet sequence of bases $A, T, C, G, U$. After a general discussion on the use of supersymmetry in biological systems, we give examples of the use of supersymmetry for living organism, discuss the codon and anti-codon ghost fields and develop an algebraic construction for the trash DNA, the DNA area which does not seem active in biological systems. As a general result, all hidden states of codon can be computed by Chern-Simons 3 forms. Finally, we plot a time series of genetic variations of viral glycoprotein gene and host T-cell receptor gene by using a gene tensor correlation network related to the Chern-Simons current. An empirical analysis of genetic shift, in host cell receptor genes with separated cluster of gene and genetic drift in viral gene, is obtained by using a tensor correlation plot over time series data derived as the empirical mode decomposition of Chern-Simons current.

Guide to Using Onionskin Analysis Code (U)

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

Fugate, Michael Lynn; Morzinski, Jerome Arthur

2016-09-15

This document is a guide to using R-code written for the purpose of analyzing onionskin experiments. We expect the user to be very familiar with statistical methods and the R programming language. For more details about onionskin experiments and the statistical methods mentioned in this document see Storlie, Fugate, et al. (2013). Engineers at LANL experiment with detonators and high explosives to assess performance. The experimental unit, called an onionskin, is a hemisphere consisting of a detonator and a booster pellet surrounded by explosive material. When the detonator explodes, a streak camera mounted above the pole of the hemisphere recordsmore » when the shock wave arrives at the surface. The output from the camera is a two-dimensional image that is transformed into a curve that shows the arrival time as a function of polar angle. The statistical challenge is to characterize a baseline population of arrival time curves and to compare the baseline curves to curves from a new, so-called, test series. The hope is that the new test series of curves is statistically similar to the baseline population.« less

THE USE OF QUENCHING IN A LIQUID SCINTILLATION COUNTER FOR QUANTITATIVE ANALYSIS

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

Foster, G.V.

1963-01-01

Quenching was used to quantitatively determine the amonnt of quenching agent present. A sealed promethium147 source was prepared to be used for the count rate determinations. Two methods to determine the amount of quenching agent present in a sample were developed. One method related the count rate of a sample containing a quenching agent to the amount of quenching agent present. Calibration curves were plotted using both color and chemical quenchers. The quenching agents used were: F.D.C. Orange No. 2, F.D.C. Yellow No. 3, F.D.C. Yellow No. 4, Scarlet Red, acetone, benzaldehyde, and carbon tetrachloride. the color quenchers gave amore » linear-relationship, while the chemical quenchers gave a non-linear relationship. Quantities of the color quenchers between about 0.008 mg and 0.100 mg can be determined with an error less than 5%. The calibration curves were found to be usable over a long period of time. The other method related the change in the ratio of the count rates in two voltage windows to the amount of quenching agent present. The quenchers mentioned above were used. Calibration curves were plotted for both the color and chemical quenchers. The relationships of ratio versus amount of quencher were non-linear in each case. It was shown that the reproducibility of the count rate and the ratio was independent of the amount of quencher present but was dependent on the count rate. At count rates above 10,000 counts per minute the reproducibility was better than 1%. (TCO)« less

Vortex-glass state in the isovalent optimally doped pnictide superconductor BaFe2(As0.68P0.32)2

NASA Astrophysics Data System (ADS)

Salem-Sugui, S., Jr.; Mosqueira, J.; Alvarenga, A. D.; Sóñora, D.; Crisan, A.; Ionescu, A. M.; Sundar, S.; Hu, D.; Li, S.-L.; Luo, H.-Q.

2017-05-01

We report on isochamp magneto-resistivity and ac susceptibility curves obtained in a high-quality single crystal of the isovalent optimally doped pnictide BaFe2(As{}0.68P{}0.32)2 with superconducting temperature T c = 27.8 K for H∥c-axis. Plots of the logarithmic derivative of the resistivity curves allowed the identification of a vortex-glass (VG) phase and to obtain the values of the critical glass temperature T g, the temperature T * marking the transition to the liquid phase and of the critical exponent s. The presence of the VG phase is confirmed by detailed measurements of the third harmonic signal of the ac magnetic susceptibility. The modified VG model was successfully applied to the data allowing the obtention of the temperature independent VG activation energy U b . The activation energy U 0 obtained from the Arrhenius plots in the flux-flow region are compared with U b and with U 0 obtained from flux-creep measurements on a M(H) isothermal in the same sample. A phase diagram of the studied sample is constructed showing the T g glass line, the T * line representing a transition (melting) to the liquid phase, the mean field temperature T c(H) line and the H p line obtained from the peaks in isothermal critical current, J c(H) curves, which are explained in terms of a softening of the vortex lattice. The glass line was fitted by a theory presented in the literature which considers the effect of disorder.

High-resolution mapping of yield curve shape and evolution for high porosity sandstones

NASA Astrophysics Data System (ADS)

Bedford, J. D.; Faulkner, D.; Wheeler, J.; Leclere, H.

2017-12-01

The onset of permanent inelastic deformation for porous rock is typically defined by a yield curve plotted in P-Q space, where P is the effective mean stress and Q is the differential stress. Sandstones usually have broadly elliptical shaped yield curves, with the low pressure side of the ellipse associated with localized brittle faulting (dilation) and the high pressure side with distributed ductile deformation (compaction). However recent works have shown that these curves might not be perfectly elliptical and that significant evolution in shape occurs with continued deformation. We therefore use a novel stress-probing methodology to map in high-resolution the yield curve shape for Boise and Idaho Gray sandstones (36-38% porosity) and also investigate curve evolution with increasing deformation. The data reveal yield curves with a much flatter geometry than previously recorded for porous sandstone and that the compactive side of the curve is partly comprised of a near vertical limb. The yield curve evolution is found to be strongly dependent on the nature of inelastic strain. Samples that were compacted under a deviatoric load, with a component of inelastic shear strain, were found to have yield curves with peaks that are approximately 50% higher than similar porosity samples that were hydrostatically compacted (i.e. purely volumetric strain). The difference in yield curve evolution along the different loading paths is attributed to mechanical anisotropy that develops during deviatoric loading by the closure of preferentially orientated fractures. Increased shear strain also leads to the formation of a plateau at the peak of the yield curve as samples deform along the deviatoric loading path. These results have important implications for understanding how the strength of porous rock evolves along different stress paths, including during fluid extraction from hydrocarbon reservoirs where the stress state is rarely isotropic.

Reducing sojourn points from recurrence plots to improve transition detection: Application to fetal heart rate transitions.

PubMed

Zaylaa, Amira; Charara, Jamal; Girault, Jean-Marc

2015-08-01

The analysis of biomedical signals demonstrating complexity through recurrence plots is challenging. Quantification of recurrences is often biased by sojourn points that hide dynamic transitions. To overcome this problem, time series have previously been embedded at high dimensions. However, no one has quantified the elimination of sojourn points and rate of detection, nor the enhancement of transition detection has been investigated. This paper reports our on-going efforts to improve the detection of dynamic transitions from logistic maps and fetal hearts by reducing sojourn points. Three signal-based recurrence plots were developed, i.e. embedded with specific settings, derivative-based and m-time pattern. Determinism, cross-determinism and percentage of reduced sojourn points were computed to detect transitions. For logistic maps, an increase of 50% and 34.3% in sensitivity of detection over alternatives was achieved by m-time pattern and embedded recurrence plots with specific settings, respectively, and with a 100% specificity. For fetal heart rates, embedded recurrence plots with specific settings provided the best performance, followed by derivative-based recurrence plot, then unembedded recurrence plot using the determinism parameter. The relative errors between healthy and distressed fetuses were 153%, 95% and 91%. More than 50% of sojourn points were eliminated, allowing better detection of heart transitions triggered by gaseous exchange factors. This could be significant in improving the diagnosis of fetal state. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preliminary geologic map of the Elsinore 7.5' Quadrangle, Riverside County, California

USGS Publications Warehouse

Morton, Douglas M.; Weber, F. Harold; Digital preparation: Alvarez, Rachel M.; Burns, Diane

2003-01-01

Open-File Report 03-281 contains a digital geologic map database of the Elsinore 7.5’ quadrangle, Riverside County, California that includes: 1. ARC/INFO (Environmental Systems Research Institute, http://www.esri.com) version 7.2.1 coverages of the various elements of the geologic map. 2. A Postscript file to plot the geologic map on a topographic base, and containing a Correlation of Map Units diagram (CMU), a Description of Map Units (DMU), and an index map. 3. Portable Document Format (.pdf) files of: a. This Readme; includes in Appendix I, data contained in els_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced precise 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

Does the Budyko curve reflect a maximum power state of hydrological systems? A backward analysis

NASA Astrophysics Data System (ADS)

Westhoff, Martijn; Zehe, Erwin; Archambeau, Pierre; Dewals, Benjamin

2016-04-01

Almost all catchments plot within a small envelope around the Budyko curve. This apparent behaviour suggests that organizing principles may play a role in the evolution of catchments. In this paper we applied the thermodynamic principle of maximum power as the organizing principle. In a top-down approach we derived mathematical formulations of the relation between relative wetness and gradients driving runoff and evaporation for a simple one-box model. We did this in an inverse manner such that when the conductances are optimized with the maximum power principle, the steady state behaviour of the model leads exactly to a point on the asymptotes of the Budyko curve. Subsequently, we added dynamics in forcing and actual evaporations, causing the Budyko curve to deviate from the asymptotes. Despite the simplicity of the model, catchment observations compare reasonably well with the Budyko curves subject to observed dynamics in rainfall and actual evaporation. Thus by constraining the - with the maximum power principle optimized - model with the asymptotes of the Budyko curve we were able to derive more realistic values of the aridity and evaporation index without any parameter calibration. Future work should focus on better representing the boundary conditions of real catchments and eventually adding more complexity to the model.

Does the Budyko curve reflect a maximum-power state of hydrological systems? A backward analysis

NASA Astrophysics Data System (ADS)

Westhoff, M.; Zehe, E.; Archambeau, P.; Dewals, B.

2016-01-01

Almost all catchments plot within a small envelope around the Budyko curve. This apparent behaviour suggests that organizing principles may play a role in the evolution of catchments. In this paper we applied the thermodynamic principle of maximum power as the organizing principle. In a top-down approach we derived mathematical formulations of the relation between relative wetness and gradients driving run-off and evaporation for a simple one-box model. We did this in an inverse manner such that, when the conductances are optimized with the maximum-power principle, the steady-state behaviour of the model leads exactly to a point on the asymptotes of the Budyko curve. Subsequently, we added dynamics in forcing and actual evaporation, causing the Budyko curve to deviate from the asymptotes. Despite the simplicity of the model, catchment observations compare reasonably well with the Budyko curves subject to observed dynamics in rainfall and actual evaporation. Thus by constraining the model that has been optimized with the maximum-power principle with the asymptotes of the Budyko curve, we were able to derive more realistic values of the aridity and evaporation index without any parameter calibration. Future work should focus on better representing the boundary conditions of real catchments and eventually adding more complexity to the model.

Does the Budyko curve reflect a maximum power state of hydrological systems? A backward analysis

NASA Astrophysics Data System (ADS)

Westhoff, M.; Zehe, E.; Archambeau, P.; Dewals, B.

2015-08-01

Almost all catchments plot within a small envelope around the Budyko curve. This apparent behaviour suggests that organizing principles may play a role in the evolution of catchments. In this paper we applied the thermodynamic principle of maximum power as the organizing principle. In a top-down approach we derived mathematical formulations of the relation between relative wetness and gradients driving runoff and evaporation for a simple one-box model. We did this in such a way that when the conductances are optimized with the maximum power principle, the steady state behaviour of the model leads exactly to a point on the Budyko curve. Subsequently we derived gradients that, under constant forcing, resulted in a Budyko curve following the asymptotes closely. With these gradients we explored the sensitivity of dry spells and dynamics in actual evaporation. Despite the simplicity of the model, catchment observations compare reasonably well with the Budyko curves derived with dynamics in rainfall and evaporation. This indicates that the maximum power principle may be used (i) to derive the Budyko curve and (ii) to move away from the empiricism in free parameters present in many Budyko functions. Future work should focus on better representing the boundary conditions of real catchments and eventually adding more complexity to the model.

Theoretical Studies of Strongly Interacting Fine Particle Systems

NASA Astrophysics Data System (ADS)

Fearon, Michael

Available from UMI in association with The British Library. A theoretical analysis of the time dependent behaviour of a system of fine magnetic particles as a function of applied field and temperature was carried out. The model used was based on a theory assuming Neel relaxation with a distribution of particle sizes. This theory predicted a linear variation of S_{max} with temperature and a finite intercept, which is not reflected by experimental observations. The remanence curves of strongly interacting fine-particle systems were also investigated theoretically. It was shown that the Henkel plot of the dc demagnetisation remanence vs the isothermal remanence is a useful representation of interactions. The form of the plot was found to be a reflection of the magnetic and physical microstructure of the material, which is consistent with experimental data. The relationship between the Henkel plot and the noise of a particulate recording medium, another property dependent on the microstructure, is also considered. The Interaction Field Factor (IFF), a single parameter characterising the non-linearity of the Henkel plot, is investigated. These results are consistent with a previous experimental study. Finally the results of the noise power spectral density for erased and saturated recording media are presented, so that characterisation of interparticle interactions may be carried out with greater accuracy.

UAV remote sening for precision agriculture

NASA Astrophysics Data System (ADS)

Vigneau, Nathalie; Chéron, Corentin; Mainfroy, Florent; Faroux, Romain

2014-05-01

Airinov offers to farmers, scientists and experimenters (plant breeders, etc.) its technical skills about UAVs, cartography and agronomic remote sensing. The UAV is a 2-m-wingspan flying wing. It can carry away either a RGB camera or a multispectral sensor, which records reflectance in 4 spectral bands. The spectral characteristics of the sensor are modular. Each spectral band is comprised between 400 and 850 nm and the FWHM (Full Width at Half Maximum) is between 10 and 40 nm. The spatial resolution varies according to sensor, flying height and user needs from 15cm/px for multispectral sensor at 150m to 1.5cm/px for RGB camera at 50m. The flight is totally automatic thanks to on-board autopilot, IMU (Inertial Measurement Unit) and GPS. Data processing (unvignetting, mosaicking, correction in reflectance) leads to agronomic variables as LAI (Leaf Area Index) or chlorophyll content for barley, wheat, rape and maize as well as vegetation indices as NDVI (Normalized Difference Vegetation Index). Using these data, Airinov can product advices for farmers as nitrogen preconisation for rape. For scientists, Airinov offers trial plot monitoring by micro-plots vectorisation and numerical data exctraction micro-plot by micro-plot. This can lead to kinetic curve for LAI or NDVI to compare cover establishment for different genotypes for example. Airinov's system is a new way to monitor plots with a lot of data (biophysical or biochemical parameters) at high rate, high spatial resolution and high precision.

Development of technique for air coating and nickel and copper metalization of solar cells

NASA Technical Reports Server (NTRS)

1982-01-01

Solar cells were made with a variety of base metal screen printing inks applied over silicon nitride AR coating and copper electroplated. Fritted and fritless nickel and fritless tin base printing inks were evaluated. Conversion efficiencies as high as 9% were observed with fritted nickel ink contacts, however, curve shapes were generally poor, reflecting high series resistance. Problems encountered in addition to high series reistance included loss of adhesion of the nickel contacts during plating and poor adhesion, oxidation and inferior curve shapes with the tin base contacts.

QUICK - AN INTERACTIVE SOFTWARE ENVIRONMENT FOR ENGINEERING DESIGN

NASA Technical Reports Server (NTRS)

Schlaifer, R. S.

1994-01-01

QUICK provides the computer user with the facilities of a sophisticated desk calculator which can perform scalar, vector and matrix arithmetic, propagate conic orbits, determine planetary and satellite coordinates and perform other related astrodynamic calculations within a Fortran-like environment. QUICK is an interpreter, therefore eliminating the need to use a compiler or a linker to run QUICK code. QUICK capabilities include options for automated printing of results, the ability to submit operating system commands on some systems, and access to a plotting package (MASL)and a text editor without leaving QUICK. Mathematical and programming features of QUICK include the ability to handle arbitrary algebraic expressions, the capability to define user functions in terms of other functions, built-in constants such as pi, direct access to useful COMMON areas, matrix capabilities, extensive use of double precision calculations, and the ability to automatically load user functions from a standard library. The MASL (The Multi-mission Analysis Software Library) plotting package, included in the QUICK package, is a set of FORTRAN 77 compatible subroutines designed to facilitate the plotting of engineering data by allowing programmers to write plotting device independent applications. Its universality lies in the number of plotting devices it puts at the user's disposal. The MASL package of routines has proved very useful and easy to work with, yielding good plots for most new users on the first or second try. The functions provided include routines for creating histograms, "wire mesh" surface plots and contour plots as well as normal graphs with a large variety of axis types. The library has routines for plotting on cartesian, polar, log, mercator, cyclic, calendar, and stereographic axes, and for performing automatic or explicit scaling. The lengths of the axes of a plot are completely under the control of the program using the library. Programs written to use the MASL subroutines can be made to output to the Calcomp 1055 plotter, the Hewlett-Packard 2648 graphics terminal, the HP 7221, 7475 and 7550 pen plotters, the Tektronix 40xx and 41xx series graphics terminals, the DEC VT125/VT240 graphics terminals, the QMS 800 laser printer, the Sun Microsystems monochrome display, the Ridge Computers monochrome display, the IBM/PC color display, or a "dumb" terminal or printer. Programs using this library can be written so that they always use the same type of plotter or they can allow the choice of plotter type to be deferred until after program execution. QUICK is written in RATFOR for use on Sun4 series computers running SunOS. No source code is provided. The standard distribution medium for this program is a .25 inch streaming magnetic tape cartridge in UNIX tar format. An electronic copy of the documentation in ASCII format is included on the distribution medium. QUICK was developed in 1991 and is a copyrighted work with all copyright vested in NASA.

Tides, and tidal and residual currents in Suisun and San Pablo bays, California; results of measurements, 1986

USGS Publications Warehouse

Gartner, J.W.; Yost, B.T.

1988-01-01

Current meter data collected at 11 stations and water level data collected at one station in Suisun and San Pablo Bays, California, in 1986 are compiled in this report. Current-meter measurements include current speed and direction, and water temperature and salinity (computed from temperature and conductivity). For each of the 19 current-meter records, data are presented in two forms. These are: (1) results of harmonic analysis; and (2) plots of tidal current speed and direction versus time and plots of temperature and salinity versus time. Spatial distribution of the properties of tidal currents are given in graphic form. In addition, Eulerian residual currents have been compiled by using a vector-averaging technique. Water level data are presented in the form of a time-series plot and the results of harmonic analysis. (USGS)

WASP (Write a Scientific Paper) using Excel - 3: Plotting data.

PubMed

Grech, Victor

2018-02-01

The plotting of data into graphs should be a mandatory step in all data analysis as part of a descriptive statistics exercise, since it gives the researcher an overview of the shape and nature of the data. Moreover, outlier values may be identified, which may be incorrect data, or true outliers, from which important findings (and publications) may arise. This exercise should always precede inferential statistics, when possible, and this paper in the Early Human Development WASP series provides some pointers for doing so in Microsoft Excel™. Copyright © 2018 Elsevier B.V. All rights reserved.

FATS: Feature Analysis for Time Series

NASA Astrophysics Data System (ADS)

Nun, Isadora; Protopapas, Pavlos; Sim, Brandon; Zhu, Ming; Dave, Rahul; Castro, Nicolas; Pichara, Karim

2017-11-01

FATS facilitates and standardizes feature extraction for time series data; it quickly and efficiently calculates a compilation of many existing light curve features. Users can characterize or analyze an astronomical photometric database, though this library is not necessarily restricted to the astronomical domain and can also be applied to any kind of time series data.

[Hemodynamic variability caused by pressure-volume plotting and alveolar recruitment maneuvers in patients with adult respiratory distress syndrome].

PubMed

Pestaña, D; Royo, C; Hernández-Gancedo, C; Martínez-Casanova, E; Criado, A

2008-01-01

The plotting of pressure-volume curves and the performance of alveolar recruitment maneuvers are common practices in the care of patients with adult respiratory distress syndrome (ARDS), even though potentially harmful hemodynamic effects are associated with sustaining a high intrathoracic pressure. Our aim was to analyze hemodynamic and ventilatory changes related to these 2 maneuvers and to assess the short-term effectiveness of recruitment. The patients had ARDS and were being monitored with a catheter connected to a PiCCO system. All measurements were taken in sinus rhythm and with adequate vascular filling. Values recorded during plotting of the quasistatic pressure-volume curve and the recruitment maneuver (sustained airway pressure of 40 cm H2O) were the cardiac index, mean arterial pressure, heart rate, systolic volume index, and oxygen saturation (SpO2). Blood gas measurements were recorded before the maneuvers and 15 minutes afterwards. All parameters decreased significantly in the 14 patients studied. The mean (SD) maximum decreases, from which all patients recovered within 2 minutes, were as follows: cardiac index, 26% (16%); mean arterial pressure, 6% (6%); heart rate, 4% (5%), systolic volume index, 21% (15%); and SpO2, 3% (3%). Significant increases in PaO2 (7% [6%]) and the ratio of PaO2 to the fraction of inspired oxygen were recorded after the recruitment maneuver (P=.016 and P=.014, respectively), but the changes were not clinically significant. The hemodynamic disturbances associated with the alveolar recruitment maneuver based on sustaining a high end-expiratory pressure and the minor improvement in oxygenation achieved as a result suggest that the routine use of that maneuver in ARDS patients is of questionable value.

The MRI-measured arterial input function resulting from a bolus injection of Gd-DTPA in a rat model of stroke slightly underestimates that of Gd-[14C]DTPA and marginally overestimates the blood-to-brain influx rate constant determined by Patlak plots

PubMed Central

Nagaraja, Tavarekere N.; Karki, Kishor; Ewing, James R.; Divine, George W.; Fenstermacher, Joseph D.; Patlak, Clifford S.; Knight, Robert A.

2009-01-01

The hypothesis that the arterial input function (AIF) of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) injected by intravenous (iv) bolus and measured by the change in the T1-relaxation rate (ΔR1; R1=1/T1) of superior sagittal sinus blood (AIF-I) approximates the AIF of 14C-labeled Gd-DTPA measured in arterial blood (AIF*) was tested in a rat stroke model (n=13). Contrary to the hypothesis, the initial part of the ΔR1-time curve was underestimated, and the area under the normalized curve for AIF-I was about 15% lower than that for AIF*, the reference AIF. Hypothetical AIF’s for Gd-DTPA (AIF-II) were derived from the AIF* values and averaged to obtain AIF-III. Influx rate constants (Ki) and proton distribution volumes at zero time (Vp+Vo) were estimated with Patlak plots of AIF-I, -II and -III and tissue ΔR1 data. For the regions of interest, the Ki’s estimated with AIF-I were slightly but not significantly higher than those obtained with AIF-II and AIF-III. In contrast, Vp+Vo was significantly higher when calculated with AIF-I. Similar estimates of Ki and Vp+Vo were obtained with AIF-II and AIF-III. In summary, AIF-I underestimated the reference AIF (AIF*); this shortcoming had little effect on the Ki calculated by Patlak plot but produced a significant overestimation of Vp+Vo. PMID:20512853

Microcumpter computation of water quality discharges

USGS Publications Warehouse

Helsel, Dennis R.

1983-01-01

A fully prompted program (SEDQ) has been developed to calculate daily and instantaneous water quality (QW) discharges. It is written in a version of BASIC, and requires inputs of gage heights, discharge rating curve, shifts, and water quality concentration information. Concentration plots may be modified interactively using the display screen. Semi-logarithmic plots of concentration and water quality discharge are output to the display screen, and optionally to plotters. A summary table of data is also output. SEDQ could be a model program for micro and minicomputer systems likely to be in use within the Water Resources Division, USGS, in the near future. The daily discharge-weighted mean concentration is one output from SEDQ. It is defined in this report, differentiated from the currently used mean concentration, and designated the ' equivalent concentration. ' (USGS)

Interactions between silica particles in the presence of multivalent coions.

PubMed

Uzelac, Biljana; Valmacco, Valentina; Trefalt, Gregor

2017-08-30

Forces between charged silica particles in solutions of multivalent coions are measured with colloidal probe technique based on atomic force microscopy. The concentration of 1 : z electrolytes is systematically varied to understand the behavior of electrostatic interactions and double-layer properties in these systems. Although the coions are multivalent the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory perfectly describes the measured force profiles. The diffuse-layer potentials and regulation properties are extracted from the forces profiles by using the DLVO theory. The dependencies of the diffuse-layer potential and regulation parameter shift to lower concentration with increasing coion valence when plotted as a function of concentration of 1 : z salt. Interestingly, these profiles collapse to a master curve if plotted as a function of monovalent counterion concentration.

Comparison of the AJCC, MSTS, and Modified Spanier Systems for Clinical and Pathologic Staging of Osteosarcoma.

PubMed

Cates, Justin M M

2017-03-01

The prognostic performance of the 2 most commonly used staging systems for skeletal sarcoma (the American Joint Committee on Cancer [AJCC] and Musculoskeletal Tumor Society [MSTS] systems) have never been compared analytically. Another staging system originally proposed by Spanier has not yet been validated. Given the recent release of the 8th edition of the AJCC Cancer Staging Manual, this study was designed to directly compare these anatomic staging systems in a series of 153 high-grade, intramedullary osteosarcomas. Kaplan-Meier curves were plotted and pairwise comparisons between each stage category were performed. Predictive accuracy of each staging system for determining 5-year disease-free survival was evaluated by comparing areas under receiver-operating characteristic curves generated from logistic regression analysis. Multiple concordance indices were calculated using bootstrapping methods (200 replications). ρk and R were estimated as measures of the variation in survival outcomes explained by the regression models. The AJCC, MSTS, and a modified version of the Spanier staging systems showed similar discriminatory abilities and no significant differences in the levels of contrast between different tumor stages across staging systems. Addition of T-category information from each staging system contributed significant prognostic information compared with a Cox proportional hazard regression model consisting only of the presence or absence of metastatic disease as a measure of disease extent. Concordance indices and predictive accuracy for 5-year disease-free survival were not significantly different among the different staging systems either. Similar findings were observed after accounting for other important prognostic variables. Additional studies are necessary to determine performance parameters of each staging system for other types of skeletal sarcoma. Prognostic performance of osteosarcoma staging systems would also be improved by incorporating nonanatomic prognostic variables into staging algorithms.

Present and Past Impact of Glacially Sourced Dust on Iron Fertilization of the Southern Ocean

NASA Astrophysics Data System (ADS)

Shoenfelt, E. M.; Winckler, G.; Kaplan, M. R.; Sambrotto, R.; Bostick, B. C.

2016-12-01

An increase in iron-containing dust flux and a more efficient biological pump in the Southern Ocean have been associated with the CO2 drawdown and global cooling of the Last Glacial Maximum (LGM). While iron (Fe) mineralogy is known to affect Fe bioavailability through its impact on Fe solubility, there are limited studies investigating the importance of Fe mineralogy in dust fluxes to the Southern Ocean, and no previous studies investigating interactions between eukaryotic phytoplankton and particulate-phase Fe in natural dusts applicable to Southern Ocean environments. Since physically weathered bedrock becomes less soluble as it becomes weathered and oxidized, we hypothesized that glacially sourced dusts would contain more Fe(II)-rich primary minerals and would be more bioavailable than dusts from areas not impacted by glaciers. We used a series of natural dusts from Patagonia as the sole Fe source in incubation experiments with the model diatom Phaeodactylum tricornutum, and evaluated Fe bioavailability using culture growth rates, cell density, and variable fluorescence. Monod curves were also used to evaluate the efficiency of the different particulates as sources of nutrient Fe. Using these Monod curves fit to growth rates plotted against particulate Fe concentrations, we observed that 1) Fe(II)-rich primary silicates were significantly more effective as an Fe source to diatoms than Fe(III)-rich oxides, that 2) Fe(II) content itself was responsible for the difference in Fe bioavailability/efficiency of the Fe nutrient source, and that 3) surface interactions with the particulates were important. In an effort to explore the possibility that Fe mineralogy impacted Fe bioavailability in past oceans, we will present our hypotheses regarding productivity and Fe mineralogy/bioavailability through the last glacial cycle.

Abdominal Twin Pressure Sensors for the assessment of abdominal injuries in Q dummies: in-dummy evaluation and performance in accident reconstructions.

PubMed

Beillas, Philippe; Alonzo, François; Chevalier, Marie-Christine; Lesire, Philippe; Leopold, Franck; Trosseille, Xavier; Johannsen, Heiko

2012-10-01

The Abdominal Pressure Twin Sensors (APTS) for Q3 and Q6 dummies are composed of soft polyurethane bladders filled with fluid and equipped with pressure sensors. Implanted within the abdominal insert of child dummies, they can be used to detect abdominal loading due to the belt during frontal collisions. In the present study - which is part of the EC funded CASPER project - two versions of APTS (V1 and V2) were evaluated in abdominal belt compression tests, torso flexion test (V1 only) and two series of sled tests with degraded restraint conditions. The results suggest that the two versions have similar responses, and that the pressure sensitivity to torso flexion is limited. The APTS ability to detect abdominal loading in sled tests was also confirmed, with peak pressures typically below 1 bar when the belt loaded only the pelvis and the thorax (appropriate restraint) and values above that level when the abdomen was loaded directly (inappropriate restraint). Then, accident reconstructions performed as part of CASPER and previous EC funded projects were reanalyzed. Selected data from 19 dummies (12 Q6 and 7 Q3) were used to plot injury risk curves. Maximum pressure, maximum pressure rate and their product were all found to be injury predictors. Maximum pressure levels for a 50% risk of AIS3+ were consistent with the levels separating appropriate and inappropriate restraint in the sled tests (e.g. 50% risk of AIS3+ at 1.09 bar for pressure filtered CFC180). Further work is needed to refine the scaling techniques between ages and confirm the risk curves.

Metaanalysis of recurrence after laparoscopic repair of paraesophageal hernia.

PubMed

Rathore, Munir Ahmad; Andrabi, Syed Imran Hussain; Bhatti, Muhammad Iqbal; Najfi, Syed Muzahir Hussain; McMurray, Arthur

2007-01-01

Recurrence and reflux are 2 most important remote complications of lap-paraesophageal hernia (PEH) repair. However, the extent of recurrence remains unknown. We sought to determine the true incidence of recurrence after lap-PEH repair. A meta-analysis was carried out. PubMed, EMBASE, Cochrane Library, hand search, and personal communication were used to access and appraise studies. The inclusion criteria were full-text papers published from 1991 to date that describe lap-PEH repair in >25 patients, have at least a 6-month follow-up, and address the issue of recurrence. "Wrap migration" papers were excluded. Papers were appraised and the data were isolated on summary sheets. MS Office Excel 2003 was used to plot the results and represent it in graphs. Thirteen studies were eligible (all retrospective case series). A total of 965 patients with 99 recurrences were noted. The overall recurrence rate (in all patients) was 10.2% and was 14% if only the followed up patients (n=658/965) were considered. However, when patients with objective evidence (follow-up Ba esophagogram) were used (301/965), the "true" recurrence rate was 25.5% (ie, 1 in 4 recurred). The learning curve did not appear to be an issue (P=0.27). The studies revealed broad 95 CI and touched the line-of-no-effect, thereby increasing the "chance factor." When an alternate model was applied, esophageal lengthening (by Collis-Nissen gastroplasty) revealed a significant protective influence (P<0.0001). The true incidence of lap-PEH recurrence is 25.5%. The learning curve is not an adequate explanation. Mandatory (protocol) follow-up esophagograms at 1 year are essential. Two emphasis points in the repair have emerged: hiatoplasty and (superadded) esophageal lengthening.

Comparison of the order of magnetic phase transitions in several magnetocaloric materials using the rescaled universal curve, Banerjee and mean field theory criteria

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

Burrola-Gándara, L. A., E-mail: andres.burrola@gmail.com; Santillan-Rodriguez, C. R.; Rivera-Gomez, F. J.

2015-05-07

Magnetocaloric materials with second order phase transition near the Curie temperature can be described by critical phenomena theory. In this theory, scaling, universality, and renormalization are key concepts from which several phase transition order criteria are derived. In this work, the rescaled universal curve, Banerjee and mean field theory criteria were used to make a comparison for several magnetocaloric materials including pure Gd, SmCo{sub 1.8}Fe{sub 0.2}, MnFeP{sub 0.46}As{sub 0.54}, and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}MnO{sub 3}. Pure Gd, SmCo{sub 1.8}Fe{sub 0.2}, and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}MnO{sub 3} present a collapse of the rescaled magnetic entropy change curves into a universal curve,more » which indicates a second order phase transition; applying Banerjee criterion to H/σ vs σ{sup 2} Arrot plots and the mean field theory relation |ΔS{sub M}| ∝ (μ{sub 0}H/T{sub c}){sup 2/3} for the same materials also determines a second order phase transition. However, in the MnFeP{sub 0.46}As{sub 0.54} sample, the Banerjee criterion applied to the H/σ vs σ{sup 2} Arrot plot indicates a first order magnetic phase transition, while the mean field theory prediction for a second order phase transition, |ΔS{sub M}| ∝ (μ{sub 0}H/T{sub c}){sup 2/3}, describes a second order behavior. Also, a mixture of first and second order behavior was indicated by the rescaled universal curve criterion. The diverse results obtained for each criterion in MnFeP{sub 0.46}As{sub 0.54} are apparently related to the magnetoelastic effect and to the simultaneous presence of weak and strong magnetism in Fe (3f) and Mn (3g) alternate atomic layers, respectively. The simultaneous application of the universal curve, the Banerjee and the mean field theory criteria has allowed a better understanding about the nature of the order of the phase transitions in different magnetocaloric materials.« less

Light-Curve Survey of Jupiter Trojan Asteroids

NASA Astrophysics Data System (ADS)

Duffard, R.; Melita, M.; Ortiz, J. L.; Licandro, J.; Williams, I. P.; Jones, D.

2008-09-01

Trojan asteroids are an interesting population of minor bodies due to their dynamical characteristics, their physical properties and that they are relatively isolated located at the snow-line The main hypotheses about the origin of the Jupiter Trojans assumed that they formed either during the final stages of the planetary formation (Marzari & Scholl 1998), or during the epoch of planetary migration (Morbidelli et al. 2005), in any case more than 3.8 Gy. ago. The dynamical configuration kept the Trojans isolated from the asteroid Main Belt throughout the history of the Solar System. In spite of eventual interactions with other populations of minor bodies like the Hildas, the Jupiter family comets, and the Centaurs, their collisional evolution has been dictated mostly by the intrapopulation collisions (Marzari et al. 1996, 1997). Therefore, the Jupiter Trojans may be considered primordial bodies, whose dynamical and physical properties can provide important clues about the environment of planetary formation. The available sample of Jupiter Trojans light-curves is small and mainly restricted to the largest objects. According to the MPC-website (updated last in March 2006), the present sample of rotation periods and light-curve-amplitudes of the Jupiter Trojan asteroids is composed by 25 objects with some information about their periods and by 10 of them with only an amplitude estimation. A survey of contact binary Trojan asteroids has been done by Mann et al. 2007, where they have recorded more than 100 amplitudes from sparse-sampled light-curves and very-wellresolved rotational periods. More than 2000 Trojan asteroids have been discovered up to date, so, there is an urgent need to enlarge the sample of intrinsic rotation periods and accurate light-curve amplitudes and to extend it to smaller sizes. Results and Discusions We requested 26 nights of observation in the second semester of 2007, to begin with the survey. They were scheduled for the following instruments: the WFC, Isaac Newton Telescope (ING, 2.5m, 7 nights), CAHA (2.2m, 6 nights), CCD direct OSN (1.5m, 6 nights) and CCD direct, JS (CASLEO, 2.15m, 7 nights). From these observations we have constructed the differential photometry light-curves of 15 Trojan asteroids. Plots showing the actual light curves and the quality assessment of our estimation of the rotational period can be downloaded from: http://www.df.uba.ar/users/melita/PICT07/PICT07.ht ml. See table 1 for the main results. In figure 1 we show the known periods of the Trojan asteroids as a function of their size. Some of these data are still of poor quality. It remains to be confirmed the reality of the clustering of small objects at small periods, so, there is a need to improve those rotation rates with reliable standard photometry produced at an instrument of larger aperture. Also, a lack of data for the biggest objects is apparent from this figure. In figure 2 we show a plot of the Rmagnitude amplitude variation as a function of the absolute magnitude. Most of the objects are from the survey of contact binaries by Mann et al. 2007. This plot seems to indicate that the extreme elongations recorded previously are constrained to the largest objects. Our data follows the trend of a negative slope, but given the error-bars involved, it remains to be confirmed if smaller objects tend to be more spherical.

[Study on extraction method of Panax notoginseng plots in Wenshan of Yunnan province based on decision tree model].

PubMed

Shi, Ting-Ting; Zhang, Xiao-Bo; Guo, Lan-Ping; Huang, Lu-Qi

2017-11-01

The herbs used as the material for traditional Chinese medicine are always planted in the mountainous area where the natural environment is suitable. As the mountain terrain is complex and the distribution of planting plots is scattered, the traditional survey method is difficult to obtain accurate planting area. It is of great significance to provide decision support for the conservation and utilization of traditional Chinese medicine resources by studying the method of extraction of Chinese herbal medicine planting area based on remote sensing and realizing the dynamic monitoring and reserve estimation of Chinese herbal medicines. In this paper, taking the Panax notoginseng plots in Wenshan prefecture of Yunnan province as an example, the China-made GF-1multispectral remote sensing images with a 16 m×16 m resolution were obtained. Then, the time series that can reflect the difference of spectrum of P. notoginseng shed and the background objects were selected to the maximum extent, and the decision tree model of extraction the of P. notoginseng plots was constructed according to the spectral characteristics of the surface features. The results showed that the remote sensing classification method based on the decision tree model could extract P. notoginseng plots in the study area effectively. The method can provide technical support for extraction of P. notoginseng plots at county level. Copyright© by the Chinese Pharmaceutical Association.

Van Allen Probes Science Gateway: A Centralized Data Access Point

NASA Astrophysics Data System (ADS)

Romeo, G.; Barnes, R. J.; Ukhorskiy, A. Y.; Sotirelis, T.; Stephens, G. K.; Kessel, R.; Potter, M.

2015-12-01

The Van Allen Probes Science Gateway acts a centralized interface to the instrument Science Operation Centers (SOCs), provides mission planning tools, and hosts a number of science related activities such as the mission bibliography. Most importantly, the Gateway acts as the primary site for processing and delivering the Van Allen Probes Space Weather data to users. Over the past years, the web-site has been completely redesigned with the focus on easier navigation and improvements of the existing tools such as the orbit plotter, position calculator and magnetic footprint tool. In addition, a new data plotting facility has been added. Based on HTML5, which allows users to interactively plot Van Allen Probes science and space weather data. The user can tailor the tool to display exactly the plot they wish to see and then share this with other users via either a URL or by QR code. Various types of plots can be created, including, simple time series, data plotted as a function of orbital location, and time versus L-Shell, capability of visualizing data from both probes (A & B) on the same plot. In cooperation with all Van Allen Probes Instrument SOCs, the Science Gateway will soon be able to serve higher level data products (Level 3), and to visualize them via the above mentioned HTML5 interface. Users will also be able to create customized CDF files on the fly.

Scaling and the frequency dependence of Nyquist plot maxima of the electrical impedance of the human thigh.

PubMed

Shiffman, Carl

2017-11-30

To define and elucidate the properties of reduced-variable Nyquist plots. Non-invasive measurements of the electrical impedance of the human thigh. A retrospective analysis of the electrical impedances of 154 normal subjects measured over the past decade shows that 'scaling' of the Nyquist plots for human thigh muscles is a property shared by healthy thigh musculature, irrespective of subject and the length of muscle segment. Here the term scaling signifies the near and sometimes 'perfect' coalescence of the separate X versus R plots into one 'reduced' Nyquist plot by the simple expedient of dividing R and X by X m , the value of X at the reactance maximum. To the extent allowed by noise levels one can say that there is one 'universal' reduced Nyquist plot for the thigh musculature of healthy subjects. There is one feature of the Nyquist curves which is not 'universal', however, namely the frequency f m at which the maximum in X is observed. That is found to vary from 10 to 100 kHz. depending on subject and segment length. Analysis shows, however, that the mean value of 1/f m is an accurately linear function of segment length, though there is a small subject-to-subject random element as well. Also, following the recovery of an otherwise healthy victim of ankle fracture demonstrates the clear superiority of measurements above about 800 kHz, where scaling is not observed, in contrast to measurements below about 400 kHz, where scaling is accurately obeyed. The ubiquity of 'scaling' casts new light on the interpretation of impedance results as they are used in electrical impedance myography and bioelectric impedance analysis.

Tuning metal-to-metal charge transfer of mixed-valence complexes containing ferrocenylpyridine and rutheniumammines via solvent donicity and substituent effects.

PubMed

Chen, Y J; Kao, C H; Lin, S J; Tai, C C; Kwan, K S

2000-01-24

A homogeneous series of heterobimetallic complexes of [R-Fc(4-py)Ru(NH3)5](PF6)2 (R = H, Et, Br, acetyl; Fc(4-py) = 4-ferrocenylpyridine) have been prepared and characterized. The mixed-valence species generated in situ using ferrocenium hexafluorophosphate as the oxidant show class II behavior, and the oxidized sites are ruthenium centered. deltaE(1/2), E(1/2)(Fe(III)/Fe(II)) - E(1/2)(Ru(III)/Ru(II)), an upper limit for deltaGo that is an energetic difference between the donor and acceptor sites, changes sharply and linearly with Gutmann solvent donor number (DN) and Hammett substituent constants (sigma). The solvent-dependent and substituent-dependent intervalence transfer bands were found to vary almost exclusively with deltaE(1/2). The activation energy for the optical electron transfer versus deltaE(1/2) plot yields a common nuclear reorganization energy (lambda) of 0.74 +/- 0.04 eV for this series. The equation that allows one to incorporate the effect of both solvent donicity and substituents on optical electron transfer is Eop = lambda + deltaGo, where deltaGo = (deltaGo)intrinsic + (deltaGo)solvent donicity + (deltaGo)substituent effect (deltaGo )intinnsic with a numerical value of 0.083 +/- 0.045 eV was obtained from the intercept of the deltaE(1/2) of [H-Fc(4-py)Ru(NH3)5]2+,3+,4+ versus DN plot. (deltaGo)solvent donicity was obtained from the average slopes of the deltaE(1/2) of [R-Fc-(4-py)Ru(NH3)5]2+,3+,4+ versus DN plot, and (deltaGo)substituent effect was obtained from the average slopes of the corresponding deltaE(1/2) versus sigma plot. The empirical equation allows one to finely tune Eop of this series to Eop = 0.82 + 0.019(DN) + 0.44sigma eV at 298 K, and the discrepancy between the calculated and experimental data is less than 6%.

Induction treatments for acute promyelocytic leukemia: a network meta-analysis

PubMed Central

Zhang, Qiaoxia; Lou, Jin; Cai, Yun; Chen, Weihong; Du, Xin

2016-01-01

Background 9 treatments for acute promyelocytic leukemia (APL) have been compared in many randomized controlled trials (RCT). The conclusions have been inconsistent and the purpose of this study is to conduct a network meta-analysis. Results Rankings of event-free survival are ATRA+RIF (81.2%), ATRA+ATO (69.6%), ATO (50.6%). Rankings of complete remission are ATRA+RIF (79.3%), ATRA+ATO (64.8%), RIF (60.3%), ATO (55.9%). Rankings of avoiding differentiation syndromes are CT (84.3%), ATO (80.3%), RIF (71.6%), ATRA+RIF (49%), ATRA+ATO (40.8%). Methods A total of 1,666 patients from 12 RCTs were enrolled. The frequentist method was used. Relative risks with 95% confidence intervals were calculated. We produced a network plot, a contribution plot, and a forest plot predictive intervals. The inconsistency factor, the surface under the cumulative ranking curve and the publication bias were evaluated. Conclusions ATRA+ATO is eligible to be the first-line treatment for APL. ATRA+RIF is a prospective alternative to the first-line treatment. RIF or ATO should be reconsidered as another option for de novo APL. PMID:27713127

External validation and comparison of two nomograms predicting the probability of Gleason sum upgrading between biopsy and radical prostatectomy pathology in two patient populations: a retrospective cohort study.

PubMed

Utsumi, Takanobu; Oka, Ryo; Endo, Takumi; Yano, Masashi; Kamijima, Shuichi; Kamiya, Naoto; Fujimura, Masaaki; Sekita, Nobuyuki; Mikami, Kazuo; Hiruta, Nobuyuki; Suzuki, Hiroyoshi

2015-11-01

The aim of this study is to validate and compare the predictive accuracy of two nomograms predicting the probability of Gleason sum upgrading between biopsy and radical prostatectomy pathology among representative patients with prostate cancer. We previously developed a nomogram, as did Chun et al. In this validation study, patients originated from two centers: Toho University Sakura Medical Center (n = 214) and Chibaken Saiseikai Narashino Hospital (n = 216). We assessed predictive accuracy using area under the curve values and constructed calibration plots to grasp the tendency for each institution. Both nomograms showed a high predictive accuracy in each institution, although the constructed calibration plots of the two nomograms underestimated the actual probability in Toho University Sakura Medical Center. Clinicians need to use calibration plots for each institution to correctly understand the tendency of each nomogram for their patients, even if each nomogram has a good predictive accuracy. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Students' challenges with polar functions: covariational reasoning and plotting in the polar coordinate system

NASA Astrophysics Data System (ADS)

Habre, Samer

2017-01-01

Covariational reasoning has been the focus of many studies but only a few looked into this reasoning in the polar coordinate system. In fact, research on student's familiarity with polar coordinates and graphing in the polar coordinate system is scarce. This paper examines the challenges that students face when plotting polar curves using the corresponding plot in the Cartesian plane. In particular, it examines how students coordinate the covariation in the polar coordinate system with the covariation in the Cartesian one. The research, which was conducted in a sophomore level Calculus class at an American university operating in Lebanon, investigates in addition the challenges when students synchronize the reasoning between the two coordinate systems. For this, the mental actions that students engage in when performing covariational tasks are examined. Results show that coordinating the value of one polar variable with changes in the other was well achieved. Coordinating the direction of change of one variable with changes in the other variable was more challenging for students especially when the radial distance r is negative.

A GIS tool for modelling annual diffuse infiltration on a plot scale

NASA Astrophysics Data System (ADS)

España, Salvador; Alcalá, Francisco J.; Vallejos, Ángela; Pulido-Bosch, Antonio

2013-04-01

ArcB is a GIS tool for modelling annual diffuse infiltration (RP) from precipitation (P) on a plot scale that uses ArcObjects as the programming language to incorporate equations and boundary conditions for the water-balance consistency. Because detailed weather, soil, and vegetation data are often missing, ArcB uses well-known non-global models such as Hargreaves for daily potential evapotranspiration and Budyko for annual actual evapotranspiration (EA), as well as the SCS Curve Number procedure for 24-h plot runoff (RO). Annual RP is quantified as the difference in annual P, EA, and RO. Because the use of non-global models for EA may induce suboptimal RP results, ArcB allows corrections of EA estimates by comparisons with data from a reference station. In a semiarid heterogeneous region in south-eastern Spain, the uncertainty of RO and RP was lowered to 4% and 2%, respectively, when correcting EA. ArcObjects is a versatile programming language which allows advanced users to incorporate more complex formulations for more accurate results as detailed data is acquired and to develop routines for calibration when reference data exist.

User interface user's guide for HYPGEN

NASA Technical Reports Server (NTRS)

Chiu, Ing-Tsau

1992-01-01

The user interface (UI) of HYPGEN is developed using Panel Library to shorten the learning curve for new users and provide easier ways to run HYPGEN for casual users as well as for advanced users. Menus, buttons, sliders, and type-in fields are used extensively in UI to allow users to point and click with a mouse to choose various available options or to change values of parameters. On-line help is provided to give users information on using UI without consulting the manual. Default values are set for most parameters and boundary conditions are determined by UI to further reduce the effort needed to run HYPGEN; however, users are free to make any changes and save it in a file for later use. A hook to PLOT3D is built in to allow graphics manipulation. The viewpoint and min/max box for PLOT3D windows are computed by UI and saved in a PLOT3D journal file. For large grids which take a long time to generate on workstations, the grid generator (HYPGEN) can be run on faster computers such as Crays, while UI stays at the workstation.

Tools for computer graphics applications

NASA Technical Reports Server (NTRS)

Phillips, R. L.

1976-01-01

Extensive research in computer graphics has produced a collection of basic algorithms and procedures whose utility spans many disciplines. These tools are described in terms of their fundamental aspects, implementations, applications, and availability. Programs which are discussed include basic data plotting, curve smoothing, and depiction of three dimensional surfaces. As an aid to potential users of these tools, particular attention is given to discussing their availability and, where applicable, their cost.

Evaluation of MSFC-STD-486, ''Threaded Fasteners, Torque Limits For'' for use in the construction of aerospace vhicles

NASA Technical Reports Server (NTRS)

Hart, J. F.

1973-01-01

MSFC-STD-486, Threaded Fasteners, Torque Limits For, is a relatively new standard that has not had much user experience. This test was run to provide such experience and verify the values in MSFC-STD-486. This was accomplished by plotting torque-tension curves on aluminum and alloy steel aircraft quality bolts and nuts through 1/2 inch in diameter.

Activation energy of the low-load NaCl transition from nanoindentation loading curves.

PubMed

Kaupp, Gerd

2014-01-01

Access to activation energies E(a) of phase transitions is opened by unprecedented analyses of temperature dependent nanoindentation loading curves. It is based on kinks in linearized loading curves, with additional support by coincidence of kink and electrical conductivity of silicon loading curves. Physical properties of B1, B2, NaCl and further phases are discussed. The normalized low-load transition energy of NaCl (Wtrans/µN) increases with temperature and slightly decreases with load. Its semi-logarithmic plot versus T obtains activation energy E(a)/µN for calculation of the transition work for all interesting temperatures and pressures. Arrhenius-type activation energy (kJ/mol) is unavailable for indentation phase transitions. The E(a) per load normalization proves insensitive to creep-on-load, which excludes normalization to depth or volume for large temperature ranges. Such phase transition E(a)/µN is unprecedented material's property and will be of practical importance for the compatibility of composite materials under impact and further shearing interactions at elevated temperatures. © 2014 Wiley Periodicals, Inc.

Study of the magnetic interaction in nanocrystalline Pr-Fe-Co-Nb-B permanent magnets

NASA Astrophysics Data System (ADS)

Dospial, M.; Plusa, D.; Ślusarek, B.

2012-03-01

The magnetic properties of an isotropic, epoxy resin bonded magnets made from Pr-Fe-Co-Nb-B powder were investigated. The magnetization reversal process and magnetic parameters were examined by measurements of the initial magnetization curve, major and minor hysteresis loops and sets of recoil curves. From the initial magnetization curve and the field dependencies of the reversible and irreversible magnetization components derived from the recoil loops it was found that the magnetization reversal process is the combination of the nucleation of reversed domains and pinning of domain walls at the grain boundaries and the reversible rotation of magnetization vector in single domain grains. The interactions between grains were studied by means of δM plots. The nonlinear behavior of δM curve approve that the short range intergrain exchange coupling interactions are dominant in a field up to the sample coercivity. The interaction domains and fine magnetic structure were revealed as the evidence of exchange coupling between soft α-Fe and hard magnetic Nd2Fe14B grains.

IN VITRO MEASUREMENT OF TOTAL ANTIOXIDANT CAPACITY OF CRATAEGUS MACRACANTHA LODD LEAVES.

PubMed

Miftode, Alina Monica; Stefanache, Alina; Spac, A F; Miftode, R F; Miron, Anca; Dorneanu, V

2016-01-01

Crataegus macracantha Lodd, family Rosaceae, is a very rare species in Europe, and unlike Crataegus monogyna is less investigated for pharmacologic activity. To analyze the ability of the lyophilisate of extract obtained from leaves of Crataegus macracantha Lodd (single plant at the Iaşi Botanical Garden) to capture free radicals in vitro. The lyophilisate obtained in Department of Pharmacognosy, Faculty of Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy Iaşi. The decreased absorbance of chromophore chlorpromazine radical cation in the presence of the lyophilized solutions was studied spectrophotometrically. The indicator radical cation, obtained by oxidation of chlorpromazine by potassium persulfate, has the maximum absorbance at 525 nm. Ascorbic acid was used as a standard antioxidant. The absorbance of radical solution was determined after the addition of a certain amount of lyophilisate at different time intervals. The antioxidant activity was calculated using the calibration curve obtained by plotting the variation in radical solution absorbance depending on ascorbic acid concentration. For each ascorbic acid concentration the area under the curve was calculated from plotting the percentage inhibition of the absorbance at two pre-established time intervals. The results confirm the antioxidant activity of the leaves of Crataegus Macracantha Lodd and by optimizing the proposed analytical methods the antiradical activity can be quickly evaluated with minimal reagent consumption.

Disentangling random thermal motion of particles and collective expansion of source from transverse momentum spectra in high energy collisions

NASA Astrophysics Data System (ADS)

Wei, Hua-Rong; Liu, Fu-Hu; Lacey, Roy A.

2016-12-01

In the framework of a multisource thermal model, we describe experimental results of the transverse momentum spectra of final-state light flavor particles produced in gold-gold (Au-Au), copper-copper (Cu-Cu), lead-lead (Pb-Pb), proton-lead (p-Pb), and proton-proton (p -p) collisions at various energies, measured by the PHENIX, STAR, ALICE, and CMS Collaborations, by using the Tsallis-standard (Tsallis form of Fermi-Dirac or Bose-Einstein), Tsallis, and two- or three-component standard distributions which can be in fact regarded as different types of ‘thermometers’ or ‘thermometric scales’ and ‘speedometers’. A central parameter in the three distributions is the effective temperature which contains information on the kinetic freeze-out temperature of the emitting source and reflects the effects of random thermal motion of particles as well as collective expansion of the source. To disentangle both effects, we extract the kinetic freeze-out temperature from the intercept of the effective temperature (T) curve as a function of particle’s rest mass (m 0) when plotting T versus m 0, and the mean transverse flow velocity from the slope of the mean transverse momentum (< {p}T> ) curve as a function of mean moving mass (\\overline{m}) when plotting < {p}T> versus \\overline{m}.

Codon Usage Bias and Determining Forces in Taenia solium Genome.

PubMed

Yang, Xing; Ma, Xusheng; Luo, Xuenong; Ling, Houjun; Zhang, Xichen; Cai, Xuepeng

2015-12-01

The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome.

Application of decline curve analysis to estimate recovery factors for carbon dioxide enhanced oil recovery

USGS Publications Warehouse

Jahediesfanjani, Hossein

2017-07-17

IntroductionIn the decline curve analysis (DCA) method of estimating recoverable hydrocarbon volumes, the analyst uses historical production data from a well, lease, group of wells (or pattern), or reservoir and plots production rates against time or cumu­lative production for the analysis. The DCA of an individual well is founded on the same basis as the fluid-flow principles that are used for pressure-transient analysis of a single well in a reservoir domain and therefore can provide scientifically reasonable and accurate results. However, when used for a group of wells, a lease, or a reservoir, the DCA becomes more of an empirical method. Plots from the DCA reflect the reservoir response to the oil withdrawal (or production) under the prevailing operating and reservoir conditions, and they continue to be good tools for estimating recoverable hydrocarbon volumes and future production rates. For predicting the total recov­erable hydrocarbon volume, the DCA results can help the analyst to evaluate the reservoir performance under any of the three phases of reservoir productive life—primary, secondary (waterflood), or tertiary (enhanced oil recovery) phases—so long as the historical production data are sufficient to establish decline trends at the end of the three phases.

Comparison of currents predicted by NASCAP/LEO model simulations with elementary Langmuir-type bare probe models for an insulated cable containing a single pinhole

NASA Technical Reports Server (NTRS)

Galofaro, Joel T.

1990-01-01

The behavior of a defect in the insulation of a short biased section of cable in a Low Earth Orbit (LEO) space environment was examined. Such studies are of the utmost importance for large space power systems where great quantities of cabling will be deployed. An insulated probe containing a pinhole was placed into a hypothetical high speed LEO plasma. The NASA Charging Analyzer Program (NASCAP/LEO) was used to explore sheath growth about the probe as a function of applied voltage and to predict I-V behavior. A set of independent current calculations using Langmuir's formulations for concentric spheres and coaxial cylinders were also performed. The case of concentric spheres was here extended to include the case of concentric hemispheres. Several simple Langmuir-type models were then constructed to bracket the current collected by the cable. The space-charge sheath radius and impact parameters were used to determine the proper current regime. I-V curves were plotted for the models and comparisons were made with NASCAP/LEO results. Finally, NASCAP/LEO potential contours and surface cell potential plots were examined to explain interesting features in the NASCAP/LEO I-V curve.

Testing and analysis of flat and curved panels with multiple cracks

NASA Technical Reports Server (NTRS)

Broek, David; Jeong, David Y.; Thomson, Douglas

1994-01-01

An experimental and analytical investigation of multiple cracking in various types of test specimens is described in this paper. The testing phase is comprised of a flat unstiffened panel series and curved stiffened and unstiffened panel series. The test specimens contained various configurations for initial damage. Static loading was applied to these specimens until ultimate failure, while loads and crack propagation were recorded. This data provides the basis for developing and validating methodologies for predicting linkup of multiple cracks, progression to failure, and overall residual strength. The results from twelve flat coupon and ten full scale curved panel tests are presented. In addition, an engineering analysis procedure was developed to predict multiple crack linkup. Reasonable agreement was found between predictions and actual test results for linkup and residual strength for both flat and curved panels. The results indicate that an engineering analysis approach has the potential to quantitatively assess the effect of multiple cracks in the arrest capability of an aircraft fuselage structure.

Heterosynaptic changes accompany long-term but not short-term potentiation of the perforant path in the anaesthetized rat.

PubMed

Abraham, W C; Bliss, T V; Goddard, G V

1985-06-01

Brief high-frequency trains of electrical stimulation delivered to the perforant path result in long-term potentiation (l.t.p.) of field potentials recorded extracellularly from granule cells of the dentate gyrus. L.t.p. of the population spike is often disproportionately greater than l.t.p. of the population excitatory post-synaptic potential (e.p.s.p.). We have investigated the basis of this effect in rats anaesthetized with sodium pentobarbitone. A series of graded stimuli were given before and after tetanization of the perforant path. From data obtained in this way, we plotted stimulus-response curves, and the relation (E-S curve) between the slope of the population e.p.s.p. (E) and the amplitude of the population spike (S). Curves relating spike onset latency to the slope of the e.p.s.p. were also constructed. Tetanization of the combined medial and lateral components of the perforant path led to long-term changes in the relation between the e.p.s.p. and the population spike. For a given e.p.s.p., the corresponding population spike was of greater amplitude and earlier onset. This E-S potentiation was marked by a shift to the left of the E-S amplitude curve and a downward displacement of the E-S latency curve. Tetanization of the lateral component of the perforant path had two long-term effects on responses evoked by test stimuli to the untetanized medial component: (1) long-term depression of the medial e.p.s.p. and (2) long-term E-S potentiation. The net result of these two heterosynaptically induced effects was to leave unaltered information transfer across medial perforant path-granule cell synapses; for a given test volley the e.p.s.p. was smaller, but because of E-S potentiation the population spike remained relatively unaffected. Short-term potentiation, which has a time course of only a few minutes and is presumed to be mediated by presynaptic mechanisms, was not accompanied by E-S potentiation or by corresponding changes in spike latency. Possible mechanisms of long-term heterosynaptic depression of the e.p.s.p. and of homo- and heterosynaptic E-S potentiation, are discussed. We conclude that although these effects probably reflect a generalized post-synaptic change, this change is unlikely to be a prolonged reduction in the membrane potential of granule cells.

Hydraulic modeling of riverbank filtration systems with curved boundaries using analytic elements and series solutions

NASA Astrophysics Data System (ADS)

Bakker, Mark

2010-08-01

A new analytic solution approach is presented for the modeling of steady flow to pumping wells near rivers in strip aquifers; all boundaries of the river and strip aquifer may be curved. The river penetrates the aquifer only partially and has a leaky stream bed. The water level in the river may vary spatially. Flow in the aquifer below the river is semi-confined while flow in the aquifer adjacent to the river is confined or unconfined and may be subject to areal recharge. Analytic solutions are obtained through superposition of analytic elements and Fourier series. Boundary conditions are specified at collocation points along the boundaries. The number of collocation points is larger than the number of coefficients in the Fourier series and a solution is obtained in the least squares sense. The solution is analytic while boundary conditions are met approximately. Very accurate solutions are obtained when enough terms are used in the series. Several examples are presented for domains with straight and curved boundaries, including a well pumping near a meandering river with a varying water level. The area of the river bottom where water infiltrates into the aquifer is delineated and the fraction of river water in the well water is computed for several cases.

Effect of Season on the Persistence of Bacterial Pathogens in Runoff from Agricultural Plots

EPA Science Inventory

Runoff from agricultural fields undergoing manure applications may carry a variety of chemical and microbial contaminants that compromise water quality and increase the possibility of human exposure to pathogenic microorganisms when recreational waters are impacted. A series of r...

Long-term vegetation monitoring in Great Britain - the Countryside Survey 1978-2007 and beyond

NASA Astrophysics Data System (ADS)

Wood, Claire M.; Smart, Simon M.; Bunce, Robert G. H.; Norton, Lisa R.; Maskell, Lindsay C.; Howard, David C.; Scott, W. Andrew; Henrys, Peter A.

2017-07-01

The Countryside Survey (CS) of Great Britain provides a globally unique series of datasets, consisting of an extensive set of repeated ecological measurements at a national scale, covering a time span of 29 years. CS was first undertaken in 1978 to monitor ecological and land use change in Britain using standardised procedures for recording ecological data from representative 1 km squares throughout the country. The same sites, with some additional squares, were used for subsequent surveys of vegetation undertaken in 1990, 1998 and 2007, with the intention of future surveys. Other data records include soils, freshwater habitats and invertebrates, and land cover and landscape feature diversity and extents. These data have been recorded in the same locations on analogous dates. However, the present paper describes only the details of the vegetation surveys. The survey design is a series of gridded, stratified, randomly selected 1 km squares taken as representative of classes derived from a statistical environmental classification of Britain. In the 1978 survey, 256 one-kilometre sample squares were recorded, increasing to 506 in 1990, 569 in 1998 and 591 in 2007. Initially each square contained up to 11 dispersed vegetation plots but additional plots were later placed in different features so that eventually up to 36 additional sampling plots were recorded, all of which can be relocated where possible (unless the plot has been lost, for example as a consequence of building work), providing a total of 16 992 plots by 2007. Plots are estimated to have a precise relocation accuracy of 85 %. A range of plots located in different land cover types and landscape features (for example, field boundaries) are included. Although a range of analyses have already been carried out, with changes in the vegetation being related to a range of drivers at local and national scales, there is major potential for further analyses, for example in relation to climate change. Although the precise locations of the plots are restricted, largely for reasons of landowner confidentiality, sample sites are intended to be representative of larger areas, and many potential opportunities for further analyses remain. Data from each of the survey years (1978, 1990, 1998, 2007) are available via the following DOIs: Countryside Survey 1978 vegetation plot data (https://doi.org/10.5285/67bbfabb-d981-4ced-b7e7-225205de9c96), Countryside Survey 1990 vegetation plot data (https://doi.org/10.5285/26e79792-5ffc-4116-9ac7-72193dd7f191), Countryside Survey 1998 vegetation plot data (https://doi.org/10.5285/07896bb2-7078-468c-b56d-fb8b41d47065), Countryside Survey 2007 vegetation plot data (https://doi.org/10.5285/57f97915-8ff1-473b-8c77-2564cbd747bc).

Pairing preferences of the model mono-valence mono-atomic ions investigated by molecular simulation

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

Zhang, Qiang; Department of Chemistry, Bohai University, Jinzhou 121000; Zhang, Ruiting

2014-05-14

We carried out a series of potential of mean force calculations to study the pairing preferences of a series of model mono-atomic 1:1 ions with evenly varied sizes. The probabilities of forming the contact ion pair (CIP) and the single water separate ion pair (SIP) were presented in the two-dimensional plots with respect to the ion sizes. The pairing preferences reflected in these plots largely agree with the empirical rule of matching ion sizes in the small and big size regions. In the region that the ion sizes are close to the size of the water molecule; however, a significantmore » deviation from this conventional rule is observed. Our further analysis indicated that this deviation originates from the competition between CIP and the water bridging SIP state. The competition is mainly an enthalpy modulated phenomenon in which the existing of the water bridging plays a significant role.« less

Multi-Scale Mapping of Vegetation Biomass

NASA Astrophysics Data System (ADS)

Hudak, A. T.; Fekety, P.; Falkowski, M. J.; Kennedy, R. E.; Crookston, N.; Smith, A. M.; Mahoney, P.; Glenn, N. F.; Dong, J.; Kane, V. R.; Woodall, C. W.

2016-12-01

Vegetation biomass mapping at multiple scales is important for carbon inventory and monitoring, reporting, and verification (MRV). Project-level lidar collections allow biomass estimation with high confidence where associated with field plot measurements. Predictive models developed from such datasets are customarily used to generate landscape-scale biomass maps. We tested the feasibility of predicting biomass in landscapes surveyed with lidar but without field plots, by withholding plot datasets from a reduced model applied to the landscapes, and found support for a generalized model in the northern Idaho ecoregion. We are also upscaling a generalized model to all forested lands in Idaho. Our regional modeling approach is to sample the 30-m biomass predictions from the landscape-scale maps and use them to train a regional biomass model, using Landsat time series, topographic derivatives, and climate variables as predictors. Our regional map validation approach is to aggregate the regional, annual biomass predictions to the county level and compare them to annual county-level biomass summarized independently from systematic, field-based, annual inventories conducted by the US Forest Inventory and Analysis (FIA) Program nationally. A national-scale forest cover map generated independently from 2010 PALSAR data at 25-m resolution is being used to mask non-forest pixels from the aggregations. Effects of climate change on future regional biomass stores are also being explored, using biomass estimates projected from stand-level inventory data collected in the National Forests and comparing them to FIA plot data collected independently on public and private lands, projected under the same climate change scenarios, with disturbance trends extracted from the Landsat time series. Our ultimate goal is to demonstrate, focusing on the ecologically diverse Northwest region of the USA, a carbon monitoring system (CMS) that is accurate, objective, repeatable, and transparent.

Development of a computer program to obtain ordinates for NACA 4-digit, 4-digit modified, 5-digit, and 16 series airfoils

NASA Technical Reports Server (NTRS)

Ladson, C. L.; Brooks, Cuyler W., Jr.

1975-01-01

A computer program developed to calculate the ordinates and surface slopes of any thickness, symmetrical or cambered NACA airfoil of the 4-digit, 4-digit modified, 5-digit, and 16-series airfoil families is presented. The program produces plots of the airfoil nondimensional ordinates and a punch card output of ordinates in the input format of a readily available program for determining the pressure distributions of arbitrary airfoils in subsonic potential viscous flow.

PROMIS series. Volume 8: Midlatitude ground magnetograms

NASA Technical Reports Server (NTRS)

Fairfield, D. H.; Russell, C. T.

1990-01-01

This is the eighth in a series of volumes pertaining to the Polar Region Outer Magnetosphere International Study (PROMIS). This volume contains 24 hour stack plots of 1-minute average, H and D component, ground magnetograms for the period March 10 through June 16, 1986. Nine midlatitude ground stations were selected from the UCLA magnetogram data base that was constructed from all available digitized magnetogram stations. The primary purpose of this publication is to allow users to define universal times and onset longitudes of magnetospheric substorms.

The role of enzyme and substrate concentration in the evaluation of serum angiotensin converting enzyme (ACE) inhibition by enalaprilat in vitro.

PubMed

Weisser, K; Schloos, J

1991-10-09

The relationship between serum angiotensin converting enzyme (ACE) activity and concentration of the ACE inhibitor enalaprilat was determined in vitro in the presence of different concentrations (S = 4-200 mM) of the substrate Hip-Gly-Gly. From Henderson plots, a competitive tight-binding relationship between enalaprilat and serum ACE was found yielding a value of approximately 5 nM for serum ACE concentration (Et) and an inhibition constant (Ki) for enalaprilat of approximately 0.1 nM. A plot of reaction velocity (Vi) versus total inhibitor concentration (It) exhibited a non-parallel shift of the inhibition curve to the right with increasing S. This was reflected by apparent Hill coefficients greater than 1 when the commonly used inhibitory sigmoid concentration-effect model (Emax model) was applied to the data. Slopes greater than 1 were obviously due to discrepancies between the free inhibitor concentration (If) present in the assay and It plotted on the abscissa and could, therefore, be indicators of tight-binding conditions. Thus, the sigmoid Emax model leads to an overestimation of Ki. Therefore, a modification of the inhibitory sigmoid Emax model (called "Emax tight model") was applied, which accounts for the depletion of If by binding, refers to It and allows estimation of the parameters Et and IC50f (free concentration of inhibitor when 50% inhibition occurs) using non-linear regression analysis. This model could describe the non-symmetrical shape of the inhibition curves and the results for Ki and Et correlated very well with those derived from the Henderson plots. The latter findings confirm that the degree of ACE inhibition measured in vitro is, in fact, dependent on the concentration of substrate and enzyme present in the assay. This is of importance not only for the correct evaluation of Ki but also for the interpretation of the time course of serum ACE inhibition measured ex vivo. The non-linear model has some advantages over the linear Henderson equation: it is directly applicable without conversion of the data and avoids the stochastic dependency of the variables, allowing non-linear regression of all data points contributing with the same weight.

Interactions and competition processes among tree species in young experimental mixed forests, assessed with chlorophyll fluorescence and leaf morphology.

PubMed

Pollastrini, M; Holland, V; Brüggemann, W; Koricheva, J; Jussila, I; Scherer-Lorenzen, M; Berger, S; Bussotti, F

2014-03-01

Chlorophyll a fluorescence (ChlF) and leaf morphology were assessed in two sites in Europe (Kaltenborn, Germany, and Satakunta, Finland) within a forest diversity experiment. Trees at Satakunta, planted in 1999, form a stratified canopy, while in Kaltenborn the trees are 7 years old, with no apparent canopy connection among broadleaf species. The following ChlF parameters from measured OJIP transient curves were examined: F(V)/F(M) (a proxy for maximum quantum yield); ΨEo (a proxy for efficiency in transferring an electron from reduced QA to the electron transport chain); I-P phase (a proxy for efficiency of reducing final acceptors beyond PSI); and PItot (total performance index for potential energy conservation from photons absorbed by PSII to reduction of PSI end acceptors). At Satakunta F(V)/F(M) and ΨEo in Betula pendula were higher in monocultures and lower in mixed plots, perhaps due to increasing light availability in mixed plots, which can induce photoinhibition. The opposite trend was observed in Picea abies, which was shaded in mixed plots. At Kaltenborn F(V)/F(M) decreased in Fagus sylvatica and P. abies in mixed plots due to competition both above- and belowground. At Satakunta LMA increased in B. pendula leaves with increasing species richness. Leaf area of ten leaves was reduced in F. sylvatica in mixed plots at Kaltenborn. By up-scaling the overall fluorescence response to plot level (PItot_plot ), a significant positive correlation with tree diversity was found at Kaltenborn, but not at Satakunta. This could suggest that competition/facilitation processes in mixed stands play a significant role in the early stages of forest establishment, but then tend to be compensated in more mature stands. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Segmented Poincaré plot analysis for risk stratification in patients with dilated cardiomyopathy.

PubMed

Voss, A; Fischer, C; Schroeder, R; Figulla, H R; Goernig, M

2010-01-01

The prognostic value of heart rate variability in patients with dilated cardiomyopathy (DCM) is limited and does not contribute to risk stratification although the dynamics of ventricular repolarization differs considerably between DCM patients and healthy subjects. Neither linear nor nonlinear methods of heart rate variability analysis could discriminate between patients at high and low risk for sudden cardiac death. The aim of this study was to analyze the suitability of the new developed segmented Poincaré plot analysis (SPPA) to enhance risk stratification in DCM. In contrast to the usual applied Poincaré plot analysis the SPPA retains nonlinear features from investigated beat-to-beat interval time series. Main features of SPPA are the rotation of cloud of points and their succeeded variability depended segmentation. Significant row and column probabilities were calculated from the segments and led to discrimination (up to p<0.005) between low and high risk in DCM patients. For the first time an index from Poincaré plot analysis of heart rate variability was able to contribute to risk stratification in patients suffering from DCM.

Temperature dependent current-voltage characteristics of Au/n-Si Schottky barrier diodes and the effect of transition metal oxides as an interface layer

NASA Astrophysics Data System (ADS)

Mahato, Somnath; Puigdollers, Joaquim

2018-02-01

Temperature dependent current-voltage (I‒V) characteristics of Au/n-type silicon (n-Si) Schottky barrier diodes have been investigated. Three transition metal oxides (TMO) are used as an interface layer between gold and silicon. The basic Schottky diode parameters such as ideality factor (n), barrier height (ϕb 0) and series resistance (Rs) are calculated and successfully explained by the thermionic emission (TE) theory. It has been found that ideality factor decreased and barrier height increased with increased of temperature. The conventional Richardson plot of ln(I0/T2) vs. 1000/T is determined the activation energy (Ea) and Richardson constant (A*). Whereas value of 'A*' is much smaller than the known theoretical value of n-type Si. The temperature dependent I-V characteristics obtained the mean value of barrier height (ϕb 0 bar) and standard deviation (σs) from the linear plot of ϕap vs. 1000/T. From the modified Richardson plot of ln(I0/T2) ˗ (qσ)2/2(kT)2 vs. 1000/T gives Richardson constant and homogeneous barrier height of Schottky diodes. Main observation in this present work is the barrier height and ideality factor shows a considerable change but the series resistance value exhibits negligible change due to TMO as an interface layer.