WorldWideScience

Sample records for net assimilation rate

  1. Increased Ratio of Electron Transport to Net Assimilation Rate Supports Elevated Isoprenoid Emission Rate in Eucalypts under Drought1[W][OPEN

    Science.gov (United States)

    Dani, Kaidala Ganesha Srikanta; Jamie, Ian McLeod; Prentice, Iain Colin; Atwell, Brian James

    2014-01-01

    Plants undergoing heat and low-CO2 stresses emit large amounts of volatile isoprenoids compared with those in stress-free conditions. One hypothesis posits that the balance between reducing power availability and its use in carbon assimilation determines constitutive isoprenoid emission rates in plants and potentially even their maximum emission capacity under brief periods of stress. To test this, we used abiotic stresses to manipulate the availability of reducing power. Specifically, we examined the effects of mild to severe drought on photosynthetic electron transport rate (ETR) and net carbon assimilation rate (NAR) and the relationship between estimated energy pools and constitutive volatile isoprenoid emission rates in two species of eucalypts: Eucalyptus occidentalis (drought tolerant) and Eucalyptus camaldulensis (drought sensitive). Isoprenoid emission rates were insensitive to mild drought, and the rates increased when the decline in NAR reached a certain species-specific threshold. ETR was sustained under drought and the ETR-NAR ratio increased, driving constitutive isoprenoid emission until severe drought caused carbon limitation of the methylerythritol phosphate pathway. The estimated residual reducing power unused for carbon assimilation, based on the energetic status model, significantly correlated with constitutive isoprenoid emission rates across gradients of drought (r2 > 0.8) and photorespiratory stress (r2 > 0.9). Carbon availability could critically limit emission rates under severe drought and photorespiratory stresses. Under most instances of moderate abiotic stress levels, increased isoprenoid emission rates compete with photorespiration for the residual reducing power not invested in carbon assimilation. A similar mechanism also explains the individual positive effects of low-CO2, heat, and drought stresses on isoprenoid emission. PMID:25139160

  2. Annual and Seasonal Mean Net Evaporation Rates of the Red Sea Water during Jan 1958 - Dec 2007

    OpenAIRE

    Nassir, Sahbaldeen Abdulaziz

    2012-01-01

    Data set including sea level, temperature, salinity, and current from Simple Ocean Data Assimilation (SODA) is used in this study to estimate the mean net annually and seasonally evaporation rates. Then wind data is used to examine its impact on the evaporation. This work calculated the seasonal and annual evaporation rates based on assumption of that there is no net mass transport (balanced). Hence, the difference in the transport supposed to be equal to the water that has eva...

  3. Effects of sulfur dioxide on net CO/sub 2/ assimilation in the lichen Evernia mesomorpha Nyl

    Energy Technology Data Exchange (ETDEWEB)

    Huebert, D B; L' Hirondelle, S J; Addison, P A

    1985-01-01

    Physiologically active thalli of the lichen Evernia mesomorpha Nyl. were very sensitive to short-term fumigations with low concentrations of gaseous sulfur dioxide. Net CO/sub 2/ assimilation rate (NAR) was significantly reduced after exposure to 0.085 ..mu..l l/sup -1/ (250 ..mu..g m/sup -3/) SO/sub 2/ for 1 h or more, and the reduction increased with increasing concentration. Duration of exposure had no significant effect on NAR, indicating the importance of rate of SO/sub 2/ uptake rather than the total amount absorbed. Respiration was significantly reduced after 4 h or more of exposure to 0.265 ..mu..l l/sup -1/ (639 ..mu..g m/sup -3/) SO/sub 2/ or higher. Recovery of NAR after fumigation was dependent on both SO/sub 2/ concentration and duration of fumigation, and on the time allowed for recovery. Virtually complete recovery occurred within 24 h after episodes with up to 0.355 ..mu..l l/sup -1/ (856 ..mu..g m/sup -3/) SO/sub 2/ for 1 h and 0.085 ..mu..l l/sup -1/ SO/sub 2/ for 4 h. Above these levels, recovery was incomplete or nonexistent after 24 h in clean air. The level of sensitivity found can be attributed to the environmental conditions during fumigation, which prevented thallus desiccation and inactivity. Based on this study, neither the concept of dose (concentration x time) nor that of threshold levels of SO/sub 2/ fumigations are supported. Peak exposures to SO/sub 2/ for short periods may be of primary importance in determining the survival of lichens in industrial areas.

  4. Annual variation in the net longshore sediment transport rate

    CSIR Research Space (South Africa)

    Schoonees, JS

    2000-05-01

    Full Text Available The annual variation in the net long shore sediment transport rates at three South African and at one North African site is investigated. The net rates at these sites, given in the first table, showed large variations. It was found that measurements...

  5. Net savings and the Japanese long-term interest rate

    NARCIS (Netherlands)

    Jansen, P.W.

    2011-01-01

    This article discusses why the interest rate on Japanese government bonds is so low in comparison with other industrialized countries with a better credit rating, after correcting for inflation differences. We find that the net savings surplus has kept the long-term interest rate low. Japanese

  6. Partitioning net ecosystem carbon exchange into net assimilation and respiration using 13CO2 measurements: A cost-effective sampling strategy

    Science.gov (United States)

    OgéE, J.; Peylin, P.; Ciais, P.; Bariac, T.; Brunet, Y.; Berbigier, P.; Roche, C.; Richard, P.; Bardoux, G.; Bonnefond, J.-M.

    2003-06-01

    The current emphasis on global climate studies has led the scientific community to set up a number of sites for measuring the long-term biosphere-atmosphere net CO2 exchange (net ecosystem exchange, NEE). Partitioning this flux into its elementary components, net assimilation (FA), and respiration (FR), remains necessary in order to get a better understanding of biosphere functioning and design better surface exchange models. Noting that FR and FA have different isotopic signatures, we evaluate the potential of isotopic 13CO2 measurements in the air (combined with CO2 flux and concentration measurements) to partition NEE into FR and FA on a routine basis. The study is conducted at a temperate coniferous forest where intensive isotopic measurements in air, soil, and biomass were performed in summer 1997. The multilayer soil-vegetation-atmosphere transfer model MuSICA is adapted to compute 13CO2 flux and concentration profiles. Using MuSICA as a "perfect" simulator and taking advantage of the very dense spatiotemporal resolution of the isotopic data set (341 flasks over a 24-hour period) enable us to test each hypothesis and estimate the performance of the method. The partitioning works better in midafternoon when isotopic disequilibrium is strong. With only 15 flasks, i.e., two 13CO2 nighttime profiles (to estimate the isotopic signature of FR) and five daytime measurements (to perform the partitioning) we get mean daily estimates of FR and FA that agree with the model within 15-20%. However, knowledge of the mesophyll conductance seems crucial and may be a limitation to the method.

  7. Effects of entrainment through Oconee Nuclear Station on carbon-14 assimilation rates of phytoplankton

    International Nuclear Information System (INIS)

    Kreh, T.V.; Derwort, J.E.

    1976-01-01

    Carbon assimilation rates of phytoplankton communities entrained through Oconee Nuclear Station were measured on six dates during 1974. Thermal, mechanical, condenser, and multiple entrainment effects on uptake rates were compared by incubating samples in vitro in controlled-temperature water baths. Duplicate light and dark bottles containing water from four cooling-system locations were exposed to temperatures approximating intake and discharge temperatures. The relationships were variable, but exposure of the hypolimnetic intake water at near-discharge temperatures (thermal effect) stimulated primary productivity in four of six experiments. Multiple entrainment and mechanical effects caused no consistent change in assimilation rates

  8. Rates of convergence of Brezier net over triangles

    International Nuclear Information System (INIS)

    Feng Yuyu.

    1986-12-01

    It is well known (Farin, 1979) that the sequence of Bezier nets f-circumflex n (x) associated with Bernstein-Bezier surface over a triangle converges to the surface uniformly as n goes to infinity. In this paper the precise rates of convergence are given. The pointwise convergence result and saturation theorem are presented. (author). 7 refs

  9. The Economics of Zero-Rating and Net Neutrality

    OpenAIRE

    Somogyi, Robert

    2016-01-01

    This paper studies zero-rating, an emerging business practice consisting in a mobile internet service provider (ISP) excluding the data generated by certain content providers (CPs) from its consumers' monthly data cap. Being at odds with the principle of net neutrality, these arrangements have recently attracted regulatory scrutiny all over the word. I analyze zero-rating incentives of a monopolistic ISP facing a capacity constraint in a two-sided market where consumption provides utility for...

  10. Modeling ionospheric pre-reversal enhancement and plasma bubble growth rate using data assimilation

    Science.gov (United States)

    Rajesh, P. K.; Lin, C. C. H.; Chen, C. H.; Matsuo, T.

    2017-12-01

    We report that assimilating total electron content (TEC) into a coupled thermosphere-ionosphere model by using the ensemble Kalman filter results in improved specification and forecast of eastward pre-reversal enhancement (PRE) electric field (E-field). Through data assimilation, the ionospheric plasma density, thermospheric winds, temperature and compositions are adjusted simultaneously. The improvement of dusk-side PRE E-field over the prior state is achieved primarily by intensification of eastward neutral wind. The improved E-field promotes a stronger plasma fountain and deepens the equatorial trough. As a result, the horizontal gradients of Pedersen conductivity and eastward wind are increased due to greater zonal electron density gradient and smaller ion drag at dusk, respectively. Such modifications provide preferable conditions and obtain a strengthened PRE magnitude closer to the observation. The adjustment of PRE E-field is enabled through self-consistent thermosphere and ionosphere coupling processes captured in the model. The assimilative outputs are further utilized to calculate the flux tube integrated Rayleigh-Taylor instability growth rate during March 2015 for investigation of global plasma bubble occurrence. Significant improvements in the calculated growth rates could be achieved because of the improved update of zonal electric field in the data assimilation forecast. The results suggest that realistic estimate or prediction of plasma bubble occurrence could be feasible by taking advantage of the data assimilation approach adopted in this work.

  11. Prediction of rate of CO2 assimilation of leaf lettuce under low light irradiation during storage

    International Nuclear Information System (INIS)

    Uchino, T.; Harada, F.; Hu, W.

    2003-01-01

    The rate of CO 2 assimilation of leaf lettuce changed with its respiration rate and gas constitution in a storage chamber. The optimum irradiance on the surface of leaf lettuce during storage using low light irradiation can be obtained by the prediction of the rate of CO 2 assimilation. For the above mentioned purpose the following equation were derived. -kd[C]/dt=0.5(1-f)I([C]-Γ/4.5[C]+10.5Γ)-ae -bt where, k: proportional constant (4.87×10 -3 mol⋅m -2 ) [C]: CO 2 concentration (ppm), t: time (h), f: fraction of light not absorbed by chloroplasts (0.23), I: irradiance (μmol⋅m-2⋅s -1 ), Γ: CO 2 compensation point without respiration (21.5ppm), a, b: parameters (0.308μmol⋅m -2 ⋅s -1 , 0.010h -1 ). Calculated values of rate of CO 2 assimilation by the equation agreed well with experimental ones at 3.4 and 6.5μmol⋅m -2 ⋅s -1 of irradiance, so it appeared that the assimilation rate could be sufficiently predicted

  12. Net reclassification index at event rate: properties and relationships.

    Science.gov (United States)

    Pencina, Michael J; Steyerberg, Ewout W; D'Agostino, Ralph B

    2017-12-10

    The net reclassification improvement (NRI) is an attractively simple summary measure quantifying improvement in performance because of addition of new risk marker(s) to a prediction model. Originally proposed for settings with well-established classification thresholds, it quickly extended into applications with no thresholds in common use. Here we aim to explore properties of the NRI at event rate. We express this NRI as a difference in performance measures for the new versus old model and show that the quantity underlying this difference is related to several global as well as decision analytic measures of model performance. It maximizes the relative utility (standardized net benefit) across all classification thresholds and can be viewed as the Kolmogorov-Smirnov distance between the distributions of risk among events and non-events. It can be expressed as a special case of the continuous NRI, measuring reclassification from the 'null' model with no predictors. It is also a criterion based on the value of information and quantifies the reduction in expected regret for a given regret function, casting the NRI at event rate as a measure of incremental reduction in expected regret. More generally, we find it informative to present plots of standardized net benefit/relative utility for the new versus old model across the domain of classification thresholds. Then, these plots can be summarized with their maximum values, and the increment in model performance can be described by the NRI at event rate. We provide theoretical examples and a clinical application on the evaluation of prognostic biomarkers for atrial fibrillation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. The effect of net foreign assets on saving rate

    Directory of Open Access Journals (Sweden)

    Ben David Nissim

    2014-01-01

    Full Text Available Observing empirical data we find that many countries try to delay the decision of increasing saving rate in order to avoid a decrease of the living standards. However the delay leads a deterioration of countries financial stability. We present a simple theoretical model that connects between countries' saving rate and their net foreign assets. Using cross section data set of 135 countries in 2010 we estimated the econometric relation between saving rate in 2010 as dependent variable and two explanatory variables: the current account in 2010 and the aggregated current account during 1980-2010. Our findings show that industrial countries in a bad financial state tend to decrease their saving rate as external debt is larger causing to deterioration in external debt while countries with good financial state tend to increase their saving rate and the tendency increase as financial state becomes better. Only in countries with a very large external debt saving rate tends to grow. The results point that gross foreign debt will keep increasing and will worsen world financial state causing increased risk of getting into a world crisis.

  14. Inferring CO2 Fluxes from OCO-2 for Assimilation into Land Surface Models to Calculate Net Ecosystem Exchange

    Science.gov (United States)

    Prouty, R.; Radov, A.; Halem, M.; Nearing, G. S.

    2016-12-01

    Investigations of mid to high latitude atmospheric CO2 show a growing seasonal amplitude. Land surface models poorly predict net ecosystem exchange (NEE) and are unable to substantiate these sporadic observations. An investigation of how the biosphere has reacted to changes in atmospheric CO2 is essential to our understanding of potential climate-vegetation feedbacks. A global, seasonal investigation of CO2-flux is then necessary in order to assimilate into land surface models for improving the prediction of annual NEE. The Atmospheric Radiation Measurement program (ARM) of DOE collects CO2-flux measurements (in addition to CO2 concentration and various other meteorological quantities) at several towers located around the globe at half hour temporal frequencies. CO2-fluxes are calculated via the eddy covariance technique, which utilizes CO2-densities and wind velocities to calculate CO2-fluxes. The global coverage of CO2 concentrations as provided by the Orbiting Carbon Observatory (OCO-2) provide satellite-derived CO2 concentrations all over the globe. A framework relating the satellite-inferred CO2 concentrations collocated with the ground-based ARM as well as Ameriflux stations would enable calculations of CO2-fluxes far from the station sites around the entire globe. Regression techniques utilizing deep-learning neural networks may provide such a framework. Additionally, meteorological reanalysis allows for the replacement of the ARM multivariable meteorological variables needed to infer the CO2-fluxes. We present the results of inferring CO2-fluxes from OCO-2 CO2 concentrations for a two year period, Sept. 2014- Sept. 2016 at the ARM station located near Oklahoma City. A feed-forward neural network (FFNN) is used to infer relationships between the following data sets: F([ARM CO2-density], [ARM Meteorological Data]) = [ARM CO2-Flux] F([OCO-2 CO2-density],[ARM Meteorological Data]) = [ARM CO2-Flux] F([ARM CO2-density],[Meteorological Reanalysis]) = [ARM CO2-Flux

  15. Comparison of net photosynthetic rate and 14C distribution between different cultural conditions on double cropping rice

    International Nuclear Information System (INIS)

    Huang Jianliang; Li Hesong; Zou Yingbin; Tu Naimei; Li Jianhui

    2002-01-01

    By applying the cultural method 'Vigorous Root-Strong Stem-Heavy Panicle Cultural Method' (VSHM), the yield of double cropping rice reached 18000 kg/hm 2 in large area at Liling county, Hunan province. The net photosynthetic rate and 14 C distribution of rice leaves between VSHM and traditional cultural methods (CK) were compared. The photosynthetic rate of the flag leaves at ripening stages under VSHM was higher than that of controls with both earlier rice or later rice. Regarding the net amount of 14 C-assimilate by a single flag leaf and the second top leaf, there were differences at the significant level of 0.01 and 0.05, respectively between VSHM and controls, and VSHM were 7.72%-35.05% higher. The percentage of distribution at panicles of 14 C-assimilate were 51.93%-61.40% when flag leaf was labelled, and 45.34%-54.25% when the second top leaf was labelled, that of earlier rice was higher than later rice respectively, but the differences were not significant between VSHM and CK. The actual yield of double cropping rice under the cultural condition of VSHM was 17710 kg/hm 2 , and increased by 18.33% when compared with controls

  16. Modeling whole-tree carbon assimilation rate using observed transpiration rates and needle sugar carbon isotope ratios.

    Science.gov (United States)

    Hu, Jia; Moore, David J P; Riveros-Iregui, Diego A; Burns, Sean P; Monson, Russell K

    2010-03-01

    *Understanding controls over plant-atmosphere CO(2) exchange is important for quantifying carbon budgets across a range of spatial and temporal scales. In this study, we used a simple approach to estimate whole-tree CO(2) assimilation rate (A(Tree)) in a subalpine forest ecosystem. *We analysed the carbon isotope ratio (delta(13)C) of extracted needle sugars and combined it with the daytime leaf-to-air vapor pressure deficit to estimate tree water-use efficiency (WUE). The estimated WUE was then combined with observations of tree transpiration rate (E) using sap flow techniques to estimate A(Tree). Estimates of A(Tree) for the three dominant tree species in the forest were combined with species distribution and tree size to estimate and gross primary productivity (GPP) using an ecosystem process model. *A sensitivity analysis showed that estimates of A(Tree) were more sensitive to dynamics in E than delta(13)C. At the ecosystem scale, the abundance of lodgepole pine trees influenced seasonal dynamics in GPP considerably more than Engelmann spruce and subalpine fir because of its greater sensitivity of E to seasonal climate variation. *The results provide the framework for a nondestructive method for estimating whole-tree carbon assimilation rate and ecosystem GPP over daily-to weekly time scales.

  17. Bowen ratio/energy balance technique for estimating crop net CO2 assimilation, and comparison with a canopy chamber

    Science.gov (United States)

    Held, A. A.; Steduto, P.; Orgaz, F.; Matista, A.; Hsiao, T. C.

    1990-12-01

    This paper describes a Bowen ratio/energy balance (BREB) system which, in conjunction with an infra-red gas analyzer (IRGA), is referred to as BREB+ and is used to estimate evapotranspiration ( ET) and net CO2 flux ( NCF) over crop canopies. The system is composed of a net radiometer, soil heat flux plates, two psychrometers based on platinum resistance thermometers (PRT), bridge circuits to measure resistances, an IRGA, air pumps and switching valves, and a data logger. The psychrometers are triple shielded and aspirated, and with aspiration also between the two inner shields. High resistance (1 000 ohm) PRT's are used for dry and wet bulbs to minimize errors due to wiring and connector resistances. A high (55 K ohm) fixed resistance serves as one arm of the resistance bridge to ensure linearity in output signals. To minimize gaps in data, to allow measurements at short (e.g., 5 min) intervals, and to simplify operation, the psychrometers were fixed at their upper and lower position over the crop and not alternated. Instead, the PRT's, connected to the bridge circuit and the data logger, were carefully calibrated together. Field tests using a common air source showed appartent effects of the local environment around each psychrometer on the temperatures measured. ET rates estimated with the BREB system were compared to those measured with large lysimeters. Daily totals agreed within 5%. There was a tendency, however, for the lysimeter measurements to lag behind the BREB measurements. Daily patterns of NCF estimated with the BREB+ system are consistent with expectations from theories and data in the literature. Side-by-side comparisons with a stirred Mylar canopy chamber showed similar NCF patterns. On the other hand, discrepancies between the results of the two methods were quite marked in the morning or afternoon on certain dates. Part of the discrepancies may be attributed to inaccuracies in the psychrometric temperature measurements. Other possible causes

  18. Studies on the dependence of fructification on the formation and translocation of assimilates in the broad bean (Vicia faba L. var. minor)

    International Nuclear Information System (INIS)

    Freye, E.; Schilling, G.

    1983-01-01

    Studies on the net CO 2 assimilation of growing pods in situ and the translocation of assimilates (application of 14 CO 2 ) from individual leaves have revealed that after flowering most of the assimilates (more than 70 %) are utilized by the fruits. Amputation of some pods resulted in a better supply of other organs of this kind, but not in an increased accumulation of 14 C in vegetative parts. The net CO 2 assimilation rate of the donor leaves was not influenced. Obviously, the sink capacity of the fruit was not fully used at normal supply with assimilates. As exposure of whole plants to CO 2 -enriched air (0.13 % by volume) strongly inhibited the early fall of pods, a lack of assimilates seems to be the main cause of weak fruit setting and thus low seed yield. The great yield variations of broad bean are likely to be attributed to the great dependence of its net assimilation rate on environment. (author)

  19. In-situ real time measurements of net erosion rates of copper during hydrogen plasma exposure

    Science.gov (United States)

    Kesler, Leigh; Wright, Graham; Peterson, Ethan; Whyte, Dennis

    2013-10-01

    In order to properly understand the dynamics of net erosion/deposition in fusion reactors, such as tokamaks, a diagnostic measuring the real time rates of net erosion/deposition during plasma exposure is necessary. The DIONISOS experiment produces real time measurements of net erosion/deposition by using Rutherford backscattering spectroscopy (RBS) ion beam analysis simultaneously with plasma exposure from a helicon plasma source. This in-situ method improves on ex-situ weight loss measurements by allowing measurement of possible synergistic effects of high ion implantation rates and net erosion rate and by giving a real time response to changes in plasma parameters. Previous work has validated this new technique for measuring copper (Cu) erosion from helium (He) plasma ion bombardment. This technique is now extended to measure copper erosion due to deuterium and hydrogen plasma ion exposure. Targets used were a 1.5 μm Cu layer on an aluminum substrate. Cu layer thickness is tracked in real time using 1.2 MeV proton RBS. Measured erosion rates will be compared to results from literature and He erosion rates. Supported by US DoE award DE-SC00-02060.

  20. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, BA; Langevoord, O; Bevan, RM; Engelaar, KR; Klaassen, M; Mulder, RJW

    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  1. Net capital flows to and the real exchange rate of Western Balkan countries

    Directory of Open Access Journals (Sweden)

    Gabrisch Hubert

    2015-01-01

    Full Text Available This paper uses Granger causality tests to assess the linkages between changes in the real exchange rate and net capital inflows using the example of Western Balkan countries, which have suffered from low competitiveness and external imbalances for many years. The real exchange rate is a measure of a country’s price competitiveness, and the paper uses two concepts: relative unit labour cost and relative inflation differential. The sample consists of six Western Balkan countries for the period 1996-2012, relative to the European Union (EU. The main finding is that changes in the net capital flows precede changes in relative unit labour costs and not vice versa. Also, there is evidence that net capital flows affect the inflation differential of countries, although to a less discernible extent. This suggests that the increasing divergence in the unit labour cost between the EU and Western Balkan countries up to the global financial crisis was at least partly the result of net capital inflows. The paper adds to the ongoing debate on improving cost competitiveness through wage restrictions as the main vehicle to avert the accumulation of current account imbalances. It shows the importance of changes in the exchange rate regime, reform of the interaction between the financial and the real sector, and financial supervision and structural change.

  2. The Influence of Herbivory on the net rate of Increase of Gypsy Moth Abundance: A Modeling Analysis

    Science.gov (United States)

     Harry T.  Valentine

    1983-01-01

    A differential equation model of gypsy moth abundance, average larval dry weight, and food abundance was used to analyze the effects of changes in foliar chemistry on the net per capita rate of increase in a gypsy moth population. If relative consumption rate per larva is unaffected by herbivory, a reduction in the nutritional value of foliage reduces the net rate of...

  3. Salinity and Salicylic Acid Interactions in Affecting Nitrogen Assimilation, Enzyme Activity, Ions Content and Translocation Rate of Maize Plants

    International Nuclear Information System (INIS)

    Khodary, S.E.A.; Moussa, H.R.

    2002-01-01

    This study was carried out to establish the relationship between nitrogen metabolism, enzyme activity, ions concentration as well as the translocation rate (TR) of carbohydrates and salicylic acid (SA) in salt-stressed maize (Zea mays L). Salicylic acid plus salinity treatment highly significantly increased: nucleic acids (DNA and RNA), protein content, phosphoenolpyruvate carboxylase (PEPCase) and nitrate reductase (NR) and inhibited nucleases (DNase and RNase) activities compared with Na CI-treated plants. In addition, the ionic levels of potassium (K), phosphorus (P), nitrate (NO 3 ) and the translocation rate of the labelled photo assimilates have also been stimulated while sodium (Na) ions content was decreased. It is concluded that, salinazid maize plants might show an enhancement in their growth pattern upon salicylic acid application

  4. Single interval longwave radiation scheme based on the net exchanged rate decomposition with bracketing

    Czech Academy of Sciences Publication Activity Database

    Geleyn, J.- F.; Mašek, Jan; Brožková, Radmila; Kuma, P.; Degrauwe, D.; Hello, G.; Pristov, N.

    2017-01-01

    Roč. 143, č. 704 (2017), s. 1313-1335 ISSN 0035-9009 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:86652079 Keywords : numerical weather prediction * climate models * clouds * parameterization * atmospheres * formulation * absorption * scattering * accurate * database * longwave radiative transfer * broadband approach * idealized optical paths * net exchanged rate decomposition * bracketing * selective intermittency Subject RIV: DG - Athmosphere Sciences, Meteorology OBOR OECD: Meteorology and atmospheric sciences Impact factor: 3.444, year: 2016

  5. Generation time, net reproductive rate, and growth in stage-age-structured populations

    DEFF Research Database (Denmark)

    Steiner, Uli; Tuljapurkar, Shripad; Coulson, Tim

    2014-01-01

    examples to show how reproductive timing Tc and level R0 are shaped by stage dynamics (individual trait changes), selection on the trait, and parent-offspring phenotypic correlation. We also show how population structure can affect dispersion in reproduction among ages and stages. These macroscopic...... to age-structured populations. Here we generalize this result to populations structured by stage and age by providing a new, unique measure of reproductive timing (Tc) that, along with net reproductive rate (R0), has a direct mathematical relationship to and approximates growth rate (r). We use simple...

  6. Tartronate semialdehyde reductase defines a novel rate-limiting step in assimilation and bioconversion of glycerol in Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Yanbin Liu

    Full Text Available BACKGROUND: Glycerol is a by-product of biodiesel production. Currently, it has limited applications with low bioconversion efficiency to most metabolites reported. This is partly attributed to the poor knowledge on the glycerol metabolic pathway in bacteria and fungi. METHODOLOGY/PRINCIPAL FINDINGS: We have established a fast screening method for identification of genes that improve glycerol utilization in Ustilago maydis. This was done by comparing the growth rates of T-DNA tagged mutant colonies on solid medium using glycerol as the sole carbon source. We present a detailed characterization of one of the mutants, GUM1, which contains a T-DNA element inserted into the promoter region of UM02592 locus (MIPS Ustilago maydis database, MUMDB, leading to enhanced and constitutive expression of its mRNA. We have demonstrated that um02592 encodes a functional tartronate semialdehyde reductase (Tsr1, which showed dual specificity to cofactors NAD(+ and NADP(+ and strong substrate specificity and enantioselectivity for D-glycerate. Improved glycerol assimilation in GUM1 was associated with elevated expression of tsr1 mRNA and this could be phenocopied by over-expression of the gene. Glycolipid accumulation was reduced by 45.2% in the knockout mutant whereas introduction of an extra copy of tsr1 driven by the glyceraldehyde phosphate dehydrogenase promoter increased it by 40.4%. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that tartronate semialdehyde reductase (TSR plays an important role in glycerol assimilation in U. maydis and defines a novel target in genetic engineering for improved conversion of glycerol to higher value products. Our results add significant depth to the understanding of the glycerol metabolic pathway in fungi. We have demonstrated, for the first time, a biological role of a eukaryotic TSR.

  7. Baseline Assessment of Net Calcium Carbonate Accretion Rates on U.S. Pacific Reefs.

    Science.gov (United States)

    Vargas-Ángel, Bernardo; Richards, Cristi L; Vroom, Peter S; Price, Nichole N; Schils, Tom; Young, Charles W; Smith, Jennifer; Johnson, Maggie D; Brainard, Russell E

    2015-01-01

    This paper presents a comprehensive quantitative baseline assessment of in situ net calcium carbonate accretion rates (g CaCO3 cm(-2) yr(-1)) of early successional recruitment communities on Calcification Accretion Unit (CAU) plates deployed on coral reefs at 78 discrete sites, across 11 islands in the central and south Pacific Oceans. Accretion rates varied substantially within and between islands, reef zones, levels of wave exposure, and island geomorphology. For forereef sites, mean accretion rates were the highest at Rose Atoll, Jarvis, and Swains Islands, and the lowest at Johnston Atoll and Tutuila. A comparison between reef zones showed higher accretion rates on forereefs compared to lagoon sites; mean accretion rates were also higher on windward than leeward sites but only for a subset of islands. High levels of spatial variability in net carbonate accretion rates reported herein draw attention to the heterogeneity of the community assemblages. Percent cover of key early successional taxa on CAU plates did not reflect that of the mature communities present on surrounding benthos, possibly due to the short deployment period (2 years) of the experimental units. Yet, net CaCO3 accretion rates were positively correlated with crustose coralline algae (CCA) percent cover on the surrounding benthos and on the CAU plates, which on average represented >70% of the accreted material. For foreeefs and lagoon sites combined CaCO3 accretion rates were statistically correlated with total alkalinity and Chlorophyll-a; a GAM analysis indicated that SiOH and Halimeda were the best predictor variables of accretion rates on lagoon sites, and total alkalinity and Chlorophyll-a for forereef sites, demonstrating the utility of CAUs as a tool to monitor changes in reef accretion rates as they relate to ocean acidification. This study underscores the pivotal role CCA play as a key benthic component and supporting actively calcifying reefs; high Mg-calcite exoskeletons makes CCA

  8. Baseline Assessment of Net Calcium Carbonate Accretion Rates on U.S. Pacific Reefs.

    Directory of Open Access Journals (Sweden)

    Bernardo Vargas-Ángel

    Full Text Available This paper presents a comprehensive quantitative baseline assessment of in situ net calcium carbonate accretion rates (g CaCO3 cm(-2 yr(-1 of early successional recruitment communities on Calcification Accretion Unit (CAU plates deployed on coral reefs at 78 discrete sites, across 11 islands in the central and south Pacific Oceans. Accretion rates varied substantially within and between islands, reef zones, levels of wave exposure, and island geomorphology. For forereef sites, mean accretion rates were the highest at Rose Atoll, Jarvis, and Swains Islands, and the lowest at Johnston Atoll and Tutuila. A comparison between reef zones showed higher accretion rates on forereefs compared to lagoon sites; mean accretion rates were also higher on windward than leeward sites but only for a subset of islands. High levels of spatial variability in net carbonate accretion rates reported herein draw attention to the heterogeneity of the community assemblages. Percent cover of key early successional taxa on CAU plates did not reflect that of the mature communities present on surrounding benthos, possibly due to the short deployment period (2 years of the experimental units. Yet, net CaCO3 accretion rates were positively correlated with crustose coralline algae (CCA percent cover on the surrounding benthos and on the CAU plates, which on average represented >70% of the accreted material. For foreeefs and lagoon sites combined CaCO3 accretion rates were statistically correlated with total alkalinity and Chlorophyll-a; a GAM analysis indicated that SiOH and Halimeda were the best predictor variables of accretion rates on lagoon sites, and total alkalinity and Chlorophyll-a for forereef sites, demonstrating the utility of CAUs as a tool to monitor changes in reef accretion rates as they relate to ocean acidification. This study underscores the pivotal role CCA play as a key benthic component and supporting actively calcifying reefs; high Mg-calcite exoskeletons

  9. Capture efficiency and injury rates of band-tailed pigeons using whoosh nets

    Science.gov (United States)

    Coxen, Christopher L.; Collins, Daniel P.; Carleton, Scott A.

    2018-01-01

    Catching ground feeding birds has typically been accomplished through small, walk-in funnel-style traps. This approach is limited because it requires a bird to find its way into the trap, is biased toward less wary birds, and does not allow targeted trapping of individual birds. As part of a large study on Band-tailed Pigeons (Patagioenas fasciata) in New Mexico, we needed a trapping method that would allow more control over the number of birds we could trap at one time, when a trap was deployed, and target trapping of specific individuals. We adopted a relatively novel trapping technique used primarily for shorebirds, whoosh nets, to trap Band-tailed Pigeons at 3 different sites where birds were being fed by local landowners. During 2013–2015, whoosh nets were used to trap 702 Band-tailed Pigeons at 3 different locations in New Mexico. We captured 12.54 ± 8.19 pigeons per shot over 56 capture events across 3 locations (range: 2–39). Some superficial injuries occurred using this technique and typically involved damage to the primary and secondary wing coverts. In 2013, 24% of captured birds had an injury of this nature, but after modifying the net speed, injury rates in 2014 and 2015 dropped to 8% and 7%, respectively. Recaptured previously injured birds showed new feather growth within 2 weeks and showed no signs of injury after 4 weeks. Whoosh nets proved to be a highly effective solution for trapping large numbers of pigeons at baited sites. These systems are easily transported, quickly deployed, and easily adapted to a variety of site conditions. 

  10. A New Approach for Mobile Advertising Click-Through Rate Estimation Based on Deep Belief Nets.

    Science.gov (United States)

    Chen, Jie-Hao; Zhao, Zi-Qian; Shi, Ji-Yun; Zhao, Chong

    2017-01-01

    In recent years, with the rapid development of mobile Internet and its business applications, mobile advertising Click-Through Rate (CTR) estimation has become a hot research direction in the field of computational advertising, which is used to achieve accurate advertisement delivery for the best benefits in the three-side game between media, advertisers, and audiences. Current research on the estimation of CTR mainly uses the methods and models of machine learning, such as linear model or recommendation algorithms. However, most of these methods are insufficient to extract the data features and cannot reflect the nonlinear relationship between different features. In order to solve these problems, we propose a new model based on Deep Belief Nets to predict the CTR of mobile advertising, which combines together the powerful data representation and feature extraction capability of Deep Belief Nets, with the advantage of simplicity of traditional Logistic Regression models. Based on the training dataset with the information of over 40 million mobile advertisements during a period of 10 days, our experiments show that our new model has better estimation accuracy than the classic Logistic Regression (LR) model by 5.57% and Support Vector Regression (SVR) model by 5.80%.

  11. A New Approach for Mobile Advertising Click-Through Rate Estimation Based on Deep Belief Nets

    Directory of Open Access Journals (Sweden)

    Jie-Hao Chen

    2017-01-01

    Full Text Available In recent years, with the rapid development of mobile Internet and its business applications, mobile advertising Click-Through Rate (CTR estimation has become a hot research direction in the field of computational advertising, which is used to achieve accurate advertisement delivery for the best benefits in the three-side game between media, advertisers, and audiences. Current research on the estimation of CTR mainly uses the methods and models of machine learning, such as linear model or recommendation algorithms. However, most of these methods are insufficient to extract the data features and cannot reflect the nonlinear relationship between different features. In order to solve these problems, we propose a new model based on Deep Belief Nets to predict the CTR of mobile advertising, which combines together the powerful data representation and feature extraction capability of Deep Belief Nets, with the advantage of simplicity of traditional Logistic Regression models. Based on the training dataset with the information of over 40 million mobile advertisements during a period of 10 days, our experiments show that our new model has better estimation accuracy than the classic Logistic Regression (LR model by 5.57% and Support Vector Regression (SVR model by 5.80%.

  12. A New Approach for Mobile Advertising Click-Through Rate Estimation Based on Deep Belief Nets

    Science.gov (United States)

    Zhao, Zi-Qian; Shi, Ji-Yun; Zhao, Chong

    2017-01-01

    In recent years, with the rapid development of mobile Internet and its business applications, mobile advertising Click-Through Rate (CTR) estimation has become a hot research direction in the field of computational advertising, which is used to achieve accurate advertisement delivery for the best benefits in the three-side game between media, advertisers, and audiences. Current research on the estimation of CTR mainly uses the methods and models of machine learning, such as linear model or recommendation algorithms. However, most of these methods are insufficient to extract the data features and cannot reflect the nonlinear relationship between different features. In order to solve these problems, we propose a new model based on Deep Belief Nets to predict the CTR of mobile advertising, which combines together the powerful data representation and feature extraction capability of Deep Belief Nets, with the advantage of simplicity of traditional Logistic Regression models. Based on the training dataset with the information of over 40 million mobile advertisements during a period of 10 days, our experiments show that our new model has better estimation accuracy than the classic Logistic Regression (LR) model by 5.57% and Support Vector Regression (SVR) model by 5.80%. PMID:29209363

  13. Effect on phloridzin on net rate of liquid absorption from the pleural space of rabbits.

    Science.gov (United States)

    Zocchi, L; Agostoni, E; Raffaini, A

    1996-11-01

    Previous indirect findings have suggested the occurrence of solute-coupled liquid absorption from the pleural space, consistent with Na(+)-K(+)-ATPase on the interstitial side plus a Na(+)-H+ and CI(-)-HCO3- double exchange on the luminal side of the pleural mesothelium. To assess whether Na(+)-glucose cotransport also operates on the luminal side, the relationship between net rate of liquid absorption from the right pleural space (Jnet) and volume of liquid injected into this space (0.5, 1 or 2 ml) was determined in anaesthetized rabbits during hydrothoraces with phloridzin (10(-3)M) or with phloridzin plus 4-acetamido-4'-isothiocyanatostilbene-2, 2'-disulphonic acid (SITS; 1.5 x 10(-4)M). The relationship obtained during hydrothoraces with phloridzin was displaced downwards by 0.09 ml h-1 relative to that in control hydrothoraces (P pleural mesothelium, operating simultaneously with the double exchange also under physiological conditions.

  14. The impact of rate design and net metering on the bill savings from distributed PV for residential customers in California

    International Nuclear Information System (INIS)

    Darghouth, Naim R.; Barbose, Galen; Wiser, Ryan

    2011-01-01

    Net metering has become a widespread mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), but has faced challenges as PV installations grow to a larger share of generation in a number of states. This paper examines the value of the bill savings that customers receive under net metering, and the associated role of retail rate design, based on a sample of approximately two hundred residential customers of California's two largest electric utilities. We find that the bill savings per kWh of PV electricity generated varies by more than a factor of four across the customers in the sample, which is largely attributable to the inclining block structure of the utilities' residential retail rates. We also compare the bill savings under net metering to that received under three potential alternative compensation mechanisms, based on California's Market Price Referent (MPR). We find that net metering provides significantly greater bill savings than a full MPR-based feed-in tariff, but only modestly greater savings than alternative mechanisms under which hourly or monthly net excess generation is compensated at the MPR rate. - Highlights: → We examine the value of bill savings under net metering to PV owners in California. → Bill savings per kWh of PV generation varies by a factor of four with net metering. The variation is attributable to rate design, the unique inclining block structure. → The median value of bill savings is reduced by 40-67% with MPR feed-in tariff. → The median value of bill savings is reduced by 6-12% with hourly netting.

  15. Size and growth rate differences of larval Baltic sprat Sprattus sprattus collected with bongo and MIK nets.

    Science.gov (United States)

    Fey, D P

    2015-01-01

    The effect of sampling with bongo (0·6 m diameter frame with 500 µm mesh) and Methot Isaac Kidd (MIK) (2 m diameter frame with 2 mm mesh finished with 500 µm codend) nets on standard length (LS ) range and growth rate differences was tested for larval Sprattus sprattus (n = 906, LS range: 7·0-34·5 mm) collected during four cruises in the summer months of 2006, 2007, 2009 and 2010 in the southern Baltic Sea. Although the minimum size of larvae collected with the bongo and MIK nets was similar in each cruise (from c. 7 to 9 mm), the MIK nets permitted collecting larger specimens (up to c. 34 mm) than the bongo nets did (up to c. 27 mm). The growth rates of larvae collected with the bongo and MIK nets (specimens of the same size range were compared for three cruises) were not statistically different (mean = 0·55 mm day(-1) , n = 788, LS range: 7·0-27·4 mm), which means the material collected with these two nets can be combined and growth rate results between them were compared. © 2014 The Fisheries Society of the British Isles.

  16. Influence of Subjectivity in Geological Mapping on the Net Penetration Rate Prediction for a Hard Rock TBM

    Science.gov (United States)

    Seo, Yongbeom; Macias, Francisco Javier; Jakobsen, Pål Drevland; Bruland, Amund

    2018-05-01

    The net penetration rate of hard rock tunnel boring machines (TBM) is influenced by rock mass degree of fracturing. This influence is taken into account in the NTNU prediction model by the rock mass fracturing factor ( k s). k s is evaluated by geological mapping, the measurement of the orientation of fractures and the spacing of fractures and fracture type. Geological mapping is a subjective procedure. Mapping results can therefore contain considerable uncertainty. The mapping data of a tunnel mapped by three researchers were compared, and the influence of the variation in geological mapping was estimated to assess the influence of subjectivity in geological mapping. This study compares predicted net penetration rates and actual net penetration rates for TBM tunneling (from field data) and suggests mapping methods that can reduce the error related to subjectivity. The main findings of this paper are as follows: (1) variation of mapping data between individuals; (2) effect of observed variation on uncertainty in predicted net penetration rates; (3) influence of mapping methods on the difference between predicted and actual net penetration rate.

  17. Net herbage accumulation rate and crude protein content of Urochloa brizantha cultivars under shade intensities

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Lima Meirelles

    2013-12-01

    Full Text Available The use of silvopastoral systems is a sustainable alternative for animal production in various regions of the Brazil. However to obtain satisfactory results in these systems, the selection of forage species that grows well in the shade should be done. The tolerance of plants to light restriction and the correctly choice of species, considering good nutritional values for these conditions has great importance. The study of artificial shading for forage production helps the clarification of issues related to the behavior of plants under reduced light prior to use in integrations with forests. The aim of the study was to evaluate the net herbage accumulation rate of forage (HAR and crude protein (CP of Urochloa brizantha cultivars (Marandu and Piatã under natural light and shading of 30 and 60%. The experiment was conducted at FMVZ - UNESP, Botucatu. The experimental design was a randomized block in factorial arrangement 3 x 2 (three shading levels: 0, 30 and 60%, two cultivars: Marandu and Piatã with three replications and repeated measures (3 cuts. Sample collection occurred when the cultivars reached 35 cm in height. The treatments with shading showed lower cutting intervals as compared to those subjected to full sunlight, because they have reached in a shorter time to time as determined cut-off criterion (mean of 37, 45 and 61 days for reduction of 60%, reduction of 30% and full sun. Significant effects (P<0.05 interaction cultivar x shade x cut on the net herbage accumulation rate (HAR. Most HAR (P<0.05 was observed for cv. Marandu 60% reduction in lightness (127 kg/ha/day due to increased production of stem during the first growing cycle. The lower HAR also occurred to Marandu, but under natural light in the third cut (34 kg/ha/day due to adverse weather conditions during the growth interval. The shadow effect and the cutting (P<0.05 affected CP. The percentage of CP on cultivars showed the highest values (average value of 9.27% in 60

  18. [Effects of reduced solar radiation on winter wheat flag leaf net photosynthetic rate].

    Science.gov (United States)

    Zheng, You-Fei; Ni, Yan-Li; Mai, Bo-Ru; Wu, Rong-Jun; Feng, Yan; Sun, Jian; Li, Jian; Xu, Jing-Xin

    2011-06-01

    Taking winter wheat Triticum aestivum L. (cv. Yangmai 13) as test material, a field experiment was conducted in Nanjing City to study the effects of simulated reduced solar radiation on the diurnal variation of winter wheat flag leaf photosynthetic rate and the main affecting factors. Five treatments were installed, i. e., 15% (T15), 20% (T20) , 40% (T40), 60% (T60), and 100% (CK) of total incident solar radiation. Reduced solar irradiance increased the chlorophyll and lutein contents significantly, but decreased the net photosynthetic rate (Pn). Under different solar irradiance, the diurnal variation of Pn had greater difference, and the daily maximum Pn was in the order of CK > T60 > T40 > T 20 > T15. In CK, the Pn exhibited a double peak diurnal curve; while in the other four treatments, the Pn showed a single peak curve, and the peak was lagged behind that of CK. Correlation analysis showed that reduced solar irradiance was the main factor affecting the diurnal variation of Pn, but the physiological parameters also played important roles in determining the diurnal variation of Pn. In treatments T60 and T40, the photosynthesis active radiation (PAR), leaf temperature (T1) , stomatal conductance (Gs) , and transpiration rate (Tr) were significantly positively correlated with Pn, suggesting their positive effects on Pn. The intercellular CO2 concentration (Ci) and stomatal limitation (Ls) had significant negative correlations with Pn in treatments T60 and T40 but significant positive correlations with Pn in treatments T20 and T15, implying that the Ci and Ls had negative (or positive) effects on Pn when the solar irradiance was higher (or lower) than 40% of incident solar irradiance.

  19. Steady-state room temperature fluorescence and CO/sub 2/ assimilation rates in intact leaves. [Phaseolus vulgaris; Xanthium strumarium

    Energy Technology Data Exchange (ETDEWEB)

    Sharkey, T D

    1985-01-01

    Steady-state room temperature variable fluorescence from leaves was measured as a function of CO/sub 2/ pressure in Xanthium strumarium L. and Phaseolus vulgaris L. Measurements were made in a range of light intensities, at normal and low O/sub 2/ partial pressure and over a range of temperatures. At low CO/sub 2/ pressure fluorescence increased with increasing CO/sub 2/. At higher CO/sub 2/ pressure fluorescence usually decreased with increasing CO/sub 2/ but occasionally increased slightly. The transition CO/sub 2/ pressure between the responses could be changed by changing light, O/sub 2/ pressure, or temperature. This breakpoint in the fluorescence-CO/sub 2/ curve was a reliable indicator of the transition between ribulose 1,5-bisphosphate (RuBP) saturated assimilation and RuBP regeneration limited assimilation. The fluorescence signal was not a reliable indicator of O/sub 2/-insensitive assimilation in these C/sub 3/ species. 21 references, 8 figures.

  20. Data filtering and expected muon and neutrino event rates in the KM3NeT neutrino telescope

    Energy Technology Data Exchange (ETDEWEB)

    Shanidze, Rezo [ECAP, University of Erlangen-Nuremberg, Erwin-Rommel-Str.1, 91058 Erlangen (Germany); Collaboration: ANTARES-KM3NeT-Erlangen-Collaboration

    2011-07-01

    KM3NeT is a future Mediterranean deep sea neutrino telescope with an instrumented volume of several cubic kilometres. The neutrino and muon events in KM3NeT will be reconstructed from the signals collected from the telescope's photo detectors. However, in the deep sea the dominant source of photon signals are the decays of K40 nuclei and bioluminescence. The selection of neutrino and muon events requires the implementation of fast and efficient data filtering algorithms for the reduction of accidental background event rates. Possible data filtering and triggering schemes for the KM3NeT neutrino telescope and expected muon and neutrino event rates are discussed.

  1. Net sputtering rate due to hot ions in a Ne-Xe discharge gas bombarding an MgO layer

    International Nuclear Information System (INIS)

    Ho, S.; Tamakoshi, T.; Ikeda, M.; Mikami, Y.; Suzuki, K.

    2011-01-01

    An analytical method is developed for determining net sputtering rate for an MgO layer under hot ions with low energy ( h i , above a threshold energy of sputtering, E th,i , multiplied by a yield coefficient. The threshold energy of sputtering is determined from dissociation energy required to remove an atom from MgO surface multiplied by an energy-transfer coefficient. The re-deposition rate of the sputtered atoms is calculated by a diffusion simulation using a hybridized probabilistic and analytical method. These calculation methods are combined to analyze the net sputtering rate. Maximum net sputtering rate due to the hot neon ions increases above the partial pressure of 4% xenon as E h Ne becomes higher and decreases near the partial pressure of 20% xenon as ion flux of neon decreases. The dependence due to the hot neon ions on partial pressure and applied voltage agrees well with experimental results, but the dependence due to the hot xenon ions deviates considerably. This result shows that the net sputtering rate is dominated by the hot neon ions. Maximum E h Ne (E h Ne,max = 5.3 - 10.3 eV) is lower than E th,Ne (19.5 eV) for the MgO layer; therefore, weak sputtering due to the hot neon ions takes place. One hot neon ion sputters each magnesium and each oxygen atom on the surface and distorts around a vacancy. The ratio of the maximum net sputtering rate is approximately determined by number of the ions at E h i,max multiplied by an exponential factor of -E th,i /E h i,max .

  2. Low inflation, a high net savings surplus and institutional restrictions keep the Japanese long-term interest rate low

    NARCIS (Netherlands)

    Jansen, Pieter W.

    2006-01-01

    This paper explains that the interest rate on long-term Japanese government bonds is low in comparison with other industrialised countries for four main reasons: lower inflation, net savings surplus, institutional restrictions and home bias. Monetary policy and institutionalised purchases of

  3. Net Metering and Market Feedback Loops: Exploring the Impact of Retail Rate Design on Distributed PV Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Darghouth, Naïm R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-13

    The substantial increase in deployment of customer-sited solar photovoltaics (PV) in the United States has been driven by a combination of steeply declining costs, financing innovations, and supportive policies. Among those supportive policies is net metering, which in most states effectively allows customers to receive compensation for distributed PV generation at the full retail electricity price. The current design of retail electricity rates and the presence of net metering have elicited concerns that the possible under-recovery of fixed utility costs from PV system owners may lead to a feedback loop of increasing retail prices that accelerate PV adoption and further rate increases. However, a separate and opposing feedback loop could offset this effect: increased PV deployment may lead to a shift in the timing of peak-period electricity prices that could reduce the bill savings received under net metering where time-varying retail electricity rates are used, thereby dampening further PV adoption. In this paper, we examine the impacts of these two competing feedback dynamics on U.S. distributed PV deployment through 2050 for both residential and commercial customers, across states. Our results indicate that, at the aggregate national level, the two feedback effects nearly offset one another and therefore produce a modest net effect, although their magnitude and direction vary by customer segment and by state. We also model aggregate PV deployment trends under various rate designs and net-metering rules, accounting for feedback dynamics. Our results demonstrate that future adoption of distributed PV is highly sensitive to retail rate structures. Whereas flat, time-invariant rates with net metering lead to higher aggregate national deployment levels than the current mix of rate structures (+5% in 2050), rate structures with higher monthly fixed customer charges or PV compensation at levels lower than the full retail rate can dramatically erode aggregate customer

  4. Gill net selectivity and catch rates of pelagic fish in tropical coastal ...

    African Journals Online (AJOL)

    The fish species and size selectivity of gillnets design with monofilament nylon polyethylene netting materials were investigated in Lagos Lagoon, Nigeria between September and December 2005. The gillnets floats and sinkers were improvised from rubber slippers and lead metallic objects which were attached at intervals ...

  5. Trends in readmission rates for safety net hospitals and non-safety net hospitals in the era of the US Hospital Readmission Reduction Program: a retrospective time series analysis using Medicare administrative claims data from 2008 to 2015.

    Science.gov (United States)

    Salerno, Amy M; Horwitz, Leora I; Kwon, Ji Young; Herrin, Jeph; Grady, Jacqueline N; Lin, Zhenqiu; Ross, Joseph S; Bernheim, Susannah M

    2017-07-13

    To compare trends in readmission rates among safety net and non-safety net hospitals under the US Hospital Readmission Reduction Program (HRRP). A retrospective time series analysis using Medicare administrative claims data from January 2008 to June 2015. We examined 3254 US hospitals eligible for penalties under the HRRP, categorised as safety net or non-safety net hospitals based on the hospital's proportion of patients with low socioeconomic status. Admissions for Medicare fee-for-service patients, age ≥65 years, discharged alive, who had a valid five-digit zip code and did not have a principal discharge diagnosis of cancer or psychiatric illness were included, for a total of 52 516 213 index admissions. Mean hospital-level, all-condition, 30-day risk-adjusted standardised unplanned readmission rate, measured quarterly, along with quarterly rate of change, and an interrupted time series examining: April-June 2010, after HRRP was passed, and October-December 2012, after HRRP penalties were implemented. 58.0% (SD 15.3) of safety net hospitals and 17.1% (SD 10.4) of non-safety net hospitals' patients were in the lowest quartile of socioeconomic status. The mean safety net hospital standardised readmission rate declined from 17.0% (SD 3.7) to 13.6% (SD 3.6), whereas the mean non-safety net hospital declined from 15.4% (SD 3.0) to 12.7% (SD 2.5). The absolute difference in rates between safety net and non-safety net hospitals declined from 1.6% (95% CI 1.3 to 1.9) to 0.9% (0.7 to 1.2). The quarterly decline in standardised readmission rates was 0.03 percentage points (95% CI 0.03 to 0.02, preadmission rates for safety net hospitals have decreased more rapidly than those for non-safety net hospitals. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Variability of filtration and food assimilation rates, respiratory activity and multixenobiotic resistance (MXR mechanism in the mussel Perna perna under lead influence

    Directory of Open Access Journals (Sweden)

    M. L. PESSATTI

    Full Text Available The economic importance that myticulture is conquering in Santa Catarina State (South of Brazil explains the crescent search for new coastal sites for farming. Physiological and biochemical studies of the mussel Perna perna are important to the establishment of methodologies for program assessment and environmental monitoring, allowing to infer about site quality and possible influences of xenobiotic agents on coastal areas. In order to evaluate effects caused by lead poisoning (1.21 mumol.L-1, the mussels were maintained at constant temperature (25ºC and fed with Chaetoceros gracilis for 15 days. The control group was acclimatized in sea water 30‰. At the end of this period time, physiological measurements were carried out along with statistic analysis for filtration rates, lead assimilation and overall respiratory activity. The mechanism of multixenobiotic resistance (MXR was particularly evaluated in standardized gill fragments using rhodamine B accumulation and its quantification under fluorescence optical microscopy. Regarding the control group, results had shown that the mussels maintenance in a lead-poisoned environment caused higher filtration rates (1.04 and 2.3 and L.h-1.g-1; p < 0.05 and lower assimilation rates (71.96% and 54.1%, respectively. Also it was confirmed a lesser rhodamine B accumulation in the assays under influence of lead, suggesting that this metal induces the MXR mechanism expression in mussel P. perna. These results indicate that such physiological and biochemical alterations in the mussels can modify the energy fluxes of its metabolism, resulting in possible problems on the coastal systems used as cultivating sites.

  7. Variability of filtration and food assimilation rates, respiratory activity and multixenobiotic resistance (MXR mechanism in the mussel Perna perna under lead influence

    Directory of Open Access Journals (Sweden)

    PESSATTI M. L.

    2002-01-01

    Full Text Available The economic importance that myticulture is conquering in Santa Catarina State (South of Brazil explains the crescent search for new coastal sites for farming. Physiological and biochemical studies of the mussel Perna perna are important to the establishment of methodologies for program assessment and environmental monitoring, allowing to infer about site quality and possible influences of xenobiotic agents on coastal areas. In order to evaluate effects caused by lead poisoning (1.21 mumol.L-1, the mussels were maintained at constant temperature (25ºC and fed with Chaetoceros gracilis for 15 days. The control group was acclimatized in sea water 30?. At the end of this period time, physiological measurements were carried out along with statistic analysis for filtration rates, lead assimilation and overall respiratory activity. The mechanism of multixenobiotic resistance (MXR was particularly evaluated in standardized gill fragments using rhodamine B accumulation and its quantification under fluorescence optical microscopy. Regarding the control group, results had shown that the mussels maintenance in a lead-poisoned environment caused higher filtration rates (1.04 and 2.3 and L.h-1.g-1; p < 0.05 and lower assimilation rates (71.96% and 54.1%, respectively. Also it was confirmed a lesser rhodamine B accumulation in the assays under influence of lead, suggesting that this metal induces the MXR mechanism expression in mussel P. perna. These results indicate that such physiological and biochemical alterations in the mussels can modify the energy fluxes of its metabolism, resulting in possible problems on the coastal systems used as cultivating sites.

  8. Assimilation of carbon and transport of assimilates in coniferous trees under the influence of airborne pollutants. Photosynthesis rate and assimilate distribution in young fir trees (Picea abies [L.]Karst.) under controlled exposure to ozone. Final report; Assimilation von Kohlenstoff und der Assimilattransport in Coniferen unter dem Einfluss von Luftschadstoffen. Photosyntheseleistung und Assimilatverteilung in jungen Fichten (Picea abies [L.]Karst.) unter kontrollierter Ozon-Exposition. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Willenbrink, J.; Schatten, T.

    1992-12-31

    In this project, effects of long-term, low-level ozone exposure on CO{sub 2}fixation and assimilate partitioning in 4-years spruces old were studied. 1. In October, ozone exposure resulted in a 40% decrease of photosynthesis. Chlorophyll content was not altered. Depression of net photosynthesis by ozone exposure fluctuates. At least partly, this depression of net photosynthesis might reflect an increase of respiration. After 6 weeks of ozone exposure, both stomatal conductivity and transpiration seemed to be lowered. However, internal [CO{sub 2}] and water use efficiency were not significantly altered. 2. Compared with the control, needles of ozone-exposed plants exhibited a shift of the {sup 14}C-ratio of {beta}-carotene/xanthophylls which effect faded away with the season (October). 3. In August and October, translocation of {sup 14}C-assimilates from the {sup 14}C-fed source leaves seems to be impeded by ozone exposure. 4. No O{sub 3}-related differences were found for the lipophilic as well as for the fractions of organic or amino acids. For the sink tissues (twig, stem, root), less label was found in non-starch residue in August (main growth season), in O{sub 3}-exposed plants. 5. Starch and sugar content of cortex, cambium, xylem, and of the root follow annual cycles. Under ozon exposure, levels of {sup 14}C-starch and {sup 14}C-sucrose are lowered whereas in the needles, build-up of {sup 14}C-starch was detected. 6. Obviously, long-term low-level ozone affects allocation of assimilates. Secondary effects on chloroplasts by the treatment cannot be excluded. (orig./UWA) [Deutsch] Unter Labor- bzw. Gewaechshausbedingungen wurde der Einfluss einer kontrollierten Ozonexposition auf die Photosyntheseleistung und die Assimilatverteilung in 4-jaehrigen Fichten untersucht. 1. Unter Ozon-Exposition wird die Netto-Photosyntheserate in den jungen Nadeln zum Herbst hin reduziert, waehrend der Chlorophyllgehalt unbeeinflusst bleibt. Die Photosyntheserate der jungen Nadeln

  9. A Configurable Event-Driven Convolutional Node with Rate Saturation Mechanism for Modular ConvNet Systems Implementation

    Science.gov (United States)

    Camuñas-Mesa, Luis A.; Domínguez-Cordero, Yaisel L.; Linares-Barranco, Alejandro; Serrano-Gotarredona, Teresa; Linares-Barranco, Bernabé

    2018-01-01

    Convolutional Neural Networks (ConvNets) are a particular type of neural network often used for many applications like image recognition, video analysis or natural language processing. They are inspired by the human brain, following a specific organization of the connectivity pattern between layers of neurons known as receptive field. These networks have been traditionally implemented in software, but they are becoming more computationally expensive as they scale up, having limitations for real-time processing of high-speed stimuli. On the other hand, hardware implementations show difficulties to be used for different applications, due to their reduced flexibility. In this paper, we propose a fully configurable event-driven convolutional node with rate saturation mechanism that can be used to implement arbitrary ConvNets on FPGAs. This node includes a convolutional processing unit and a routing element which allows to build large 2D arrays where any multilayer structure can be implemented. The rate saturation mechanism emulates the refractory behavior in biological neurons, guaranteeing a minimum separation in time between consecutive events. A 4-layer ConvNet with 22 convolutional nodes trained for poker card symbol recognition has been implemented in a Spartan6 FPGA. This network has been tested with a stimulus where 40 poker cards were observed by a Dynamic Vision Sensor (DVS) in 1 s time. Different slow-down factors were applied to characterize the behavior of the system for high speed processing. For slow stimulus play-back, a 96% recognition rate is obtained with a power consumption of 0.85 mW. At maximum play-back speed, a traffic control mechanism downsamples the input stimulus, obtaining a recognition rate above 63% when less than 20% of the input events are processed, demonstrating the robustness of the network. PMID:29515349

  10. A Configurable Event-Driven Convolutional Node with Rate Saturation Mechanism for Modular ConvNet Systems Implementation

    Directory of Open Access Journals (Sweden)

    Luis A. Camuñas-Mesa

    2018-02-01

    Full Text Available Convolutional Neural Networks (ConvNets are a particular type of neural network often used for many applications like image recognition, video analysis or natural language processing. They are inspired by the human brain, following a specific organization of the connectivity pattern between layers of neurons known as receptive field. These networks have been traditionally implemented in software, but they are becoming more computationally expensive as they scale up, having limitations for real-time processing of high-speed stimuli. On the other hand, hardware implementations show difficulties to be used for different applications, due to their reduced flexibility. In this paper, we propose a fully configurable event-driven convolutional node with rate saturation mechanism that can be used to implement arbitrary ConvNets on FPGAs. This node includes a convolutional processing unit and a routing element which allows to build large 2D arrays where any multilayer structure can be implemented. The rate saturation mechanism emulates the refractory behavior in biological neurons, guaranteeing a minimum separation in time between consecutive events. A 4-layer ConvNet with 22 convolutional nodes trained for poker card symbol recognition has been implemented in a Spartan6 FPGA. This network has been tested with a stimulus where 40 poker cards were observed by a Dynamic Vision Sensor (DVS in 1 s time. Different slow-down factors were applied to characterize the behavior of the system for high speed processing. For slow stimulus play-back, a 96% recognition rate is obtained with a power consumption of 0.85 mW. At maximum play-back speed, a traffic control mechanism downsamples the input stimulus, obtaining a recognition rate above 63% when less than 20% of the input events are processed, demonstrating the robustness of the network.

  11. A Configurable Event-Driven Convolutional Node with Rate Saturation Mechanism for Modular ConvNet Systems Implementation.

    Science.gov (United States)

    Camuñas-Mesa, Luis A; Domínguez-Cordero, Yaisel L; Linares-Barranco, Alejandro; Serrano-Gotarredona, Teresa; Linares-Barranco, Bernabé

    2018-01-01

    Convolutional Neural Networks (ConvNets) are a particular type of neural network often used for many applications like image recognition, video analysis or natural language processing. They are inspired by the human brain, following a specific organization of the connectivity pattern between layers of neurons known as receptive field. These networks have been traditionally implemented in software, but they are becoming more computationally expensive as they scale up, having limitations for real-time processing of high-speed stimuli. On the other hand, hardware implementations show difficulties to be used for different applications, due to their reduced flexibility. In this paper, we propose a fully configurable event-driven convolutional node with rate saturation mechanism that can be used to implement arbitrary ConvNets on FPGAs. This node includes a convolutional processing unit and a routing element which allows to build large 2D arrays where any multilayer structure can be implemented. The rate saturation mechanism emulates the refractory behavior in biological neurons, guaranteeing a minimum separation in time between consecutive events. A 4-layer ConvNet with 22 convolutional nodes trained for poker card symbol recognition has been implemented in a Spartan6 FPGA. This network has been tested with a stimulus where 40 poker cards were observed by a Dynamic Vision Sensor (DVS) in 1 s time. Different slow-down factors were applied to characterize the behavior of the system for high speed processing. For slow stimulus play-back, a 96% recognition rate is obtained with a power consumption of 0.85 mW. At maximum play-back speed, a traffic control mechanism downsamples the input stimulus, obtaining a recognition rate above 63% when less than 20% of the input events are processed, demonstrating the robustness of the network.

  12. Magnetic sheath effect on the gross and net erosion rates due to impurities

    Science.gov (United States)

    Mellet, N.; Pégourié, B.; Martin, C.; Gunn, J. P.; Bufferand, H.; Roubin, P.

    2016-02-01

    Simulations of impurity trajectories in deuterium plasmas in the vicinity of the surface are performed by taking into account the magnetic sheath in conditions relevant for ITER and WEST. We show that the magnetic sheath has a strong effect on the average impact angle of impurities in divertor conditions and that it can lead to an increase of ≈ 60% at the gross erosion maximum for neon (Ne+4) compared to the case when only the cyclotron motion is considered. The evaluation of the net erosion has been undertaken by retaining local redeposition of tungsten (W). We investigate how it is affected by the sheath magnetic potential profile. The largest effect is however observed when an energy distribution is considered. In this case the number of particles that manage to exit the sheath is larger as it is dominated by the more energetic particles. The comparison with other work is also discussed. The application to a scenario of the WEST project is finally performed, which exhibits a moderate, however non negligible, erosion of the plasma facing components.

  13. Methods for measuring specific rates of mercury methylation and degradation and their use in determining factors controlling net rates of mercury methylation

    International Nuclear Information System (INIS)

    Ramlal, P.S.; Rudd, J.W.M.; Hecky, R.E.

    1986-01-01

    A method was developed to estimate specific rates of demethylation of methyl mercury in aquatic samples by measuring the volatile 14 C end products of 14 CH 3 HgI demethylation. This method was used in conjuction with a 203 Hg 2+ radiochemical method which determines specific rates of mercury methylation. Together, these methods enabled us to examine some factors controlling the net rate of mercury methylation. The methodologies were field tested, using lake sediment samples from a recently flooded reservoir in the Southern Indian Lake system which had developed a mercury contamination problem in fish. Ratios of the specific rates of methylation/demethylation were calculated. The highest ratios of methylation/demethylation were calculated. The highest ratios of methylation/demethylation occurred in the flooded shorelines of Southern Indian Lake. These results provide an explanation for the observed increases in the methyl mercury concentrations in fish after flooding

  14. A New Approach for Mobile Advertising Click-Through Rate Estimation Based on Deep Belief Nets

    OpenAIRE

    Chen, Jie-Hao; Zhao, Zi-Qian; Shi, Ji-Yun; Zhao, Chong

    2017-01-01

    In recent years, with the rapid development of mobile Internet and its business applications, mobile advertising Click-Through Rate (CTR) estimation has become a hot research direction in the field of computational advertising, which is used to achieve accurate advertisement delivery for the best benefits in the three-side game between media, advertisers, and audiences. Current research on the estimation of CTR mainly uses the methods and models of machine learning, such as linear model or re...

  15. EFFECT OF GIVING MIXED INSECTICIDE CARBOFURAN IN COW FECES TOWARDS CONSUMPTION RATE AND ASSIMILATION EFFICIENCY EARTHWORM Pheretima javanica Gates

    Directory of Open Access Journals (Sweden)

    Erwin Nofyan

    2016-11-01

    Full Text Available Research about “Giving a mixture of Insecticide Carbofuran in cow feces to the Rate of Consumption and the Efficiency of Absorption on Land Worm Pheretima javanica Gates was held on June to August 2016 at Animal Physiology Laboratorium, Biology Department, Faculty of Mathematics and Science, Sriwijaya University, Indralaya, Ogan Ilir, South Sumatera. The purpose of this research is to learn the effect of Insecticide Carbofuran to the rate of consumption and the efficiency of absorption on land worm Pheretima javanica Gates. Contribution of this research gives the information to farmer about the effect of insecticide carbofuran to non-target animal, especially to land worm Pheretima javanica Gates. This research used Completely Randomized Design with 6 treatments and 5 times repetition. Treatment that was given to sample are the insecticide carbofuran with concentration of  0 % (control; 0.1% ;  0.2 % ; 0.3 % ;  0.4 % ; 0.5 %. Data analysis was using Varians Analysis. If there was real difference then data analysis continued with The Duncan Test on level of confidence of  95%. The results of this research show us that several concentration of insecticide carbofuran have the real effect to the average of consumption rate and the efficiency of absorption. The lowest average of consumption rate on land worm  Pheretima javanica is on concentration of 0,5 % (0.23 ± 0.02  mg/g day and the highest average of consumption rate on land worm  Pheretima javanica is on concentration of 0% (control (2.53 ± 0.05 mg/g day. The lowest average of absorption efficiency on land worm  Pheretima javanica is on concentration of 0 % (control (40.78  ± 2.56 % and the highest average of absorption efficiency on land worm  Pheretima javanica is on concentration of 0,5 % (70.76  ± 3.67 %.   Keywords: carbofuran, the rate of consumption, the efficiency of absorption, Pheretima javanica Gates.

  16. The Sensitivity of Heavy Precipitation to Horizontal Resolution, Domain Size, and Rain Rate Assimilation: Case Studies with a Convection-Permitting Model

    Directory of Open Access Journals (Sweden)

    Xingbao Wang

    2016-01-01

    Full Text Available The Australian Community Climate and Earth-System Simulator (ACCESS is used to test the sensitivity of heavy precipitation to various model configurations: horizontal resolution, domain size, rain rate assimilation, perturbed physics, and initial condition uncertainties, through a series of convection-permitting simulations of three heavy precipitation (greater than 200 mm day−1 cases in different synoptic backgrounds. The larger disparity of intensity histograms and rainfall fluctuation caused by different model configurations from their mean and/or control run indicates that heavier precipitation forecasts have larger uncertainty. A cross-verification exercise is used to quantify the impacts of different model parameters on heavy precipitation. The dispersion of skill scores with control run used as “truth” shows that the impacts of the model resolution and domain size on the quantitative precipitation forecast are not less than those of perturbed physics and initial field uncertainties in these not intentionally selected heavy precipitation cases. The result indicates that model resolution and domain size should be considered as part of probabilistic precipitation forecasts and ensemble prediction system design besides the model initial field uncertainty.

  17. Uncertainties in the Value of Bill Savings from Behind-the-Meter, Residential Photovoltaic Systems: The Roles of Electricity Market Conditions, Retail Rate Design, and Net Metering

    Science.gov (United States)

    Darghouth, Naim Richard

    Net metering has become a widespread policy mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), allowing customers with PV systems to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption. Although net metering is one of the principal drivers for the residential PV market in the U.S., the academic literature on this policy has been sparse and this dissertation contributes to this emerging body of literature. This dissertation explores the linkages between the availability of net metering, wholesale electricity market conditions, retail rates, and the residential bill savings from behind-the-meter PV systems. First, I examine the value of the bill savings that customers receive under net metering and alternatives to net metering, and the associated role of retail rate design, based on current rates and a sample of approximately two hundred residential customers of California's two largest electric utilities. I find that the bill savings per kWh of PV electricity generated varies greatly, largely attributable to the increasing block structure of the California utilities' residential retail rates. I also find that net metering provides significantly greater bill savings than alternative compensation mechanisms based on avoided costs. However, retail electricity rates may shift as wholesale electricity market conditions change. I then investigate a potential change in market conditions -- increased solar PV penetrations -- on wholesale prices in the short-term based on the merit-order effect. This demonstrates the potential price effects of changes in market conditions, but also points to a number of methodological shortcomings of this method, motivating my usage of a long-term capacity investment and economic dispatch model to examine wholesale price effects of various wholesale market scenarios in the subsequent analysis. By developing

  18. THE APPLICATION OF BŰHLMANN-STRAUB MODEL TO THE ESTIMATION OF NET PREMIUM RATES DEPENDING ON THE AGE OF THE INSURED IN THE MOTOR THIRD LIABILITY INSURANCE

    OpenAIRE

    Szymańska, Anna

    2017-01-01

    One of the basic variables used in the process of tariff calculation of premiums in motor liability insurance is the age of the insured. In this type of insurance offered by insurers operating on the Polish market, this variable is taken into account in the ratemaking by discounts and increases in assigned premium, known as the net premiums rates. The aim of this work is to propose a method of rate estimation of net premiums in the groups of the motor third liability insurance portfolio of in...

  19. Effect of adrenaline and alpha-agonists on net rate of liquid absorption from the pleural space of rabbits.

    Science.gov (United States)

    Zocchi, L; Raffaini, A; Agostoni, E

    1997-05-01

    Indirect evidence supporting a solute-coupled liquid absorption from the pleural space of rabbits has recently been provided; moreover, the beta 2-adrenoceptor agonist terbutaline has been found to increase this absorption. In this study the effect of adrenaline and alpha-adrenoceptor agonists on net rate of liquid absorption (Jnet) from albumin Ringer hydrothoraces of various sizes has been determined in anaesthetized rabbits. In hydrothoraces with adrenaline (5 x 10(-6) M) the relationship between Jnet and volume of liquid injected was displaced upwards by 0.09 ml h-1 relative to that in control hydrothoraces (P liquid absorption, since beta-agonists inhibit lymphatic activity while, at relatively high concentrations, they may increase active transport. Conversely, the strong stimulation of lymphatic alpha-receptors that should occur with adrenaline after beta-blockade may fail to increase lymphatic drainage, because it has been shown that the increase in contraction frequency of lymphatics may be balanced by the decrease in their stroke volume. Arterial blood pressure during the hydrothoraces with adrenaline was unchanged. In hydrothoraces with the alpha 2-agonist clonidine (5 x 10(-6) M; a less potent agent than adrenaline) the slope of the relationship between Jnet and volume injected increased by 26% (P liquid load. In hydrothoraces with the alpha 1-agonist phenylephrine (5 x 10(-6) or 10(-7) M) Jnet was simlar to control values.

  20. Modeled dosage-response relationship on the net photosynthetic rate for the sensitivity to acid rain of 21 plant species.

    Science.gov (United States)

    Deng, Shihuai; Gou, Shuzhen; Sun, Baiye; Lv, Wenlin; Li, Yuanwei; Peng, Hong; Xiao, Hong; Yang, Gang; Wang, Yingjun

    2012-08-01

    This study investigated the sensitivity of plant species to acid rain based on the modeled dosage-response relationship on the net photosynthetic rate (P (N)) of 21 types of plant species, subjected to the exposure of simulated acid rain (SAR) for 5 times during a period of 50 days. Variable responses of P (N) to SAR occurred depending on the type of plant. A majority (13 species) of the dosage-response relationship could be described by an S-shaped curve and be fitted with the Boltzmann model. Model fitting allowed quantitative evaluation of the dosage-response relationship and an accurate estimation of the EC(10), termed as the pH of the acid rain resulting in a P (N) 10 % lower than the reference value. The top 9 species (Camellia sasanqua, Cinnamomum camphora, etc. EC(10) ≤ 3.0) are highly endurable to very acid rain. The rare, relict plant Metasequoia glyptostroboides was the most sensitive species (EC(10) = 5.1) recommended for protection.

  1. Net CO2 exchange rates in three different successional stages of the 'Dark Taiga' of central Siberia

    International Nuclear Information System (INIS)

    Roeser, C.; Schulze, E.D.; Montagnani, L.

    2002-01-01

    The net ecosystem exchange (NEE) of successional stages of the Abies-dominated dark taiga was measured in central Siberia (61 deg N, 90 deg E) during the growing season of the year 2000 using the eddy covariance technique. Measurements started before snow melt and canopy activity in spring on day of year (DOY) 99 and lasted until a permanent snow cover had developed and respiration had ceased in autumn DOY 299. Three stands growing in close vicinity were investigated: 50 yr-old Betula pubescens ('Betula stand', an early successional stage after fire), 250 yr-old mixed boreal forest, representing the transition from Betula-dominated to Abies-dominated canopies, and 200-yr-old Abies sibirica ('Abies stand', representing a late successional stage following the mixed boreal forest). The mixed boreal forest had a multi-layered canopy with dense under story and trees of variable height and age below the main canopy, which was dominated by Abies sibirica, Picea obovata and few old Betula pubescens and Populus tremula trees. The Abies stand had a uniform canopy dominated by Abies sibirica. This stand appears to have established not after fire but after wind break or insect damage in a later successional stage. The stands differed with respect to the number of days with net CO 2 uptake (Betula stand 89 days, mixed boreal forest 109 days, and Abies stand 135 days), maximum measured LAI (Betula 2.6 m 2 /m 2 , mixed boreal forest 3.5 m 2 /m 2 and Abies stand 4.1 m 2 /m 2 ) and basal area (Betula stand 30.2 m 2 /ha, mixed boreal forest 35.7 m 2 /ha, and Abies stand 46.5 m 2 /ha). In the mixed boreal forest, many days with net daytime CO 2 release were observed in summer. Both other sites were almost permanent sinks in summer. Mean daytime CO 2 exchange rates in July were 8.45 mol/m 2 /s in the Betula stand, 4.65 mol/m 2 /s in the mixed boreal forest and 6.31 mol/m 2 /s in the Abies stand. Measured uptake for the growing season was 247.2 g C/m 2 in the Betula stand, 99.7 g C/m 2

  2. The CarbonTracker Data Assimilation Shell (CTDAS) v1.0: implementation and global carbon balance 2001-2015

    Science.gov (United States)

    van der Laan-Luijkx, Ingrid T.; van der Velde, Ivar R.; van der Veen, Emma; Tsuruta, Aki; Stanislawska, Karolina; Babenhauserheide, Arne; Zhang, Hui Fang; Liu, Yu; He, Wei; Chen, Huilin; Masarie, Kenneth A.; Krol, Maarten C.; Peters, Wouter

    2017-07-01

    Data assimilation systems are used increasingly to constrain the budgets of reactive and long-lived gases measured in the atmosphere. Each trace gas has its own lifetime, dominant sources and sinks, and observational network (from flask sampling and in situ measurements to space-based remote sensing) and therefore comes with its own optimal configuration of the data assimilation. The CarbonTracker Europe data assimilation system for CO2 estimates global carbon sources and sinks, and updates are released annually and used in carbon cycle studies. CarbonTracker Europe simulations are performed using the new modular implementation of the data assimilation system: the CarbonTracker Data Assimilation Shell (CTDAS). Here, we present and document this redesign of the data assimilation code that forms the heart of CarbonTracker, specifically meant to enable easy extension and modification of the data assimilation system. This paper also presents the setup of the latest version of CarbonTracker Europe (CTE2016), including the use of the gridded state vector, and shows the resulting carbon flux estimates. We present the distribution of the carbon sinks over the hemispheres and between the land biosphere and the oceans. We show that with equal fossil fuel emissions, 2015 has a higher atmospheric CO2 growth rate compared to 2014, due to reduced net land carbon uptake in later year. The European carbon sink is especially present in the forests, and the average net uptake over 2001-2015 was 0. 17 ± 0. 11 PgC yr-1 with reductions to zero during drought years. Finally, we also demonstrate the versatility of CTDAS by presenting an overview of the wide range of applications for which it has been used so far.

  3. Long-term influence of tillage and fertilization on net carbon dioxide exchange rate on two soils with different textures.

    Science.gov (United States)

    Feiziene, Dalia; Feiza, Virginijus; Slepetiene, Alvyra; Liaudanskiene, Inga; Kadziene, Grazina; Deveikyte, Irena; Vaideliene, Asta

    2011-01-01

    The importance of agricultural practices to greenhouse gas mitigation is examined worldwide. However, there is no consensus on soil organic carbon (SOC) content and CO emissions as affected by soil management practices and their relationships with soil texture. No-till (NT) agriculture often results in soil C gain, though, not always. Soil net CO exchange rate (NCER) and environmental factors (SOC, soil temperature [T], and water content [W]), as affected by soil type (loam and sandy loam), tillage (conventional, reduced, and NT), and fertilization, were quantified in long-term field experiments in Lithuania. Soil tillage and fertilization affected total CO flux (heterotrophic and autotrophic) through effect on soil SOC sequestration, water, and temperature regime. After 11 yr of different tillage and fertilization management, SOC content was 23% more in loam than in sandy loam. Long-term NT contributed to 7 to 27% more SOC sequestration on loam and to 29 to 33% more on sandy loam compared with reduced tillage (RT) or conventional tillage (CT). Soil water content in loam was 7% more than in sandy loam. Soil gravimetric water content, averaged across measurement dates and fertilization treatments, was significantly less in NT than CT and RT in both soils. Soil organic carbon content and water storage capacity of the loam and sandy loam soils exerted different influences on NCER. The NCER from the sandy loam soil was 13% greater than that from the loam. In addition, NCER was 4 to 9% less with NT than with CT and RT systems on both loam and sandy loam soils. Application of mineral NPK fertilizers promoted significantly greater NCER from loam but suppressed NCER by 15% from sandy loam. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. [Effects of plastic film mulching and nitrogen application rate on net global warming potential in semiarid rain-fed maize cropland].

    Science.gov (United States)

    Liu, Jian Can; Wang, Ze Lin; Yue, Shan Chao; Li, Shi Qing

    2018-04-01

    A one-year field experiment was conducted to evaluate the effects of plastic film mulching (FM) and nitrogen application rates applied to rain-fed maize fields on net global warming potential (Net GWP) and greenhouse gas intensity (GHGI) at the Changwu Agricultural and Ecological Experimental Station. Both GWP and GHGI were affected by the plastic film mulching and nitrogen application rate. Under the FM treatment, maize yield ranged from 1643 to 16699 kg·hm -2 , the net GWP (CO 2 -eq) ranged from 595 to 4376 kg·hm -2 ·a -1 , and the GHGI (CO 2 -eq) ranged from 213 to 358 kg·t -1 . The grain yield of maize, net GWP and GHGI for the UM (no mulching) treatment were 956 to 8821 kg·hm -2 , 342 to 4004 kg·hm -2 ·a -1 and 204 to 520 kg·t -1 , respectively. The results suggested that plastic film mulching could simultaneously improve grain yield and decrease GHGI in rain-fed cropland along with nitrogen fertilizer of 250 kg·hm -2 .

  5. Diverging temperature responses of CO2 assimilation and plant development explain the overall effect of temperature on biomass accumulation in wheat leaves and grains.

    Science.gov (United States)

    Collins, Nicholas C; Parent, Boris

    2017-01-09

    There is a growing consensus in the literature that rising temperatures influence the rate of biomass accumulation by shortening the development of plant organs and the whole plant and by altering rates of respiration and photosynthesis. A model describing the net effects of these processes on biomass would be useful, but would need to reconcile reported differences in the effects of night and day temperature on plant productivity. In this study, the working hypothesis was that the temperature responses of CO 2 assimilation and plant development rates were divergent, and that their net effects could explain observed differences in biomass accumulation. In wheat (Triticum aestivum) plants, we followed the temperature responses of photosynthesis, respiration and leaf elongation, and confirmed that their responses diverged. We measured the amount of carbon assimilated per "unit of plant development" in each scenario and compared it to the biomass that accumulated in growing leaves and grains. Our results suggested that, up to a temperature optimum, the rate of any developmental process increased with temperature more rapidly than that of CO 2 assimilation and that this discrepancy, summarised by the CO 2 assimilation rate per unit of plant development, could explain the observed reductions in biomass accumulation in plant organs under high temperatures. The model described the effects of night and day temperature equally well, and offers a simple framework for describing the effects of temperature on plant growth. Published by Oxford University Press on behalf of the Annals of Botany Company.

  6. Are HPV vaccination services accessible to high-risk communities? A spatial analysis of HPV-associated cancer and Chlamydia rates and safety-net clinics.

    Science.gov (United States)

    Tsui, Jennifer; Rodriguez, Hector P; Gee, Gilbert C; Escobedo, Loraine A; Kominski, Gerald F; Bastani, Roshan

    2013-12-01

    While HPV vaccines can greatly benefit adolescents and young women from high-risk areas, little is known about whether safety-net immunization services are geographically accessible to communities at greatest risk for HPV-associated diseases. We explore the spatial relationship between areas with high HPV risk and proximity to safety-net clinics from an ecologic perspective. We used cancer registry data and Chlamydia surveillance data to identify neighborhoods within Los Angeles County with high risk for HPV-associated cancers. We examined proximity to safety-net clinics among neighborhoods with the highest risk. Proximity was measured as the shortest distance between each neighborhood center and the nearest clinic and having a clinic within 3 miles of each neighborhood center. The average 5-year non-age-adjusted rates were 1,940 cases per 100,000 for Chlamydia and 60 per 100,000 for HPV-associated cancers. A large majority, 349 of 386 neighborhoods with high HPV-associated cancer rates and 532 of 537 neighborhoods with high Chlamydia rates, had a clinic within 3 miles of the neighborhood center. Clinics were more likely to be located within close proximity to high-risk neighborhoods in the inner city. High-risk neighborhoods outside of this urban core area were less likely to be near accessible clinics. The majority of high-risk neighborhoods were geographically near safety-net clinics with HPV vaccination services. Due to low rates of vaccination, these findings suggest that while services are geographically accessible, additional efforts are needed to improve uptake. Programs aimed to increase awareness about the vaccine and to link underserved groups to vaccination services are warranted.

  7. Petri Nets

    Indian Academy of Sciences (India)

    In a computer system, for example, typical discrete events ... This project brought out a series of influential reports on Petri net theory in the mid and late ... Technology became a leading centre for Petri net research and from then on, Petri nets ...

  8. WATER QUALITY AND ITS EFFECT ON GROWTH AND SURVIVAL RATE OF LOBSTER REARED IN FLOATING NET CAGE IN EKAS BAY, WEST NUSA TENGGARA PROVINCE

    Directory of Open Access Journals (Sweden)

    Muhammad Junaidi

    2015-02-01

    Full Text Available ABSTRACT The development of lobster farming in floating net cage in Ekas Bay caused an environmental degradation such as decrease water quality due to some aquaculture wastes. The purposes of this study were to determine the status of water quality and their effect on growth and survival rate of lobster reared in floating net cages (FNC in the Ekas Bay, West Nusa Tenggara Province. Water sample collection and handling referred to the APHA (1992. Analyses of water quality data were conducted using Principal Component Analysis. Determination of the water quality status of Ekas Bay was performed with STORET system. Multivariate analyses were used to determine the relationship between water quality, growth, and survival rate of lobster reared in FNC. Results showed that Ekas Bay water quality status was categorized in class C (medium contaminated, which exceeded some quality standard parameters such as ammonia (0.3 mg/l, nitrate (0.008 mg/l, and phosphate (0.015 mg/l. During lobster farming activities feeding with trash fish for 270 days, we obtained daily growth rate of  0.74% (lower than normal growth rate of 0.86%, survival rate of 66% (lower than normal survival rate of 86.7%, and feed conversion ratio of 11.15. Ammonia was found as a dominant factor reducing growth  and survival rate of lobster reared in FNC. Keywords: water quality, lobsters, growth, survival, Ekas Bay

  9. Regional Ocean Data Assimilation

    KAUST Repository

    Edwards, Christopher A.; Moore, Andrew M.; Hoteit, Ibrahim; Cornuelle, Bruce D.

    2015-01-01

    This article reviews the past 15 years of developments in regional ocean data assimilation. A variety of scientific, management, and safety-related objectives motivate marine scientists to characterize many ocean environments, including coastal

  10. Land Surface Data Assimilation

    Science.gov (United States)

    Houser, P. R.

    2012-12-01

    Information about land surface water, energy and carbon conditions is of critical importance to real-world applications such as agricultural production, water resource management, flood prediction, water supply, weather and climate forecasting, and environmental preservation. While ground-based observational networks are improving, the only practical way to observe these land surface states on continental to global scales is via satellites. Remote sensing can make spatially comprehensive measurements of various components of the terrestrial system, but it cannot provide information on the entire system (e.g. evaporation), and the observations represent only an instant in time. Land surface process models may be used to predict temporal and spatial terrestrial dynamics, but these predictions are often poor, due to model initialization, parameter and forcing, and physics errors. Therefore, an attractive prospect is to combine the strengths of land surface models and observations (and minimize the weaknesses) to provide a superior terrestrial state estimate. This is the goal of land surface data assimilation. Data Assimilation combines observations into a dynamical model, using the model's equations to provide time continuity and coupling between the estimated fields. Land surface data assimilation aims to utilize both our land surface process knowledge, as embodied in a land surface model, and information that can be gained from observations. Both model predictions and observations are imperfect and we wish to use both synergistically to obtain a more accurate result. Moreover, both contain different kinds of information, that when used together, provide an accuracy level that cannot be obtained individually. Model biases can be mitigated using a complementary calibration and parameterization process. Limited point measurements are often used to calibrate the model(s) and validate the assimilation results. This presentation will provide a brief background on land

  11. Net Neutrality

    DEFF Research Database (Denmark)

    Savin, Andrej

    2017-01-01

    Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else.......Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else....

  12. Dependence of wheat and rice respiration on tissue nitrogen and the corresponding net carbon fixation efficiency under different rates of nitrogen application

    Science.gov (United States)

    Sun, Wenjuan; Huang, Yao; Chen, Shutao; Zou, Jianwen; Zheng, Xunhua

    2007-02-01

    To quantitatively address the role of tissue N in crop respiration under various agricultural practices, and to consequently evaluate the impact of synthetic fertilizer N application on biomass production and respiration, and hence net carbon fixation efficiency ( E ncf), pot and field experiments were carried out for an annual rotation of a rice-wheat cropping system from 2001 to 2003. The treatments of the pot experiments included fertilizer N application, sowing date and planting density. Different rates of N application were tested in the field experiments. Static opaque chambers were used for sampling the gas. The respiration as CO2 emission was detected by a gas chromatograph. A successive biomass clipping method was employed to determine the crop autotrophic respiration coefficient ( R a). Results from the pot experiments revealed a linear relationship between R a and tissue N content as R a = 4.74N-1.45 ( R 2 = 0.85, P < 0.001). Measurements and calculations from the field experiments indicated that fertilizer N application promoted not only biomass production but also increased the respiration of crops. A further investigation showed that the increase of carbon loss in terms of respiration owing to fertilizer N application exceeded that of net carbon gain in terms of aboveground biomass when fertilizer N was applied over a certain rate. Consequently, the E ncf declined as the N application rate increased.

  13. Displacement data assimilation

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, W. Steven [Pacific Northwest Laboratory, Richland, WA 99354 (United States); Venkataramani, Shankar [Department of Mathematics and Program in Applied Mathematics, University of Arizona, Tucson, AZ 85721 (United States); Mariano, Arthur J. [Rosenstiel School of Marine & Atmospheric Science, University of Miami, Miami, FL 33149 (United States); Restrepo, Juan M., E-mail: restrepo@math.oregonstate.edu [Department of Mathematics, Oregon State University, Corvallis, OR 97331 (United States)

    2017-02-01

    We show that modifying a Bayesian data assimilation scheme by incorporating kinematically-consistent displacement corrections produces a scheme that is demonstrably better at estimating partially observed state vectors in a setting where feature information is important. While the displacement transformation is generic, here we implement it within an ensemble Kalman Filter framework and demonstrate its effectiveness in tracking stochastically perturbed vortices.

  14. The HLA-net GENE[RATE] pipeline for effective HLA data analysis and its application to 145 population samples from Europe and neighbouring areas.

    Science.gov (United States)

    Nunes, J M; Buhler, S; Roessli, D; Sanchez-Mazas, A

    2014-05-01

    In this review, we present for the first time an integrated version of the Gene[rate] computer tools which have been developed during the last 5 years to analyse human leukocyte antigen (HLA) data in human populations, as well as the results of their application to a large dataset of 145 HLA-typed population samples from Europe and its two neighbouring areas, North Africa and West Asia, now forming part of the Gene[va] database. All these computer tools and genetic data are, from now, publicly available through a newly designed bioinformatics platform, HLA-net, here presented as a main achievement of the HLA-NET scientific programme. The Gene[rate] pipeline offers user-friendly computer tools to estimate allele and haplotype frequencies, to test Hardy-Weinberg equilibrium (HWE), selective neutrality and linkage disequilibrium, to recode HLA data, to convert file formats, to display population frequencies of chosen alleles and haplotypes in selected geographic regions, and to perform genetic comparisons among chosen sets of population samples, including new data provided by the user. Both numerical and graphical outputs are generated, the latter being highly explicit and of publication quality. All these analyses can be performed on the pipeline after scrupulous validation of the population sample's characterisation and HLA typing reporting according to HLA-NET recommendations. The Gene[va] database offers direct access to the HLA-A, -B, -C, -DQA1, -DQB1, -DRB1 and -DPB1 frequencies and summary statistics of 145 population samples having successfully passed these HLA-NET 'filters', and representing three European subregions (South-East, North-East and Central-West Europe) and two neighbouring areas (North Africa, as far as Sudan, and West Asia, as far as South India). The analysis of these data, summarized in this review, shows a substantial genetic variation at the regional level in this continental area. These results have main implications for population genetics

  15. Petri Nets

    Indian Academy of Sciences (India)

    GENERAL I ARTICLE ... In Part 1 of this two-part article, we have seen im- ..... mable logic controller and VLSI arrays, office automation systems, workflow management systems, ... complex discrete event and real-time systems; and Petri nets.

  16. Quantitative estimation of net rates of production of bacterial and protozoal nitrogen and their interconversion in the rumen

    International Nuclear Information System (INIS)

    El-Fouly, H.A.

    1983-01-01

    A technique is described using 35 S-labelled bacteria or protozoa by which the rates of production of microbial and protozoal protein N may be calculated. The results indicate an average microbial protein yield of about 13.7gN.d -1 in sheep maintained on a diet consisting largely of cottonseed cake and wheat and rice bran. Evidence is presented that protozoa made little contribution to the microbial protein-N leaving the rumen. Also, the average rate of N flow from the protozoal to the bacterial pool was about 3.5g.d -1 , whereas about 1.4g.d -1 of bacterial N was consumed by protozoa. (author)

  17. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, K.D.; Fronning, B.E.; Kravchenko, A.; Min, D.H.; Robertson, G.P. [Michigan State University, East Lansing, MI 48824 (United States)

    2010-07-15

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m{sup -2} y{sup -1}, respectively, compared to 52 g m{sup -2} y{sup -1} for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation. (author)

  18. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    International Nuclear Information System (INIS)

    Thelen, K.D.; Fronning, B.E.; Kravchenko, A.; Min, D.H.; Robertson, G.P.

    2010-01-01

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m -2 y -1 , respectively, compared to 52 g m -2 y -1 for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation.

  19. Aeration to degas CO{sub 2}, increase pH, and increase iron oxidation rates for efficient treatment of net alkaline mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, C.S.; Dennis, A.; Kahler, A. [Bucknell University, Lewisburg, PA (United States). Dept. of Geology

    2009-07-15

    Passive treatment systems for mine drainage use no energy other than gravity, but they require greater area than active treatment systems. Researchers are considering 'hybrid' systems that have passive and active components for increased efficiency, especially where space limitations render passive-only technology ineffective. Flow-through reactor field experiments were conducted at two large net-alkaline anthracite mine discharges in central Pennsylvania. Assuming an Fe removal rate of 20 g m{sup -2} day{sup -1} and Fe loading from field data, 3.6 x 10{sup 3} and 3.0 x 10{sup 4} m{sup 2} oxidation ponds would be required for the passive treatment of Site 21 and Packer 5 discharges, respectively. However, only a small area is available at each site. This paper demonstrates aeration to drive off CO{sub 2}, increase pH, and increase Fe(II) oxidation rates, enabling treatment within a small area compared to passive treatment methods, and introduces a geochemical model to accurately predict these rates as well as semi-passive treatment system sizing parameters. Iron(II) oxidation modeling of actively aerated systems predicted that a 1-m deep pond with 10 times less area than estimated for passive treatment would lower Fe(II) concentrations to less than 1 mg L-1 at summer and winter temperatures for both sites. The use of active aeration for treatment Of CO{sub 2}-rich, net-alkaline discharges (including partially treated effluent from anoxic limestone drains) can result in considerably reduced treatment area for oxidation and may lower treatment costs, but settling of Fe hydroxides was not considered in this study. The reduced capital cost for earthmoving will need to be compared to energy and maintenance costs for aeration.

  20. Mosquito abundance, bed net coverage and other factors associated with variations in sporozoite infectivity rates in four villages of rural Tanzania

    DEFF Research Database (Denmark)

    Kweka, Eliningaya J; Nkya, Watoky M M; Mahande, Aneth M

    2008-01-01

    . Sporozoite infectivity rates, mosquito host blood meal source, bed net coverage and mosquito abundance were assessed in this study. METHODOLOGY: A longitudinal survey was conducted in four villages in two regions of Tanzania. Malaria vectors were sampled using the CDC light trap and pyrethrum spray catch...... methods. In each village, ten paired houses were selected for mosquitoes sampling. Sampling was done in fortnight case and study was undertaken for six months in both Kilimanjaro (Northern Tanzania) and Dodoma (Central Tanzania) regions. RESULTS: A total of 6,883 mosquitoes were collected including: 5......,628 (81.8%) Anopheles arabiensis, 1,100 (15.9%) Culex quinquefasciatus, 89 (1.4%) Anopheles funestus, and 66 (0.9%) Anopheles gambiae s.s. Of the total mosquitoes collected 3,861 were captured by CDC light trap and 3,022 by the pyrethrum spray catch method. The overall light trap: spray catch ratio was 1...

  1. RESTful NET

    CERN Document Server

    Flanders, Jon

    2008-01-01

    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  2. Improved netting

    International Nuclear Information System (INIS)

    Bramley, A.; Clabburn, R.J.T.

    1976-01-01

    A method is described for producing netting composed of longitudinal and transverse threads of irradiation cross linked thermoplastic material, the threads being joined together at their crossings by moulded masses of cross linked thermoplastic material. The thread may be formed of polyethylene filaments, subjected to a radiation dose of 15 to 25 MR. The moulding can be conducted at 245 0 to 260 0 C or higher. The product is claimed to be an improved quality of netting, with bonds of increased strength between crossing threads. (U.K.)

  3. Aeration to degas CO2, increase pH, and increase iron oxidation rates for efficient treatment of net alkaline mine drainage

    International Nuclear Information System (INIS)

    Kirby, C.S.; Dennis, A.; Kahler, A.

    2009-01-01

    Passive treatment systems for mine drainage use no energy other than gravity, but they require greater area than active treatment systems. Researchers are considering 'hybrid' systems that have passive and active components for increased efficiency, especially where space limitations render passive-only technology ineffective. Flow-through reactor field experiments were conducted at two large net-alkaline anthracite mine discharges in central Pennsylvania. Assuming an Fe removal rate of 20 g m -2 day -1 and Fe loading from field data, 3.6 x 10 3 and 3.0 x 10 4 m 2 oxidation ponds would be required for the passive treatment of Site 21 and Packer 5 discharges, respectively. However, only a small area is available at each site. This paper demonstrates aeration to drive off CO 2 , increase pH, and increase Fe(II) oxidation rates, enabling treatment within a small area compared to passive treatment methods, and introduces a geochemical model to accurately predict these rates as well as semi-passive treatment system sizing parameters. Both net-alkaline discharges were suboxic with a pH of ∼5.7, Fe(II) concentration of ∼16 mg L -1 , and low Mn and Al concentrations. Flow rates were ∼4000 L min -1 at Site 21 and 15,000 L min -1 at Packer 5. Three-h aeration experiments with flow rates scaled to a 14-L reactor resulted in pH increases from 5.7 to greater than 7, temperature increases from 12 to 22 deg. C, dissolved O 2 increases to saturation with respect to the atmosphere, and Fe(II) concentration decreases from 16 to -1 . A 17,000-L pilot-scale reactor at Site 21 produced similar results although aeration was not as complete as in the smaller reactor. Two non-aerated experiments at Site 21 with 13 and 25-h run times resulted in pH changes of ≤0.2 and Fe(II) concentration decreases of less than 3 mg L -1 . An Fe(II) oxidation model written in a differential equation solver matched the field experiments very well using field-measured pH, temperature, dissolved O 2

  4. NetSig

    DEFF Research Database (Denmark)

    Horn, Heiko; Lawrence, Michael S; Chouinard, Candace R

    2018-01-01

    Methods that integrate molecular network information and tumor genome data could complement gene-based statistical tests to identify likely new cancer genes; but such approaches are challenging to validate at scale, and their predictive value remains unclear. We developed a robust statistic (Net......Sig) that integrates protein interaction networks with data from 4,742 tumor exomes. NetSig can accurately classify known driver genes in 60% of tested tumor types and predicts 62 new driver candidates. Using a quantitative experimental framework to determine in vivo tumorigenic potential in mice, we found that Net......Sig candidates induce tumors at rates that are comparable to those of known oncogenes and are ten-fold higher than those of random genes. By reanalyzing nine tumor-inducing NetSig candidates in 242 patients with oncogene-negative lung adenocarcinomas, we find that two (AKT2 and TFDP2) are significantly amplified...

  5. Petri Nets

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Petri Nets - Applications. Y Narahari. General Article Volume 4 Issue 9 September 1999 pp 44-52 ... Author Affiliations. Y Narahari1. Department of Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India.

  6. Net Gain

    International Development Research Centre (IDRC) Digital Library (Canada)

    Describing the effect of tax incentives for import, production, and sale of nets and insecticides; and ..... So far, China is the only country where a system for the routine treatment of ...... 1993), and the trials in Ecuador and Peru (Kroeger et al.

  7. Effects of nitrogen application rates on net annual global warming potential and greenhouse gas intensity in double-rice cropping systems of the Southern China.

    Science.gov (United States)

    Chen, Zhongdu; Chen, Fu; Zhang, Hailin; Liu, Shengli

    2016-12-01

    The net global warming potential (NGWP) and net greenhouse gas intensity (NGHGI) of double-rice cropping systems are not well documented. We measured the NGWP and NGHGI including soil organic carbon (SOC) change and indirect emissions (IE) from double-crop rice fields with fertilizing systems in Southern China. These experiments with three different nitrogen (N) application rates since 2012 are as follows: 165 kgN ha -1 for early rice and 225 kgN ha -1 for late rice (N1), which was the local N application rates as the control; 135 kgN ha -1 for early rice and 180 kgN ha -1 for late rice (N2, 20 % reduction); and 105 kgN ha -1 for early rice and 135 kgN ha -1 for late rice (N3, 40 % reduction). Results showed that yields increased with the increase of N application rate, but without significant difference between N1 and N2 plots. Annual SOC sequestration rate under N1 was estimated to be 1.15 MgC ha -1  year -1 , which was higher than those under other fertilizing systems. Higher N application tended to increase CH 4 emissions during the flooded rice season and significantly increased N 2 O emissions from drained soils during the nonrice season, ranking as N1 > N2 > N3 with significant difference (P < 0.05). Two-year average IE has a huge contribution to GHG emissions mainly coming from the higher N inputs in the double-rice cropping system. Reducing N fertilizer usage can effectively decrease the NGWP and NGHGI in the double-rice cropping system, with the lowest NGHGI obtained in the N2 plot (0.99 kg CO 2 -eq kg -1 yield year -1 ). The results suggested that agricultural economic viability and GHG mitigation can be simultaneously achieved by properly reducing N fertilizer application in double-rice cropping systems.

  8. Spatial Assimilation in Denmark?

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    2010-01-01

    market and discrimination, which limits the housing possibilities for ethnic minorities. Another explanation could be that immigrants for different reasons choose to settle in so-called ethnic enclaves where they can find an ethnic social network, which can support them in their new country....... In traditional research literature about immigration it has been shown that for many immigrants living in enclaves has been a temporary situation. The 'spatial assimilation theory' says that this situation ends when the family has become more integrated in the new society and then moves to other parts...

  9. Regional Ocean Data Assimilation

    KAUST Repository

    Edwards, Christopher A.

    2015-01-03

    This article reviews the past 15 years of developments in regional ocean data assimilation. A variety of scientific, management, and safety-related objectives motivate marine scientists to characterize many ocean environments, including coastal regions. As in weather prediction, the accurate representation of physical, chemical, and/or biological properties in the ocean is challenging. Models and observations alone provide imperfect representations of the ocean state, but together they can offer improved estimates. Variational and sequential methods are among the most widely used in regional ocean systems, and there have been exciting recent advances in ensemble and four-dimensional variational approaches. These techniques are increasingly being tested and adapted for biogeochemical applications.

  10. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps......, to location-based social networks and games, such as Foursquare and facebook. Warns of the threats these technologies, such as data surveillance, present to our sense of privacy, while also outlining the opportunities for pro-social developments. Provides a theory of the web in the context of the history...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  11. A study on assimilating potential vorticity data

    Science.gov (United States)

    Li, Yong; Ménard, Richard; Riishøjgaard, Lars Peter; Cohn, Stephen E.; Rood, Richard B.

    1998-08-01

    The correlation that exists between the potential vorticity (PV) field and the distribution of chemical tracers such as ozone suggests the possibility of using tracer observations as proxy PV data in atmospheric data assimilation systems. Especially in the stratosphere, there are plentiful tracer observations but a general lack of reliable wind observations, and the correlation is most pronounced. The issue investigated in this study is how model dynamics would respond to the assimilation of PV data. First, numerical experiments of identical-twin type were conducted with a simple univariate nuding algorithm and a global shallow water model based on PV and divergence (PV-D model). All model fields are successfully reconstructed through the insertion of complete PV data alone if an appropriate value for the nudging coefficient is used. A simple linear analysis suggests that slow modes are recovered rapidly, at a rate nearly independent of spatial scale. In a more realistic experiment, appropriately scaled total ozone data from the NIMBUS-7 TOMS instrument were assimilated as proxy PV data into the PV-D model over a 10-day period. The resulting model PV field matches the observed total ozone field relatively well on large spatial scales, and the PV, geopotential and divergence fields are dynamically consistent. These results indicate the potential usefulness that tracer observations, as proxy PV data, may offer in a data assimilation system.

  12. Diurnal changes of net photosynthetic rate (NPR) in leaves of Lonicera japonica Thunb. and the responding mathematical model of NPR to photosynthetic valid radiation

    International Nuclear Information System (INIS)

    Wu Dafu; Zhang Shengli; Li Dongfang

    2009-01-01

    [Objective] The study provided theoretical basis for production practice . [Method] With Lonicera japonica Thunb .as material, diurnal changes of net photosynthetic rate (NPR) in leaves of the plant and the responding mathematical model of NPR to photosynthetic valid radiation were studied using portable photosynthetic determinator system. [Result] Like most of C3 plants, the diurnal changes curve of NPR of Lonicera japonica Thunb .showed double peaks, but there were time difference in reaching the peak value between the study and previous ones . The responding mathematical model of NPR to photosynthetic valid radiation could be described by three mathematic functions, such as logarithm, linearity and binomial, but binomial function was more precise than the others. Light saturation point of Lonicera japonica Thunb. was figured out by binomial equation deduced in the study , and light saturation point was 1 086 .3 μmol/ (m2•s) . [Conclusion] The diurnal changes curve of NPR of Lonicera japonica Thunb .showed double peaks, and the responding mathematical model of NPR to photosynthetic valid radiation could be described by binomial functions

  13. Nonlinear data assimilation

    CERN Document Server

    Van Leeuwen, Peter Jan; Reich, Sebastian

    2015-01-01

    This book contains two review articles on nonlinear data assimilation that deal with closely related topics but were written and can be read independently. Both contributions focus on so-called particle filters. The first contribution by Jan van Leeuwen focuses on the potential of proposal densities. It discusses the issues with present-day particle filters and explorers new ideas for proposal densities to solve them, converging to particle filters that work well in systems of any dimension, closing the contribution with a high-dimensional example. The second contribution by Cheng and Reich discusses a unified framework for ensemble-transform particle filters. This allows one to bridge successful ensemble Kalman filters with fully nonlinear particle filters, and allows a proper introduction of localization in particle filters, which has been lacking up to now.

  14. Parametric Net Influx Rate Images of 68Ga-DOTATOC and 68Ga-DOTATATE: Quantitative Accuracy and Improved Image Contrast.

    Science.gov (United States)

    Ilan, Ezgi; Sandström, Mattias; Velikyan, Irina; Sundin, Anders; Eriksson, Barbro; Lubberink, Mark

    2017-05-01

    68 Ga-DOTATOC and 68 Ga-DOTATATE are radiolabeled somatostatin analogs used for the diagnosis of somatostatin receptor-expressing neuroendocrine tumors (NETs), and SUV measurements are suggested for treatment monitoring. However, changes in net influx rate ( K i ) may better reflect treatment effects than those of the SUV, and accordingly there is a need to compute parametric images showing K i at the voxel level. The aim of this study was to evaluate parametric methods for computation of parametric K i images by comparison to volume of interest (VOI)-based methods and to assess image contrast in terms of tumor-to-liver ratio. Methods: Ten patients with metastatic NETs underwent a 45-min dynamic PET examination followed by whole-body PET/CT at 1 h after injection of 68 Ga-DOTATOC and 68 Ga-DOTATATE on consecutive days. Parametric K i images were computed using a basis function method (BFM) implementation of the 2-tissue-irreversible-compartment model and the Patlak method using a descending aorta image-derived input function, and mean tumor K i values were determined for 50% isocontour VOIs and compared with K i values based on nonlinear regression (NLR) of the whole-VOI time-activity curve. A subsample of healthy liver was delineated in the whole-body and K i images, and tumor-to-liver ratios were calculated to evaluate image contrast. Correlation ( R 2 ) and agreement between VOI-based and parametric K i values were assessed using regression and Bland-Altman analysis. Results: The R 2 between NLR-based and parametric image-based (BFM) tumor K i values was 0.98 (slope, 0.81) and 0.97 (slope, 0.88) for 68 Ga-DOTATOC and 68 Ga-DOTATATE, respectively. For Patlak analysis, the R 2 between NLR-based and parametric-based (Patlak) tumor K i was 0.95 (slope, 0.71) and 0.92 (slope, 0.74) for 68 Ga-DOTATOC and 68 Ga-DOTATATE, respectively. There was no bias between NLR and parametric-based K i values. Tumor-to-liver contrast was 1.6 and 2.0 times higher in the parametric

  15. Assimilation of water and dietary ions by the gastrointestinal tract during digestion in seawater-acclimated rainbow trout.

    Science.gov (United States)

    Bucking, Carol; Fitzpatrick, John L; Nadella, Sunita R; McGaw, Iain J; Wood, Chris M

    2011-07-01

    Recent studies focusing on the consequences of feeding for ion and water balance in freshwater fish have revealed the need for similar comparative studies in seawater fish. A detailed time course sampling of gastrointestinal (GI) tract contents following the ingestion of a single meal of a commercial diet revealed the assimilation of both water and dietary ions (Na(+), Cl(-), K(+), Ca(2+), Mg(2+)) along the GI tract of seawater-acclimated rainbow trout (Oncorhynchus mykiss) which had been fasted for 1 week. Consumption of the meal did not change the drinking rate. There was a large secretion of fluid into the anterior intestine and caecae (presumably bile and/or pancreatic secretions). As a result, net assimilation (63%) of the ingested water along the GI tract was lower than generally reported for fasted trout. Mg(2+) was neither secreted into nor absorbed from the GI tract on a net basis. Only K(+) (93% assimilated) and Ca(2+) (43% assimilated) were absorbed in amounts in excess of those provided by ingested seawater, suggesting that dietary sources of K(+) and Ca(2+) may be important to seawater teleosts. The oesophagus-stomach served as a major site of absorption for Na(+), Cl(-), K(+), Ca(2+), and Mg(2+), and the anterior intestine and caecae as a major site of net secretion for all of these ions, except Cl(-). Despite large absorptive fluxes of these ions, the ionic composition of the plasma was maintained during the digestion of the meal. The results of the present study were compared with previous work on freshwater-acclimated rainbow trout, highlighting some important differences, but also several similarities on the assimilation of water and ions along the gastrointestinal tract during digestion. This study highlights the complicated array of ion and water transport that occurs in the intestine during digestion while revealing the importance of dietary K(+) and Ca(2+) to seawater-acclimated rainbow trout. Additionally, this study reveals that digestion

  16. Disconfirmed hedonic expectations produce perceptual contrast, not assimilation.

    Science.gov (United States)

    Zellner, Debra A; Strickhouser, Dinah; Tornow, Carina E

    2004-01-01

    In studies of hedonic ratings, contrast is the usual result when expectations about test stimuli are produced through the presentation of context stimuli, whereas assimilation is the usual result when expectations about test stimuli are produced through labeling, advertising, or the relaying of information to the subject about the test stimuli. Both procedures produce expectations that are subsequently violated, but the outcomes are different. The present studies demonstrate that both assimilation and contrast can occur even when expectations are produced by verbal labels and the degree of violation of the expectation is held constant. One factor determining whether assimilation or contrast occurs appears to be the certainty of the expectation. Expectations that convey certainty are produced by methods that lead to social influence on subjects' ratings, producing assimilation. When social influence is not a factor and subjects give judgments influenced only by the perceived hedonic value of the stimulus, contrast is the result.

  17. Modelling fungal sink competitiveness with grains for assimilates in wheat infected by a biotrophic pathogen

    Science.gov (United States)

    Bancal, Marie-Odile; Hansart, Amandine; Sache, Ivan; Bancal, Pierre

    2012-01-01

    Background and Aims Experiments have shown that biotrophic fungi divert assimilates for their growth. However, no attempt has been made either to account for this additional sink or to predict to what extent it competes with both grain filling and plant reserve metabolism for carbon. Fungal sink competitiveness with grains was quantified by a mixed experimental–modelling approach based on winter wheat infected by Puccinia triticina. Methods One week after anthesis, plants grown under controlled conditions were inoculated with varying loads. Sporulation was recorded while plants underwent varying degrees of shading, ensuring a range of both fungal sink and host source levels. Inoculation load significantly increased both sporulating area and rate. Shading significantly affected net assimilation, reserve mobilization and sporulating area, but not grain filling or sporulation rates. An existing carbon partitioning (source–sink) model for wheat during the grain filling period was then enhanced, in which two parameters characterize every sink: carriage capacity and substrate affinity. Fungal sink competitiveness with host sources and sinks was modelled by representing spore production as another sink in diseased wheat during grain filling. Key Results Data from the experiment were fitted to the model to provide the fungal sink parameters. Fungal carriage capacity was 0·56 ± 0·01 µg dry matter °Cd−1 per lesion, much less than grain filling capacity, even in highly infected plants; however, fungal sporulation had a competitive priority for assimilates over grain filling. Simulation with virtual crops accounted for the importance of the relative contribution of photosynthesis loss, anticipated reserve depletion and spore production when light level and disease severity vary. The grain filling rate was less reduced than photosynthesis; however, over the long term, yield loss could double because the earlier reserve depletion observed here would shorten the

  18. Uncertainties in the Value of Bill Savings from Behind-the-Meter, Residential Photovoltaic Systems: The Roles of Electricity Market Conditions, Retail Rate Design, and Net Metering

    OpenAIRE

    Darghouth, Naim Richard

    2013-01-01

    Net metering has become a widespread policy mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), allowing customers with PV systems to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption. Although net metering is one of the principal drivers for the residential PV market in the U.S., the academic literature on this policy has been sparse and this dissertation co...

  19. Study on transference of assimilate in filling summer maize using isotope 14C

    International Nuclear Information System (INIS)

    Fan Zhongxue; Wang Pu; Liang Zhenxing

    2001-01-01

    The dynamic of assimilate transference from the ear leaf to grain during effective grain filling stage was studied by 14 C tracer. The results showed that the rates of assimilate transportation out of the ear leaf and transference to grain changed very fast. The rate was very big in 4 - 6 hour just after 14 C feeding and decreased with time. The grain which accumulated 14 C-assimilate in a higher rate and got much more 14 C-assimilate in fixed time could develop into larger size

  20. Global Data Assimilation System (GDAS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Data Assimilation System (GDAS) is the system used by the Global Forecast System (GFS) model to place observations into a gridded model space for the...

  1. Data assimilation in hydrological modelling

    DEFF Research Database (Denmark)

    Drecourt, Jean-Philippe

    Data assimilation is an invaluable tool in hydrological modelling as it allows to efficiently combine scarce data with a numerical model to obtain improved model predictions. In addition, data assimilation also provides an uncertainty analysis of the predictions made by the hydrological model....... In this thesis, the Kalman filter is used for data assimilation with a focus on groundwater modelling. However the developed techniques are general and can be applied also in other modelling domains. Modelling involves conceptualization of the processes of Nature. Data assimilation provides a way to deal...... with model non-linearities and biased errors. A literature review analyzes the most popular techniques and their application in hydrological modelling. Since bias is an important problem in groundwater modelling, two bias aware Kalman filters have been implemented and compared using an artificial test case...

  2. Data Assimilation in Marine Models

    DEFF Research Database (Denmark)

    Frydendall, Jan

    maximum likelihood framework. These issues are discussed in paper B. The third part of the thesis falls a bit out of the above context is work published in papers C, F. In the first paper, a simple data assimilation scheme was investigated to examine the potential benefits of incorporating a data......This thesis consists of six research papers published or submitted for publication in the period 2006-2009 together with a summary report. The main topics of this thesis are nonlinear data assimilation techniques and estimation in dynamical models. The focus has been on the nonlinear filtering...... techniques for large scale geophysical numerical models and making them feasible to work with in the data assimilation framework. The filtering techniques investigated are all Monte Carlo simulation based. Some very nice features that can be exploited in the Monte Carlo based data assimilation framework from...

  3. Analisis Determinan Net Ekspor Indonesia

    OpenAIRE

    Daulay, Rahmawaty

    2010-01-01

    This study is to analyzing empirically among Indonesia GDP, trade partnership GDP (Malaysia, Singapore, US and Thailand) and real exchange rate toward Indonesia Net Export. To find out which one from those three variables is significant in order to fluctuating (increasing or decreasing) Indonesia Net Export either in the short run or in the long run. Data collection is obtained using secondary data, namely Indonesia GDP, Malaysia GDP, Singapura GDP, US GDP, Thailand GDP and real exchange rate...

  4. Increased light-use efficiency sustains net primary productivity of shaded coffee plants in agroforestry system.

    Science.gov (United States)

    Charbonnier, Fabien; Roupsard, Olivier; le Maire, Guerric; Guillemot, Joannès; Casanoves, Fernando; Lacointe, André; Vaast, Philippe; Allinne, Clémentine; Audebert, Louise; Cambou, Aurélie; Clément-Vidal, Anne; Defrenet, Elsa; Duursma, Remko A; Jarri, Laura; Jourdan, Christophe; Khac, Emmanuelle; Leandro, Patricia; Medlyn, Belinda E; Saint-André, Laurent; Thaler, Philippe; Van Den Meersche, Karel; Barquero Aguilar, Alejandra; Lehner, Peter; Dreyer, Erwin

    2017-08-01

    In agroforestry systems, shade trees strongly affect the physiology of the undergrown crop. However, a major paradigm is that the reduction in absorbed photosynthetically active radiation is, to a certain extent, compensated by an increase in light-use efficiency, thereby reducing the difference in net primary productivity between shaded and non-shaded plants. Due to the large spatial heterogeneity in agroforestry systems and the lack of appropriate tools, the combined effects of such variables have seldom been analysed, even though they may help understand physiological processes underlying yield dynamics. In this study, we monitored net primary productivity, during two years, on scales ranging from individual coffee plants to the entire plot. Absorbed radiation was mapped with a 3D model (MAESPA). Light-use efficiency and net assimilation rate were derived for each coffee plant individually. We found that although irradiance was reduced by 60% below crowns of shade trees, coffee light-use efficiency increased by 50%, leaving net primary productivity fairly stable across all shade levels. Variability of aboveground net primary productivity of coffee plants was caused primarily by the age of the plants and by intraspecific competition among them (drivers usually overlooked in the agroforestry literature) rather than by the presence of shade trees. © 2017 John Wiley & Sons Ltd.

  5. Kinetics of 15NH4+ assimilation in Zea mays

    International Nuclear Information System (INIS)

    Magalhaes, J.R.; Ju, G.C.; Rich, P.J.; Rhodes, D.

    1990-01-01

    Comparative studies of 15 NH 4 + assimilation were undertaken with a GDH1-null mutant of Zea mays and a related (but not strictly isogenic) GDH1-positive wild type from which this mutant was derived. The kinetics of 15 NH 4 + assimilation into free amino acids and total reduced nitrogen were monitored in both roots and shoots of 2-week-old seedlings supplied with 5 millimolar 99% ( 15 NH 4 ) 2 SO 4 via the aerated root medium in hydroponic culture over a 24-h period. The GDH1-null mutant, with a 10- to 15-fold lower total root GDH activity in comparison to the wild type, was found to exhibit a 40 to 50% lower rate of 15 NH 4 + assimilation into total reduced nitrogen. The lower rates of 15 NH 4 + assimilation in the mutant was associated with lower rates of labeling of several free amino acids (including glutamate, glutamine-amino N, aspartate, asparagine-amino N, and alanine) in both roots and shoots of the mutant in comparison to the wild type. Qualitatively, these labeling kinetics appear consistent with a reduced flux of 15 N via glutamate in the GDH1-null mutant. However, the responses of the two genotypes to the potent inhibitor of glutamine synthetase, methionine sulfoximine, and differences in morphology of the two genotypes (particularly a lower shoot:root ratio in the GDH1-null mutant) urge caution in concluding that GDH1 is solely responsible for these differences in ammonia assimilation rate

  6. Effective Assimilation of Global Precipitation

    Science.gov (United States)

    Lien, G.; Kalnay, E.; Miyoshi, T.; Huffman, G. J.

    2012-12-01

    Assimilating precipitation observations by modifying the moisture and sometimes temperature profiles has been shown successful in forcing the model precipitation to be close to the observed precipitation, but only while the assimilation is taking place. After the forecast start, the model tends to "forget" the assimilation changes and lose their extra skill after few forecast hours. This suggests that this approach is not an efficient way to modify the potential vorticity field, since this is the variable that the model would remember. In this study, the ensemble Kalman filter (EnKF) method is used to effectively change the potential vorticity field by allowing ensemble members with better precipitation to receive higher weights. In addition to using an EnKF, two other changes in the precipitation assimilation process are proposed to solve the problems related to the highly non-Gaussian nature of the precipitation variable: a) transform precipitation into a Gaussian distribution based on its climatological distribution, and b) only assimilate precipitation at the location where some ensemble members have positive precipitation. The idea is first tested by the observing system simulation experiments (OSSEs) using SPEEDY, a simplified but realistic general circulation model. When the global precipitation is assimilated in addition to conventional rawinsonde observations, both the analyses and the medium range forecasts are significantly improved as compared to only having rawinsonde observations. The improvement is much reduced when only modifying the moisture field with the same approach, which shows the importance of the error covariance between precipitation and all other model variables. The effect of precipitation assimilation is larger in the Southern Hemisphere than that in the Northern Hemisphere because the Northern Hemisphere analyses are already accurate as a result of denser rawinsonde stations. Assimilation of precipitation using a more comprehensive

  7. The potential for adaptation in a natural Daphnia magna population: broad and narrow-sense heritability of net reproductive rate under Cd stress at two temperatures.

    Science.gov (United States)

    Messiaen, M; Janssen, C R; Thas, O; De Schamphelaere, K A C

    2012-10-01

    The existence of genetic variability is a key element of the adaptive potential of a natural population to stress. In this study we estimated the additive and non-additive components of the genetic variability of net reproductive rate (R(0)) in a natural Daphnia magna population exposed to Cd stress at two different temperatures. To this end, life-table experiments were conducted with 20 parental and 39 offspring clonal lineages following a 2 × 2 design with Cd concentration (control vs. 3.7 μg Cd/L) and temperature (20 vs. 24 °C) as factors. Offspring lineages were obtained through inter-clonal crossing of the different parental lineages. The population mean, additive and non-additive genetic components of variation in each treatment were estimated by fitting an Animal Model to the observed R(0) values using restricted maximum likelihood estimation. From those estimates broad-sense heritabilities (H(2)), narrow-sense heritabilities (h(2)), total (CV(G)) and additive genetic coefficients of variation (CV(A)) of R(0) were calculated. The exposure to Cd imposed a considerable level of stress to the population, as shown by the fact that the population mean of R(0) exposed to Cd was significantly lower than in the control at the corresponding temperature, i.e. by 23 % at 20 °C and by 88 % at 24 °C. The latter difference indicates that increasing temperature increased the stress level imposed by Cd. The H² and CV(G) were significantly greater than 0 in all treatments, suggesting that there is a considerable degree of genetic determination of R(0) in this population and that clonal selection could rapidly lead to increasing population mean fitness under all investigated conditions. More specifically, the H² was 0.392 at 20 °C+Cd and 0.563 at 24 °C+Cd; the CV(G) was 30.0 % at 20 °C+Cd and was significantly higher (147.6 %) in the 24 °C+Cd treatment. Significant values of h(2) (= 0.23) and CV(A) (= 89.7 %) were only found in the 24 °C+Cd treatment, suggesting

  8. Data assimilation approaches in the EURANOS project

    DEFF Research Database (Denmark)

    Kaiser, J.C.; Gering, F.; Astrup, Poul

    2010-01-01

    -nuclides in urban areas the results of demonstration exercises are presented here. With the data assimilation module of the RIMPUFF dispersion code, predictions of the gamma dose rate are corrected with simulated readings of fixed detector stations. Using the DA capabilities of the IAMM package for mapping...... the radioactive contamination in inhabited areas, predictions of a large scale deposition model have been combined with hypothetical measurements on a local scale. In both examples the accuracy of the model predictions has been improved and the uncertainties have been reduced. © EDP Sciences, 2010...

  9. Data Assimilation for Applied Meteorology

    Science.gov (United States)

    Haupt, S. E.

    2012-12-01

    Although atmospheric models provide a best estimate of the future state of the atmosphere, due to sensitivity to initial condition, it is difficult to predict the precise future state. For applied problems, however, users often depend on having accurate knowledge of that future state. To improve prediction of a particular realization of an evolving flow field requires knowledge of the current state of that field and assimilation of local observations into the model. This talk will consider how dynamic assimilation can help address the concerns of users of atmospheric forecasts. First, we will look at the value of assimilation for the renewable energy industry. If the industry decision makers can have confidence in the wind and solar power forecasts, they can build their power allocations around the expected renewable resource, saving money for the ratepayers as well as reducing carbon emissions. We will assess the value to that industry of assimilating local real-time observations into the model forecasts and the value that is provided. The value of the forecasts with assimilation is important on both short (several hour) to medium range (within two days). A second application will be atmospheric transport and dispersion problems. In particular, we will look at assimilation of concentration data into a prediction model. An interesting aspect of this problem is that the dynamics are a one-way coupled system, with the fluid dynamic equations affecting the concentration equation, but not vice versa. So when the observations are of the concentration, one must infer the fluid dynamics. This one-way coupled system presents a challenge: one must first infer the changes in the flow field from observations of the contaminant, then assimilate that to recover both the advecting flow and information on the subgrid processes that provide the mixing. To accomplish such assimilation requires a robust method to match the observed contaminant field to that modeled. One approach is

  10. Seven years of recent European net terrestrial carbon dioxide exchange constrained by atmospheric observations

    NARCIS (Netherlands)

    Peters, W.; Krol, M. C.; van der Werf, G. R.; Houweling, S.; Jones, C. D.; Hughes, J.; Schaefer, K.; Masarie, K. A.; Jacobson, A. R.; Miller, J. B.; Cho, C. H.; Ramonet, M.; Schmidt, M.; Ciattaglia, L.; Apadula, F.; Heltai, D.; Meinhardt, F.; di Sarra, A. G.; Piacentino, S.; Sferlazzo, D.; Aalto, T.; Hatakka, J.; StröM, J.; Haszpra, L.; Meijer, H. A J; van Der Laan, S.; Neubert, R. E M; Jordan, A.; Rodó, X.; Morguí, J. A.; Vermeulen, A. T.; Popa, Maria Elena; Rozanski, K.; Zimnoch, M.; Manning, A. C.; Leuenberger, M.; Uglietti, C.; Dolman, A. J.; Ciais, P.; Heimann, M.; Tans, P.

    2010-01-01

    We present an estimate of net ecosystem exchange (NEE) of CO2 in Europe for the years 2001-2007. It is derived with a data assimilation that uses a large set of atmospheric CO2 mole fraction observations (∼70 000) to guide relatively simple descriptions of terrestrial and oceanic net exchange, while

  11. Seven years of recent European net terrestrial carbon dioxide exchange constrained by atmospheric observations

    NARCIS (Netherlands)

    Peters, W.; Krol, M.C.; Werf, van der G.R.; Houweling, S.; Jones, C.D.; Hughes, J.; Schaefer, K.; Masarie, K.A.

    2010-01-01

    We present an estimate of net ecosystem exchange (NEE) of CO2 in Europe for the years 2001–2007. It is derived with a data assimilation that uses a large set of atmospheric CO2 mole fraction observations (~70 000) to guide relatively simple descriptions of terrestrial and oceanic net exchange, while

  12. Seven years of recent European net terrestrial carbon dioxide exchange constrained by atmospheric observations

    NARCIS (Netherlands)

    Peters, W.; Krol, M; van der Werf, G. R.; Houweling, S.; Jones, C. D.; Hughes, J.; Schaefer, K.; Masarie, K. A.; Jacobson, A. R.; Miller, J. B.; Cho, C. H.; Ramonet, M.; Schmidt, M.; Ciattaglia, L.; Apadula, F.; Helta, D.; Meinhardt, F.; di Sarra, A. G.; Piacentino, S.; Sferlazzo, D.; Aalto, T.; Hatakka, J.; Strom, J.; Haszpra, L.; Meijer, H. A. J.; van der Laan, S.; Neubert, R. E. M.; Jordan, A.; Rodo, X.; Morgui, J. -A.; Vermeulen, A. T.; Popa, E.; Rozanski, K.; Zimnoch, M.; Manning, A. C.; Leuenberger, M.; Uglietti, C.; Dolman, A. J.; Ciais, P.; Heimann, M.; Tans, P. P.; Heltai, D.; Ström, J.

    We present an estimate of net ecosystem exchange (NEE) of CO(2) in Europe for the years 2001-2007. It is derived with a data assimilation that uses a large set of atmospheric CO(2) mole fraction observations (similar to 70 000) to guide relatively simple descriptions of terrestrial and oceanic net

  13. Coupled atmosphere and land-surface assimilation of surface observations with a single column model and ensemble data assimilation

    Science.gov (United States)

    Rostkier-Edelstein, Dorita; Hacker, Joshua P.; Snyder, Chris

    2014-05-01

    types of one-week long numerical experiments are performed: (a) free ensemble runs; (b) ensemble assimilation that directly impacts the atmospheric-state vector only; (c) ensemble assimilation that directly impacts the coupled atmospheric-LS-state vector. The WRF-SCM is run in two modes: with and without inclusion of externally imposed horizontal advection terms in the atmospheric column (derived from the NARR, too). Preliminary examination of analyses and 30-min forecasts of reference height temperature and moisture, soil temperature and moisture at four depths (0.05m, 0.25m, 0.7m and 1.5m), fluxes at the surface, and planetary boundary layer (PBL) height shows that: 1. Horizontal advection is important to the realism of PBL heights and fluxes in the "truth", and affects the depth of influence of the assimilation on the soil state; a deeper effect (that could be non-realistic) is more often observed when advection is not included. 2. Inclusion of soil variables in the state vector can be beneficial to estimates of soil temperature and moisture,of moisture- and net latent heat fluxes at the surface, and of atmospheric variables (for the latter especially when no advection is included), However, no benefit is observed on PBL heights. Further analysis and improvement of the WRF-SCM/DART system (in particular the treatment of advection) is under way.

  14. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1987-01-01

    The author describes a Petri net model, called coloured Petri nets (CP-nets), by means of which it is possible to describe large systems without having to cope with unnecessary details. The author introduces CP-nets and provide a first impression of their modeling power and the suitability...

  15. Learning Visual Basic NET

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Learning Visual Basic .NET is a complete introduction to VB.NET and object-oriented programming. By using hundreds of examples, this book demonstrates how to develop various kinds of applications--including those that work with databases--and web services. Learning Visual Basic .NET will help you build a solid foundation in .NET.

  16. Ecological Assimilation of Land and Climate Observations - the EALCO model

    Science.gov (United States)

    Wang, S.; Zhang, Y.; Trishchenko, A.

    2004-05-01

    Ecosystems are intrinsically dynamic and interact with climate at a highly integrated level. Climate variables are the main driving factors in controlling the ecosystem physical, physiological, and biogeochemical processes including energy balance, water balance, photosynthesis, respiration, and nutrient cycling. On the other hand, ecosystems function as an integrity and feedback on the climate system through their control on surface radiation balance, energy partitioning, and greenhouse gases exchange. To improve our capability in climate change impact assessment, a comprehensive ecosystem model is required to address the many interactions between climate change and ecosystems. In addition, different ecosystems can have very different responses to the climate change and its variation. To provide more scientific support for ecosystem impact assessment at national scale, it is imperative that ecosystem models have the capability of assimilating the large scale geospatial information including satellite observations, GIS datasets, and climate model outputs or reanalysis. The EALCO model (Ecological Assimilation of Land and Climate Observations) is developed for such purposes. EALCO includes the comprehensive interactions among ecosystem processes and climate, and assimilates a variety of remote sensing products and GIS database. It provides both national and local scale model outputs for ecosystem responses to climate change including radiation and energy balances, water conditions and hydrological cycles, carbon sequestration and greenhouse gas exchange, and nutrient (N) cycling. These results form the foundation for the assessment of climate change impact on ecosystems, their services, and adaptation options. In this poster, the main algorithms for the radiation, energy, water, carbon, and nitrogen simulations were diagrammed. Sample input data layers at Canada national scale were illustrated. Model outputs including the Canada wide spatial distributions of net

  17. Nitrogen assimilation in denitrifier Bacillus azotoformans LMG 9581T.

    Science.gov (United States)

    Sun, Yihua; De Vos, Paul; Willems, Anne

    2017-12-01

    Until recently, it has not been generally known that some bacteria can contain the gene inventory for both denitrification and dissimilatory nitrate (NO 3 - )/nitrite (NO 2 - ) reduction to ammonium (NH 4 + ) (DNRA). Detailed studies of these microorganisms could shed light on the differentiating environmental drivers of both processes without interference of organism-specific variation. Genome analysis of Bacillus azotoformans LMG 9581 T shows a remarkable redundancy of dissimilatory nitrogen reduction, with multiple copies of each denitrification gene as well as DNRA genes nrfAH, but a reduced capacity for nitrogen assimilation, with no nas operon nor amtB gene. Here, we explored nitrogen assimilation in detail using growth experiments in media with different organic and inorganic nitrogen sources at different concentrations. Monitoring of growth, NO 3 - NO 2 - , NH 4 + concentration and N 2 O production revealed that B. azotoformans LMG 9581 T could not grow with NH 4 + as sole nitrogen source and confirmed the hypothesis of reduced nitrogen assimilation pathways. However, NH 4 + could be assimilated and contributed up to 50% of biomass if yeast extract was also provided. NH 4 + also had a significant but concentration-dependent influence on growth rate. The mechanisms behind these observations remain to be resolved but hypotheses for this deficiency in nitrogen assimilation are discussed. In addition, in all growth conditions tested a denitrification phenotype was observed, with all supplied NO 3 - converted to nitrous oxide (N 2 O).

  18. Effects of water stress on the distribution of 14C-assimilates in young apple trees (mauls pumila mill.)

    International Nuclear Information System (INIS)

    Dong Jiankang; Deng Ximin; Zeng Xiang

    1994-01-01

    Young apple trees were treated by water stress and 14 CO 2 was fed to leaves. Distribution of assimilates in source and sink organs was determined. The results show that plant water deficit increased the proportion of 14 C-assimilates remained in source leaves, and decreased the proportion of 13 C-assimilates exported into the developing fruits. Water stress also significantly decreased the photosynthetic rate of leaves and the growth rate of plants

  19. Assimilate partitioning during reproductive growth

    International Nuclear Information System (INIS)

    Finazzo, S.F.; Davenport, T.L.

    1987-01-01

    Leaves having various phyllotactic relationships to fruitlets were labeled for 1 hour with 10/sub r/Ci of 14 CO 2 . Fruitlets were also labeled. Fruitlets did fix 14 CO 2 . Translocation of radioactivity from the peel into the fruit occurred slowly and to a limited extent. No evidence of translocation out of the fruitlets was observed. Assimilate partitioning in avocado was strongly influenced by phyllotaxy. If a fruit and the labeled leaf had the same phyllotaxy then greater than 95% of the radiolabel was present in this fruit. When the fruit did not have the same phyllotaxy as the labeled leaf, the radiolabel distribution was skewed with 70% of the label going to a single adjacent position. Avocado fruitlets exhibit uniform labeling throughout a particular tissue. In avocado, assimilates preferentially move from leaves to fruits with the same phyllotaxy

  20. Growth analysis partitioning of assimilate in tomato plants cv. Micro-Tom submitted to nitrogen and pyraclostrobin

    Directory of Open Access Journals (Sweden)

    Emanuela Garbin Martinazzo

    2015-10-01

    Full Text Available This work aimed at comparing the growth and partitioning of assimilate in tomato plants cv. Micro-Tom subjected to nitrogen and pyraclostrobin. This substance favors the development of chloroplasts and the synthesis of chlorophyll. Tomato plants were submitted to the treatments: T1, complete nutrient solution without pyraclostrobin, T2, complete nutrient solution + pyraclostrobin, T3, ½ strength nutrient solution without N pyraclostrobin and T4, ½ strength nutrient solution N + pyraclostrobin. Plants were collected at regular intervals of seven days after transplantation throughout the crop cycle, with dry mass and leaf area being determined. From the primary data, growth analysis was carried out to calculate total dry matter (Wt, the instantaneous rates of dry matter production (Ct, relative growth (Rw e net assimilation (Ea, leaf area (Af, production rates (Ca and relative growth of leaf area index (Ra and leaf weight (Fw specific leaf area (Sa the dry matter partitioning between organs and number (Nfr and fresh fruit weight (Wfr. Plants of T1 showed higher Wt, Ct and Wfr compared to those of other treatments. However, the T2 plants exhibited similar Nfr to T1 plants, being superior to others. Also allocated on the total dry matter and at the end of the cycle, a higher percentage of dry matter in the seafood compared to T3 and T4 plants. Also they allocated relative to the total dry matter and at the end of the cycle, a higher percentage in fruits of plants to T3 and T4. The association between nitrogen and pyraclostrobin changes the growth and assimilated partition on tomato plants cv. Micro – Tom, and those submitted to ½ dose of nitrogen have a higher total dry matter and less final percentage of total dry matter in fruits , comparatively to those submitted to the association ½ dose of nitrogen and pyraclostrobin.

  1. Net Gain: A New Method for Preventing Malaria Deaths | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    A finely spun net could prevent as many as one-third of all child deaths in Africa, reports IDRC's new publication, Net Gain. Studies conducted in Gambia, Ghana, and Kenya show that the insecticide-treated mosquito net reduced the mortality rate of children under 5 years of age by up to 63 percent. Net Gain reviews and ...

  2. Planning of nets

    International Nuclear Information System (INIS)

    Carberry, M

    1996-01-01

    The paper is about the planning of nets in areas of low density like it is the case of the rural areas. The author includes economic and technological aspects, planning of nets, demands and management among others

  3. Annotating Coloured Petri Nets

    DEFF Research Database (Denmark)

    Lindstrøm, Bo; Wells, Lisa Marie

    2002-01-01

    Coloured Petri nets (CP-nets) can be used for several fundamentally different purposes like functional analysis, performance analysis, and visualisation. To be able to use the corresponding tool extensions and libraries it is sometimes necessary to include extra auxiliary information in the CP......-net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different uses...... of the same basic CP-net. One solution to this problem is that the auxiliary information is not integrated into colour sets and arc inscriptions of a CP-net, but is kept separately. This makes it easy to disable this auxiliary information if a CP-net is to be used for another purpose. This paper proposes...

  4. Naming game with biased assimilation over adaptive networks

    Science.gov (United States)

    Fu, Guiyuan; Zhang, Weidong

    2018-01-01

    The dynamics of two-word naming game incorporating the influence of biased assimilation over adaptive network is investigated in this paper. Firstly an extended naming game with biased assimilation (NGBA) is proposed. The hearer in NGBA accepts the received information in a biased manner, where he may refuse to accept the conveyed word from the speaker with a predefined probability, if the conveyed word is different from his current memory. Secondly, the adaptive network is formulated by rewiring the links. Theoretical analysis is developed to show that the population in NGBA will eventually reach global consensus on either A or B. Numerical simulation results show that the larger strength of biased assimilation on both words, the slower convergence speed, while larger strength of biased assimilation on only one word can slightly accelerate the convergence; larger population size can make the rate of convergence slower to a large extent when it increases from a relatively small size, while such effect becomes minor when the population size is large; the behavior of adaptively reconnecting the existing links can greatly accelerate the rate of convergence especially on the sparse connected network.

  5. Probability Maps for the Visualization of Assimilation Ensemble Flow Data

    KAUST Repository

    Hollt, Thomas

    2015-05-25

    Ocean forecasts nowadays are created by running ensemble simulations in combination with data assimilation techniques. Most of these techniques resample the ensemble members after each assimilation cycle. This means that in a time series, after resampling, every member can follow up on any of the members before resampling. Tracking behavior over time, such as all possible paths of a particle in an ensemble vector field, becomes very difficult, as the number of combinations rises exponentially with the number of assimilation cycles. In general a single possible path is not of interest but only the probabilities that any point in space might be reached by a particle at some point in time. In this work we present an approach using probability-weighted piecewise particle trajectories to allow such a mapping interactively, instead of tracing quadrillions of individual particles. We achieve interactive rates by binning the domain and splitting up the tracing process into the individual assimilation cycles, so that particles that fall into the same bin after a cycle can be treated as a single particle with a larger probability as input for the next time step. As a result we loose the possibility to track individual particles, but can create probability maps for any desired seed at interactive rates.

  6. Effects of a catheter-associated urinary tract infection prevention campaign on infection rate, catheter utilization, and health care workers' perspective at a community safety net hospital.

    Science.gov (United States)

    Gray, Dorinne; Nussle, Richard; Cruz, Abner; Kane, Gail; Toomey, Michael; Bay, Curtis; Ostovar, Gholamabbas Amin

    2016-01-01

    Preventing catheter-associated urinary tract infections is in the forefront of health care quality. However, nurse and physician engagement is a common barrier in infection prevention efforts. After implementation of a multidisciplinary catheter-associated urinary tract infection (CAUTI) prevention campaign, we studied the impact of our campaign and showed its association with reducing the CAUTI rate and catheter utilization and the positive effect on health care workers' engagement and perspectives. CAUTI prevention campaigns can lead to lower infection rates and change health care workers' perspective. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  7. Conditions for successful data assimilation

    Science.gov (United States)

    Morzfeld, M.; Chorin, A. J.

    2013-12-01

    Many applications in science and engineering require that the predictions of uncertain models be updated by information from a stream of noisy data. The model and the data jointly define a conditional probability density function (pdf), which contains all the information one has about the process of interest and various numerical methods can be used to study and approximate this pdf, e.g. the Kalman filter, variational methods or particle filters. Given a model and data, each of these algorithms will produce a result. We are interested in the conditions under which this result is reasonable, i.e. consistent with the real-life situation one is modeling. In particular, we show, using idealized models, that numerical data assimilation is feasible in principle only if a suitably defined effective dimension of the problem is not excessive. This effective dimension depends on the noise in the model and the data, and in physically reasonable problems it can be moderate even when the number of variables is huge. In particular, we find that the effective dimension being moderate induces a balance condition between the noises in the model and the data; this balance condition is often satisfied in realistic applications or else the noise levels are excessive and drown the underlying signal. We also study the effects of the effective dimension on particle filters in two instances, one in which the importance function is based on the model alone, and one in which it is based on both the model and the data. We have three main conclusions: (1) the stability (i.e., non-collapse of weights) in particle filtering depends on the effective dimension of the problem. Particle filters can work well if the effective dimension is moderate even if the true dimension is large (which we expect to happen often in practice). (2) A suitable choice of importance function is essential, or else particle filtering fails even when data assimilation is feasible in principle with a sequential algorithm

  8. Translocation and distribution of 14C-assimilation products in soybeans with different growth property

    International Nuclear Information System (INIS)

    Yoshida, Koichi; Gotoh, Kanji

    1975-01-01

    To 3 different kinds of soybeans, Tokachinagaha (Determinate), Koganejiro (Intermediate), and Harosoy (Indeterminate), 14 C was given at 3 stages of growth, namely, initial flowering, young pod development, and seed fattening periods. The 14 C assimilation efficiency, namely, the value of total 14 C assimilated divided by the area of the leaves which assimilated 14 C, was large when the leaf area was small. The value decreased with the increase of the leaf area. The rate of translocation of 14 C assimilation products was 20-50% in the period of initial flowering. The rate was highest in Tokachinagaha, followed by Koganejiro and Harosoy in this order. The difference was small in the period of young pod development. In the period of initial flowering, the distribution of 14 C to lower leaves and branches was high in Harosoy. In the period of young pod development, 30-40% of the assimilated 14 C was found in stems. This distribution is possibly due to temporary storage. In the period of seed fattening, 80-90% of the assimilated 14 C was present in pods and seeds. It was then concluded that the movement of assimilated products is high in the determinate type in the initial growth period. In the seed fattening period, the rate is high in the indeterminate type soy beans. (Fukutomi, T.)

  9. Estimating the net effect of progesterone elevation on the day of hCG on live birth rates after IVF: a cohort analysis of 3296 IVF cycles.

    Science.gov (United States)

    Venetis, Christos A; Kolibianakis, Efstratios M; Bosdou, Julia K; Lainas, George T; Sfontouris, Ioannis A; Tarlatzis, Basil C; Lainas, Tryfon G

    2015-03-01

    What is the proper way of assessing the effect of progesterone elevation (PE) on the day of hCG on live birth in women undergoing fresh embryo transfer after in vitro fertilization (IVF) using GnRH analogues and gonadotrophins? This study indicates that a multivariable approach, where the effect of the most important confounders is controlled for, can lead to markedly different results regarding the association between PE on the day of hCG and live birth rates after IVF when compared with the bivariate analysis that has been typically used in the relevant literature up to date. PE on the day of hCG is associated with decreased pregnancy rates in fresh IVF cycles. Evidence for this comes from observational studies that mostly failed to control for potential confounders. This is a retrospective analysis of a cohort of fresh IVF/intracytoplasmic sperm injection cycles (n = 3296) performed in a single IVF centre during the period 2001-2013. Patients in whom ovarian stimulation was performed with gonadotrophins and GnRH analogues. Natural cycles and cycles where stimulation involved the administration of clomiphene were excluded. In order to reflect routine clinical practice, no other exclusion criteria were imposed on this dataset. The primary outcome measure for this study was live birth defined as the delivery of a live infant after 24 weeks of gestation. We compared the association between PE on the day of hCG (defined as P > 1.5 ng/ml) and live birth rates calculated by simple bivariate analyses with that derived from multivariable logistic regression. The multivariable analysis controlled for female age, number of oocytes retrieved, number of embryos transferred, developmental stage of embryos at transfer (cleavage versus blastocyst), whether at least one good-quality embryo was transferred, the woman's body mass index, the total dose of FSH administered during ovarian stimulation and the type of GnRH analogues used (agonists versus antagonists) during ovarian

  10. Assimilation of remote sensing observations into a sediment transport model of China's largest freshwater lake: spatial and temporal effects.

    Science.gov (United States)

    Zhang, Peng; Chen, Xiaoling; Lu, Jianzhong; Zhang, Wei

    2015-12-01

    Numerical models are important tools that are used in studies of sediment dynamics in inland and coastal waters, and these models can now benefit from the use of integrated remote sensing observations. This study explores a scheme for assimilating remotely sensed suspended sediment (from charge-coupled device (CCD) images obtained from the Huanjing (HJ) satellite) into a two-dimensional sediment transport model of Poyang Lake, the largest freshwater lake in China. Optimal interpolation is used as the assimilation method, and model predictions are obtained by combining four remote sensing images. The parameters for optimal interpolation are determined through a series of assimilation experiments evaluating the sediment predictions based on field measurements. The model with assimilation of remotely sensed sediment reduces the root-mean-square error of the predicted sediment concentrations by 39.4% relative to the model without assimilation, demonstrating the effectiveness of the assimilation scheme. The spatial effect of assimilation is explored by comparing model predictions with remotely sensed sediment, revealing that the model with assimilation generates reasonable spatial distribution patterns of suspended sediment. The temporal effect of assimilation on the model's predictive capabilities varies spatially, with an average temporal effect of approximately 10.8 days. The current velocities which dominate the rate and direction of sediment transport most likely result in spatial differences in the temporal effect of assimilation on model predictions.

  11. Data Assimilation - Advances and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Brian J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-07-30

    This presentation provides an overview of data assimilation (model calibration) for complex computer experiments. Calibration refers to the process of probabilistically constraining uncertain physics/engineering model inputs to be consistent with observed experimental data. An initial probability distribution for these parameters is updated using the experimental information. Utilization of surrogate models and empirical adjustment for model form error in code calibration form the basis for the statistical methodology considered. The role of probabilistic code calibration in supporting code validation is discussed. Incorporation of model form uncertainty in rigorous uncertainty quantification (UQ) analyses is also addressed. Design criteria used within a batch sequential design algorithm are introduced for efficiently achieving predictive maturity and improved code calibration. Predictive maturity refers to obtaining stable predictive inference with calibrated computer codes. These approaches allow for augmentation of initial experiment designs for collecting new physical data. A standard framework for data assimilation is presented and techniques for updating the posterior distribution of the state variables based on particle filtering and the ensemble Kalman filter are introduced.

  12. Data assimilation with inequality constraints

    Science.gov (United States)

    Thacker, W. C.

    If values of variables in a numerical model are limited to specified ranges, these restrictions should be enforced when data are assimilated. The simplest option is to assimilate without regard for constraints and then to correct any violations without worrying about additional corrections implied by correlated errors. This paper addresses the incorporation of inequality constraints into the standard variational framework of optimal interpolation with emphasis on our limited knowledge of the underlying probability distributions. Simple examples involving only two or three variables are used to illustrate graphically how active constraints can be treated as error-free data when background errors obey a truncated multi-normal distribution. Using Lagrange multipliers, the formalism is expanded to encompass the active constraints. Two algorithms are presented, both relying on a solution ignoring the inequality constraints to discover violations to be enforced. While explicitly enforcing a subset can, via correlations, correct the others, pragmatism based on our poor knowledge of the underlying probability distributions suggests the expedient of enforcing them all explicitly to avoid the computationally expensive task of determining the minimum active set. If additional violations are encountered with these solutions, the process can be repeated. Simple examples are used to illustrate the algorithms and to examine the nature of the corrections implied by correlated errors.

  13. Expected Net Present Value, Expected Net Future Value, and the Ramsey Rule

    OpenAIRE

    Gollier, Christian

    2010-01-01

    Weitzman (1998) showed that when future interest rates are uncertain, using the expected net present value implies a term structure of discount rates that is decreasing to the smallest possible interest rate. On the contrary, using the expected net future value criteria implies an increasing term structure of discount rates up to the largest possible interest rate. We reconcile the two approaches by introducing risk aversion and utility maximization. We show that if the aggregate consumption ...

  14. Effect of Injecting Hydrogen Peroxide into Heavy Clay Loam Soil on Plant Water Status, NET CO2 Assimilation, Biomass, and Vascular Anatomy of Avocado Trees Efecto de la Inyección de Peróxido de Hidrógeno en Suelo Franco Arcilloso Pesado, sobre el Estado Hídrico, Asimilación Neta de CO2, Biomasa y Anatomía Vascular de Paltos

    Directory of Open Access Journals (Sweden)

    Pilar M Gil M

    2009-03-01

    Full Text Available In Chile, avocado (Persea americana Mill. orchards are often located in poorly drained, low-oxygen soils, situation which limits fruit production and quality. The objective of this study was to evaluate the effect of injecting soil with hydrogen peroxide (H2O2 as a source of molecular oxygen, on plant water status, net CO2 assimilation, biomass and anatomy of avocado trees set in clay loam soil with water content maintained at field capacity. Three-year-old ‘Hass’ avocado trees were planted outdoors in containers filled with heavy loam clay soil with moisture content sustained at field capacity. Plants were divided into two treatments, (a H2O2 injected into the soil through subsurface drip irrigation and (b soil with no H2O2 added (control. Stem and root vascular anatomical characteristics were determined for plants in each treatment in addition to physical soil characteristics, net CO2 assimilation (A, transpiration (T, stomatal conductance (gs, stem water potential (SWP, shoot and root biomass, water use efficiency (plant biomass per water applied [WUEb]. Injecting H2O2 into the soil significantly increased the biomass of the aerial portions of the plant and WUEb, but had no significant effect on measured A, T, gs, or SWP. Xylem vessel diameter and xylem/phloem ratio tended to be greater for trees in soil injected with H2O2 than for controls. The increased biomass of the aerial portions of plants in treated soil indicates that injecting H2O2 into heavy loam clay soils may be a useful management tool in poorly aerated soil.En Chile, los huertos de palto (Persea americana Mill. se ubican comúnmente en suelos pobremente drenados con bajo contenido de oxígeno, lo que limita producción y calidad de fruta. El objetivo de este estudio fue evaluar el efecto de la inyección de peróxido de hidrógeno (H2O2 al suelo como fuente de O2, sobre el estado hídrico, asimilación de CO2, biomasa y anatomía de paltos en suelo franco arcilloso con

  15. Quantum net dynamics

    International Nuclear Information System (INIS)

    Finkelstein, D.

    1989-01-01

    The quantum net unifies the basic principles of quantum theory and relativity in a quantum spacetime having no ultraviolet infinities, supporting the Dirac equation, and having the usual vacuum as a quantum condensation. A correspondence principle connects nets to Schwinger sources and further unifies the vertical structure of the theory, so that the functions of the many hierarchic levels of quantum field theory (predicate algebra, set theory, topology,hor-ellipsis, quantum dynamics) are served by one in quantum net dynamics

  16. Using the quantum yields of photosystem II and the rate of net photosynthesis to moniter high irradiance and temperature stress in chrysanthemum (Dendrantherma grandiflora)

    DEFF Research Database (Denmark)

    Janka, Eshetu; Körner, Oliver; Rosenqvist, Eva

    2015-01-01

    and quantum yield of PSII remaining low until the temperature reaches 28 °C and 2) the integration of online measurements to monitor photosynthesis and PSII operating efficiency may be used to optimise dynamic greenhouse control regimes by detecting plant stress caused by extreme microclimatic conditions.......Under a dynamic greenhouse climate control regime, temperature is adjusted to optimise plant physiological responses to prevailing irradiance levels; thus, both temperature and irradiance are used by the plant to maximise the rate of photosynthesis, assuming other factors are not limiting...... irradiance, the maximum Pn and ETR were reached at 24 °C. Increased irradiance decreased the PSII operating efficiency and increased NPQ, while both high irradiance and temperature had a significant effect on the PSII operating efficiency at temperatures >28 °C. Under high irradiance and temperature, changes...

  17. Programming NET Web Services

    CERN Document Server

    Ferrara, Alex

    2007-01-01

    Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET

  18. Game Coloured Petri Nets

    DEFF Research Database (Denmark)

    Westergaard, Michael

    2006-01-01

    This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment...

  19. Covariance Function for Nearshore Wave Assimilation Systems

    Science.gov (United States)

    2018-01-30

    which is applicable for any spectral wave model. The four dimensional variational (4DVar) assimilation methods are based on the mathematical ...covariance can be modeled by a parameterized Gaussian function, for nearshore wave assimilation applications , the covariance function depends primarily on...SPECTRAL ACTION DENSITY, RESPECTIVELY. ............................ 5 FIGURE 2. TOP ROW: STATISTICAL ANALYSIS OF THE WAVE-FIELD PROPERTIES AT THE

  20. Herbicides effect on the nitrogen fertilizer assimilation by sensitive plants

    International Nuclear Information System (INIS)

    Ladonin, V.F.; Samojlov, L.N.

    1976-01-01

    It has been established in studying the effect of herbicides on pea plants that the penetration of the preparations into the tissues of leaves and stems results in a slight increase of the rate of formation of dry substance in the leaves of the treated plants within 24 hours after treatment as compared with control, whereas in the last period of the analysis the herbicides strongly inhibit the formation of dry substance in leaves. The applied herbicide doses have resulted in drastic changes of the distribution of the plant-assimilated nitrogen between the protein and non-protein fractions in the leaves and stems of pea. When affected by the studied herbicides, the fertilizer nitrogen supply to the pea plants changes and the rate of the fertilizer nitrogen assimilation by the plants varies noticeably. The regularities of the fertilizer nitrogen inclusion in the protein and non-protein nitrogen compounds of the above-ground pea organs have been studied

  1. Data assimilation a mathematical introduction

    CERN Document Server

    Law, Kody; Zygalakis, Konstantinos

    2015-01-01

    This book provides a systematic treatment of the mathematical underpinnings of work in data assimilation, covering both theoretical and computational approaches. Specifically the authors develop a unified mathematical framework in which a Bayesian formulation of the problem provides the bedrock for the derivation, development and analysis of algorithms; the many examples used in the text, together with the algorithms which are introduced and discussed, are all illustrated by the MATLAB software detailed in the book and made freely available online. The book is organized into nine chapters: the first contains a brief introduction to the mathematical tools around which the material is organized; the next four are concerned with discrete time dynamical systems and discrete time data; the last four are concerned with continuous time dynamical systems and continuous time data and are organized analogously to the corresponding discrete time chapters. This book is aimed at mathematical researchers interested in a sy...

  2. Assimilation of diazotrophic nitrogen into pelagic food webs.

    Directory of Open Access Journals (Sweden)

    Ryan J Woodland

    Full Text Available The fate of diazotrophic nitrogen (N(D fixed by planktonic cyanobacteria in pelagic food webs remains unresolved, particularly for toxic cyanophytes that are selectively avoided by most herbivorous zooplankton. Current theory suggests that N(D fixed during cyanobacterial blooms can enter planktonic food webs contemporaneously with peak bloom biomass via direct grazing of zooplankton on cyanobacteria or via the uptake of bioavailable N(D (exuded from viable cyanobacterial cells by palatable phytoplankton or microbial consortia. Alternatively, N(D can enter planktonic food webs post-bloom following the remineralization of bloom detritus. Although the relative contribution of these processes to planktonic nutrient cycles is unknown, we hypothesized that assimilation of bioavailable N(D (e.g., nitrate, ammonium by palatable phytoplankton and subsequent grazing by zooplankton (either during or after the cyanobacterial bloom would be the primary pathway by which N(D was incorporated into the planktonic food web. Instead, in situ stable isotope measurements and grazing experiments clearly documented that the assimilation of N(D by zooplankton outpaced assimilation by palatable phytoplankton during a bloom of toxic Nodularia spumigena Mertens. We identified two distinct temporal phases in the trophic transfer of N(D from N. spumigena to the plankton community. The first phase was a highly dynamic transfer of N(D to zooplankton with rates that covaried with bloom biomass while bypassing other phytoplankton taxa; a trophic transfer that we infer was routed through bloom-associated bacteria. The second phase was a slowly accelerating assimilation of the dissolved-N(D pool by phytoplankton that was decoupled from contemporaneous variability in N. spumigena concentrations. These findings provide empirical evidence that N(D can be assimilated and transferred rapidly throughout natural plankton communities and yield insights into the specific processes

  3. Assimilation of diazotrophic nitrogen into pelagic food webs.

    Science.gov (United States)

    Woodland, Ryan J; Holland, Daryl P; Beardall, John; Smith, Jonathan; Scicluna, Todd; Cook, Perran L M

    2013-01-01

    The fate of diazotrophic nitrogen (N(D)) fixed by planktonic cyanobacteria in pelagic food webs remains unresolved, particularly for toxic cyanophytes that are selectively avoided by most herbivorous zooplankton. Current theory suggests that N(D) fixed during cyanobacterial blooms can enter planktonic food webs contemporaneously with peak bloom biomass via direct grazing of zooplankton on cyanobacteria or via the uptake of bioavailable N(D) (exuded from viable cyanobacterial cells) by palatable phytoplankton or microbial consortia. Alternatively, N(D) can enter planktonic food webs post-bloom following the remineralization of bloom detritus. Although the relative contribution of these processes to planktonic nutrient cycles is unknown, we hypothesized that assimilation of bioavailable N(D) (e.g., nitrate, ammonium) by palatable phytoplankton and subsequent grazing by zooplankton (either during or after the cyanobacterial bloom) would be the primary pathway by which N(D) was incorporated into the planktonic food web. Instead, in situ stable isotope measurements and grazing experiments clearly documented that the assimilation of N(D) by zooplankton outpaced assimilation by palatable phytoplankton during a bloom of toxic Nodularia spumigena Mertens. We identified two distinct temporal phases in the trophic transfer of N(D) from N. spumigena to the plankton community. The first phase was a highly dynamic transfer of N(D) to zooplankton with rates that covaried with bloom biomass while bypassing other phytoplankton taxa; a trophic transfer that we infer was routed through bloom-associated bacteria. The second phase was a slowly accelerating assimilation of the dissolved-N(D) pool by phytoplankton that was decoupled from contemporaneous variability in N. spumigena concentrations. These findings provide empirical evidence that N(D) can be assimilated and transferred rapidly throughout natural plankton communities and yield insights into the specific processes underlying

  4. Effective assimilation of global precipitation: simulation experiments

    Directory of Open Access Journals (Sweden)

    Guo-Yuan Lien

    2013-07-01

    Full Text Available Past attempts to assimilate precipitation by nudging or variational methods have succeeded in forcing the model precipitation to be close to the observed values. However, the model forecasts tend to lose their additional skill after a few forecast hours. In this study, a local ensemble transform Kalman filter (LETKF is used to effectively assimilate precipitation by allowing ensemble members with better precipitation to receive higher weights in the analysis. In addition, two other changes in the precipitation assimilation process are found to alleviate the problems related to the non-Gaussianity of the precipitation variable: (a transform the precipitation variable into a Gaussian distribution based on its climatological distribution (an approach that could also be used in the assimilation of other non-Gaussian observations and (b only assimilate precipitation at the location where at least some ensemble members have precipitation. Unlike many current approaches, both positive and zero rain observations are assimilated effectively. Observing system simulation experiments (OSSEs are conducted using the Simplified Parametrisations, primitivE-Equation DYnamics (SPEEDY model, a simplified but realistic general circulation model. When uniformly and globally distributed observations of precipitation are assimilated in addition to rawinsonde observations, both the analyses and the medium-range forecasts of all model variables, including precipitation, are significantly improved as compared to only assimilating rawinsonde observations. The effect of precipitation assimilation on the analyses is retained on the medium-range forecasts and is larger in the Southern Hemisphere (SH than that in the Northern Hemisphere (NH because the NH analyses are already made more accurate by the denser rawinsonde stations. These improvements are much reduced when only the moisture field is modified by the precipitation observations. Both the Gaussian transformation and

  5. Bias Correction for Assimilation of Retrieved AIRS Profiles of Temperature and Humidity

    Science.gov (United States)

    Blakenship, Clay; Zavodsky, Bradley; Blackwell, William

    2014-01-01

    The Atmospheric Infrared Sounder (AIRS) is a hyperspectral radiometer aboard NASA's Aqua satellite designed to measure atmospheric profiles of temperature and humidity. AIRS retrievals are assimilated into the Weather Research and Forecasting (WRF) model over the North Pacific for some cases involving "atmospheric rivers". These events bring a large flux of water vapor to the west coast of North America and often lead to extreme precipitation in the coastal mountain ranges. An advantage of assimilating retrievals rather than radiances is that information in partly cloudy fields of view can be used. Two different Level 2 AIRS retrieval products are compared: the Version 6 AIRS Science Team standard retrievals and a neural net retrieval from MIT. Before assimilation, a bias correction is applied to adjust each layer of retrieved temperature and humidity so the layer mean values agree with a short-term model climatology. WRF runs assimilating each of the products are compared against each other and against a control run with no assimilation. Forecasts are against ERA reanalyses.

  6. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1991-01-01

    This paper describes how Coloured Petri Nets (CP-nets) have been developed — from being a promising theoretical model to being a full-fledged language for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and...

  7. Net zero water

    CSIR Research Space (South Africa)

    Lindeque, M

    2013-01-01

    Full Text Available the national grid. The unfortunate situation with water is that there is no replacement technology for water. Water can be supplied from many different sources. A net zero energy development will move closer to a net zero water development by reducing...

  8. Construction of monophase nets

    International Nuclear Information System (INIS)

    Suarez A, Jose Antonio

    1996-01-01

    The paper refers to the use of monophase loads in commercial residential urbanizations and in small industries, for this reason it is considered unnecessary the construction of three-phase nets. The author makes a historical recount of these nets in Bogota, his capacities, uses and energy savings

  9. The Assimilation of Diazotroph-Derived Nitrogen by Scleractinian Corals Depends on Their Metabolic Status

    Directory of Open Access Journals (Sweden)

    Vanessa N. Bednarz

    2017-01-01

    Full Text Available Tropical corals are associated with a diverse community of dinitrogen (N2-fixing prokaryotes (diazotrophs providing the coral an additional source of bioavailable nitrogen (N in oligotrophic waters. The overall activity of these diazotrophs changes depending on the current environmental conditions, but to what extent it affects the assimilation of diazotroph-derived N (DDN by corals is still unknown. Here, in a series of 15N2 tracer experiments, we directly quantified DDN assimilation by scleractinian corals from the Red Sea exposed to different environmental conditions. We show that DDN assimilation strongly varied with the corals’ metabolic status or with phosphate availability in the water. The very autotrophic shallow-water (~5 m corals showed low or no DDN assimilation, which significantly increased under elevated phosphate availability (3 µM. Corals that depended more on heterotrophy (i.e., bleached and deep-water [~45 m] corals assimilated significantly more DDN, which contributed up to 15% of the corals’ N demand (compared to 1% in shallow corals. Furthermore, we demonstrate that a substantial part of the DDN assimilated by deep corals was likely obtained from heterotrophic feeding on fixed N compounds and/or diazotrophic cells in the mucus. Conversely, in shallow corals, the net release of mucus, rich in organic carbon compounds, likely enhanced diazotroph abundance and activity and thereby the release of fixed N to the pelagic and benthic reef community. Overall, our results suggest that DDN assimilation by corals varies according to the environmental conditions and is likely linked to the capacity of the coral to acquire nutrients from seawater.

  10. Presence of animal feeding operations and community socioeconomic factors impact salmonellosis incidence rates: An ecological analysis using data from the Foodborne Diseases Active Surveillance Network (FoodNet), 2004-2010.

    Science.gov (United States)

    Shaw, Kristi S; Cruz-Cano, Raul; Jiang, Chengsheng; Malayil, Leena; Blythe, David; Ryan, Patricia; Sapkota, Amy R

    2016-10-01

    Nontyphoidal Salmonella spp. are a leading cause of foodborne illness. Risk factors for salmonellosis include the consumption of contaminated chicken, eggs, pork and beef. Agricultural, environmental and socioeconomic factors also have been associated with rates of Salmonella infection. However, to our knowledge, these factors have not been modeled together at the community-level to improve our understanding of whether rates of salmonellosis are variable across communities defined by differing factors. To address this knowledge gap, we obtained data on culture-confirmed Salmonella Typhimurium, S. Enteritidis, S. Newport and S. Javiana cases (2004-2010; n=14,297) from the Foodborne Diseases Active Surveillance Network (FoodNet), and socioeconomic, environmental and agricultural data from the 2010 Census of Population and Housing, the 2011 American Community Survey, and the 2007 U.S. Census of Agriculture. We linked data by zip code and derived incidence rate ratios using negative binomial regressions. Multiple community-level factors were associated with salmonellosis rates; however, our findings varied by state. For example, in Georgia (Incidence Rate Ratio (IRR)=1.01; 95% Confidence Interval (CI)=1.005-1.015) Maryland (IRR=1.01; 95% CI=1.003-1.015) and Tennessee (IRR=1.01; 95% CI=1.002-1.012), zip codes characterized by greater rurality had higher rates of S. Newport infections. The presence of broiler chicken operations, dairy operations and cattle operations in a zip code also was associated with significantly higher rates of infection with at least one serotype in states that are leading producers of these animal products. For instance, in Georgia and Tennessee, rates of S. Enteritidis infection were 48% (IRR=1.48; 95% CI=1.12-1.95) and 46% (IRR=1.46; 95% CI=1.17-1.81) higher in zip codes with broiler chicken operations compared to those without these operations. In Maryland, New Mexico and Tennessee, higher poverty levels in zip codes were associated with

  11. Fusion through the NET

    International Nuclear Information System (INIS)

    Spears, B.

    1987-01-01

    The paper concerns the next generation of fusion machines which are intended to demonstrate the technical viability of fusion. In Europe, the device that will follow on from JET is known as NET - the Next European Torus. If the design programme for NET proceeds, Europe could start to build the machine in 1994. The present JET programme hopes to achieve breakeven in the early 1990's. NET hopes to reach ignition in the next century, and so lay the foundation for a demonstration reactor. A description is given of the technical specifications of the components of NET, including: the first wall, the divertors to protect the wall, the array of magnets that provide the fields containing the plasma, the superconducting magnets, and the shield of the machine. NET's research programme is briefly outlined, including the testing programme to optimise conditions in the machine to achieve ignition, and its safety work. (U.K.)

  12. Skill Assessment in Ocean Biological Data Assimilation

    Science.gov (United States)

    Gregg, Watson W.; Friedrichs, Marjorie A. M.; Robinson, Allan R.; Rose, Kenneth A.; Schlitzer, Reiner; Thompson, Keith R.; Doney, Scott C.

    2008-01-01

    There is growing recognition that rigorous skill assessment is required to understand the ability of ocean biological models to represent ocean processes and distributions. Statistical analysis of model results with observations represents the most quantitative form of skill assessment, and this principle serves as well for data assimilation models. However, skill assessment for data assimilation requires special consideration. This is because there are three sets of information in the free-run model, data, and the assimilation model, which uses Data assimilation information from both the flee-run model and the data. Intercom parison of results among the three sets of information is important and useful for assessment, but is not conclusive since the three information sets are intertwined. An independent data set is necessary for an objective determination. Other useful measures of ocean biological data assimilation assessment include responses of unassimilated variables to the data assimilation, performance outside the prescribed region/time of interest, forecasting, and trend analysis. Examples of each approach from the literature are provided. A comprehensive list of ocean biological data assimilation and their applications of skill assessment, in both ecosystem/biogeochemical and fisheries efforts, is summarized.

  13. Methodological Developments in Geophysical Assimilation Modeling

    Science.gov (United States)

    Christakos, George

    2005-06-01

    This work presents recent methodological developments in geophysical assimilation research. We revisit the meaning of the term "solution" of a mathematical model representing a geophysical system, and we examine its operational formulations. We argue that an assimilation solution based on epistemic cognition (which assumes that the model describes incomplete knowledge about nature and focuses on conceptual mechanisms of scientific thinking) could lead to more realistic representations of the geophysical situation than a conventional ontologic assimilation solution (which assumes that the model describes nature as is and focuses on form manipulations). Conceptually, the two approaches are fundamentally different. Unlike the reasoning structure of conventional assimilation modeling that is based mainly on ad hoc technical schemes, the epistemic cognition approach is based on teleologic criteria and stochastic adaptation principles. In this way some key ideas are introduced that could open new areas of geophysical assimilation to detailed understanding in an integrated manner. A knowledge synthesis framework can provide the rational means for assimilating a variety of knowledge bases (general and site specific) that are relevant to the geophysical system of interest. Epistemic cognition-based assimilation techniques can produce a realistic representation of the geophysical system, provide a rigorous assessment of the uncertainty sources, and generate informative predictions across space-time. The mathematics of epistemic assimilation involves a powerful and versatile spatiotemporal random field theory that imposes no restriction on the shape of the probability distributions or the form of the predictors (non-Gaussian distributions, multiple-point statistics, and nonlinear models are automatically incorporated) and accounts rigorously for the uncertainty features of the geophysical system. In the epistemic cognition context the assimilation concept may be used to

  14. Effect of climate warming on the annual terrestrial net ecosystem CO2 exchange globally in the boreal and temperate regions.

    Science.gov (United States)

    Zhang, Zhiyuan; Zhang, Renduo; Cescatti, Alessandro; Wohlfahrt, Georg; Buchmann, Nina; Zhu, Juan; Chen, Guanhong; Moyano, Fernando; Pumpanen, Jukka; Hirano, Takashi; Takagi, Kentaro; Merbold, Lutz

    2017-06-08

    The net ecosystem CO 2 exchange is the result of the imbalance between the assimilation process (gross primary production, GPP) and ecosystem respiration (RE). The aim of this study was to investigate temperature sensitivities of these processes and the effect of climate warming on the annual terrestrial net ecosystem CO 2 exchange globally in the boreal and temperate regions. A database of 403 site-years of ecosystem flux data at 101 sites in the world was collected and analyzed. Temperature sensitivities of rates of RE and GPP were quantified with Q 10 , defined as the increase of RE (or GPP) rates with a temperature rise of 10 °C. Results showed that on the annual time scale, the intrinsic temperature sensitivity of GPP (Q 10sG ) was higher than or equivalent to the intrinsic temperature sensitivity of RE (Q 10sR ). Q 10sG was negatively correlated to the mean annual temperature (MAT), whereas Q 10sR was independent of MAT. The analysis of the current temperature sensitivities and net ecosystem production suggested that temperature rise might enhance the CO 2 sink of terrestrial ecosystems both in the boreal and temperate regions. In addition, ecosystems in these regions with different plant functional types should sequester more CO 2 with climate warming.

  15. Acclimation to higher VPD and temperature minimized negative effects on assimilation and grain yield of wheat

    DEFF Research Database (Denmark)

    Rashid, Muhammad Adil; Andersen, Mathias Neumann; Wollenweber, Bernd

    2018-01-01

    Adapting to climate change and minimizing its negative impact on crop production requires detailed understanding of the direct and indirect effects of different climate variables (i.e. temperature, VPD). We investigated the direct (via heat stress) and indirect effects (through increased VPD....... Treatments included hot humid (HH: 36° C; 1.96 kPa VPD), hot dry (HD: 36° C; 3.92 kPa VPD) and normal (NC: 24° C; 1.49 kPa VPD). Difference between HH and HD was considered as the indirect effect of temperature through increased VPD. HD increased transpiration by 2–22% and decreased photosynthetic water......-use efficiency (WUEp) by 24–64% over HH during stress but whole-plant WUE at final harvest was not affected. HD reduced grainfilling duration (3 days), resulted in relatively lower green leaf area (GLA) after the stress and showed a tendency of lower net assimilation rate during the stress compared to HH...

  16. A mechanistic modeling and data assimilation framework for Mojave Desert ecohydrology

    Science.gov (United States)

    Ng, Gene-Hua Crystal.; Bedford, David; Miller, David

    2014-01-01

    This study demonstrates and addresses challenges in coupled ecohydrological modeling in deserts, which arise due to unique plant adaptations, marginal growing conditions, slow net primary production rates, and highly variable rainfall. We consider model uncertainty from both structural and parameter errors and present a mechanistic model for the shrub Larrea tridentata (creosote bush) under conditions found in the Mojave National Preserve in southeastern California (USA). Desert-specific plant and soil features are incorporated into the CLM-CN model by Oleson et al. (2010). We then develop a data assimilation framework using the ensemble Kalman filter (EnKF) to estimate model parameters based on soil moisture and leaf-area index observations. A new implementation procedure, the “multisite loop EnKF,” tackles parameter estimation difficulties found to affect desert ecohydrological applications. Specifically, the procedure iterates through data from various observation sites to alleviate adverse filter impacts from non-Gaussianity in small desert vegetation state values. It also readjusts inconsistent parameters and states through a model spin-up step that accounts for longer dynamical time scales due to infrequent rainfall in deserts. Observation error variance inflation may also be needed to help prevent divergence of estimates from true values. Synthetic test results highlight the importance of adequate observations for reducing model uncertainty, which can be achieved through data quality or quantity.

  17. A mechanistic modeling and data assimilation framework for Mojave Desert ecohydrology

    Science.gov (United States)

    Ng, Gene-Hua Crystal; Bedford, David R.; Miller, David M.

    2014-06-01

    This study demonstrates and addresses challenges in coupled ecohydrological modeling in deserts, which arise due to unique plant adaptations, marginal growing conditions, slow net primary production rates, and highly variable rainfall. We consider model uncertainty from both structural and parameter errors and present a mechanistic model for the shrub Larrea tridentata (creosote bush) under conditions found in the Mojave National Preserve in southeastern California (USA). Desert-specific plant and soil features are incorporated into the CLM-CN model by Oleson et al. (2010). We then develop a data assimilation framework using the ensemble Kalman filter (EnKF) to estimate model parameters based on soil moisture and leaf-area index observations. A new implementation procedure, the "multisite loop EnKF," tackles parameter estimation difficulties found to affect desert ecohydrological applications. Specifically, the procedure iterates through data from various observation sites to alleviate adverse filter impacts from non-Gaussianity in small desert vegetation state values. It also readjusts inconsistent parameters and states through a model spin-up step that accounts for longer dynamical time scales due to infrequent rainfall in deserts. Observation error variance inflation may also be needed to help prevent divergence of estimates from true values. Synthetic test results highlight the importance of adequate observations for reducing model uncertainty, which can be achieved through data quality or quantity.

  18. Data Assimilation with Optimal Maps

    Science.gov (United States)

    El Moselhy, T.; Marzouk, Y.

    2012-12-01

    Tarek El Moselhy and Youssef Marzouk Massachusetts Institute of Technology We present a new approach to Bayesian inference that entirely avoids Markov chain simulation and sequential importance resampling, by constructing a map that pushes forward the prior measure to the posterior measure. Existence and uniqueness of a suitable measure-preserving map is established by formulating the problem in the context of optimal transport theory. The map is written as a multivariate polynomial expansion and computed efficiently through the solution of a stochastic optimization problem. While our previous work [1] focused on static Bayesian inference problems, we now extend the map-based approach to sequential data assimilation, i.e., nonlinear filtering and smoothing. One scheme involves pushing forward a fixed reference measure to each filtered state distribution, while an alternative scheme computes maps that push forward the filtering distribution from one stage to the other. We compare the performance of these schemes and extend the former to problems of smoothing, using a map implementation of the forward-backward smoothing formula. Advantages of a map-based representation of the filtering and smoothing distributions include analytical expressions for posterior moments and the ability to generate arbitrary numbers of independent uniformly-weighted posterior samples without additional evaluations of the dynamical model. Perhaps the main advantage, however, is that the map approach inherently avoids issues of sample impoverishment, since it explicitly represents the posterior as the pushforward of a reference measure, rather than with a particular set of samples. The computational complexity of our algorithm is comparable to state-of-the-art particle filters. Moreover, the accuracy of the approach is controlled via the convergence criterion of the underlying optimization problem. We demonstrate the efficiency and accuracy of the map approach via data assimilation in

  19. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Gustavsen, Arild

    2010-01-01

    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...

  20. Getting to Net Zero

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.

  1. Pro NET Best Practices

    CERN Document Server

    Ritchie, Stephen D

    2011-01-01

    Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and

  2. Data assimilation in the early phase: Kalman filtering RIMPUFF

    International Nuclear Information System (INIS)

    Astrup, P.; Turcanu, C.; Puch, R.O.; Palma, C.R.; Mikkelsen, T.

    2004-09-01

    In the framework of the DAONEM project (Data Assimilation for Off-site Nuclear Emergency Management), a data assimilation module, ADUM (Atmospheric Dispersion Updating Module), for the mesoscale atmospheric dispersion program RIMPUFF (Risoe Mesoscale Puff model) part of the early-phase programs of RODOS (Realtime Online DecisiOn Support system for nuclear emergencies) has been developed. It is built on the Kalman filtering algorithm and it assimilates 10-minute averaged gamma dose rates measured at ground level stations. Since the gamma rates are non-linear functions of the state vector variables, the applied Kalman filter is the so-called Extended Kalman filter. In more ways the implementation is non standard: 1) the number of state vector variables varies with time, and 2) the state vector variables are prediction updated with 1-minute time steps but only Kalman filtered every 10 minutes, and this based on time averaged measurements. Given reasonable conditions, i.e. a spatially dense distribution of gamma monitors and a realistic wind field, the developed ADUM module is found to be able to enhance the prediction of the gamma dose field. Based on some of the Kalman filtering parameters, another module, ToDeMM, has been developed for providing the late-phase DeMM (Deposition Monitoring Module) of RODOS with an ensemble of fields of ground level air concentrations and wet deposited material. This accounts for the uncertainty estimation of this kind of quantities as calculated by RIMPUFF for use by DeMM. (au)

  3. Investigation of glycerol assimilation and cofactor metabolism in Lactococcus lactis

    DEFF Research Database (Denmark)

    Holm, Anders Koefoed

    of glycerol kinase from L. lactis, introduction of a heterologous glycerol assimilation pathway and construction of a library of NADH oxidase activity. Based on a preliminary analysis of transcription level data, an attempt was made to stimulate glycerol assimilation by overexpressing the glycerol kinase...... already present in L. lactis. The construction and verification of a strain with increased glycerol kinase activity was not fully completed and is still ongoing. Similarly the construction of mutants expressing a heterologous pathway for glycerol dissimilation is also an ongoing task. An artificial...... effects and improve the growth rate, though not completely to the level of the reference strain. The fact that this effect was predominantly observed while utilizing xylose implicates the involvement of the pentose phosphate pathway. A possible mechanism underlying the observed growth characteristics...

  4. CO2 assimilation in the chemocline of Lake Cadagno is dominated by a few types of phototrophic purple sulfur bacteria

    DEFF Research Database (Denmark)

    Storelli, Nicola; Peduzzi, Sandro; Saad, Maged

    2013-01-01

    % of the total primary production in the chemocline. Pure cultures of strain Cad16(T) exposed to cycles of 12 h of light and 12 h of darkness exhibited the highest CO₂ assimilation during the first 4 h of light. The draft genome sequence of Cad16(T) showed the presence of cbbL and cbbM genes, which encode form I...... bacterium Candidatus 'Thiodictyon syntrophicum' strain Cad16(T) had the highest CO₂ assimilation rate in the light of the four strains tested and had a high CO₂ assimilation rate even in the dark. The CO₂ assimilation of the population represented by strain Cad16(T) was estimated to be up to 25...... not correlate with the peaks in CO₂ assimilation....

  5. The importance of peers: assimilation patterns among second-generation Turkish immigrants in Western Europe

    NARCIS (Netherlands)

    Ali, S.; Fokkema, C.M.

    2011-01-01

    The two dominant approaches to immigrant assimilation, segmented assimilation and "new" assimilation theories, have been successful at reporting and analyzing between-group differences in assimilation patterns. However, studies of assimilation generally do not address differences at the individual

  6. PhysioNet

    Data.gov (United States)

    U.S. Department of Health & Human Services — The PhysioNet Resource is intended to stimulate current research and new investigations in the study of complex biomedical and physiologic signals. It offers free...

  7. Blanket testing in NET

    International Nuclear Information System (INIS)

    Chazalon, M.; Daenner, W.; Libin, B.

    1989-01-01

    The testing stages in NET for the performance assessment of the various breeding blanket concepts developed at the present time in Europe for DEMO (LiPb and ceramic blankets) and the requirements upon NET to perform these tests are reviewed. Typical locations available in NET for blanket testing are the central outboard segments and the horizontal ports of in-vessel sectors. These test positions will be connectable with external test loops. The number of test loops (helium, water, liquid metal) will be such that each major class of blankets can be tested in NET. The test positions, the boundary conditions and the external test loops are identified and the requirements for test blankets are summarized (author). 6

  8. Assimilative and non-assimilative color spreading in the watercolor configuration

    Directory of Open Access Journals (Sweden)

    Eiji eKimura

    2014-09-01

    Full Text Available A colored line flanking a darker contour will appear to spread its color onto an area enclosed by the line (watercolor effect. The watercolor effect has been characterized as an assimilative effect, but non-assimilative color spreading has also been demonstrated in the same spatial configuration; e.g., when a black inner contour (IC is paired with a blue outer contour (OC, yellow color spreading can be observed. To elucidate visual mechanisms underlying these different color spreading effects, this study investigated the effects of luminance ratio between the double contours on the induced color by systematically manipulating the IC and OC luminances (Experiment 1 as well as the background luminance (Experiment 2. The results showed that the luminance conditions suitable for assimilative and non-assimilative color spreading were nearly opposite. When the Weber contrast of the IC to the background luminances (IC contrast was smaller than that of the OC (OC contrast, the induced color became similar to the IC color (assimilative spreading. In contrast, when the OC contrast was smaller than or equal to the IC contrast, the induced color became yellow (non-assimilative spreading. Extending these findings, Experiment 3 showed that bilateral color spreading, e.g., assimilative spreading on one side and non-assimilative spreading on the other side, can also be observed in the watercolor configuration. These results suggest that the assimilative and non-assimilative spreading were mediated by different visual mechanisms. The properties of the assimilative spreading are consistent with the model proposed to account for neon color spreading [Grossberg, S. & Mingolla, E. (1985 Percept. Psychophys., 38, 141-171] and extended for the watercolor effect [Pinna, B., & Grossberg, S. (2005 J. Opt. Soc. Am. A, 22, 2207-2221]. However, the present results suggest that additional mechanisms are needed to account for the non-assimilative color spreading.

  9. Assimilative and non-assimilative color spreading in the watercolor configuration.

    Science.gov (United States)

    Kimura, Eiji; Kuroki, Mikako

    2014-01-01

    A colored line flanking a darker contour will appear to spread its color onto an area enclosed by the line (watercolor effect). The watercolor effect has been characterized as an assimilative effect, but non-assimilative color spreading has also been demonstrated in the same spatial configuration; e.g., when a black inner contour (IC) is paired with a blue outer contour (OC), yellow color spreading can be observed. To elucidate visual mechanisms underlying these different color spreading effects, this study investigated the effects of luminance ratio between the double contours on the induced color by systematically manipulating the IC and the OC luminance (Experiment 1) as well as the background luminance (Experiment 2). The results showed that the luminance conditions suitable for assimilative and non-assimilative color spreading were nearly opposite. When the Weber contrast of the IC to the background luminance (IC contrast) was smaller in size than that of the OC (OC contrast), the induced color became similar to the IC color (assimilative spreading). In contrast, when the OC contrast was smaller than or equal to the IC contrast, the induced color became yellow (non-assimilative spreading). Extending these findings, Experiment 3 showed that bilateral color spreading, i.e., assimilative spreading on one side and non-assimilative spreading on the other side, can also be observed in the watercolor configuration. These results suggest that the assimilative and the non-assimilative spreading were mediated by different visual mechanisms. The properties of the assimilative spreading are consistent with the model proposed to account for neon color spreading (Grossberg and Mingolla, 1985) and extended for the watercolor effect (Pinna and Grossberg, 2005). However, the present results suggest that additional mechanisms are needed to account for the non-assimilative color spreading.

  10. Error Covariance Estimation of Mesoscale Data Assimilation

    National Research Council Canada - National Science Library

    Xu, Qin

    2005-01-01

    The goal of this project is to explore and develop new methods of error covariance estimation that will provide necessary statistical descriptions of prediction and observation errors for mesoscale data assimilation...

  11. ERP ASSIMILATION: AN END-USER APPROACH

    Directory of Open Access Journals (Sweden)

    Hurbean Luminita

    2013-07-01

    The paper discusses the ERP adoption based on the IT assimilation theory. The ERP lifecycle is associated with the IT assimilation steps. We propose a distribution of these steps along the lifecycle. Derived from the findings in the reviewed literature we will focus the cultural factors, in particular those related to the end-users (determined as a major impact factor in our previous study: Negovan et al., 2011. Our empirical study is centred on the end-users perspective and it tries to determine if and how their behaviour affects the achievement of the ERP assimilation steps. The paper reasons that organizations that understand the IT assimilation steps correlated to the ERP implementation critical factors are more likely to implement and use ERP successfully.

  12. Net Community and Gross Photosynthetic Production Rates in the Eastern Tropical South Pacific, as Determined from O2/AR Ratios and Triple Oxygen Isotopic Composition of Dissolved O2

    Science.gov (United States)

    Prokopenko, M. G.; Yeung, L. Y.; Berelson, W.; Fleming, J.; Rollins, N.; Young, E. D.; Haskell, W. Z.; Hammond, D. E.; Capone, D. G.

    2010-12-01

    This study assesses the rates of ocean carbon production and its fate with respect to recycling or export in the Eastern Tropical South Pacific (ETSP). ETSP has been previously identified as a region where N2 fixation and denitrification may be spatially coupled; this is also a region of localized CO2 outgassing. Using an Equilibrated Inlet Mass Spectrometer (EIMS) system, we obtained continuous measurements of the biological O2 supersaturation in the mixed layer along the ship track encompassing a region bounded by 10-20° S and 80-100° W in January - March, 2010. Vertical profiles were also taken at selected stations and analyzed for dissolved O2/Ar ratios on EIMS and triple oxygen isotope composition (17O excess) on a multi-collector IRMS (Isotope Ratio Mass Spectrometer) at UCLA. Gas exchange rates were estimated using two approaches: the Rn-222 deficit method and the wind parameterization method, which utilized wind speeds extracted from ASCAT satellite database. Oxygen Net Community Production (O-NCP) rates calculated based on biological O2 supersaturation ranged from slightly negative to ~ 0.3 - 15 mmol/m2d, with higher rates along the northern part of the transect. Oxygen Gross Community Production (O-GPP) rates calculated from 17O excess were between 50 ± 20 and 200 ± 40 mmol/m2d, with higher rates observed along the northern cruise transect as well. Notably, the NCP/GPP ratios along the northern transect were higher by the factor of 2 to 3 than their southern counterparts. The O2/Ar-based NCP rates were comparable to POC flux measured with floating traps deployed at the southern stations, but exceeded by a factor of 5-10 the trap POC fluxes obtained at the northern stations. A one-dimensional box model has been constructed to quantify the magnitude of oxygen primary production below the mixed layer. The results of this work will be integrated with measurements of 15-N2 uptake that are in progress, to constrain the potential contribution of N2 fixation

  13. Programming NET 35

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "

  14. NET SALARY ADJUSTMENT

    CERN Multimedia

    Finance Division

    2001-01-01

    On 15 June 2001 the Council approved the correction of the discrepancy identified in the net salary adjustment implemented on 1st January 2001 by retroactively increasing the scale of basic salaries to achieve the 2.8% average net salary adjustment approved in December 2000. We should like to inform you that the corresponding adjustment will be made to your July salary. Full details of the retroactive adjustments will consequently be shown on your pay slip.

  15. Data assimilation in the hydrological dispersion module of Rodos

    International Nuclear Information System (INIS)

    Madsen, H.

    2003-01-01

    Full text: The Hydrological Dispersion Module (HDM) of the Real Time On-line Decision Support System for Nuclear Emergencies in Europe (RODOS) simulates the transport and dispersion of radionuclides in the aquatic environment. This includes wash-off from watersheds following an atmospheric deposition as well as direct releases and transport and sedimentation in rivers, lakes and reservoirs. The output from the HDM is used by the aquatic food and dose module in RODOS for calculating the transfer of radionuclides to man and the resulting radiation exposure. A data assimilation system is presently being developed for the HDM that effectively combines the numerical models with radionuclide measurements in order to improve the capabilities for prediction of radionuclide contamination of the aquatic environment. In addition, the data assimilation system offers a consistent framework for addressing model and measurement uncertainties and quantifying the resulting prediction uncertainty of the radionuclide contamination. The system will provide decision makers with more accurate forecasts of the radionuclide contamination as well as the associated uncertainty, and hence provide the basis for more efficient emergency management. One of the main uncertainties in the modelling of radionuclide wash-off from watersheds is related to the concentration and spatial distribution of the radionuclide deposition. In addition, for key model parameters such as wash-off coefficients, partition coefficients, and exchange rates for the 'water - suspended sediment' and 'suspended sediment - bottom layer' systems only rough and highly uncertain estimates can be given which introduce additional uncertainties. In the case of direct release into the water bodies, the uncertainty of the release rate will further add to the model prediction uncertainty. The deposition and the associated uncertainty are obtained from the Deposition Monitoring Module (DeMM). Thus, when gamma dose rate measurements

  16. Impact of GPM Rainrate Data Assimilation on Simulation of Hurricane Harvey (2017)

    Science.gov (United States)

    Li, Xuanli; Srikishen, Jayanthi; Zavodsky, Bradley; Mecikalski, John

    2018-01-01

    Built upon Tropical Rainfall Measuring Mission (TRMM) legacy for next-generation global observation of rain and snow. The GPM was launched in February 2014 with Dual-frequency Precipitation Radar (DPR) and GPM Microwave Imager (GMI) onboard. The GPM has a broad global coverage approximately 70deg S -70deg N with a swath of 245/125-km for the Ka (35.5 GHz)/Ku (13.6 GHz) band radar, and 850-km for the 13-channel GMI. GPM also features better retrievals for heavy, moderate, and light rain and snowfall To develop methodology to assimilate GPM surface precipitation data with Grid-point Statistical Interpolation (GSI) data assimilation system and WRF ARW model To investigate the potential and the value of utilizing GPM observation into NWP for operational environment The GPM rain rate data has been successfully assimilated using the GSI rain data assimilation package. Impacts of rain rate data have been found in temperature and moisture fields of initial conditions. 2.Assimilation of either GPM IMERG or GPROF rain product produces significant improvement in precipitation amount and structure for Hurricane Harvey (2017) forecast. Since IMERG data is available half-hourly, further forecast improvement is expected with continuous assimilation of IMERG data

  17. Comparison between assimilated and non-assimilated experiments of the MACCii global reanalysis near surface ozone

    Science.gov (United States)

    Tsikerdekis, Athanasios; Katragou, Eleni; Zanis, Prodromos; Melas, Dimitrios; Eskes, Henk; Flemming, Johannes; Huijnen, Vincent; Inness, Antje; Kapsomenakis, Ioannis; Schultz, Martin; Stein, Olaf; Zerefos, Christos

    2014-05-01

    In this work we evaluate near surface ozone concentrations of the MACCii global reanalysis using measurements from the EMEP and AIRBASE database. The eight-year long reanalysis of atmospheric composition data covering the period 2003-2010 was constructed as part of the FP7-funded Monitoring Atmospheric Composition and Climate project by assimilating satellite data into a global model and data assimilation system (Inness et al., 2013). The study mainly focuses in the differences between the assimilated and the non-assimilated experiments and aims to identify and quantify any improvements achieved by adding data assimilation to the system. Results are analyzed in eight European sub-regions and region-specific Taylor plots illustrate the evaluation and the overall predictive skill of each experiment. The diurnal and annual cycles of near surface ozone are evaluated for both experiments. Furthermore ozone exposure indices for crop growth (AOT40), human health (SOMO35) and the number of days that 8-hour ozone averages exceeded 60ppb and 90ppb have been calculated for each station based on both observed and simulated data. Results indicate mostly improvement of the assimilated experiment with respect to the high near surface ozone concentrations, the diurnal cycle and range and the bias in comparison to the non-assimilated experiment. The limitations of the comparison between assimilated and non-assimilated experiments for near surface ozone are also discussed.

  18. Assimilation of Baba and Nyonya in Malaysia

    OpenAIRE

    Razaleigh Muhamat Kawangit

    2015-01-01

    This research set outs to explore the exact level of the social aspect of assimilation between Baba and Nyonya and their Malay counterparts in Malaysia. It was sure that assimilation in social aspect is a dilemma which Baba and Nyonya face when they interact with Malays as a dominant ethnic group. It suggests that when the process of interaction, their behavior changes in line with the identity of the Malays. This is because the majority influenced the minority in the Malaysian context. Whils...

  19. Computational methods for data evaluation and assimilation

    CERN Document Server

    Cacuci, Dan Gabriel

    2013-01-01

    Data evaluation and data combination require the use of a wide range of probability theory concepts and tools, from deductive statistics mainly concerning frequencies and sample tallies to inductive inference for assimilating non-frequency data and a priori knowledge. Computational Methods for Data Evaluation and Assimilation presents interdisciplinary methods for integrating experimental and computational information. This self-contained book shows how the methods can be applied in many scientific and engineering areas. After presenting the fundamentals underlying the evaluation of experiment

  20. Temporal Reference, Attentional Modulation, and Crossmodal Assimilation

    Directory of Open Access Journals (Sweden)

    Yingqi Wan

    2018-06-01

    Full Text Available Crossmodal assimilation effect refers to the prominent phenomenon by which ensemble mean extracted from a sequence of task-irrelevant distractor events, such as auditory intervals, assimilates/biases the perception (such as visual interval of the subsequent task-relevant target events in another sensory modality. In current experiments, using visual Ternus display, we examined the roles of temporal reference, materialized as the time information accumulated before the onset of target event, as well as the attentional modulation in crossmodal temporal interaction. Specifically, we examined how the global time interval, the mean auditory inter-intervals and the last interval in the auditory sequence assimilate and bias the subsequent percept of visual Ternus motion (element motion vs. group motion. We demonstrated that both the ensemble (geometric mean and the last interval in the auditory sequence contribute to bias the percept of visual motion. Longer mean (or last interval elicited more reports of group motion, whereas the shorter mean (or last auditory intervals gave rise to more dominant percept of element motion. Importantly, observers have shown dynamic adaptation to the temporal reference of crossmodal assimilation: when the target visual Ternus stimuli were separated by a long gap interval after the preceding sound sequence, the assimilation effect by ensemble mean was reduced. Our findings suggested that crossmodal assimilation relies on a suitable temporal reference on adaptation level, and revealed a general temporal perceptual grouping principle underlying complex audio-visual interactions in everyday dynamic situations.

  1. A simple lightning assimilation technique for improving ...

    Science.gov (United States)

    Convective rainfall is often a large source of error in retrospective modeling applications. In particular, positive rainfall biases commonly exist during summer months due to overactive convective parameterizations. In this study, lightning assimilation was applied in the Kain-Fritsch (KF) convective scheme to improve retrospective simulations using the Weather Research and Forecasting (WRF) model. The assimilation method has a straightforward approach: force KF deep convection where lightning is observed and, optionally, suppress deep convection where lightning is absent. WRF simulations were made with and without lightning assimilation over the continental United States for July 2012, July 2013, and January 2013. The simulations were evaluated against NCEP stage-IV precipitation data and MADIS near-surface meteorological observations. In general, the use of lightning assimilation considerably improves the simulation of summertime rainfall. For example, the July 2012 monthly averaged bias of 6 h accumulated rainfall is reduced from 0.54 to 0.07 mm and the spatial correlation is increased from 0.21 to 0.43 when lightning assimilation is used. Statistical measures of near-surface meteorological variables also are improved. Consistent improvements also are seen for the July 2013 case. These results suggest that this lightning assimilation technique has the potential to substantially improve simulation of warm-season rainfall in retrospective WRF applications. The

  2. Data Assimilation: Making Sense of Earth Observation

    Directory of Open Access Journals (Sweden)

    William Albert Lahoz

    2014-05-01

    Full Text Available Climate change, air quality and environmental degradation are important societal challenges for the 21st Century. These challenges require an intelligent response from society, which in turn requires access to information about the Earth System. This information comes from observations and prior knowledge, the latter typically embodied in a model describing relationships between variables of the Earth System. Data assimilation provides an objective methodology to combine observational and model information to provide an estimate of the most likely state and its uncertainty for the whole Earth System. This approach adds value to the observations – by filling in the spatio-temporal gaps in observations; and to the model – by constraining it with the observations. In this review paper we motivate data assimilation as a methodology to fill in the gaps in observational information; illustrate the data assimilation approach with examples that span a broad range of features of the Earth System (atmosphere, including chemistry; ocean; land surface; and discuss the outlook for data assimilation, including the novel application of data assimilation ideas to observational information obtained using Citizen Science. Ultimately, a strong motivation of data assimilation is the many benefits it provides to users. These include: providing the initial state for weather and air quality forecasts; providing analyses and reanalyses for studying the Earth System; evaluating observations, instruments and models; assessing the relative value of elements of the Global Observing System (GOS; and assessing the added value of future additions to the GOS.

  3. Assimilate partitioning in avocado, Persea americana

    Energy Technology Data Exchange (ETDEWEB)

    Finazzo, S.; Davenport, T.L.

    1986-04-01

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13..mu..Ci of /sup 14/CO/sub 2/. The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of /sup 14/C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most /sup 14/C. Source leaves for single non-abscising fruitlets retained 3X more /sup 14/C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern.

  4. Assimilate partitioning in avocado, Persea americana

    International Nuclear Information System (INIS)

    Finazzo, S.; Davenport, T.L.

    1986-01-01

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13μCi of 14 CO 2 . The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of 14 C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most 14 C. Source leaves for single non-abscising fruitlets retained 3X more 14 C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern

  5. Data assimilation in the decision support system RODOS

    International Nuclear Information System (INIS)

    Rojas-Palma, C.; Madsen, H.; Gering, F.; Puch, R.; Turcanu, C.; Astrup, P.; Mueller, H.; Richter, K.; Zheleznyak, M.; Treebushny, D.; Kolomeev, M.; Kamaev, D.; Wynn, H.

    2003-01-01

    Model predictions for a rapid assessment and prognosis of possible radiological consequences after an accidental release of radionuclides play an important role in nuclear emergency management. Radiological observations, e.g. dose rate measurements, can be used to improve such model predictions. The process of combining model predictions and observations, usually referred to as data assimilation, is described in this article within the framework of the real time on-line decision support system (RODOS) for off-site nuclear emergency management in Europe. Data assimilation capabilities, based on Kalman filters,are under development for several modules of the RODOS system, including the atmospheric dispersion, deposition, food chain and hydrological models. The use of such a generic data assimilation methodology enables the propagation of uncertainties throughout the various modules of the system. This would in turn provide decision makers with uncertainty estimates taking into account both model and observation errors. This paper describes the methodology employed as well as results of some preliminary studies based on simulated data. (author)

  6. Assimilation of total lightning data using the three-dimensional variational method at convection-allowing resolution

    Science.gov (United States)

    Zhang, Rong; Zhang, Yijun; Xu, Liangtao; Zheng, Dong; Yao, Wen

    2017-08-01

    A large number of observational analyses have shown that lightning data can be used to indicate areas of deep convection. It is important to assimilate observed lightning data into numerical models, so that more small-scale information can be incorporated to improve the quality of the initial condition and the subsequent forecasts. In this study, the empirical relationship between flash rate, water vapor mixing ratio, and graupel mixing ratio was used to adjust the model relative humidity, which was then assimilated by using the three-dimensional variational data assimilation system of the Weather Research and Forecasting model in cycling mode at 10-min intervals. To find the appropriate assimilation time-window length that yielded significant improvement in both the initial conditions and subsequent forecasts, four experiments with different assimilation time-window lengths were conducted for a squall line case that occurred on 10 July 2007 in North China. It was found that 60 min was the appropriate assimilation time-window length for this case, and longer assimilation window length was unnecessary since no further improvement was present. Forecasts of 1-h accumulated precipitation during the assimilation period and the subsequent 3-h accumulated precipitation were significantly improved compared with the control experiment without lightning data assimilation. The simulated reflectivity was optimal after 30 min of the forecast, it remained optimal during the following 42 min, and the positive effect from lightning data assimilation began to diminish after 72 min of the forecast. Overall, the improvement from lightning data assimilation can be maintained for about 3 h.

  7. Transportation assimilation revisited: New evidence from repeated cross-sectional survey data

    Science.gov (United States)

    2018-01-01

    Background Based on single cross-sectional data, prior research finds evidence of “transportation assimilation” among U.S. immigrants: the length of stay in the U.S. is negatively correlated with public transit use. This paper revisits this question by using repeated cross-sectional data, and examines the trend of transportation assimilation over time. Methods and results Using 1980, 1990, 2000 1% census and 2010 (1%) American Community Survey, I examine the relationship between the length of stay in the U.S. and public transit ridership among immigrants. I first run regressions separately in four data sets: I regress public transit ridership on the length of stay, controlling for other individual and geographic variables. I then compare the magnitudes of the relationship in four regressions. To study how the rate of transportation assimilation changes over time, I pool the data set and regress public transit ridership on the length of stay and its interactions with year dummies to compare the coefficients across surveys. Results confirm the conclusion of transportation assimilation: as the length of stay in the U.S. increases, an immigrant’s public transit use decreases. However, the repeated cross-section analysis suggests the assimilation rate has been decreasing in the past few decades. Conclusions This paper finds evidence of transportation assimilation: immigrants become less likely to ride public transit as the length of stay in the U.S. increases. The assimilation rate, however, has been decreasing over time. This paper finds that the rate of public transit ridership among new immigrants upon arrival, the geographic distribution of immigrants, and the changing demographics of the U.S. immigrants play roles in affecting the trend of transportation assimilation. PMID:29668676

  8. Application of Bred Vectors To Data Assimilation

    Science.gov (United States)

    Corazza, M.; Kalnay, E.; Patil, Dj

    We introduced a statistic, the BV-dimension, to measure the effective local finite-time dimensionality of the atmosphere. We show that this dimension is often quite low, and suggest that this finding has important implications for data assimilation and the accuracy of weather forecasting (Patil et al, 2001). The original database for this study was the forecasts of the NCEP global ensemble forecasting system. The initial differences between the control forecast and the per- turbed forecasts are called bred vectors. The control and perturbed initial conditions valid at time t=n(t are evolved using the forecast model until time t=(n+1) (t. The differences between the perturbed and the control forecasts are scaled down to their initial amplitude, and constitute the bred vectors valid at (n+1) (t. Their growth rate is typically about 1.5/day. The bred vectors are similar by construction to leading Lya- punov vectors except that they have small but finite amplitude, and they are valid at finite times. The original NCEP ensemble data set has 5 independent bred vectors. We define a local bred vector at each grid point by choosing the 5 by 5 grid points centered at the grid point (a region of about 1100km by 1100km), and using the north-south and east- west velocity components at 500mb pressure level to form a 50 dimensional column vector. Since we have k=5 global bred vectors, we also have k local bred vectors at each grid point. We estimate the effective dimensionality of the subspace spanned by the local bred vectors by performing a singular value decomposition (EOF analysis). The k local bred vector columns form a 50xk matrix M. The singular values s(i) of M measure the extent to which the k column unit vectors making up the matrix M point in the direction of v(i). We define the bred vector dimension as BVDIM={Sum[s(i)]}^2/{Sum[s(i)]^2} For example, if 4 out of the 5 vectors lie along v, and one lies along v, the BV- dimension would be BVDIM[sqrt(4), 1, 0

  9. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  10. Reconfiguration of distribution nets

    International Nuclear Information System (INIS)

    Latorre Bayona, Gerardo; Angarita Marquez, Jorge Luis

    2000-01-01

    Starting of the location of the reconfiguration problem inside the context of the operation of distribution nets, of the quality indicators definition and of the presentation of the alternatives more used for reduction of technical losses, they are related diverse reconfiguration methodologies proposed in the technical literature, pointing out their three principals limitations; also are presents the results of lost obtained starting from simulation works carried out in distribution circuits of the ESSA ESP, which permitting to postulate the reconfiguration of nets like an excellent alternative to reduce technical losses

  11. NET system integration

    International Nuclear Information System (INIS)

    Farfaletti-Casali, F.; Mitchell, N.; Salpietro, E.; Buzzi, U.; Gritzmann, P.

    1985-01-01

    The NET system integration procedure is the process by which the requirements of the various Tokamak machine design areas are brought together to form a compatible machine layout. Each design area produces requirements which generally allow components to be built at minimum cost and operate with minimum technical risk, and the final machine assembly should be achieved with minimum departure from these optimum designs. This is carried out in NET by allowing flexibility in the maintenance and access methods to the machine internal components which must be regularly replaced by remote handling, in segmentation of these internal components and in the number of toroidal field coils

  12. Variational data assimilation schemes for transport and transformation models of atmospheric chemistry

    Science.gov (United States)

    Penenko, Alexey; Penenko, Vladimir; Tsvetova, Elena; Antokhin, Pavel

    2016-04-01

    The work is devoted to data assimilation algorithm for atmospheric chemistry transport and transformation models. In the work a control function is introduced into the model source term (emission rate) to provide flexibility to adjust to data. This function is evaluated as the constrained minimum of the target functional combining a control function norm with a norm of the misfit between measured data and its model-simulated analog. Transport and transformation processes model is acting as a constraint. The constrained minimization problem is solved with Euler-Lagrange variational principle [1] which allows reducing it to a system of direct, adjoint and control function estimate relations. This provides a physically-plausible structure of the resulting analysis without model error covariance matrices that are sought within conventional approaches to data assimilation. High dimensionality of the atmospheric chemistry models and a real-time mode of operation demand for computational efficiency of the data assimilation algorithms. Computational issues with complicated models can be solved by using a splitting technique. Within this approach a complex model is split to a set of relatively independent simpler models equipped with a coupling procedure. In a fine-grained approach data assimilation is carried out quasi-independently on the separate splitting stages with shared measurement data [2]. In integrated schemes data assimilation is carried out with respect to the split model as a whole. We compare the two approaches both theoretically and numerically. Data assimilation on the transport stage is carried out with a direct algorithm without iterations. Different algorithms to assimilate data on nonlinear transformation stage are compared. In the work we compare data assimilation results for both artificial and real measurement data. With these data we study the impact of transformation processes and data assimilation to the performance of the modeling system [3]. The

  13. Coupled assimilation for an intermediated coupled ENSO prediction model

    Science.gov (United States)

    Zheng, Fei; Zhu, Jiang

    2010-10-01

    The value of coupled assimilation is discussed using an intermediate coupled model in which the wind stress is the only atmospheric state which is slavery to model sea surface temperature (SST). In the coupled assimilation analysis, based on the coupled wind-ocean state covariance calculated from the coupled state ensemble, the ocean state is adjusted by assimilating wind data using the ensemble Kalman filter. As revealed by a series of assimilation experiments using simulated observations, the coupled assimilation of wind observations yields better results than the assimilation of SST observations. Specifically, the coupled assimilation of wind observations can help to improve the accuracy of the surface and subsurface currents because the correlation between the wind and ocean currents is stronger than that between SST and ocean currents in the equatorial Pacific. Thus, the coupled assimilation of wind data can decrease the initial condition errors in the surface/subsurface currents that can significantly contribute to SST forecast errors. The value of the coupled assimilation of wind observations is further demonstrated by comparing the prediction skills of three 12-year (1997-2008) hindcast experiments initialized by the ocean-only assimilation scheme that assimilates SST observations, the coupled assimilation scheme that assimilates wind observations, and a nudging scheme that nudges the observed wind stress data, respectively. The prediction skills of two assimilation schemes are significantly better than those of the nudging scheme. The prediction skills of assimilating wind observations are better than assimilating SST observations. Assimilating wind observations for the 2007/2008 La Niña event triggers better predictions, while assimilating SST observations fails to provide an early warning for that event.

  14. Coloured Petri Nets

    CERN Document Server

    Jensen, Kurt

    2009-01-01

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. This book introduces the constructs of the CPN modelling language and presents the related analysis methods. It provides a comprehensive road map for the practical use of CPN.

  15. Safety nets or straitjackets?

    DEFF Research Database (Denmark)

    Ilsøe, Anna

    2012-01-01

    Does regulation of working hours at national and sector level impose straitjackets, or offer safety nets to employees seeking working time flexibility? This article compares legislation and collective agreements in the metal industries of Denmark, Germany and the USA. The industry has historically...

  16. Neuronal nets in robotics

    International Nuclear Information System (INIS)

    Jimenez Sanchez, Raul

    1999-01-01

    The paper gives a generic idea of the solutions that the neuronal nets contribute to the robotics. The advantages and the inconveniences are exposed that have regarding the conventional techniques. It also describe the more excellent applications as the pursuit of trajectories, the positioning based on images, the force control or of the mobile robots management, among others

  17. Net4Care platform

    DEFF Research Database (Denmark)

    2012-01-01

    , that in turn enables general practitioners and clinical staff to view observations. Use the menus above to explore the site's information resources. To get started, follow the short Hello, World! tutorial. The Net4Care project is funded by The Central Denmark Region and EU via Caretech Innovation....

  18. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars Michael

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism an...

  19. Game Theory .net.

    Science.gov (United States)

    Shor, Mikhael

    2003-01-01

    States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  20. BacillusRegNet

    DEFF Research Database (Denmark)

    Misirli, Goksel; Hallinan, Jennifer; Röttger, Richard

    2014-01-01

    As high-throughput technologies become cheaper and easier to use, raw sequence data and corresponding annotations for many organisms are becoming available. However, sequence data alone is not sufficient to explain the biological behaviour of organisms, which arises largely from complex molecular...... the associated BacillusRegNet website (http://bacillus.ncl.ac.uk)....

  1. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian

    1999-01-01

    of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  2. Model Uncertainty Quantification Methods In Data Assimilation

    Science.gov (United States)

    Pathiraja, S. D.; Marshall, L. A.; Sharma, A.; Moradkhani, H.

    2017-12-01

    Data Assimilation involves utilising observations to improve model predictions in a seamless and statistically optimal fashion. Its applications are wide-ranging; from improving weather forecasts to tracking targets such as in the Apollo 11 mission. The use of Data Assimilation methods in high dimensional complex geophysical systems is an active area of research, where there exists many opportunities to enhance existing methodologies. One of the central challenges is in model uncertainty quantification; the outcome of any Data Assimilation study is strongly dependent on the uncertainties assigned to both observations and models. I focus on developing improved model uncertainty quantification methods that are applicable to challenging real world scenarios. These include developing methods for cases where the system states are only partially observed, where there is little prior knowledge of the model errors, and where the model error statistics are likely to be highly non-Gaussian.

  3. Data assimilation the ensemble Kalman filter

    CERN Document Server

    Evensen, Geir

    2007-01-01

    Data Assimilation comprehensively covers data assimilation and inverse methods, including both traditional state estimation and parameter estimation. This text and reference focuses on various popular data assimilation methods, such as weak and strong constraint variational methods and ensemble filters and smoothers. It is demonstrated how the different methods can be derived from a common theoretical basis, as well as how they differ and/or are related to each other, and which properties characterize them, using several examples. Rather than emphasize a particular discipline such as oceanography or meteorology, it presents the mathematical framework and derivations in a way which is common for any discipline where dynamics is merged with measurements. The mathematics level is modest, although it requires knowledge of basic spatial statistics, Bayesian statistics, and calculus of variations. Readers will also appreciate the introduction to the mathematical methods used and detailed derivations, which should b...

  4. Characteristics and assimilation of Chinese immigrants in the U.S. labour market.

    Science.gov (United States)

    Chen, S J

    1998-01-01

    "Using U.S. Public Use Samples, this article examines differences in the quality and assimilation rate of different Chinese immigrant groups (immigrants from Hong Kong, Taiwan and Mainland China) in the U.S. labour market. The descriptive statistics show great differences among Chinese immigrants from the three areas in their ages, wage rates, years of schooling and industrial and occupational distributions. This article also finds that the three Chinese immigrant groups have much more dispersed wage distributions than U.S.-born workers have. The three Chinese immigrant groups also experienced substantial assimilation into the U.S. labour market during the 1980s." (EXCERPT)

  5. Assimilation, partitioning, and nonstructural carbohydrates in sweet compared with grain sorghum

    International Nuclear Information System (INIS)

    Vietor, D.M.; Miller, F.R.

    1990-01-01

    Nonstructural carbohydrate concentrations in stems are greater for sweet than grain sorghums [Sorghum bicolor (L.) Moench]. Knowledge of plant characteristics associated with high nonstructural carbohydrates in sweet sorghum will air efforts to increase nonstructural carbohydrates in grain sorghum stems. This study tested the hypothesis that variation of CO 2 assimilation rate, leaf area, branching at upper nodes, and partitioning of 14 C-labeled assimilate to main stems are associated with variation of stem nonstructural carbohydrates. A sweet (Atlas X Rio) and a grain (ATx623 X RTx5388) hybrid, stages near and after physiological maturity, and defoliation and gibberellic acid (GA 3 ) treatments provided sources of variation for study. Concentrations of nonstructural carbohydrates in lower and upper stems of the sweet hybrid were 1.4 and 2.7 times higher, respectively, than for the grain hybrid, after physiological maturity. Variation in branching, including 14 C-assimilate partitioning to branches, was not consistently associated with hybrid differences in stem nonstructural carbohydrates. Increased recovery (twofold) of 14 C-assimilate in roots and labeled leaves corresponded with lower percentages of 14 C-assimilate and lower concentrations of nonstructural carbohydrates in stems of the grain hybrid. Leaf areas and leaf CO 2 exchange rate were twice as great for the sweet hybrid. Although defoliation of the sweet hybrid minimized leaf area differences between hybrids, the sweet hybrid accumulated twice as much nonstructural carbohydrates in branches after physiological maturity. Greater potentials for CO 2 assimilation and for 14 C-assimilate accumulation in mature stem tissue were associated with higher levels of stem nonstructural carbohydrates in the sweet compared with the grain hybrid

  6. Scalable and balanced dynamic hybrid data assimilation

    Science.gov (United States)

    Kauranne, Tuomo; Amour, Idrissa; Gunia, Martin; Kallio, Kari; Lepistö, Ahti; Koponen, Sampsa

    2017-04-01

    Scalability of complex weather forecasting suites is dependent on the technical tools available for implementing highly parallel computational kernels, but to an equally large extent also on the dependence patterns between various components of the suite, such as observation processing, data assimilation and the forecast model. Scalability is a particular challenge for 4D variational assimilation methods that necessarily couple the forecast model into the assimilation process and subject this combination to an inherently serial quasi-Newton minimization process. Ensemble based assimilation methods are naturally more parallel, but large models force ensemble sizes to be small and that results in poor assimilation accuracy, somewhat akin to shooting with a shotgun in a million-dimensional space. The Variational Ensemble Kalman Filter (VEnKF) is an ensemble method that can attain the accuracy of 4D variational data assimilation with a small ensemble size. It achieves this by processing a Gaussian approximation of the current error covariance distribution, instead of a set of ensemble members, analogously to the Extended Kalman Filter EKF. Ensemble members are re-sampled every time a new set of observations is processed from a new approximation of that Gaussian distribution which makes VEnKF a dynamic assimilation method. After this a smoothing step is applied that turns VEnKF into a dynamic Variational Ensemble Kalman Smoother VEnKS. In this smoothing step, the same process is iterated with frequent re-sampling of the ensemble but now using past iterations as surrogate observations until the end result is a smooth and balanced model trajectory. In principle, VEnKF could suffer from similar scalability issues as 4D-Var. However, this can be avoided by isolating the forecast model completely from the minimization process by implementing the latter as a wrapper code whose only link to the model is calling for many parallel and totally independent model runs, all of them

  7. Net ecosystem CO2 exchange over a larch forest in Hokkaido, Japan

    International Nuclear Information System (INIS)

    Huimin Wang; Saigusa, Nobuko; Yamamoto, Susumu; Kondo, Hiroaki; Hirano, Takashi; Toriyama, Atsushi; Fujinuma, Yasumi

    2004-01-01

    Larch forests are distributed extensively in the east Eurasian continent and are expected to play a significant role in the terrestrial ecosystem carbon cycling process. In view of the fact that studies on carbon exchange for this important biome have been very limited, we have initiated a long-term flux observation in a larch forest ecosystem in Hokkaido in northern Japan since 2000. The net ecosystem CO 2 exchange (NEE) showed large seasonal and diurnal variation. Generally, the larch forest ecosystem released CO 2 in nighttime and assimilated CO 2 in daytime during the growing season from May to October. The ecosystem started to become a net carbon sink in May, reaching a maximum carbon uptake as high as 186 g C m -2 month -1 in June. With the yellowing, senescing and leaf fall, the ecosystem turned into a carbon source in November. During the non-growing season, the larch forest ecosystem became a net source of CO 2 , releasing an average of 16.7 g C m -2 month -1 . Overall, the ecosystem sequestered 141-240 g C m -2 yr -1 in 2001. The NEE was significantly influenced by environmental factors. Respiration of the ecosystem, for example, was exponentially dependent on air temperature, while photosynthesis was related to the incident PAR in a manner consistent with the Michaelis-Menten model. Although the vapor pressure deficit (VPD) was scarcely higher than 15 hPa, the CO 2 uptake rate was also depressed when VPD surpassed 10 hPa (Author)

  8. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris

    2014-01-01

    -accompanying Master courses, placements of internships, and PhD scholarship projects. A new scholarship project, “SHINE”, was launched in autumn 2013 in the frame work of the Marie Curie program of the European Union (Initial Training Network, ITN). 13 PhD-scholarships on solar district heating, solar heat......SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference...... for industrial processes, as well as sorption stores and materials started in December 2013. Additionally, the project comprises a training program with five PhD courses and several workshops on solar thermal engineering that will be open also for other PhD students working in the field. The research projects...

  9. [Simulation of water and carbon fluxes in harvard forest area based on data assimilation method].

    Science.gov (United States)

    Zhang, Ting-Long; Sun, Rui; Zhang, Rong-Hua; Zhang, Lei

    2013-10-01

    Model simulation and in situ observation are the two most important means in studying the water and carbon cycles of terrestrial ecosystems, but have their own advantages and shortcomings. To combine these two means would help to reflect the dynamic changes of ecosystem water and carbon fluxes more accurately. Data assimilation provides an effective way to integrate the model simulation and in situ observation. Based on the observation data from the Harvard Forest Environmental Monitoring Site (EMS), and by using ensemble Kalman Filter algorithm, this paper assimilated the field measured LAI and remote sensing LAI into the Biome-BGC model to simulate the water and carbon fluxes in Harvard forest area. As compared with the original model simulated without data assimilation, the improved Biome-BGC model with the assimilation of the field measured LAI in 1998, 1999, and 2006 increased the coefficient of determination R2 between model simulation and flux observation for the net ecosystem exchange (NEE) and evapotranspiration by 8.4% and 10.6%, decreased the sum of absolute error (SAE) and root mean square error (RMSE) of NEE by 17.7% and 21.2%, and decreased the SAE and RMSE of the evapotranspiration by 26. 8% and 28.3%, respectively. After assimilated the MODIS LAI products of 2000-2004 into the improved Biome-BGC model, the R2 between simulated and observed results of NEE and evapotranspiration was increased by 7.8% and 4.7%, the SAE and RMSE of NEE were decreased by 21.9% and 26.3%, and the SAE and RMSE of evapotranspiration were decreased by 24.5% and 25.5%, respectively. It was suggested that the simulation accuracy of ecosystem water and carbon fluxes could be effectively improved if the field measured LAI or remote sensing LAI was integrated into the model.

  10. Differentiation between Trichophyton mentagrophytes and T. rubrum by sorbitol assimilation.

    OpenAIRE

    Rezusta, A; Rubio, M C; Alejandre, M C

    1991-01-01

    Trichophyton rubrum was easily differentiated from T. mentagrophytes by its ability to assimilate sorbitol with an API 20C AUX strip. One hundred percent of 36 T. rubrum strains and none of 147 T. mentagrophytes strains assimilated sorbitol.

  11. Assimilation of Doppler weather radar observations in a mesoscale ...

    Indian Academy of Sciences (India)

    Research (PSU–NCAR) mesoscale model (MM5) version 3.5.6. The variational data assimilation ... investigation of the direct assimilation of radar reflectivity data in 3DVAR system. The present ...... Results presented in this paper are based on.

  12. Turkey's net energy consumption

    International Nuclear Information System (INIS)

    Soezen, Adnan; Arcaklioglu, Erol; Oezkaymak, Mehmet

    2005-01-01

    The main goal of this study is to develop the equations for forecasting net energy consumption (NEC) using an artificial neural-network (ANN) technique in order to determine the future level of energy consumption in Turkey. In this study, two different models were used in order to train the neural network. In one of them, population, gross generation, installed capacity and years are used in the input layer of the network (Model 1). Other energy sources are used in input layer of network (Model 2). The net energy consumption is in the output layer for two models. Data from 1975 to 2003 are used for the training. Three years (1981, 1994 and 2003) are used only as test data to confirm this method. The statistical coefficients of multiple determinations (R 2 -value) for training data are equal to 0.99944 and 0.99913 for Models 1 and 2, respectively. Similarly, R 2 values for testing data are equal to 0.997386 and 0.999558 for Models 1 and 2, respectively. According to the results, the net energy consumption using the ANN technique has been predicted with acceptable accuracy. Apart from reducing the whole time required, with the ANN approach, it is possible to find solutions that make energy applications more viable and thus more attractive to potential users. It is also expected that this study will be helpful in developing highly applicable energy policies

  13. Data assimilation of CALIPSO aerosol observations

    Directory of Open Access Journals (Sweden)

    T. T. Sekiyama

    2010-01-01

    Full Text Available We have developed an advanced data assimilation system for a global aerosol model with a four-dimensional ensemble Kalman filter in which the Level 1B data from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO were successfully assimilated for the first time, to the best of the authors' knowledge. A one-month data assimilation cycle experiment for dust, sulfate, and sea-salt aerosols was performed in May 2007. The results were validated via two independent observations: 1 the ground-based lidar network in East Asia, managed by the National Institute for Environmental Studies of Japan, and 2 weather reports of aeolian dust events in Japan. Detailed four-dimensional structures of aerosol outflows from source regions over oceans and continents for various particle types and sizes were well reproduced. The intensity of dust emission at each grid point was also corrected by this data assimilation system. These results are valuable for the comprehensive analysis of aerosol behavior as well as aerosol forecasting.

  14. Development of a data assimilation algorithm

    DEFF Research Database (Denmark)

    Thomsen, Per Grove; Zlatev, Zahari

    2008-01-01

    It is important to incorporate all available observations when large-scale mathematical models arising in different fields of science and engineering are used to study various physical and chemical processes. Variational data assimilation techniques can be used in the attempts to utilize efficien......It is important to incorporate all available observations when large-scale mathematical models arising in different fields of science and engineering are used to study various physical and chemical processes. Variational data assimilation techniques can be used in the attempts to utilize...... assimilation technique is applied. Therefore, it is important to study the interplay between the three components of the variational data assimilation techniques as well as to apply powerful parallel computers in the computations. Some results obtained in the search for a good combination of numerical methods...... computers, Mathematics and Computers in Simulation, 65 (2004) 557–577, Z. Zlatev, Computer Treatment of Large Air Pollution Models, Kluwer Academic Publishers, Dordrecht, Boston, London, 1995]. The ideas are rather general and can easily be applied in connection with other mathematical models....

  15. Nitrogen assimilation in soybean nodules, 1

    International Nuclear Information System (INIS)

    Ohyama, Takuji; Kumazawa, Kikuo

    1980-01-01

    In order to elucidate the pathways to assimilate the ammonia produced by N 2 -fixation in soybean nodules, 15 N-labeled compounds were administered to intact nodules or nodule slices pretreated with various inhibitors of nitrogen assimilation. After exposure to 15 N 2 , 15 N-incorporation into various nitrogenous compounds was investigated in attached nodules injected with methionine sulfoximine (MSX) or azaserine (AS). MSX treatment increased the 15 N content of ammonia more than 6 times, however, depressed 15 N content of most of amides and amino acids. AS treatment enhanced 15 N content of amido-N of glutamine as well as ammonia, but decreased amino-N of glutamine and most of amino acids. Experiments with nodule slices pretreated with MSX or AS solution and then fed with 15 N-labeled ammonia or amido- 15 N of glutamine showed the same trends. Aminooxyacetate inhibited nitrogen flow from glutamic acid to other amino acids. These results strongly indicate that the ammonia produced by N 2 -fixation is assimilated by GS/GOGAT system to glutamic acid and then transaminated to various amino acids in situ. 15 N-incorporation patterns in nodule slices fed with 15 N-labeled ammonia, hydroxylamine, nitrite were similar, but nitrate seemed to be reduced in a definite compartment and assimilated similarly as in intact nodules fed with 15 N 2 (author)

  16. Data assimilation for air quality models

    DEFF Research Database (Denmark)

    Silver, Jeremy David

    2014-01-01

    -dimensional optimal interpolation procedure (OI), an Ensemble Kalman Filter (EnKF), and a three-dimensional variational scheme (3D-var). The three assimilation procedures are described and tested. A multi-faceted approach is taken for the verification, using independent measurements from surface air-quality...

  17. Data ingestion and assimilation in ionospheric models

    Czech Academy of Sciences Publication Activity Database

    Burešová, Dalia; Nava, B.; Galkin, I.; Angling, M.; Stankov, S. M.; Coisson, P.

    2009-01-01

    Roč. 52, 3/4 (2009), s. 235-253 ISSN 1593-5213 R&D Projects: GA ČR GA205/08/1356; GA MŠk OC 091 Institutional research plan: CEZ:AV0Z30420517 Keywords : ionosphere * models * data assimilation * data ingestion Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.548, year: 2009

  18. SynechoNET: integrated protein-protein interaction database of a model cyanobacterium Synechocystis sp. PCC 6803

    OpenAIRE

    Kim, Woo-Yeon; Kang, Sungsoo; Kim, Byoung-Chul; Oh, Jeehyun; Cho, Seongwoong; Bhak, Jong; Choi, Jong-Soon

    2008-01-01

    Background Cyanobacteria are model organisms for studying photosynthesis, carbon and nitrogen assimilation, evolution of plant plastids, and adaptability to environmental stresses. Despite many studies on cyanobacteria, there is no web-based database of their regulatory and signaling protein-protein interaction networks to date. Description We report a database and website SynechoNET that provides predicted protein-protein interactions. SynechoNET shows cyanobacterial domain-domain interactio...

  19. On the sseparation of net ecosystem exchange into assimilation and ecosystemrespiration: review and improved algorithm

    Czech Academy of Sciences Publication Activity Database

    Reichstein, M.; Falge, E.; Baldocchi, D.; Papale, D.; Aubinet, M.; Berbigier, P.; Bernhofer, Ch.; Buchmann, N.; Gilmanov, T.; Granier, A.; Grunwald, T.; Havránková, Kateřina; Ilvesniemi, H.; Janouš, Dalibor; Knohl, A.; Laurila, T.; Lohila, A.; Loustau, D.; Matteucci, G.; Meyers, T.; Miglietta, F.; Ourcival, J.M.; Pumpanen, J.; Rambal, S.; Rotenberg, E.; Sanz, M.; Tenhunen, J.; Seufert, G.; Vaccari, F.; Vesala, T.; Yakir, D.; Valentini, R.

    2005-01-01

    Roč. 11, č. 9 (2005), s. 1424-1439 ISSN 1354-1013 Institutional research plan: CEZ:AV0Z60870520 Keywords : CO2 fluxes * ecosystem carbon budget * stable isotopes Subject RIV: GK - Forestry Impact factor: 4.075, year: 2005

  20. Empowering Geoscience with Improved Data Assimilation Using the Data Assimilation Research Testbed "Manhattan" Release.

    Science.gov (United States)

    Raeder, K.; Hoar, T. J.; Anderson, J. L.; Collins, N.; Hendricks, J.; Kershaw, H.; Ha, S.; Snyder, C.; Skamarock, W. C.; Mizzi, A. P.; Liu, H.; Liu, J.; Pedatella, N. M.; Karspeck, A. R.; Karol, S. I.; Bitz, C. M.; Zhang, Y.

    2017-12-01

    The capabilities of the Data Assimilation Research Testbed (DART) at NCAR have been significantly expanded with the recent "Manhattan" release. DART is an ensemble Kalman filter based suite of tools, which enables researchers to use data assimilation (DA) without first becoming DA experts. Highlights: significant improvement in efficient ensemble DA for very large models on thousands of processors, direct read and write of model state files in parallel, more control of the DA output for finer-grained analysis, new model interfaces which are useful to a variety of geophysical researchers, new observation forward operators and the ability to use precomputed forward operators from the forecast model. The new model interfaces and example applications include the following: MPAS-A; Model for Prediction Across Scales - Atmosphere is a global, nonhydrostatic, variable-resolution mesh atmospheric model, which facilitates multi-scale analysis and forecasting. The absence of distinct subdomains eliminates problems associated with subdomain boundaries. It demonstrates the ability to consistently produce higher-quality analyses than coarse, uniform meshes do. WRF-Chem; Weather Research and Forecasting + (MOZART) Chemistry model assimilates observations from FRAPPÉ (Front Range Air Pollution and Photochemistry Experiment). WACCM-X; Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension assimilates observations of electron density to investigate sudden stratospheric warming. CESM (weakly) coupled assimilation; NCAR's Community Earth System Model is used for assimilation of atmospheric and oceanic observations into their respective components using coupled atmosphere+land+ocean+sea+ice forecasts. CESM2.0; Assimilation in the atmospheric component (CAM, WACCM) of the newly released version is supported. This version contains new and extensively updated components and software environment. CICE; Los Alamos sea ice model (in CESM) is used to assimilate

  1. Net one, net two: the primary care network income statement.

    Science.gov (United States)

    Halley, M D; Little, A W

    1999-10-01

    Although hospital-owned primary care practices have been unprofitable for most hospitals, some hospitals are achieving competitive advantage and sustainable practice operations. A key to the success of some has been a net income reporting tool that separates practice operating expenses from the costs of creating and operating a network of practices to help healthcare organization managers, physicians, and staff to identify opportunities to improve the network's financial performance. This "Net One, Net Two" reporting allows operations leadership to be held accountable for Net One expenses and strategic leadership to be held accountable for Net Two expenses.

  2. Proof Nets for Lambek Calculus

    NARCIS (Netherlands)

    Roorda, Dirk

    1992-01-01

    The proof nets of linear logic are adapted to the non-commutative Lambek calculus. A different criterion for soundness of proof nets is given, which gives rise to new algorithms for proof search. The order sensitiveness of the Lambek calculus is reflected by the planarity condition on proof nets;

  3. Net metering: zero electricity bill

    International Nuclear Information System (INIS)

    Mangi, A.; Khan, Z.

    2011-01-01

    Worldwide move towards renewable energy sources, environmental concerns and decentralization of the power sector have made net metering an attractive option for power generation at small scale. This paper discusses the net metering, economical issues of renewable sources in Pakistan, technical aspects, installation suitability according to varying terrain, existing utility rules and formulation of legislation for net metering making it economically attractive. (author)

  4. The Net Advance of Physics

    Science.gov (United States)

    THE NET ADVANCE OF PHYSICS Review Articles and Tutorials in an Encyclopædic Format Established 1995 [Link to MIT] Computer support for The Net Advance of Physics is furnished by The Massachusetts Newest Additions SPECIAL FEATURES: Net Advance RETRO: Nineteenth Century Physics History of Science

  5. 78 FR 72393 - Net Investment Income Tax

    Science.gov (United States)

    2013-12-02

    ... of Article 23 (Relief from Double Taxation) of the 2006 United States Model Income Tax Convention... taxation of ANSTs at the lowest individual tax rate. Furthermore, section 646 treats all distributions, to... of Net Investment Income. The regulations affect individuals, estates, and trusts whose incomes meet...

  6. Horizontal ichthyoplankton tow-net system with unobstructed net opening

    Science.gov (United States)

    Nester, Robert T.

    1987-01-01

    The larval fish sampler described here consists of a modified bridle, frame, and net system with an obstruction-free net opening and is small enough for use on boats 10 m or less in length. The tow net features a square net frame attached to a 0.5-m-diameter cylinder-on-cone plankton net with a bridle designed to eliminate all obstructions forward of the net opening, significantly reducing currents and vibrations in the water directly preceding the net. This system was effective in collecting larvae representing more than 25 species of fish at sampling depths ranging from surface to 10 m and could easily be used at greater depths.

  7. Dioxin and phthalate uptake and assimilation by the green mussel Perna viridis

    International Nuclear Information System (INIS)

    Wang, Wen-Xiong; Zhang, Qiong

    2013-01-01

    In this study, the aqueous uptake and dietary assimilation (trophic transfer) of two endocrine disrupting compounds (dioxin and phathalic acid) in the green mussel Perna viridis were quantified. During short-term exposure period, dioxin rapidly sorbed onto phytoplankton and its accumulation was much higher than that of phthalate. The uptake of these two compounds by the mussels increased with increasing temperature and salinity (for dioxin only). The dietary assimilation of the two contaminants was rather modest (10–64% for dioxin and 20–47% for phthalate), and was greatly dependent on the food species and concentration. Interestingly, dietary assimilation increased with increasing diatom food concentration. Gut passage time was partially responsible for the variable dietary assimilation. Given the high dissolved uptake rate and the modest dietary assimilation, aqueous exposure was predicted to be the dominant bioaccumulation source for both dioxin and phthalate in the green mussels under most conditions. -- Capsule: Aqueous uptake was the predominant pathway for dioxin and phthalate accumulation in marine green mussels

  8. Effect of gamma radiation on photosynthetic metabolism of Chlorella pyrenoidosa studied by 14CO2 assimilation

    International Nuclear Information System (INIS)

    Martin Moreno, C.; Fernandez Gonzalez, J.

    1983-01-01

    The effect of five dose of gamma radiation (10, 100, 500, 1000 and 5000 Gy) on photosynthetic activity and metabolism of the primary products of photosynthesis has been studied, on Chlorella pyrenoidoBa cultures, by 14 C O 2 assimilation. The photosynthetic assimilation rate is remarkably depressed after irradiation at 500, 1000 and 5000 Gy dose, which also produce a significant change in radioactivity distribution pattern of primary compounds from photosynthesis. No significant effects have been observed on photosynthetic metabolism after irradiation at 10 and 100 Gy. (Author) 19 refs

  9. Master Robotic Net

    Directory of Open Access Journals (Sweden)

    Vladimir Lipunov

    2010-01-01

    Full Text Available The main goal of the MASTER-Net project is to produce a unique fast sky survey with all sky observed over a single night down to a limiting magnitude of 19-20. Such a survey will make it possible to address a number of fundamental problems: search for dark energy via the discovery and photometry of supernovae (including SNIa, search for exoplanets, microlensing effects, discovery of minor bodies in the Solar System, and space-junk monitoring. All MASTER telescopes can be guided by alerts, and we plan to observe prompt optical emission from gamma-ray bursts synchronously in several filters and in several polarization planes.

  10. Does assimilate supply limit expansion in wheat grown in the field under low phosphorus availability

    NARCIS (Netherlands)

    Rodriguez, D.; Andrade, F.H.; Goudriaan, J.

    2000-01-01

    Under conditions of phosphorus deficiency, reductions in plant leaf area have been attributed to both direct effects of phosphorus (P) on the individual leaf expansion rate and a reduced availability of assimilates for leaf growth. Simulation techniques have been used to test the hypothesis of a

  11. Limitations of shallow nets approximation.

    Science.gov (United States)

    Lin, Shao-Bo

    2017-10-01

    In this paper, we aim at analyzing the approximation abilities of shallow networks in reproducing kernel Hilbert spaces (RKHSs). We prove that there is a probability measure such that the achievable lower bound for approximating by shallow nets can be realized for all functions in balls of reproducing kernel Hilbert space with high probability, which is different with the classical minimax approximation error estimates. This result together with the existing approximation results for deep nets shows the limitations for shallow nets and provides a theoretical explanation on why deep nets perform better than shallow nets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Assimilation of Soil Wetness Index and Leaf Area Index into the ISBA-A-gs land surface model: grassland case study

    Directory of Open Access Journals (Sweden)

    A. L. Barbu

    2011-07-01

    Full Text Available The performance of the joint assimilation in a land surface model of a Soil Wetness Index (SWI product provided by an exponential filter together with Leaf Area Index (LAI is investigated. The data assimilation is evaluated with different setups using the SURFEX modeling platform, for a period of seven years (2001–2007, at the SMOSREX grassland site in southwestern France. The results obtained with a Simplified Extended Kalman Filter demonstrate the effectiveness of a joint data assimilation scheme when both SWI and Leaf Area Index are merged into the ISBA-A-gs land surface model. The assimilation of a retrieved Soil Wetness Index product presents several challenges that are investigated in this study. A significant improvement of around 13 % of the root-zone soil water content is obtained by assimilating dimensionless root-zone SWI data. For comparison, the assimilation of in situ surface soil moisture is considered as well. A lower impact on the root zone is noticed. Under specific conditions, the transfer of the information from the surface to the root zone was found not accurate. Also, our results indicate that the assimilation of in situ LAI data may correct a number of deficiencies in the model, such as low LAI values in the senescence phase by using a seasonal-dependent error definition for background and observations. In order to verify the specification of the errors for SWI and LAI products, a posteriori diagnostics are employed. This approach highlights the importance of the assimilation design on the quality of the analysis. The impact of data assimilation scheme on CO2 fluxes is also quantified by using measurements of net CO2 fluxes gathered at the SMOSREX site from 2005 to 2007. An improvement of about 5 % in terms of rms error is obtained.

  13. Shielding calculations for NET

    International Nuclear Information System (INIS)

    Verschuur, K.A.; Hogenbirk, A.

    1991-05-01

    In the European Fusion Technology Programme there is only a small activity on research and development for fusion neutronics. Never-the-less, looking further than blanket design now, as ECN is getting involved in design of radiation shields for the coils and biological shields, it becomes apparent that fusion neutronics as a whole still needs substantial development. Existing exact codes for calculation of complex geometries like MCNP and DORT/TORT are put over the limits of their numerical capabilities, whilst approximate codes for complex geometries like FURNACE and MERCURE4 are put over the limits of their modelling capabilities. The main objective of this study is just to find out how far we can get with existing codes in obtaining reliable values for the radiation levels inside and outside the cryostat/shield during operation and after shut-down. Starting with a 1D torus model for preliminary parametric studies, more dimensional approximation of the torus or parts of it including the main heterogeneities should follow. Regular contacts with the NET-Team are kept, to be aware of main changes in NET design that might affect our calculation models. Work on the contract started 1 July 1990. The technical description of the contract is given. (author). 14 refs.; 4 figs.; 1 tab

  14. Assimilation of Gridded GRACE Terrestrial Water Storage Estimates in the North American Land Data Assimilation System

    Science.gov (United States)

    Kumar, Sujay V.; Zaitchik, Benjamin F.; Peters-Lidard, Christa D.; Rodell, Matthew; Reichle, Rolf; Li, Bailing; Jasinski, Michael; Mocko, David; Getirana, Augusto; De Lannoy, Gabrielle; hide

    2016-01-01

    The objective of the North American Land Data Assimilation System (NLDAS) is to provide best available estimates of near-surface meteorological conditions and soil hydrological status for the continental United States. To support the ongoing efforts to develop data assimilation (DA) capabilities for NLDAS, the results of Gravity Recovery and Climate Experiment (GRACE) DA implemented in a manner consistent with NLDAS development are presented. Following previous work, GRACE terrestrial water storage (TWS) anomaly estimates are assimilated into the NASA Catchment land surface model using an ensemble smoother. In contrast to many earlier GRACE DA studies, a gridded GRACE TWS product is assimilated, spatially distributed GRACE error estimates are accounted for, and the impact that GRACE scaling factors have on assimilation is evaluated. Comparisons with quality-controlled in situ observations indicate that GRACE DA has a positive impact on the simulation of unconfined groundwater variability across the majority of the eastern United States and on the simulation of surface and root zone soil moisture across the country. Smaller improvements are seen in the simulation of snow depth, and the impact of GRACE DA on simulated river discharge and evapotranspiration is regionally variable. The use of GRACE scaling factors during assimilation improved DA results in the western United States but led to small degradations in the eastern United States. The study also found comparable performance between the use of gridded and basin averaged GRACE observations in assimilation. Finally, the evaluations presented in the paper indicate that GRACE DA can be helpful in improving the representation of droughts.

  15. Data Assimilation in Integrated and Distributed Hydrological Models

    DEFF Research Database (Denmark)

    Zhang, Donghua

    processes and provide simulations in refined temporal and spatial resolutions. Recent developments in measurement and sensor technologies have significantly improved the coverage, quality, frequency and diversity of hydrological observations. Data assimilation provides a great potential in relation...... point of view, different assimilation methodologies and techniques have been developed or customized to better serve hydrological assimilation. From the application point of view, real data and real-world complex catchments are used with the focus of investigating the models’ improvements with data...... a variety of model uncertainty sources and scales. Next the groundwater head assimilation experiment was tested in a much more complex catchment with assimilation of biased real observations. In such cases, the bias-aware assimilation method significantly outperforms the standard assimilation method...

  16. Dark matter assimilation into the baryon asymmetry

    International Nuclear Information System (INIS)

    D'Eramo, Francesco; Fei, Lin; Thaler, Jesse

    2012-01-01

    Pure singlets are typically disfavored as dark matter candidates, since they generically have a thermal relic abundance larger than the observed value. In this paper, we propose a new dark matter mechanism called a ssimilation , which takes advantage of the baryon asymmetry of the universe to generate the correct relic abundance of singlet dark matter. Through assimilation, dark matter itself is efficiently destroyed, but dark matter number is stored in new quasi-stable heavy states which carry the baryon asymmetry. The subsequent annihilation and late-time decay of these heavy states yields (symmetric) dark matter as well as (asymmetric) standard model baryons. We study in detail the case of pure bino dark matter by augmenting the minimal supersymmetric standard model with vector-like chiral multiplets. In the parameter range where this mechanism is effective, the LHC can discover long-lived charged particles which were responsible for assimilating dark matter

  17. Data assimilation in integrated hydrological modelling

    DEFF Research Database (Denmark)

    Rasmussen, Jørn

    Integrated hydrological models are useful tools for water resource management and research, and advances in computational power and the advent of new observation types has resulted in the models generally becoming more complex and distributed. However, the models are often characterized by a high...... degree of parameterization which results in significant model uncertainty which cannot be reduced much due to observations often being scarce and often taking the form of point measurements. Data assimilation shows great promise for use in integrated hydrological models , as it allows for observations...... to be efficiently combined with models to improve model predictions, reduce uncertainty and estimate model parameters. In this thesis, a framework for assimilating multiple observation types and updating multiple components and parameters of a catchment scale integrated hydrological model is developed and tested...

  18. Probabilistic forecasting and Bayesian data assimilation

    CERN Document Server

    Reich, Sebastian

    2015-01-01

    In this book the authors describe the principles and methods behind probabilistic forecasting and Bayesian data assimilation. Instead of focusing on particular application areas, the authors adopt a general dynamical systems approach, with a profusion of low-dimensional, discrete-time numerical examples designed to build intuition about the subject. Part I explains the mathematical framework of ensemble-based probabilistic forecasting and uncertainty quantification. Part II is devoted to Bayesian filtering algorithms, from classical data assimilation algorithms such as the Kalman filter, variational techniques, and sequential Monte Carlo methods, through to more recent developments such as the ensemble Kalman filter and ensemble transform filters. The McKean approach to sequential filtering in combination with coupling of measures serves as a unifying mathematical framework throughout Part II. Assuming only some basic familiarity with probability, this book is an ideal introduction for graduate students in ap...

  19. Data assimilation in the early phase: Kalman filtering RIMPUFF

    DEFF Research Database (Denmark)

    Astrup, P.; Turcanu, C.; Puch, R.O.

    2004-01-01

    of RODOS (Realtime Online DecisiOn Support system for nuclear emergencies) – has been developed. It is built on the Kalman filtering algorithm and it assimilates 10-minute averaged gamma dose rates measured atground level stations. Since the gamma rates are non-linear functions of the state vector...... variables, the applied Kalman filter is the so-called Extended Kalman filter. In more ways the implementation is non standard: 1) the number of state vectorvariables varies with time, and 2) the state vector variables are prediction updated with 1-minute time steps but only Kalman filtered every 10 minutes......, and this based on time averaged measurements. Given reasonable conditions, i.e. a spatially densedistribution of gamma monitors and a realistic wind field, the developed ADUM module is found to be able to enhance the prediction of the gamma dose field. Based on some of the Kalman filtering parameters, another...

  20. Data assimilation techniques in modeling ocean processes

    Digital Repository Service at National Institute of Oceanography (India)

    Mahadevan, R.; Fernandes, A.A.; Naqvi, S.W.A.

    are usually called data analysis or assimilation. These homogeneous fields are prerequisites for various practical applications and theoretical studies. The fields produced by an analysi the one hand, they must be close to the observations.... The practical usefulness of variational methods for meteorological problems are pointed out very early by Sasaki (1955, 1958), but in spite of that these methods have not been fully utilized. Probably, the complex mathematical technicality of these methods...

  1. Improving operational flood forecasting through data assimilation

    Science.gov (United States)

    Rakovec, Oldrich; Weerts, Albrecht; Uijlenhoet, Remko; Hazenberg, Pieter; Torfs, Paul

    2010-05-01

    Accurate flood forecasts have been a challenging topic in hydrology for decades. Uncertainty in hydrological forecasts is due to errors in initial state (e.g. forcing errors in historical mode), errors in model structure and parameters and last but not least the errors in model forcings (weather forecasts) during the forecast mode. More accurate flood forecasts can be obtained through data assimilation by merging observations with model simulations. This enables to identify the sources of uncertainties in the flood forecasting system. Our aim is to assess the different sources of error that affect the initial state and to investigate how they propagate through hydrological models with different levels of spatial variation, starting from lumped models. The knowledge thus obtained can then be used in a data assimilation scheme to improve the flood forecasts. This study presents the first results of this framework and focuses on quantifying precipitation errors and its effect on discharge simulations within the Ourthe catchment (1600 km2), which is situated in the Belgian Ardennes and is one of the larger subbasins of the Meuse River. Inside the catchment, hourly rain gauge information from 10 different locations is available over a period of 15 years. Based on these time series, the bootstrap method has been applied to generate precipitation ensembles. These were then used to simulate the catchment's discharges at the outlet. The corresponding streamflow ensembles were further assimilated with observed river discharges to update the model states of lumped hydrological models (R-PDM, HBV) through Residual Resampling. This particle filtering technique is a sequential data assimilation method and takes no prior assumption of the probability density function for the model states, which in contrast to the Ensemble Kalman filter does not have to be Gaussian. Our further research will be aimed at quantifying and reducing the sources of uncertainty that affect the initial

  2. A storm-time plasmasphere evolution study using data assimilation

    Science.gov (United States)

    Nikoukar, R.; Bust, G. S.; Bishop, R. L.; Coster, A. J.; Lemon, C.; Turner, D. L.; Roeder, J. L.

    2017-12-01

    In this work, we study the evolution of the Earth's plasmasphere during geomagnetic active periods using the Plasmasphere Data Assimilation (PDA) model. The total electron content (TEC) measurements from an extensive network of global ground-based GPS receivers as well as GPS receivers on-board Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) satellites and Communications/Navigation Outage Forecasting System (C/NOFS) satellite are ingested into the model. Global Core Plasma model, which is an empirical plasmasphere model, is utilized as the background model. Based on the 3D-VAR optimization, the PDA assimilative model benefits from incorporation of regularization techniques to prevent non-physical altitudinal variation in density estimates due to the limited-angle observational geometry. This work focuses on the plasmapause location, plasmasphere erosion time scales and refilling rates during the main and recovery phases of geomagnetic storms as estimated from the PDA 3-dimensional global maps of electron density in the ionosphere/plasmasphere. The comparison between the PDA results with in-situ density measurements from THEMIS and Van Allen Probes, and the RCM-E first-principle model will be also presented.

  3. Comparison of Sequential and Variational Data Assimilation

    Science.gov (United States)

    Alvarado Montero, Rodolfo; Schwanenberg, Dirk; Weerts, Albrecht

    2017-04-01

    Data assimilation is a valuable tool to improve model state estimates by combining measured observations with model simulations. It has recently gained significant attention due to its potential in using remote sensing products to improve operational hydrological forecasts and for reanalysis purposes. This has been supported by the application of sequential techniques such as the Ensemble Kalman Filter which require no additional features within the modeling process, i.e. it can use arbitrary black-box models. Alternatively, variational techniques rely on optimization algorithms to minimize a pre-defined objective function. This function describes the trade-off between the amount of noise introduced into the system and the mismatch between simulated and observed variables. While sequential techniques have been commonly applied to hydrological processes, variational techniques are seldom used. In our believe, this is mainly attributed to the required computation of first order sensitivities by algorithmic differentiation techniques and related model enhancements, but also to lack of comparison between both techniques. We contribute to filling this gap and present the results from the assimilation of streamflow data in two basins located in Germany and Canada. The assimilation introduces noise to precipitation and temperature to produce better initial estimates of an HBV model. The results are computed for a hindcast period and assessed using lead time performance metrics. The study concludes with a discussion of the main features of each technique and their advantages/disadvantages in hydrological applications.

  4. Data assimilation and model evaluation experiment datasets

    Science.gov (United States)

    Lai, Chung-Cheng A.; Qian, Wen; Glenn, Scott M.

    1994-01-01

    The Institute for Naval Oceanography, in cooperation with Naval Research Laboratories and universities, executed the Data Assimilation and Model Evaluation Experiment (DAMEE) for the Gulf Stream region during fiscal years 1991-1993. Enormous effort has gone into the preparation of several high-quality and consistent datasets for model initialization and verification. This paper describes the preparation process, the temporal and spatial scopes, the contents, the structure, etc., of these datasets. The goal of DAMEE and the need of data for the four phases of experiment are briefly stated. The preparation of DAMEE datasets consisted of a series of processes: (1) collection of observational data; (2) analysis and interpretation; (3) interpolation using the Optimum Thermal Interpolation System package; (4) quality control and re-analysis; and (5) data archiving and software documentation. The data products from these processes included a time series of 3D fields of temperature and salinity, 2D fields of surface dynamic height and mixed-layer depth, analysis of the Gulf Stream and rings system, and bathythermograph profiles. To date, these are the most detailed and high-quality data for mesoscale ocean modeling, data assimilation, and forecasting research. Feedback from ocean modeling groups who tested this data was incorporated into its refinement. Suggestions for DAMEE data usages include (1) ocean modeling and data assimilation studies, (2) diagnosis and theoretical studies, and (3) comparisons with locally detailed observations.

  5. Absorption of nitrogen by ginseng and effect of nitrogen on 14C-assimilate distribution

    International Nuclear Information System (INIS)

    Meng Xianju; Zhang Ping; Liu Tong

    1999-01-01

    By using 15 N and 14 C tracer technique, the utilization, recovery and loss rate of N fertilizer in ginseng ware studied. With different applying levels of 0, 10, 20, 30, 40 gN/m 2 14 CO 2 assimilating ability, NR activity, N compound, sugar and ginseng saponin were determined. The results showed that the N fertilizer utilization rate was 9.85% in the first year, the accumulative utilization rate for two years was 19.06%. Recovery rate of the fertilizer-N was 81.5% in the first year and 69.78% in second year. Loss rate of the fertilizer-N was 30.22%. With the treatment of 10 gN/m 2 , 14 CO 2 assimilation ability and NR activity was the highest. With the treatment of 40 gN/m 2 , total soluble sugar, sucrose and ginseng saponin content decreased and starch content increased

  6. Migration and spatial assimilation among U.S. Latinos: classical versus segmented trajectories.

    Science.gov (United States)

    South, Scott J; Crowder, Kyle; Chavez, Erick

    2005-08-01

    We used merged data from the Latino National Political Survey, the Panel Study of Income Dynamics, and the U.S. census to examine patterns and determinants of interneighborhood residential mobility between 1990 and 1995 for 2,074 U.S. residents of Mexican, Puerto Rican, and Cuban ethnicity. In several respects, our findings confirm the central tenets of spatial assimilation theory: Latino residential mobility into neighborhoods that are inhabited by greater percentages of non-Hispanic whites (i.e., Anglos) increases with human and financial capital and English-language use. However, these results also point to variations in the residential mobility process among Latinos that are broadly consistent with the segmented assimilation perspective on ethnic and immigrant incorporation. Net of controls, Puerto Ricans are less likely than Mexicans to move to neighborhoods with relatively large Anglo populations, and the generational and socioeconomic differences that are anticipated by the classical assimilation model emerge more strongly for Mexicans than for Puerto Ricans or Cubans. Among Puerto Ricans and Cubans, darker skin color inhibits mobility into Anglo neighborhoods.

  7. Thermal Effects on the Body mass, Transpiration rate, Feeding and Food Conversion of the Pillbug Armadillo officinalis (Isopoda, Oniscidea Fed on the Dry Leaf of Punica Granatum

    Directory of Open Access Journals (Sweden)

    Abdelgader K. Youssef

    2004-06-01

    Full Text Available Observations were made on the body mass; transpiration rate; assimilation efficiency; gross and net production efficiencies; feeding, assimilation, conversion and metabolic rates of the pillbug Armadillo officinalis Dumeril acclimatized at 14º  and 21 °C for 15 days and fed on the dry leaf of Punica granatum (Pomegranate.  A brief description is given on the chemical composition of P. granatum leaf.  The difference in body mass increments of A. officinalis between the acclimatized temperatures was not significant (t = 1.09; p>0.05.  However, significant differences were discernible on the transpiration rate (t = 9.53; p<0.01, moisture (t = 9.01; p<0.01, assimilation efficiency (t = 5.16; p<0.01, feeding (t = 3.76; p<0.05 and conversion (t = 2.58; p<0.05  rates between the woodlice acclimatized at 14º and 21 °C.  Better feeding of    P. granatum leaf by these animals was observed at 21° C, but better assimilation efficiency at 14 °C.  Only 3.21% assimilated food at 14° C and 6.30% at 21 °C were converted into the production of new tissues.  The food consumption of A. officinalis at 14º and 21° C was 2.05% and 3.79% body mass/day respectively.  The effect of temperature on the activity of A. officinalis in the field is discussed.

  8. The equivalency between logic Petri workflow nets and workflow nets.

    Science.gov (United States)

    Wang, Jing; Yu, ShuXia; Du, YuYue

    2015-01-01

    Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented.

  9. The Equivalency between Logic Petri Workflow Nets and Workflow Nets

    Science.gov (United States)

    Wang, Jing; Yu, ShuXia; Du, YuYue

    2015-01-01

    Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented. PMID:25821845

  10. Art/Net/Work

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik; Lindstrøm, Hanne

    2006-01-01

    The seminar Art|Net|Work deals with two important changes in our culture. On one side, the network has become essential in the latest technological development. The Internet has entered a new phase, Web 2.0, including the occurrence of as ‘Wiki’s’, ‘Peer-2-Peer’ distribution, user controlled...... on the ‘network’ itself as a phenomenon and are often using technological networks as a mean of production and distribution. This changes the artistic practice and the distribution channels of art works – and the traditional notions of ‘work’, ‘origin’ and ‘rights’ are increasingly perceived as limiting...... the praxis of the artist. We see different kinds of interventions and activism (including ‘hacktivism’) using the network as a way of questioning the invisible rules that govern public and semi-public spaces. Who ‘owns’ them? What kind of social relationships do they generate? On what principle...

  11. Net4Care

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Hansen, Klaus Marius

    2012-01-01

    , health centers are getting larger and more distributed, and the number of healthcare professionals does not follow the trend in chronic diseases. All of this leads to a need for telemedical and mobile health applications. In a Danish context, these applications are often developed through local...... (innovative) initiatives with little regards for national and global (standardization) initiatives. A reason for this discrepancy is that the software architecture for national (and global) systems and standards are hard to understand, hard to develop systems based on, and hard to deploy. To counter this, we...... propose a software ecosystem approach for telemedicine applications, providing a framework, Net4Care, encapsulating national/global design decisions with respect to standardization while allowing for local innovation. This paper presents an analysis of existing systems, of requirements for a software...

  12. Near-Net Forging Technology Demonstration Program

    Science.gov (United States)

    Hall, I. Keith

    1996-01-01

    Significant advantages in specific mechanical properties, when compared to conventional aluminum (Al) alloys, make aluminum-lithium (Al-Li) alloys attractive candidate materials for use in cryogenic propellant tanks and dry bay structures. However, the cost of Al-Li alloys is typically five times that of 2219 aluminum. If conventional fabrication processes are employed to fabricate launch vehicle structure, the material costs will restrict their utilization. In order to fully exploit the potential cost and performance benefits of Al-Li alloys, it is necessary that near-net manufacturing methods be developed to off-set or reduce raw material costs. Near-net forging is an advanced manufacturing method that uses elevated temperature metal movement (forging) to fabricate a single piece, near-net shape, structure. This process is termed 'near-net' because only a minimal amount of post-forge machining is required. The near-net forging process was developed to reduce the material scrap rate (buy-to-fly ratio) and fabrication costs associated with conventional manufacturing methods. The goal for the near-net forging process, when mature, is to achieve an overall cost reduction of approximately 50 percent compared with conventional manufacturing options for producing structures fabricated from Al-Li alloys. This NASA Marshall Space Flight Center (MSFC) sponsored program has been a part of a unique government / industry partnership, coordinated to develop and demonstrate near-net forging technology. The objective of this program was to demonstrate scale-up of the near-net forging process. This objective was successfully achieved by fabricating four integrally stiffened, 170- inch diameter by 20-inch tall, Al-Li alloy 2195, Y-ring adapters. Initially, two 2195 Al-Li ingots were converted and back extruded to produce four cylindrical blockers. Conventional ring rolling of the blockers was performed to produce ring preforms, which were then contour ring rolled to produce

  13. High-level Petri Nets

    DEFF Research Database (Denmark)

    various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets. Within the Petri net community this problem has been discussed many times, and as an outcome this book has been compiled. The book contains reprints...... of some of the most important papers on the application and theory of high-level Petri nets. In this way it makes the relevant literature more available. It is our hope that the book will be a useful source of information and that, e.g., it can be used in the organization of Petri net courses. To make......High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable descriptions than can be obtained by means...

  14. Impact of interspecific competition and drought on the allocation of new assimilates in trees.

    Science.gov (United States)

    Hommel, R; Siegwolf, R; Zavadlav, S; Arend, M; Schaub, M; Galiano, L; Haeni, M; Kayler, Z E; Gessler, A

    2016-09-01

    In trees, the interplay between reduced carbon assimilation and the inability to transport carbohydrates to the sites of demand under drought might be one of the mechanisms leading to carbon starvation. However, we largely lack knowledge on how drought effects on new assimilate allocation differ between species with different drought sensitivities and how these effects are modified by interspecific competition. We assessed the fate of (13) C labelled assimilates in above- and belowground plant organs and in root/rhizosphere respired CO2 in saplings of drought-tolerant Norway maple (Acer platanoides) and drought-sensitive European beech (Fagus sylvatica) exposed to moderate drought, either in mono- or mixed culture. While drought reduced stomatal conductance and photosynthesis rates in both species, both maintained assimilate transport belowground. Beech even allocated more new assimilate to the roots under moderate drought compared to non-limited water supply conditions, and this pattern was even more pronounced under interspecific competition. Even though maple was a superior competitor compared to beech under non-limited soil water conditions, as indicated by the changes in above- and belowground biomass of both species in the interspecific competition treatments, we can state that beech was still able to efficiently allocate new assimilate belowground under combined drought and interspecific competition. This might be seen as a strategy to maintain root osmotic potential and to prioritise root functioning. Our results thus show that beech tolerates moderate drought stress plus competition without losing its ability to supply belowground tissues. It remains to be explored in future work if this strategy is also valid during long-term drought exposure. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. Neural Net Safety Monitor Design

    Science.gov (United States)

    Larson, Richard R.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) at the Dryden Flight Research Center (DFRC) has been conducting flight-test research using an F-15 aircraft (figure 1). This aircraft has been specially modified to interface a neural net (NN) controller as part of a single-string Airborne Research Test System (ARTS) computer with the existing quad-redundant flight control system (FCC) shown in figure 2. The NN commands are passed to FCC channels 2 and 4 and are cross channel data linked (CCDL) to the other computers as shown. Numerous types of fault-detection monitors exist in the FCC when the NN mode is engaged; these monitors would cause an automatic disengagement of the NN in the event of a triggering fault. Unfortunately, these monitors still may not prevent a possible NN hard-over command from coming through to the control laws. Therefore, an additional and unique safety monitor was designed for a single-string source that allows authority at maximum actuator rates but protects the pilot and structural loads against excessive g-limits in the case of a NN hard-over command input. This additional monitor resides in the FCCs and is executed before the control laws are computed. This presentation describes a floating limiter (FL) concept1 that was developed and successfully test-flown for this program (figure 3). The FL computes the rate of change of the NN commands that are input to the FCC from the ARTS. A window is created with upper and lower boundaries, which is constantly floating and trying to stay centered as the NN command rates are changing. The limiter works by only allowing the window to move at a much slower rate than those of the NN commands. Anywhere within the window, however, full rates are allowed. If a rate persists in one direction, it will eventually hit the boundary and be rate-limited to the floating limiter rate. When this happens, a persistent counter begins and after a limit is reached, a NN disengage command is generated. The

  16. Net neutrality and audiovisual services

    OpenAIRE

    van Eijk, N.; Nikoltchev, S.

    2011-01-01

    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication networks: the control over the distribution of audiovisual services constitutes a vital part of the problem. In this contribution, the phenomenon of net neutrality is described first. Next, the European a...

  17. NetView technical research

    Science.gov (United States)

    1993-01-01

    This is the Final Technical Report for the NetView Technical Research task. This report is prepared in accordance with Contract Data Requirements List (CDRL) item A002. NetView assistance was provided and details are presented under the following headings: NetView Management Systems (NMS) project tasks; WBAFB IBM 3090; WPAFB AMDAHL; WPAFB IBM 3084; Hill AFB; McClellan AFB AMDAHL; McClellan AFB IBM 3090; and Warner-Robins AFB.

  18. Initial CAD investigations for NET

    International Nuclear Information System (INIS)

    Katz, F.; Leinemann, K.; Ludwig, A.; Marek, U.; Olbrich, W.; Schlechtendahl, E.G.

    1985-11-01

    This report summarizes the work done under contract no. 164/84-7/FU-D-/NET between the Commission of the European Communities and KfK during the period from June 1, 1984, through May 31, 1985. The following topics are covered in this report: Initial modelling of NET version NET2A, CAD system extension for remote handling studies, analysis of the CAD information structure, work related to the transfer of CAD information between KfK and the NET team. (orig.) [de

  19. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José

    2011-01-01

    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid...

  20. Valuing ecosystem services. A shadow price for net primary production

    International Nuclear Information System (INIS)

    Richmond, Amy; Kaufmann, Robert K.; Myneni, Ranga B.

    2007-01-01

    We analyze the contribution of ecosystem services to GDP and use this contribution to calculate an empirical price for ecosystem services. Net primary production is used as a proxy for ecosystem services and, along with capital and labor, is used to estimate a Cobb Douglas production function from an international panel. A positive output elasticity for net primary production probably measures both marketed and nonmarketed contributions of ecosystems services. The production function is used to calculate the marginal product of net primary production, which is the shadow price for ecosystem services. The shadow price generally is greatest for developed nations, which have larger technical scalars and use less net primary production per unit output. The rate of technical substitution indicates that the quantity of capital needed to replace a unit of net primary production tends to increase with economic development, and this rate of replacement may ultimately constrain economic growth. (author)

  1. Eddy covariance measurements of net C exchange in the CAM bioenergy crop, Agave tequiliana

    Science.gov (United States)

    Owen, Nick A.; Choncubhair, Órlaith Ní; Males, Jamie; del Real Laborde, José Ignacio; Rubio-Cortés, Ramón; Griffiths, Howard; Lanigan, Gary

    2016-04-01

    Bioenergy crop cultivation may focus more on low grade and marginal lands in order to avoid competition with food production for land and water resources. However, in many regions, this would require improvements in plant water-use efficiency that are beyond the physiological capacity of most C3 and C4 bioenergy crop candidates. Crassulacean acid metabolism (CAM) plants, such as Agave tequiliana, can combine high above-ground productivity with as little as 20% of the water demand of C3 and C4 crops. This is achieved through temporal separation of carboxylase activities, with stomata opening at night to allow gas exchange and minimise transpirational losses. Previous studies have employed 'bottom-up' methodologies to investigate carbon (C) accumulation and productivity in Agave, by scaling leaf-level gas exchange and titratable acidity (TA) with leaf area index or maximum productivity. We used the eddy covariance (EC) technique to quantify ecosystem-scale gas exchange over an Agave plantation in Mexico ('top-down' approach). Measurements were made over 252 days, including the transition from wet to dry periods. Results were cross-validated against diel changes in titratable acidity, leaf-unfurling rates, energy exchange fluxes and reported biomass yields. Net ecosystem exchange of CO2 displayed a CAM rhythm that alternated from a net C sink at night to a net C source during the day and partitioned canopy fluxes (gross C assimilation, FA,EC) showed a characteristic four-phase CO2 exchange pattern. The projected ecosystem C balance indicated that the site was a net sink of -333 ± 24 g C m-2 y-1, comprising cumulative soil respiration of 692 ± 7 g C m-2 y-1 and FA,EC of -1025 ± 25 g C m-2 y-1. EC-estimated biomass yield was 20.1 Mg ha-1 y-1. Average integrated daily FA,EC was -234 ± 5 mmol CO2 m-2 d-1 and persisted almost unchanged after 70 days of drought conditions. Our results suggest that the carbon acquisition strategy of drought avoidance employed by Agave

  2. Spatial dependence of color assimilation by the watercolor effect.

    Science.gov (United States)

    Devinck, Frédéric; Delahunt, Peter B; Hardy, Joseph L; Spillmann, Lothar; Werner, John S

    2006-01-01

    Color assimilation with bichromatic contours was quantified for spatial extents ranging from von Bezold-type color assimilation to the watercolor effect. The magnitude and direction of assimilative hue change was measured as a function of the width of a rectangular stimulus. Assimilation was quantified by hue cancellation. Large hue shifts were required to null the color of stimuli < or = 9.3 min of arc in width, with an exponential decrease for stimuli increasing up to 7.4 deg. When stimuli were viewed through an achromatizing lens, the magnitude of the assimilation effect was reduced for narrow stimuli, but not for wide ones. These results demonstrate that chromatic aberration may account, in part, for color assimilation over small, but not large, surface areas.

  3. Accelerating assimilation development for new observing systems using EFSO

    Science.gov (United States)

    Lien, Guo-Yuan; Hotta, Daisuke; Kalnay, Eugenia; Miyoshi, Takemasa; Chen, Tse-Chun

    2018-03-01

    To successfully assimilate data from a new observing system, it is necessary to develop appropriate data selection strategies, assimilating only the generally useful data. This development work is usually done by trial and error using observing system experiments (OSEs), which are very time and resource consuming. This study proposes a new, efficient methodology to accelerate the development using ensemble forecast sensitivity to observations (EFSO). First, non-cycled assimilation of the new observation data is conducted to compute EFSO diagnostics for each observation within a large sample. Second, the average EFSO conditionally sampled in terms of various factors is computed. Third, potential data selection criteria are designed based on the non-cycled EFSO statistics, and tested in cycled OSEs to verify the actual assimilation impact. The usefulness of this method is demonstrated with the assimilation of satellite precipitation data. It is shown that the EFSO-based method can efficiently suggest data selection criteria that significantly improve the assimilation results.

  4. Benefits and Pitfalls of GRACE Terrestrial Water Storage Data Assimilation

    Science.gov (United States)

    Girotto, Manuela

    2018-01-01

    Satellite observations of terrestrial water storage (TWS) from the Gravity Recovery and Climate Experiment (GRACE) mission have a coarse resolution in time (monthly) and space (roughly 150,000 sq km at midlatitudes) and vertically integrate all water storage components over land, including soil moisture and groundwater. Nonetheless, data assimilation can be used to horizontally downscale and vertically partition GRACE-TWS observations. This presentation illustrates some of the benefits and drawbacks of assimilating TWS observations from GRACE into a land surface model over the continental United States and India. The assimilation scheme yields improved skill metrics for groundwater compared to the no-assimilation simulations. A smaller impact is seen for surface and root-zone soil moisture. Further, GRACE observes TWS depletion associated with anthropogenic groundwater extraction. Results from the assimilation emphasize the importance of representing anthropogenic processes in land surface modeling and data assimilation systems.

  5. Rare, but challenging tumors: NET

    International Nuclear Information System (INIS)

    Ivanova, D.; Balev, B.

    2013-01-01

    Full text: Introduction: Gastroenteropancreatic Neuroendocrine Tumors (GEP - NET) are a heterogeneous group of tumors with different locations and many different clinical, histological, and imaging performance. In a part of them a secretion of various organic substances is present. The morbidity of GEP - NET in the EU is growing, and this leads to increase the attention to them. What you will learn: Imaging methods used for localization and staging of GEP - NET, characteristics of the study’s protocols; Classification of GEP - NET; Demonstration of typical and atypical imaging features of GEP - NET in patients registered at the NET Center at University Hospital ‘St. Marina’, Varna; Features of metastatic NET, The role of imaging in the evaluation of treatment response and follow-up of the patients. Discussion: The image semiotics analysis is based on 19 cases of GEP - NET registered NET Center at University Hospital ‘St. Marina’. The main imaging method is multidetector CT (MDCT), and magnetic resonance imaging (MRI ) has advantages in the evaluation of liver lesions and the local prevalence of anorectal tumors. In patients with advanced disease and liver lesions the assessment of skeletal involvement (MRI/ nuclear medical method) is mandatory. The majority of GEP - NET have not any specific imaging findings. Therefore it is extremely important proper planning and conducting of the study (MDCT and MR enterography; accurate assessment phase of scanning, positive and negative contrast). Conclusion: GEP - NET is a major diagnostic challenge due to the absence of typical imaging characteristics and often an overlap with those of the tumors of different origin can be observed. Therefore, a good knowledge of clinical and imaging changes occurring at different locations is needed. MDCT is the basis for the diagnosis, staging and follow-up of these neoplasms

  6. Global SWOT Data Assimilation of River Hydrodynamic Model; the Twin Simulation Test of CaMa-Flood

    Science.gov (United States)

    Ikeshima, D.; Yamazaki, D.; Kanae, S.

    2016-12-01

    CaMa-Flood is a global scale model for simulating hydrodynamics in large scale rivers. It can simulate river hydrodynamics such as river discharge, flooded area, water depth and so on by inputting water runoff derived from land surface model. Recently many improvements at parameters or terrestrial data are under process to enhance the reproducibility of true natural phenomena. However, there are still some errors between nature and simulated result due to uncertainties in each model. SWOT (Surface water and Ocean Topography) is a satellite, which is going to be launched in 2021, can measure open water surface elevation. SWOT observed data can be used to calibrate hydrodynamics model at river flow forecasting and is expected to improve model's accuracy. Combining observation data into model to calibrate is called data assimilation. In this research, we developed data-assimilated river flow simulation system in global scale, using CaMa-Flood as river hydrodynamics model and simulated SWOT as observation data. Generally at data assimilation, calibrating "model value" with "observation value" makes "assimilated value". However, the observed data of SWOT satellite will not be available until its launch in 2021. Instead, we simulated the SWOT observed data using CaMa-Flood. Putting "pure input" into CaMa-Flood produce "true water storage". Extracting actual daily swath of SWOT from "true water storage" made simulated observation. For "model value", we made "disturbed water storage" by putting "noise disturbed input" to CaMa-Flood. Since both "model value" and "observation value" are made by same model, we named this twin simulation. At twin simulation, simulated observation of "true water storage" is combined with "disturbed water storage" to make "assimilated value". As the data assimilation method, we used ensemble Kalman filter. If "assimilated value" is closer to "true water storage" than "disturbed water storage", the data assimilation can be marked effective. Also

  7. Testbed model and data assimilation for ARM

    International Nuclear Information System (INIS)

    Louis, J.F.

    1992-01-01

    The objectives of this contract are to further develop and test the ALFA (AER Local Forecast and Assimilation) model originally designed at AER for local weather prediction and apply it to three distinct but related purposes in connection with the Atmospheric Radiation Measurement (ARM) program: (a) to provide a testbed that simulates a global climate model in order to facilitate the development and testing of new cloud parametrizations and radiation models; (b) to assimilate the ARM data continuously at the scale of a climate model, using the adjoint method, thus providing the initial conditions and verification data for testing parameumtions; (c) to study the sensitivity of a radiation scheme to cloud parameters, again using the adjoint method, thus demonstrating the usefulness of the testbed model. The data assimilation will use a variational technique that minimizes the difference between the model results and the observation during the analysis period. The adjoint model is used to compute the gradient of a measure of the model errors with respect to nudging terms that are added to the equations to force the model output closer to the data. The radiation scheme that will be included in the basic ALFA model makes use of a gen two-stream approximation, and is designed for vertically inhonogeneous, multiple-scattering atmospheres. The sensitivity of this model to the definition of cloud parameters will be studied. The adjoint technique will also be used to compute the sensitivities. This project is designed to provide the Science Team members with the appropriate tools and modeling environment for proper testing and tuning of new radiation models and cloud parametrization schemes

  8. Variational data assimilation using targetted random walks

    KAUST Repository

    Cotter, S. L.

    2011-02-15

    The variational approach to data assimilation is a widely used methodology for both online prediction and for reanalysis. In either of these scenarios, it can be important to assess uncertainties in the assimilated state. Ideally, it is desirable to have complete information concerning the Bayesian posterior distribution for unknown state given data. We show that complete computational probing of this posterior distribution is now within the reach in the offline situation. We introduce a Markov chain-Monte Carlo (MCMC) method which enables us to directly sample from the Bayesian posterior distribution on the unknown functions of interest given observations. Since we are aware that these methods are currently too computationally expensive to consider using in an online filtering scenario, we frame this in the context of offline reanalysis. Using a simple random walk-type MCMC method, we are able to characterize the posterior distribution using only evaluations of the forward model of the problem, and of the model and data mismatch. No adjoint model is required for the method we use; however, more sophisticated MCMC methods are available which exploit derivative information. For simplicity of exposition, we consider the problem of assimilating data, either Eulerian or Lagrangian, into a low Reynolds number flow in a two-dimensional periodic geometry. We will show that in many cases it is possible to recover the initial condition and model error (which we describe as unknown forcing to the model) from data, and that with increasing amounts of informative data, the uncertainty in our estimations reduces. © 2011 John Wiley & Sons, Ltd.

  9. Nitrogen uptake and assimilation by corn roots

    International Nuclear Information System (INIS)

    Yoneyama, Tadakatsu; Akiyama, Yoko; Kumazawa, Kikuo

    1977-01-01

    The site of nitrogen uptake in the apical root zone of corn was experimentally investigated. Two experiments were performed. The one is to see the assimilation of nitrate and ammonium and the effects of low temperature on it. The 4-day-old roots were treated with 15 N-labelled inorganic nitrogen of 20 ppm N in 5 x 10 -4 M CaSO 4 solution at 30 deg. C and 0 deg. C. The other is to see the nitrogen uptake at apical root zone and the utilization of newly absorbed nitrogen at the root top. The 4-day-old roots were transferred into 5 x 10 -4 M CaSO 4 solution containing 15 N-labelled ammonium nitrate of 40 ppm N. As a result, the effect of low temperature on the nitrogen uptake appeared to be more drastic in the case of nitrate than ammonium. The 15 N content of amino acids indicates that ammonium is assimilated into amino acids even at 0 deg. C, but nitrate is not. The ammonium nitrogen seemed to be absorbed at both cell dividing and elongating zones. On the other hand, nitrate nitrogen seemed to be strongly absorbed at cell elongating zone. The nitrogen in the apical part may be supplied not only by direct absorption but also by translocation from the basal part. The clear difference was found in the utilization of nitrate and ammonium nitrogen at the root top when the root was elongating. This may be due to the difference of assimilation products of inorganic nitrogen. Newly absorbed ammonium nitrogen is more utilizable for the growth of root top than nitrate nitrogen. (Iwakiri, K.)

  10. Data assimilation strategies for volcano geodesy

    Science.gov (United States)

    Zhan, Yan; Gregg, Patricia M.

    2017-09-01

    Ground deformation observed using near-real time geodetic methods, such as InSAR and GPS, can provide critical information about the evolution of a magma chamber prior to volcanic eruption. Rapid advancement in numerical modeling capabilities has resulted in a number of finite element models targeted at better understanding the connection between surface uplift associated with magma chamber pressurization and the potential for volcanic eruption. Robust model-data fusion techniques are necessary to take full advantage of the numerical models and the volcano monitoring observations currently available. In this study, we develop a 3D data assimilation framework using the Ensemble Kalman Filter (EnKF) approach in order to combine geodetic observations of surface deformation with geodynamic models to investigate volcanic unrest. The EnKF sequential assimilation method utilizes disparate data sets as they become available to update geodynamic models of magma reservoir evolution. While the EnKF has been widely applied in hydrologic and climate modeling, the adaptation for volcano monitoring is in its initial stages. As such, our investigation focuses on conducting a series of sensitivity tests to optimize the EnKF for volcano applications and on developing specific strategies for assimilation of geodetic data. Our numerical experiments illustrate that the EnKF is able to adapt well to the spatial limitations posed by GPS data and the temporal limitations of InSAR, and that specific strategies can be adopted to enhance EnKF performance to improve model forecasts. Specifically, our numerical experiments indicate that: (1) incorporating additional iterations of the EnKF analysis step is more efficient than increasing the number of ensemble members; (2) the accuracy of the EnKF results are not affected by initial parameter assumptions; (3) GPS observations near the center of uplift improve the quality of model forecasts; (4) occasionally shifting continuous GPS stations to

  11. Improving carbon model phenology using data assimilation

    Science.gov (United States)

    Exrayat, Jean-François; Smallman, T. Luke; Bloom, A. Anthony; Williams, Mathew

    2015-04-01

    Carbon cycle dynamics is significantly impacted by ecosystem phenology, leading to substantial seasonal and inter-annual variation in the global carbon balance. Representing inter-annual variability is key for predicting the response of the terrestrial ecosystem to climate change and disturbance. Existing terrestrial ecosystem models (TEMs) often struggle to accurately simulate observed inter-annual variability. TEMs often use different phenological models based on plant functional type (PFT) assumptions. Moreover, due to a high level of computational overhead in TEMs they are unable to take advantage of globally available datasets to calibrate their models. Here we describe the novel CARbon DAta MOdel fraMework (CARDAMOM) for data assimilation. CARDAMOM is used to calibrate the Data Assimilation Linked Ecosystem Carbon version 2 (DALEC2) model using Bayes' Theorem within a Metropolis Hastings - Markov Chain Monte Carlo (MH-MCMC). CARDAMOM provides a framework which combines knowledge from observations, such as remotely sensed LAI, and heuristic information in the form of Ecological and Dynamical Constraints (EDCs). The EDCs are representative of real world processes and constrain parameter interdependencies and constrain carbon dynamics. We used CARDAMOM to bring together globally spanning datasets of LAI and the DALEC2 and DALEC2-GSI models. These analyses allow us to investigate the sensitivity ecosystem processes to the representation of phenology. DALEC2 uses an analytically solved model of phenology which is invariant between years. In contrast DALEC2-GSI uses a growing season index (GSI) calculated as a function of temperature, vapour pressure deficit (VPD) and photoperiod to calculate bud-burst and leaf senescence, allowing the model to simulate inter-annual variability in response to climate. Neither model makes any PFT assumptions about the phenological controls of a given ecosystem, allowing the data alone to determine the impact of the meteorological

  12. First assimilations of COSMIC radio occultation data into the Electron Density Assimilative Model (EDAM

    Directory of Open Access Journals (Sweden)

    M. J. Angling

    2008-02-01

    Full Text Available Ground based measurements of slant total electron content (TEC can be assimilated into ionospheric models to produce 3-D representations of ionospheric electron density. The Electron Density Assimilative Model (EDAM has been developed for this purpose. Previous tests using EDAM and ground based data have demonstrated that the information on the vertical structure of the ionosphere is limited in this type of data. The launch of the COSMIC satellite constellation provides the opportunity to use radio occultation data which has more vertical information. EDAM assimilations have been run for three time periods representing quiet, moderate and disturbed geomagnetic conditions. For each run, three data sets have been ingested – only ground based data, only COSMIC data and both ground based and COSMIC data. The results from this preliminary study show that both ground and space based data are capable of improving the representation of the vertical structure of the ionosphere. However, the analysis is limited by the incomplete deployment of the COSMIC constellation and the use of auto-scaled ionosonde data. The first of these can be addressed by repeating this type of study once full deployment has been achieved. The latter requires the manual scaling of ionosonde data; ideally an agreed data set would be scaled and made available to the community to facilitate comparative testing of assimilative models.

  13. Linear Logic on Petri Nets

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Winskel, Glynn

    This article shows how individual Petri nets form models of Girard's intuitionistic linear logic. It explores questions of expressiveness and completeness of linear logic with respect to this interpretation. An aim is to use Petri nets to give an understanding of linear logic and give some apprai...

  14. Net neutrality and audiovisual services

    NARCIS (Netherlands)

    van Eijk, N.; Nikoltchev, S.

    2011-01-01

    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication

  15. Development of airborne remote sensing data assimilation system

    International Nuclear Information System (INIS)

    Gudu, B R; Bi, H Y; Wang, H Y; Qin, S X; Ma, J W

    2014-01-01

    In this paper, an airborne remote sensing data assimilation system for China Airborne Remote Sensing System is introduced. This data assimilation system is composed of a land surface model, data assimilation algorithms, observation data and fundamental parameters forcing the land surface model. In this data assimilation system, Variable Infiltration Capacity hydrologic model is selected as the land surface model, which also serves as the main framework of the system. Three-dimensional variation algorithm, four-dimensional variation algorithms, ensemble Kalman filter and Particle filter algorithms are integrated in this system. Observation data includes ground observations and remotely sensed data. The fundamental forcing parameters include soil parameters, vegetation parameters and the meteorological data

  16. Boundary Conditions, Data Assimilation, and Predictability in Coastal Ocean Models

    National Research Council Canada - National Science Library

    Samelson, Roger M; Allen, John S; Egbert, Gary D; Kindle, John C; Snyder, Chris

    2007-01-01

    ...: The specific objectives of this research are to determine the impact on coastal ocean circulation models of open ocean boundary conditions from Global Ocean Data Assimilation Experiment (GODAE...

  17. Assimilation of enterprise technology upgrades: a factor-based study

    Science.gov (United States)

    Claybaugh, Craig C.; Ramamurthy, Keshavamurthy; Haseman, William D.

    2017-02-01

    The purpose of this study is to gain a better understanding of the differences in the propensity of firms to initiate and commit to the assimilation of an enterprise technology upgrade. A research model is proposed that examines the influences that four technological and four organisational factors have on predicting assimilation of a technology upgrade. Results show that firms with a greater propensity to assimilate the new enterprise resource planning (ERP) version have a higher assessment of relative advantage, IS technical competence, and the strategic role of IS relative to those firms with a lower propensity to assimilate a new ERP version.

  18. Data Assimilation of Lightning using 1D+3D/4D WRF Var Assimilation Schemes with Non-Linear Observation Operators

    Science.gov (United States)

    Navon, M. I.; Stefanescu, R.; Fuelberg, H. E.; Marchand, M.

    2012-12-01

    NASA's launch of the GOES-R Lightning Mapper (GLM) in 2015 will provide continuous, full disc, high resolution total lightning (IC + CG) data. The data will be available at a horizontal resolution of approximately 9 km. Compared to other types of data, the assimilation of lightning data into operational numerical models has received relatively little attention. Previous efforts of lightning assimilation mostly have employed nudging. This paper will describe the implementation of 1D+3D/4D Var assimilation schemes of existing ground-based WTLN (Worldwide Total Lightning Network) lightning observations using non-linear observation operators in the incremental WRFDA system. To mimic the expected output of GLM, the WTLN data were used to generate lightning super-observations characterized by flash rates/81 km2/20 min. A major difficulty associated with variational approaches is the complexity of the observation operator that defines the model equivalent of lightning. We use Convective Available Potential Energy (CAPE) as a proxy between lightning data and model variables. This operator is highly nonlinear. Marecal and Mahfouf (2003) have shown that nonlinearities can prevent direct assimilation of rainfall rates in the ECMWF 4D-VAR (using the incremental formulation proposed by Courtier et al. (1994)) from being successful. Using data from the 2011 Tuscaloosa, AL tornado outbreak, we have proved that the direct assimilation of lightning data into the WRF 3D/4D - Var systems is limited due to this incremental approach. Severe threshold limits must be imposed on the innovation vectors to obtain an improved analysis. We have implemented 1D+3D/4D Var schemes to assimilate lightning observations into the WRF model. Their use avoids innovation vector constrains from preventing the inclusion of a greater number of lightning observations Their use also minimizes the problem that nonlinearities in the moist convective scheme can introduce discontinuities in the cost function

  19. Properties of porous netted materials

    International Nuclear Information System (INIS)

    Daragan, V.D.; Drozdov, B.G.; Kotov, A.Yu.; Mel'nikov, G.N.; Pustogarov, A.V.

    1987-01-01

    Hydraulic and strength characteristics, efficient heat conduction and inner heat exchange coefficient are experimentally studied for porous netted materials on the base of the brass nets as dependent on porosity, cell size and method of net laying. Results of the studies are presented. It is shown that due to anisotropy of the material properties the hydraulic resistance in the direction parallel to the nets plane is 1.3-1.6 times higher than in the perpendicular one. Values of the effective heat conduction in the direction perpendicular to the nets plane at Π>0.45 agree with the data from literature, at Π<0.45 a deviation from the calculated values is marked in the direction of the heat conduction decrease

  20. NET remote workstation

    International Nuclear Information System (INIS)

    Leinemann, K.

    1990-10-01

    The goal of this NET study was to define the functionality of a remote handling workstation and its hardware and software architecture. The remote handling workstation has to fulfill two basic functions: (1) to provide the man-machine interface (MMI), that means the interface to the control system of the maintenance equipment and to the working environment (telepresence) and (2) to provide high level (task level) supporting functions (software tools) during the maintenance work and in the preparation phase. Concerning the man-machine interface, an important module of the remote handling workstation besides the standard components of man-machine interfacing is a module for graphical scene presentation supplementing viewing by TV. The technique of integrated viewing is well known from JET BOOM and TARM control using the GBsim and KISMET software. For integration of equipment dependent MMI functions the remote handling workstation provides a special software module interface. Task level support of the operator is based on (1) spatial (geometric/kinematic) models, (2) remote handling procedure models, and (3) functional models of the equipment. These models and the related simulation modules are used for planning, programming, execution monitoring, and training. The workstation provides an intelligent handbook guiding the operator through planned procedures illustrated by animated graphical sequences. For unplanned situations decision aids are available. A central point of the architectural design was to guarantee a high flexibility with respect to hardware and software. Therefore the remote handling workstation is designed as an open system based on widely accepted standards allowing the stepwise integration of the various modules starting with the basic MMI and the spatial simulation as standard components. (orig./HP) [de

  1. Effects of gamma radiation and temperature on the biological assimilation and retention of /sup 137/Cs by Acheta domesticus (L. )

    Energy Technology Data Exchange (ETDEWEB)

    Van Hook, Jr, R I; Herbert, E T

    1971-12-01

    Cesium-137 retention was determined for brown crickets, Acheta domesticus, which had been irradiated with 0, 1000, 2500 and 5000 rad gamma radiation and maintained at 20, 25 and 30 degrees C. Parameters examined for temperature and dose effects were (1) per cent /sup 137/Cs assimilated into body tissues (p2), (2) rate of isotope passage through the gut (k1) and (3) rate of elimination of assimilated /sup 137/Cs (ks). Increases in temperature and gamma dose resulted in a general decrease in per cent /sup 137/Cs assimilated pe day (p2). The first-component elimination coefficient (k1) was not significantly affected (P less than or equal to 0.05) by either temperature or dose changes. Biological elimination coefficients for assimilated /sup 137/Cs (k2) increased with increasing temperature between doses of 0 and 2500 rad. Above 2500 rads however, increases in temperature had no noticeable effects on the rate of assimilated /sup 137/Cs excretion. At higher dose levels, radiation was the dominant factor influencing the parameter k2.

  2. Data assimilation and PWR primary measurement

    International Nuclear Information System (INIS)

    Mercier, Thibaud

    2015-01-01

    A Pressurized Water Reactor (PWR) Reactor Coolant System (RCS) is a highly complex physical process: heterogeneous power, flow and temperature distributions are difficult to be accurately measured, since instrumentations are limited in number, thus leading to the relevant safety and protection margins. EDF R and D is seeking to assess the potential benefits of applying Data Assimilation to a PWR's RCS (Reactor Coolant System) measurements, in order to improve the estimators for parameters of a reactor's operating setpoint, i.e. improving accuracy and reducing uncertainties and biases of measured RCS parameters. In this thesis, we define a 0D semi-empirical model for RCS, satisfying the description level usually chosen by plant operators, and construct a Monte-Carlo Method (inspired from Ensemble Methods) in order to use this model with Data Assimilation tools. We apply this method on simulated data in order to assess the reduction of uncertainties on key parameters: results are beyond expectations, however strong hypothesis are required, implying a careful preprocessing of input data. (author)

  3. Data Assimilation by delay-coordinate nudging

    Science.gov (United States)

    Pazo, Diego; Lopez, Juan Manuel; Carrassi, Alberto

    2016-04-01

    A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A connection between the optimal delay and the dominant Lyapunov exponent of the dynamics is found based on heuristic arguments and is confirmed by the numerical results, providing a guideline for the practical implementation of the algorithm. Delay-coordinate nudging preserves the easiness of implementation, the intuitive functioning and the reduced computational cost of the standard nudging, making it a potential alternative especially in the field of seasonal-to-decadal predictions with large Earth system models that limit the use of more sophisticated data assimilation procedures.

  4. Turbulent viscosity optimized by data assimilation

    Directory of Open Access Journals (Sweden)

    Y. Leredde

    Full Text Available As an alternative approach to classical turbulence modelling using a first or second order closure, the data assimilation method of optimal control is applied to estimate a time and space-dependent turbulent viscosity in a three-dimensional oceanic circulation model. The optimal control method, described for a 3-D primitive equation model, involves the minimization of a cost function that quantifies the discrepancies between the simulations and the observations. An iterative algorithm is obtained via the adjoint model resolution. In a first experiment, a k + L model is used to simulate the one-dimensional development of inertial oscillations resulting from a wind stress at the sea surface and with the presence of a halocline. These results are used as synthetic observations to be assimilated. The turbulent viscosity is then recovered without the k + L closure, even with sparse and noisy observations. The problems of controllability and of the dimensions of the control are then discussed. A second experiment consists of a two-dimensional schematic simulation. A 2-D turbulent viscosity field is estimated from data on the initial and final states of a coastal upwelling event.

    Key words. Oceanography: general (numerical modelling · Oceanography: physical (turbulence · diffusion · and mixing processes

  5. Impact of Assimilation on Heavy Rainfall Simulations Using WRF Model: Sensitivity of Assimilation Results to Background Error Statistics

    Science.gov (United States)

    Rakesh, V.; Kantharao, B.

    2017-03-01

    Data assimilation is considered as one of the effective tools for improving forecast skill of mesoscale models. However, for optimum utilization and effective assimilation of observations, many factors need to be taken into account while designing data assimilation methodology. One of the critical components that determines the amount and propagation observation information into the analysis, is model background error statistics (BES). The objective of this study is to quantify how BES in data assimilation impacts on simulation of heavy rainfall events over a southern state in India, Karnataka. Simulations of 40 heavy rainfall events were carried out using Weather Research and Forecasting Model with and without data assimilation. The assimilation experiments were conducted using global and regional BES while the experiment with no assimilation was used as the baseline for assessing the impact of data assimilation. The simulated rainfall is verified against high-resolution rain-gage observations over Karnataka. Statistical evaluation using several accuracy and skill measures shows that data assimilation has improved the heavy rainfall simulation. Our results showed that the experiment using regional BES outperformed the one which used global BES. Critical thermo-dynamic variables conducive for heavy rainfall like convective available potential energy simulated using regional BES is more realistic compared to global BES. It is pointed out that these results have important practical implications in design of forecast platforms while decision-making during extreme weather events

  6. Rainfall assimilation in RAMS by means of the Kuo parameterisation inversion: method and preliminary results

    Science.gov (United States)

    Orlandi, A.; Ortolani, A.; Meneguzzo, F.; Levizzani, V.; Torricella, F.; Turk, F. J.

    2004-03-01

    In order to improve high-resolution forecasts, a specific method for assimilating rainfall rates into the Regional Atmospheric Modelling System model has been developed. It is based on the inversion of the Kuo convective parameterisation scheme. A nudging technique is applied to 'gently' increase with time the weight of the estimated precipitation in the assimilation process. A rough but manageable technique is explained to estimate the partition of convective precipitation from stratiform one, without requiring any ancillary measurement. The method is general purpose, but it is tuned for geostationary satellite rainfall estimation assimilation. Preliminary results are presented and discussed, both through totally simulated experiments and through experiments assimilating real satellite-based precipitation observations. For every case study, Rainfall data are computed with a rapid update satellite precipitation estimation algorithm based on IR and MW satellite observations. This research was carried out in the framework of the EURAINSAT project (an EC research project co-funded by the Energy, Environment and Sustainable Development Programme within the topic 'Development of generic Earth observation technologies', Contract number EVG1-2000-00030).

  7. Assimilating bio-optical glider data during a phytoplankton bloom in the southern Ross Sea

    Science.gov (United States)

    Kaufman, Daniel E.; Friedrichs, Marjorie A. M.; Hemmings, John C. P.; Smith, Walker O., Jr.

    2018-01-01

    The Ross Sea is a region characterized by high primary productivity in comparison to other Antarctic coastal regions, and its productivity is marked by considerable variability both spatially (1-50 km) and temporally (days to weeks). This variability presents a challenge for inferring phytoplankton dynamics from observations that are limited in time or space, which is often the case due to logistical limitations of sampling. To better understand the spatiotemporal variability in Ross Sea phytoplankton dynamics and to determine how restricted sampling may skew dynamical interpretations, high-resolution bio-optical glider measurements were assimilated into a one-dimensional biogeochemical model adapted for the Ross Sea. The assimilation of data from the entire glider track using the micro-genetic and local search algorithms in the Marine Model Optimization Testbed improves the model-data fit by ˜ 50 %, generating rates of integrated primary production of 104 g C m-2 yr-1 and export at 200 m of 27 g C m-2 yr-1. Assimilating glider data from three different latitudinal bands and three different longitudinal bands results in minimal changes to the simulations, improves the model-data fit with respect to unassimilated data by ˜ 35 %, and confirms that analyzing these glider observations as a time series via a one-dimensional model is reasonable on these scales. Whereas assimilating the full glider data set produces well-constrained simulations, assimilating subsampled glider data at a frequency consistent with cruise-based sampling results in a wide range of primary production and export estimates. These estimates depend strongly on the timing of the assimilated observations, due to the presence of high mesoscale variability in this region. Assimilating surface glider data subsampled at a frequency consistent with available satellite-derived data results in 40 % lower carbon export, primarily resulting from optimized rates generating more slowly sinking diatoms. This

  8. Controls on the variability of net infiltration to desert sandstone

    Science.gov (United States)

    Heilweil, Victor M.; McKinney, Tim S.; Zhdanov, Michael S.; Watt, Dennis E.

    2007-01-01

    As populations grow in arid climates and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration becomes critically important for accurately inventorying water resources and mapping contamination vulnerability. This paper presents a conceptual model of net infiltration to desert sandstone and then develops an empirical equation for its spatial quantification at the watershed scale using linear least squares inversion methods for evaluating controlling parameters (independent variables) based on estimated net infiltration rates (dependent variables). Net infiltration rates used for this regression analysis were calculated from environmental tracers in boreholes and more than 3000 linear meters of vadose zone excavations in an upland basin in southwestern Utah underlain by Navajo sandstone. Soil coarseness, distance to upgradient outcrop, and topographic slope were shown to be the primary physical parameters controlling the spatial variability of net infiltration. Although the method should be transferable to other desert sandstone settings for determining the relative spatial distribution of net infiltration, further study is needed to evaluate the effects of other potential parameters such as slope aspect, outcrop parameters, and climate on absolute net infiltration rates.

  9. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André

    2017-08-01

    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  10. Pro asynchronous programming with .NET

    CERN Document Server

    Blewett, Richard; Ltd, Rock Solid Knowledge

    2014-01-01

    Pro Asynchronous Programming with .NET teaches the essential skill of asynchronous programming in .NET. It answers critical questions in .NET application development, such as: how do I keep my program responding at all times to keep my users happy how do I make the most of the available hardware how can I improve performanceIn the modern world, users expect more and more from their applications and devices, and multi-core hardware has the potential to provide it. But it takes carefully crafted code to turn that potential into responsive, scalable applications.With Pro Asynchronous Programming

  11. Data assimilation in the decision support system RODOS

    DEFF Research Database (Denmark)

    Rojas-Palma, C.; Madsen, H.; Gering, F.

    2003-01-01

    . The process of combining model predictions and observations, usually referred to as data assimilation, is described in this article within the framework of the real time on-line decision support system (RODOS) for off-site nuclear emergency management in Europe. Data assimilation capabilities, based on Kalman...

  12. Assimilation as Attraction: Computing Distance, Similarity, and Locality in Phonology

    Science.gov (United States)

    Wayment, Adam

    2009-01-01

    This dissertation explores similarity effects in assimilation, proposing an Attraction Framework to analyze cases of parasitic harmony where a trigger-target pair only results in harmony if the trigger and target agree on other features. Attraction provides a natural model of these effects by relating the pressure for assimilation to the…

  13. Loss of protection with insecticide-treated nets against pyrethroid-resistant Culex quinquefasciatus mosquitoes once nets become holed: an experimental hut study

    Directory of Open Access Journals (Sweden)

    Irish SR

    2008-06-01

    Full Text Available Abstract Background An important advantage of pyrethroid-treated nets over untreated nets is that once nets become worn or holed a pyrethroid treatment will normally restore protection. The capacity of pyrethroids to kill or irritate any mosquito that comes into contact with the net and prevent penetration of holes or feeding through the sides are the main reasons why treated nets continue to provide protection despite their condition deteriorating over time. Pyrethroid resistance is a growing problem among Anopheline and Culicine mosquitoes in many parts of Africa. When mosquitoes become resistant the capacity of treated nets to provide protection might be diminished, particularly when holed. An experimental hut trial against pyrethroid-resistant Culex quinquefasciatus was therefore undertaken in southern Benin using a series of intact and holed nets, both untreated and treated, to assess any loss of protection as nets deteriorate with use and time. Results There was loss of protection when untreated nets became holed; the proportion of mosquitoes blood feeding increased from 36.2% when nets were intact to between 59.7% and 68.5% when nets were holed to differing extents. The proportion of mosquitoes blood feeding when treated nets were intact was 29.4% which increased to 43.6–57.4% when nets were holed. The greater the number of holes the greater the loss of protection regardless of whether nets were untreated or treated. Mosquito mortality in huts with untreated nets was 12.9–13.6%; treatment induced mortality was less than 12%. The exiting rate of mosquitoes into the verandas was higher in huts with intact nets. Conclusion As nets deteriorate with use and become increasingly holed the capacity of pyrethroid treatments to restore protection is greatly diminished against resistant Culex quinquefasciatus mosquitoes.

  14. Pattern of growth and 14C-assimilates distributions in relation to photosynthesis in radish plants treated with growth substances

    Directory of Open Access Journals (Sweden)

    Z. Starck

    2015-01-01

    Full Text Available In a series of radish plants, with very thin hypocotyl and with a normal storage organ, the rates of photosynthesis, photorespiration and dark respiration did not differ. Therefore, the conclusion may be advanced, that translocation to the swollen hypocotyl is not determinated by the photosynthetic productivity, but rather the by storage capacity. To check it this is connected with an unbalanced hormonal content, plants were treated with lanoline paste, with IAA, GA3, zeatin and all three in mixture or with injections of GA3-water solution into the swollen hypocotyl. In young radish plants, with high rate of growth of aerial parts, treatment with the above mentioned substances stimulated 14CO2-assimilation and increased retention of assimilates in 14C-donors, probably owing to retardation of their senescence. It increased the competition for photosynthates between shoot and storage organ. In older plants, in the stage of accumulation of nutrients in the swollen hypocotyl, IAA +GA3+zeatin did not affect 14CO2-assimilation, but in plants treated with growth regulators separately, assimilation decreased; IAA and GA3 stimulated transport and accumulation of labelled substances in the swollen hypocotyl. On the basis of experimental data the conclusion may be advanced that responsiveness of the particular organs and processes to growth regulators depends on the stage of plant development. Phytohormone did not changed quantitatively the pattern of 14C-assimilates distribution. They stimulated processes with preference for particular stages of development.

  15. KM3NeT

    CERN Multimedia

    KM3NeT is a large scale next-generation neutrino telescope located in the deep waters of the Mediterranean Sea, optimized for the discovery of galactic neutrino sources emitting in the TeV energy region.

  16. Pickering nuclear fish diversion net

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, J.; Lew, A. [Ontario Power Generation, Toronto, Ontario (Canada)

    2013-07-01

    Pickering Fish Diversion Net - An Engineered Environmental Solution that has significantly reduced fish impingement at the Pickering Nuclear Facility. Note: As a recent urgent request/discussed by Mark Elliot, CNE-OPG and Jacques Plourde, CNS.

  17. PolicyNet Publication System

    Data.gov (United States)

    Social Security Administration — The PolicyNet Publication System project will merge the Oracle-based Policy Repository (POMS) and the SQL-Server CAMP system (MSOM) into a new system with an Oracle...

  18. Net Neutrality: Background and Issues

    National Research Council Canada - National Science Library

    Gilroy, Angele A

    2006-01-01

    .... The move to place restrictions on the owners of the networks that compose and provide access to the Internet, to ensure equal access and nondiscriminatory treatment, is referred to as "net neutrality...

  19. The dynamic radiation environment assimilation model (DREAM)

    International Nuclear Information System (INIS)

    Reeves, Geoffrey D.; Koller, Josef; Tokar, Robert L.; Chen, Yue; Henderson, Michael G.; Friedel, Reiner H.

    2010-01-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) is a 3-year effort sponsored by the US Department of Energy to provide global, retrospective, or real-time specification of the natural and potential nuclear radiation environments. The DREAM model uses Kalman filtering techniques that combine the strengths of new physical models of the radiation belts with electron observations from long-term satellite systems such as GPS and geosynchronous systems. DREAM includes a physics model for the production and long-term evolution of artificial radiation belts from high altitude nuclear explosions. DREAM has been validated against satellites in arbitrary orbits and consistently produces more accurate results than existing models. Tools for user-specific applications and graphical displays are in beta testing and a real-time version of DREAM has been in continuous operation since November 2009.

  20. Transgenic plants that exhibit enhanced nitrogen assimilation

    Science.gov (United States)

    Coruzzi, Gloria M.; Brears, Timothy

    1999-01-01

    The present invention relates to a method for producing plants with improved agronomic and nutritional traits. Such traits include enhanced nitrogen assimilatory and utilization capacities, faster and more vigorous growth, greater vegetative and reproductive yields, and enriched or altered nitrogen content in vegetative and reproductive parts. More particularly, the invention relates to the engineering of plants modified to have altered expression of key enzymes in the nitrogen assimilation and utilization pathways. In one embodiment of the present invention, the desired altered expression is accomplished by engineering the plant for ectopic overexpression of one of more the native or modified nitrogen assimilatory enzymes. The invention also has a number of other embodiments, all of which are disclosed herein.

  1. Assimilating data into open ocean tidal models

    Science.gov (United States)

    Kivman, Gennady A.

    The problem of deriving tidal fields from observations by reason of incompleteness and imperfectness of every data set practically available has an infinitely large number of allowable solutions fitting the data within measurement errors and hence can be treated as ill-posed. Therefore, interpolating the data always relies on some a priori assumptions concerning the tides, which provide a rule of sampling or, in other words, a regularization of the ill-posed problem. Data assimilation procedures used in large scale tide modeling are viewed in a common mathematical framework as such regularizations. It is shown that they all (basis functions expansion, parameter estimation, nudging, objective analysis, general inversion, and extended general inversion), including those (objective analysis and general inversion) originally formulated in stochastic terms, may be considered as utilizations of one of the three general methods suggested by the theory of ill-posed problems. The problem of grid refinement critical for inverse methods and nudging is discussed.

  2. Polonium assimilation and retention in mule deer and pronghorn antelope

    International Nuclear Information System (INIS)

    Sejkora, K.J.

    1982-01-01

    Excretion kinetics and tissue distribution of polonium-210 in mule deer and pronghorn were studied. Each animal in a captive herd of 7 mule deer and 2 pronghorn received an intraruminal injection of 4.4 μCi of polonium chloride. Feces and urine were collected periodically over a 43-day period and daily excretion rate for each pathway was regressed as a function of time. Assimilation fractions of 0.40 and 0.51 were calculated for mule deer (n=2) and 0.60 for a pronghorn. Body burden retention functions were calculated from integrated excretion rate functions. Polonium burdens in muscle, liver, and kidney were calculated as a fraction of body burden from serially-sacrificed animals. Background tissue burdens in mule deer were comparable to those of other ruminants reported in the literature. Hypothetical cases were assumed which combined feeding rate of mule deer, forage concentrations of polonium, retention function, tissue burden fraction, and human intake to estimate human radiation dose. 26 references

  3. Net accumulation of the Greenland ice sheet

    DEFF Research Database (Denmark)

    Kiilsholm, Sissi; Christensen, Jens Hesselbjerg; Dethloff, Klaus

    2003-01-01

    High-resolution (50 km) climate change simulations for an area covering the entire Arctic have been conducted with the regional climate model (RCM) HIRHAM. The experiments were forced at the lateral boundary by large-scale atmospheric conditions from transient climate change scenario simulations...... with HIRHAM for periods representing present-day (1961-1990) and the future (2071-2100) in the two scenarios. We find that due to a much better representation of the surface topography in the RCM, the geographical distribution of present-day accumulation rates simulated by the RCM represents a substantial...... improvement compared to the driving OAGCM. Estimates of the regional net balance are also better represented by the RCM. In the future climate the net balance for the Greenland Ice Sheet is reduced in all the simulation, but discrepancies between the amounts when based on ECHAM4/OPYC3 and HIRHAM are found...

  4. NetBeans GUI Builder

    OpenAIRE

    Pusiankova, Tatsiana

    2009-01-01

    This work aims at making readers familiar with the powerful tool NetBeans IDE GUI Builder and helping them make their first steps to creation of their own graphical user interface in the Java programming language. The work includes theoretical description of NetBeans IDE GUI Builder, its most important characteristics and peculiarities and also a set of practical instructions that will help readers in creation of their first GUI. The readers will be introduced to the environment of this tool ...

  5. Recent Updates to SWANFAR (registered trademark), a 5DVAR Data Assimilation System for SWAN

    Science.gov (United States)

    2016-11-10

    inside surf zone. Blue, red, and black lines illustrate heights of small, medium, and large waves as they approach shore (from right to left). If...small, medium, or large offshore waves. Only assimilation from outside the surf zone (such as within the dashed box region) will accu- rately reflect...involv- ing a systematic and consistent examination of much larger global wave datasets and many more model simulations at global , regional, and local

  6. Multiflavor string-net models

    Science.gov (United States)

    Lin, Chien-Hung

    2017-05-01

    We generalize the string-net construction to multiple flavors of strings, each of which is labeled by the elements of an Abelian group Gi. The same flavor of strings can branch, while different flavors of strings can cross one another and thus they form intersecting string nets. We systematically construct the exactly soluble lattice Hamiltonians and the ground-state wave functions for the intersecting string-net condensed phases. We analyze the braiding statistics of the low-energy quasiparticle excitations and find that our model can realize all the topological phases as the string-net model with group G =∏iGi . In this respect, our construction provides various ways of building lattice models which realize topological order G , corresponding to different partitions of G and thus different flavors of string nets. In fact, our construction concretely demonstrates the Künneth formula by constructing various lattice models with the same topological order. As an example, we construct the G =Z2×Z2×Z2 string-net model which realizes a non-Abelian topological phase by properly intersecting three copies of toric codes.

  7. Global Distribution of Net Electron Acceptance in Subseafloor Sediment

    Science.gov (United States)

    Fulfer, V. M.; Pockalny, R. A.; D'Hondt, S.

    2017-12-01

    We quantified the global distribution of net electron acceptance rates (e-/m2/year) in subseafloor sediment (>1.5 meters below seafloor [mbsf]) using (i) a modified version of the chemical-reaction-rate algorithm by Wang et al. (2008), (ii) physical properties and dissolved oxygen and sulfate data from interstitial waters of sediment cores collected by the Ocean Drilling Program, Integrated Ocean Drilling Program, International Ocean Discovery Program, and U.S. coring expeditions, and (iii) correlation of net electron acceptance rates to global oceanographic properties. Calculated net rates vary from 4.8 x 1019 e-/m2/year for slowly accumulating abyssal clay to 1.2 x 1023 e-/m2/year for regions of high sedimentation rate. Net electron acceptance rate correlates strongly with mean sedimentation rate. Where sedimentation rate is very low (e.g., 1 m/Myr), dissolved oxygen penetrates more than 70 mbsf and is the primary terminal electron acceptor. Where sedimentation rate is moderate (e.g., 3 to 60 m/Myr), dissolved sulfate penetrates as far as 700 mbsf and is the principal terminal electron acceptor. Where sedimentation rate is high (e.g., > 60 m/Myr), dissolved sulfate penetrates only meters, but is the principal terminal electron acceptor in subseafloor sediment to the depth of sulfate penetration. Because microbial metabolism continues at greater depths than the depth of sulfate penetration in fast-accumulating sediment, complete quantification of subseafloor metabolic rates will require consideration of other chemical species.

  8. Green net national product for the sustainability and social welfare

    OpenAIRE

    Mohajan, Haradhan

    2010-01-01

    This paper discusses the theory of green national accounting and, emphasizes on social welfare and sustainable accounting. Weitzman provides a foundation for net national product as the stationary equivalent of a wealth maximizing path when there is a constant interest rate and no exogenous technological progress. An attempt has been taken here to make the relationship with different incomes and green net national product, under no exogenous technological progress and a constant utility disco...

  9. [Zr(NEtMe)2(guan-NEtMe)2] as a novel ALD precursor: ZrO2 film growth and mechanistic studies

    NARCIS (Netherlands)

    Blanquart, T.; Niinistö, J.; Aslam, N.; Banerjee, M.; Tomczak, Y.; Gavagnin, M.; Longo, V.; Puukilainen, E.; Wanzenboeck, H.D.; Kessels, W.M.M.; Devi, A.; Hoffmann-Eifert, S.; Ritala, M.; Leskelä, M.

    2013-01-01

    [Zr(NEtMe)2(guan-NEtMe2)2], a recently developed compound, was investigated as a novel precursor for the atomic layer deposition (ALD) of ZrO2. With water as the oxygen source, the growth rate remained constant over a wide temperature range, whereas with ozone the growth rate increased steadily with

  10. Solar ultraviolet-B radiation affects seedling emergence, DNA integrity, plant morphology, growth rate, and attractiveness to herbivore insects in Datura ferox

    International Nuclear Information System (INIS)

    Ballare, C.L.; Scopel, A.L.; Stapleton, A.E.

    1996-01-01

    To study functional relationships between the effects of solar ultraviolet-B radiation (UV0B) on different aspects of the physiology of a wild plant, we carried out exclusion experiments in the field with the summer annual Datura ferrox L. Solar UV-B incident over Buenos Aires reduced daytime seedling emergence, inhibited stem elongation and leaf expansion, and tended to reduce biomass accumulation during early growth. However, UV-B had no effect on calculated net assimilation rate. Using a monoclonal antibody specific to the cyclobutane-pyrimidine dimer (CPD), we found that plants receiving full sunlight had more CPDs per unit of DNA than plants shielded from solar UV-B, but the positive correlation between UV-B and CPD burden tended to level off at high (near solar) UV-B levels. At our field site, Datura plants were consumed by leaf beetles (Coleoptera), and the proportion of plants attacked by insects declined with the amount of UV-B received during growth. Field experiments showed that plant exposure to solar UV-B reduced the likelihood of leaf beetle attack by one-half. Our results highlight the complexities associated with scaling plant responses to solar UV-B, because they show: (a) a lack of correspondence between UV-B effects on net assimilation rate and whole-plant growth rate, (b) nonlinear UV-B dose-response curves, and (c) UV-B effects of plant attractiveness to natural herbivores. 56 refs., 7 figs

  11. Mass distribution of free insecticide-treated nets do not interfere with continuous net distribution in Tanzania.

    Science.gov (United States)

    Eze, Ikenna C; Kramer, Karen; Msengwa, Amina; Mandike, Renata; Lengeler, Christian

    2014-05-27

    To protect the most vulnerable groups from malaria (pregnant women and infants) the Tanzanian Government introduced a subsidy (voucher) scheme in 2004, on the basis of a public-private partnership. These vouchers are provided to pregnant women at their first antenatal care visit and mothers of infants at first vaccination. The vouchers are redeemed at registered retailers for a long-lasting insecticidal net against the payment of a modest top-up price. The present work analysed a large body of data from the Tanzanian National Voucher Scheme, focusing on interactions with concurrent mass distribution campaigns of free nets. In an ecologic study involving all regions of Tanzania, voucher redemption data for the period 2007-2011, as well as data on potential determinants of voucher redemption were analysed. The four outcome variables were: pregnant woman and infant voucher redemption rates, use of treated bed nets by all household members and by under- five children. Each of the outcomes was regressed with selected determinants, using a generalized estimating equation model and accounting for regional data clustering. There was a consistent improvement in voucher redemption rates over the selected time period, with rates >80% in 2011. The major determinants of redemption rates were the top-up price paid by the voucher beneficiary, the retailer- clinic ratio, and socio-economic status. Improved redemption rates after 2009 were most likely due to reduced top-up prices (following a change in policy). Redemption rates were not affected by two major free net distribution campaigns. During this period, there was a consistent improvement in net use across all the regions, with rates of up to 75% in 2011. The key components of the National Treated Nets Programme (NATNETS) seem to work harmoniously, leading to a high level of net use in the entire population. This calls for the continuation of this effort in Tanzania and for emulation by other countries with endemic malaria.

  12. Assimilation of stratospheric ozone in the chemical transport model STRATAQ

    Directory of Open Access Journals (Sweden)

    B. Grassi

    2004-09-01

    Full Text Available We describe a sequential assimilation approach useful for assimilating tracer measurements into a three-dimensional chemical transport model (CTM of the stratosphere. The numerical code, developed largely according to Kha00, uses parameterizations and simplifications allowing assimilation of sparse observations and the simultaneous evaluation of analysis errors, with reasonable computational requirements. Assimilation parameters are set by using χ2 and OmF (Observation minus Forecast statistics. The CTM used here is a high resolution three-dimensional model. It includes a detailed chemical package and is driven by UKMO (United Kingdom Meteorological Office analyses. We illustrate the method using assimilation of Upper Atmosphere Research Satellite/Microwave Limb Sounder (UARS/MLS ozone observations for three weeks during the 1996 antarctic spring. The comparison of results from the simulations with TOMS (Total Ozone Mapping Spectrometer measurements shows improved total ozone fields due to assimilation of MLS observations. Moreover, the assimilation gives indications on a possible model weakness in reproducing polar ozone values during springtime.

  13. Statistical techniques to extract information during SMAP soil moisture assimilation

    Science.gov (United States)

    Kolassa, J.; Reichle, R. H.; Liu, Q.; Alemohammad, S. H.; Gentine, P.

    2017-12-01

    Statistical techniques permit the retrieval of soil moisture estimates in a model climatology while retaining the spatial and temporal signatures of the satellite observations. As a consequence, the need for bias correction prior to an assimilation of these estimates is reduced, which could result in a more effective use of the independent information provided by the satellite observations. In this study, a statistical neural network (NN) retrieval algorithm is calibrated using SMAP brightness temperature observations and modeled soil moisture estimates (similar to those used to calibrate the SMAP Level 4 DA system). Daily values of surface soil moisture are estimated using the NN and then assimilated into the NASA Catchment model. The skill of the assimilation estimates is assessed based on a comprehensive comparison to in situ measurements from the SMAP core and sparse network sites as well as the International Soil Moisture Network. The NN retrieval assimilation is found to significantly improve the model skill, particularly in areas where the model does not represent processes related to agricultural practices. Additionally, the NN method is compared to assimilation experiments using traditional bias correction techniques. The NN retrieval assimilation is found to more effectively use the independent information provided by SMAP resulting in larger model skill improvements than assimilation experiments using traditional bias correction techniques.

  14. On the role of perception in shaping phonological assimilation rules.

    Science.gov (United States)

    Hura, S L; Lindblom, B; Diehl, R L

    1992-01-01

    Assimilation of nasals to the place of articulation of following consonants is a common and natural process among the world's languages. Recent phonological theory attributes this naturalness to the postulated geometry of articulatory features and the notion of spreading (McCarthy, 1988). Others view assimilation as a result of perception (Ohala, 1990), or as perceptually tolerated articulatory simplification (Kohler, 1990). Kohler notes that certain consonant classes (such as nasals and stops) are more likely than other classes (such as fricatives) to undergo place assimilation to a following consonant. To explain this pattern, he proposes that assimilation tends not to occur when the members of a consonant class are relatively distinctive perceptually, such that their articulatory reduction would be particularly salient. This explanation, of course, presupposes that the stops and nasals which undergo place assimilation are less distinctive than fricatives, which tend not to assimilate. We report experimental results that confirm Kohler's perceptual assumption: In the context of a following word initial stop, fricatives were less confusable than nasals or unreleased stops. We conclude, in agreement with Ohala and Kohler, that perceptual factors are likely to shape phonological assimilation rules.

  15. Assimilation of stratospheric ozone in the chemical transport model STRATAQ

    Directory of Open Access Journals (Sweden)

    B. Grassi

    2004-09-01

    Full Text Available We describe a sequential assimilation approach useful for assimilating tracer measurements into a three-dimensional chemical transport model (CTM of the stratosphere. The numerical code, developed largely according to Kha00, uses parameterizations and simplifications allowing assimilation of sparse observations and the simultaneous evaluation of analysis errors, with reasonable computational requirements. Assimilation parameters are set by using χ2 and OmF (Observation minus Forecast statistics. The CTM used here is a high resolution three-dimensional model. It includes a detailed chemical package and is driven by UKMO (United Kingdom Meteorological Office analyses. We illustrate the method using assimilation of Upper Atmosphere Research Satellite/Microwave Limb Sounder (UARS/MLS ozone observations for three weeks during the 1996 antarctic spring. The comparison of results from the simulations with TOMS (Total Ozone Mapping Spectrometer measurements shows improved total ozone fields due to assimilation of MLS observations. Moreover, the assimilation gives indications on a possible model weakness in reproducing polar ozone values during springtime.

  16. SMOS brightness temperature assimilation into the Community Land Model

    Directory of Open Access Journals (Sweden)

    D. Rains

    2017-11-01

    Full Text Available SMOS (Soil Moisture and Ocean Salinity mission brightness temperatures at a single incident angle are assimilated into the Community Land Model (CLM across Australia to improve soil moisture simulations. Therefore, the data assimilation system DasPy is coupled to the local ensemble transform Kalman filter (LETKF as well as to the Community Microwave Emission Model (CMEM. Brightness temperature climatologies are precomputed to enable the assimilation of brightness temperature anomalies, making use of 6 years of SMOS data (2010–2015. Mean correlation R with in situ measurements increases moderately from 0.61 to 0.68 (11 % for upper soil layers if the root zone is included in the updates. A reduced improvement of 5 % is achieved if the assimilation is restricted to the upper soil layers. Root-zone simulations improve by 7 % when updating both the top layers and root zone, and by 4 % when only updating the top layers. Mean increments and increment standard deviations are compared for the experiments. The long-term assimilation impact is analysed by looking at a set of quantiles computed for soil moisture at each grid cell. Within hydrological monitoring systems, extreme dry or wet conditions are often defined via their relative occurrence, adding great importance to assimilation-induced quantile changes. Although still being limited now, longer L-band radiometer time series will become available and make model output improved by assimilating such data that are more usable for extreme event statistics.

  17. Chromatic assimilation unaffected by perceived depth of inducing light.

    Science.gov (United States)

    Shevell, Steven K; Cao, Dingcai

    2004-01-01

    Chromatic assimilation is a shift toward the color of nearby light. Several studies conclude that a neural process contributes to assimilation but the neural locus remains in question. Some studies posit a peripheral process, such as retinal receptive-field organization, while others claim the neural mechanism follows depth perception, figure/ground segregation, or perceptual grouping. The experiments here tested whether assimilation depends on a neural process that follows stereoscopic depth perception. By introducing binocular disparity, the test field judged in color was made to appear in a different depth plane than the light that induced assimilation. The chromaticity and spatial frequency of the inducing light, and the chromaticity of the test light, were varied. Chromatic assimilation was found with all inducing-light sizes and chromaticities, but the magnitude of assimilation did not depend on the perceived relative depth planes of the test and inducing fields. We found no evidence to support the view that chromatic assimilation depends on a neural process that follows binocular combination of the two eyes' signals.

  18. Colorectal Cancer Safety Net: Is It Catching Patients Appropriately?

    Science.gov (United States)

    Althans, Alison R; Brady, Justin T; Times, Melissa L; Keller, Deborah S; Harvey, Alexis R; Kelly, Molly E; Patel, Nilam D; Steele, Scott R

    2018-01-01

    Disparities in access to colorectal cancer care are multifactorial and are affected by socioeconomic elements. Uninsured and Medicaid patients present with advanced stage disease and have worse outcomes compared with similar privately insured patients. Safety net hospitals are a major care provider to this vulnerable population. Few studies have evaluated outcomes for safety net hospitals compared with private institutions in colorectal cancer. The purpose of this study was to compare demographics, screening rates, presentation stage, and survival rates between a safety net hospital and a tertiary care center. Comparative review of patients at 2 institutions in the same metropolitan area were conducted. The study included colorectal cancer care delivered either at 1 safety net hospital or 1 private tertiary care center in the same city from 2010 to 2016. A total of 350 patients with colorectal cancer from each hospital were evaluated. Overall survival across hospital systems was measured. The safety net hospital had significantly more uninsured and Medicaid patients (46% vs 13%; p presentation, a similar percentage of patients at each hospital presented with stage IV disease (26% vs 20%; p = 0.06). For those undergoing resection, final pathologic stage distribution was similar across groups (p = 0.10). After a comparable median follow-up period (26.6 mo for safety net hospital vs 29.2 mo for tertiary care center), log-rank test for overall survival favored the safety net hospital (p = 0.05); disease-free survival was similar between hospitals (p = 0.40). This was a retrospective review, reporting from medical charts. Our results support the value of safety net hospitals for providing quality colorectal cancer care, with survival and recurrence outcomes equivalent or improved compared with a local tertiary care center. Because safety net hospitals can provide equivalent outcomes despite socioeconomic inequalities and financial constraints, emphasis should be focused

  19. Efficacy of PermaNet® 3.0 and PermaNet® 2.0 nets against laboratory-reared and wild Anopheles gambiae sensu lato populations in northern Tanzania.

    Science.gov (United States)

    Kweka, Eliningaya J; Lyaruu, Lucile J; Mahande, Aneth M

    2017-01-18

    Mosquitoes have developed resistance against pyrethroids, the only class of insecticides approved for use on long-lasting insecticidal nets (LLINs). The present study sought to evaluate the efficacy of the pyrethroid synergist PermaNet® 3.0 LLIN versus the pyrethroid-only PermaNet® 2.0 LLIN, in an East African hut design in Lower Moshi, northern Tanzania. In this setting, resistance to pyrethroid insecticides has been identified in Anopheles gambiae mosquitoes. Standard World Health Organization bioefficacy evaluations were conducted in both laboratory and experimental huts. Experimental hut evaluations were conducted in an area where there was presence of a population of highly pyrethroid-resistant An. arabiensis mosquitoes. All nets used were subjected to cone bioassays and then to experimental hut trials. Mosquito mortality, blood-feeding inhibition and personal protection rate were compared between untreated nets, unwashed LLINs and LLINs that were washed 20 times. Both washed and unwashed PermaNet® 2.0 and PermaNet® 3.0 LLINs had knockdown and mortality rates of 100% against a susceptible strain of An. gambiae sensu stricto. The adjusted mortality rate of the wild mosquito population after use of the unwashed PermaNet® 3.0 and PermaNet® 2.0 nets was found to be higher than after use of the washed PermaNet® 2.0 and PermaNet® 3.0 nets. Given the increasing incidence of pyrethroid resistance in An. gambiae mosquitoes in Tanzania, we recommend that consideration is given to its distribution in areas with pyrethroid-resistant malaria vectors within the framework of a national insecticide-resistance management plan.

  20. Effect of Vertical Canopy Architecture on Transpiration, Thermoregulation and Carbon Assimilation

    Directory of Open Access Journals (Sweden)

    Tirtha Banerjee

    2018-04-01

    Full Text Available Quantifying the impact of natural and anthropogenic disturbances such as deforestation, forest fires and vegetation thinning among others on net ecosystem—atmosphere exchanges of carbon dioxide, water vapor and heat—is an important aspect in the context of modeling global carbon, water and energy cycles. The absence of canopy architectural variation in horizontal and vertical directions is a major source of uncertainty in current climate models attempting to address these issues. This manuscript demonstrates the importance of considering the vertical distribution of foliage density by coupling a leaf level plant biophysics model with analytical solutions of wind flow and light attenuation in a horizontally homogeneous canopy. It is demonstrated that plant physiological response in terms of carbon assimilation, transpiration and canopy surface temperature can be widely different for two canopies with the same leaf area index (LAI but different leaf area density distributions, under several conditions of wind speed, light availability, soil moisture availability and atmospheric evaporative demand.

  1. The Seasonal Cycle of Water Vapour on Mars from Assimilation of Thermal Emission Spectrometer Data

    Science.gov (United States)

    Steele, Liam J.; Lewis, Stephen R.; Patel, Manish R.; Montmessin, Franck; Forget, Francois; Smith, Michael D.

    2014-01-01

    We present for the first time an assimilation of Thermal Emission Spectrometer (TES) water vapour column data into a Mars global climate model (MGCM). We discuss the seasonal cycle of water vapour, the processes responsible for the observed water vapour distribution, and the cross-hemispheric water transport. The assimilation scheme is shown to be robust in producing consistent reanalyses, and the global water vapour column error is reduced to around 2-4 pr micron depending on season. Wave activity is shown to play an important role in the water vapour distribution, with topographically steered flows around the Hellas and Argyre basins acting to increase transport in these regions in all seasons. At high northern latitudes, zonal wavenumber 1 and 2 stationary waves during northern summer are responsible for spreading the sublimed water vapour away from the pole. Transport by the zonal wavenumber 2 waves occurs primarily to the west of Tharsis and Arabia Terra and, combined with the effects of western boundary currents, this leads to peak water vapour column abundances here as observed by numerous spacecraft. A net transport of water to the northern hemisphere over the course of one Mars year is calculated, primarily because of the large northwards flux of water vapour which occurs during the local dust storm around L(sub S) = 240-260deg. Finally, outlying frost deposits that surround the north polar cap are shown to be important in creating the peak water vapour column abundances observed during northern summer.

  2. Photosynthetic pigments content, photosynthesis rate and chloroplast structure in young plants of Mikania laevigata Schultz Bip. ex Baker grown under colored netsTeores de pigmentos fotossintéticos, taxa de fotossíntese e estrutura de cloroplastos de plantas jovens de Mikania laevigata Schultz Bip. ex Baker cultivadas sob malhas coloridas

    Directory of Open Access Journals (Sweden)

    Anacleto Ranulfo dos Santos

    2011-12-01

    Full Text Available Guaco (Mikania laevigata is a medicinal plant used to treat fever, rheumatism, flu and respiratory tract diseases. Understanding the physiology of this species and its responses to environmental conditions has become necessary to improving the cultivation methods. In this context, this work aimed to access the effects of shading by using colored nets in on photosynthetic pigment concentration, photosynthetic rate and ultrastructure of chloroplasts of Mikania laevigata. The plants were cultivated during four months under nets with 50% shading in blue, red and gray color nets and under full sunlight (0%. The plants grown under full sunlight had decreased contents of a and b chlorophyll, and of carotenoids, while those grown under blue nets shown higher concentrations of a and b chlorophyll. The lowest density of chloroplasts was found in plants cultivated under full sunlight. Elongated chloroplasts were noticed in treatments with 50% shading. Regarding the potential rate of photosynthesis no significant change was observed among the plants grown under red, blue and gray nets, which leads to the conclusion that the spectrum transmitted by different coloured nets did not affect guaco photosynthetic apparatus.O guaco (Mikania laevigata é uma planta medicinal, usada para o tratamento de febre, reumatismo, gripe e doenças do trato respiratório. O entendimento do comportamento fisiológico dessa espécie e as suas respostas às condições do ambiente tornam-se necessários ao aperfeiçoamento dos métodos de cultivo. Nesse contexto, o presente trabalho teve como objetivo avaliar os efeitos do sombreamento com uso de malhas coloridas na concentração de pigmentos fotossintéticos, na taxa de fotossíntese e na ultra-estrutura de cloroplastos de plantas de Mikania laevigata. As plantas foram cultivadas por quatro meses sob malhas de 50% de sombreamento nas cores azul, vermelha e cinza e a pleno sol (0%. As plantas mantidas a pleno sol tiveram os

  3. Warmer and Wetter Soil Stimulates Assimilation More than Respiration in Rainfed Agricultural Ecosystem on the China Loess Plateau: The Role of Partial Plastic Film Mulching Tillage.

    Science.gov (United States)

    Gong, Daozhi; Hao, Weiping; Mei, Xurong; Gao, Xiang; Liu, Qi; Caylor, Kelly

    2015-01-01

    Effects of agricultural practices on ecosystem carbon storage have acquired widespread concern due to its alleviation of rising atmospheric CO2 concentrations. Recently, combining of furrow-ridge with plastic film mulching in spring maize ecosystem was widely applied to boost crop water productivity in the semiarid regions of China. However, there is still limited information about the potentials for increased ecosystem carbon storage of this tillage method. The objective of this study was to quantify and contrast net carbon dioxide exchange, biomass accumulation and carbon budgets of maize (Zea maize L.) fields under the traditional non-mulching with flat tillage (CK) and partial plastic film mulching with furrow-ridge tillage (MFR) on the China Loess Plateau. Half-hourly net ecosystem CO2 exchange (NEE) of both treatments were synchronously measured with two eddy covariance systems during the growing seasons of 2011 through 2013. At same time green leaf area index (GLAI) and biomass were also measured biweekly. Compared with CK, the warmer and wetter (+1.3°C and +4.3%) top soil at MFR accelerated the rates of biomass accumulation, promoted greater green leaf area and thus shortened the growing seasons by an average value of 10.4 days for three years. MFR stimulated assimilation more than respiration during whole growing season, resulting in a higher carbon sequestration in terms of NEE of -79 gC/m2 than CK. However, after considering carbon in harvested grain (or aboveground biomass), there is a slight higher carbon sink (or a stronger carbon source) in MFR due to its greater difference of aboveground biomass than that of grain between both treatments. These results demonstrate that partial plastic film mulched furrow-ridge tillage with aboveground biomass exclusive of grain returned to the soil is an effective way to enhance simultaneously carbon sequestration and grain yield of maize in the semiarid regions.

  4. Warmer and Wetter Soil Stimulates Assimilation More than Respiration in Rainfed Agricultural Ecosystem on the China Loess Plateau: The Role of Partial Plastic Film Mulching Tillage.

    Directory of Open Access Journals (Sweden)

    Daozhi Gong

    Full Text Available Effects of agricultural practices on ecosystem carbon storage have acquired widespread concern due to its alleviation of rising atmospheric CO2 concentrations. Recently, combining of furrow-ridge with plastic film mulching in spring maize ecosystem was widely applied to boost crop water productivity in the semiarid regions of China. However, there is still limited information about the potentials for increased ecosystem carbon storage of this tillage method. The objective of this study was to quantify and contrast net carbon dioxide exchange, biomass accumulation and carbon budgets of maize (Zea maize L. fields under the traditional non-mulching with flat tillage (CK and partial plastic film mulching with furrow-ridge tillage (MFR on the China Loess Plateau. Half-hourly net ecosystem CO2 exchange (NEE of both treatments were synchronously measured with two eddy covariance systems during the growing seasons of 2011 through 2013. At same time green leaf area index (GLAI and biomass were also measured biweekly. Compared with CK, the warmer and wetter (+1.3°C and +4.3% top soil at MFR accelerated the rates of biomass accumulation, promoted greater green leaf area and thus shortened the growing seasons by an average value of 10.4 days for three years. MFR stimulated assimilation more than respiration during whole growing season, resulting in a higher carbon sequestration in terms of NEE of -79 gC/m2 than CK. However, after considering carbon in harvested grain (or aboveground biomass, there is a slight higher carbon sink (or a stronger carbon source in MFR due to its greater difference of aboveground biomass than that of grain between both treatments. These results demonstrate that partial plastic film mulched furrow-ridge tillage with aboveground biomass exclusive of grain returned to the soil is an effective way to enhance simultaneously carbon sequestration and grain yield of maize in the semiarid regions.

  5. Plant water stress effects on the net dispersal rate of the insect vector Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) and movement of its egg parasitoid, Gonatocerus ashmeadi Girault (Hymenoptera: Mymaridae)

    Science.gov (United States)

    Homalodisca vitripennis, one of the main vectors of Xylella fastidiosa, is associated with citrus plantings in California, USA. Infested citrus orchards act as a source of vectors to adjacent vineyards where X. fastidiosa causes Pierce’s disease (PD). An analysis of the pattern and rate of movement ...

  6. Influence of a net cage tilapia culture on the water quality of the Nova Avanhandava reservoir, São Paulo State, Brazil - doi: 10.4025/actascibiolsci.v34i3.7298

    Directory of Open Access Journals (Sweden)

    André Luiz Scarano Camargo

    2012-06-01

    Full Text Available In order to understand the influence of a net cage tilapia culture on the environment, water quality parameters were investigated during the period between December, 2005 and November, 2007. Three sampling stations were established in the reservoir of Nova Avanhandava (Zacarias, São Paulo State as follows: upstream of net cage area (P1, in the rearing place (P2 and downstream of net cage area (P3. The mean values of the parameters examined in the water sampling stations were within the standards of water quality recommended by resolution no. 357/2005 of the Conselho Nacional do Meio Ambiente for class 2 freshwater bodies. A significantly higher mean concentration of total phosphorus (p -1 was the result of the uneaten feed and feces of fish. The average concentration of total phosphorus in P3 was lower (0.015 mg L-1, which was assimilated by the aquatic ecosystem. The frequent monitoring of the water parameters is fundamental, so the producer can adjust the management according to environmental conditions, by reducing fish density or changing feeding rates for example, to mitigate or avoid water quality deterioration. 

  7. Setting a price for solar net-metering in California

    OpenAIRE

    Knezevic, Laura M

    2014-01-01

    Net-metering programs are an effective policy tool for promoting investment in solar photovoltaics, yet little attention has been paid to the rate at which excess energy generation is credited until recently. Like most States, California customers who participate in net-metering receive a credit for excess generation at the current retail rate for electricity. This buy-back rate does not take into account the value of solar energy to the utility or the costs to the customer of purchasing an...

  8. Development of an Operational TS Dataset Production System for the Data Assimilation System

    Science.gov (United States)

    Kim, Sung Dae; Park, Hyuk Min; Kim, Young Ho; Park, Kwang Soon

    2017-04-01

    An operational TS (Temperature and Salinity) dataset production system was developed to provide near real-time data to the data assimilation system periodically. It collects the latest 15 days' TS data of the north western pacific area (20°N - 55°N, 110°E - 150°E), applies QC tests to the archived data and supplies them to numerical prediction models of KIOST (Korea Institute of Ocean Science and Technology). The latest real-time TS data are collected from Argo GDAC and GTSPP data server every week. Argo data are downloaded from /latest_data directory of Argo GDAC. Because many duplicated data exist when all profile data are extracted from all Argo netCDF files, DB system is used to avoid duplication. All metadata (float ID, location, observation date and time, etc) of all Argo floats is stored into Database system and a Matlab program was developed to manipulate DB data, to check the duplication and to exclude duplicated data. GTSPP data are downloaded from /realtime directory of GTSPP data service. The latest data except ARGO data are extracted from the original data. Another Matlab program was coded to inspect all collected data using 10 QC tests and produce final dataset which can be used by the assimilation system. Three regional range tests to inspect annual, seasonal and monthly variations are included in the QC procedures. The C program was developed to provide regional ranges to data managers. It can calculate upper limit and lower limit of temperature and salinity at depth from 0 to 1550m. The final TS dataset contains the latest 15 days' TS data in netCDF format. It is updated every week and transmitted to numerical modeler of KIOST for operational use.

  9. A case study of GWE satellite data impact on GLA assimilation analyses of two ocean cyclones

    Science.gov (United States)

    Gallimore, R. G.; Johnson, D. R.

    1986-01-01

    The effects of the Global Weather Experiment (GWE) data obtained on January 18-20, 1979 on Goddard Laboratory for Atmospheres assimilation analyses of simultaneous cyclones in the western Pacific and Atlantic oceans are examined. The ability of satellite data within assimilation models to determine the baroclinic structures of developing extratropical cyclones is evaluated. The impact of the satellite data on the amplitude and phase of the temperature structure within the storm domain, potential energy, and baroclinic growth rate is studied. The GWE data are compared with Data Systems Test results. It is noted that it is necessary to characterize satellite effects on the baroclinic structure of cyclone waves which degrade numerical weather predictions of cyclogenesis.

  10. Towards a Comprehensive Dynamic-chemistry Assimilation for Eos-Chem: Plans and Status in NASA's Data Assimilation Office

    Science.gov (United States)

    Pawson, Steven; Lin, Shian-Jiann; Rood, Richard B.; Stajner, Ivanka; Nebuda, Sharon; Nielsen, J. Eric; Douglass, Anne R.

    2000-01-01

    In order to support the EOS-Chem project, a comprehensive assimilation package for the coupled chemical-dynamical system is being developed by the Data Assimilation Office at NASA GSFC. This involves development of a coupled chemistry/meteorology model and of data assimilation techniques for trace species and meteorology. The model is being developed using the flux-form semi-Lagrangian dynamical core of Lin and Rood, the physical parameterizations from the NCAR Community Climate Model, and atmospheric chemistry modules from the Atmospheric Chemistry and Dynamics branch at NASA GSFC. To date the following results have been obtained: (i) multi-annual simulations with the dynamics-radiation model show the credibility of the package for atmospheric simulations; (ii) initial simulations including a limited number of middle atmospheric trace gases reveal the realistic nature of transport mechanisms, although there is still a need for some improvements. Samples of these results will be shown. A meteorological assimilation system is currently being constructed using the model; this will form the basis for the proposed meteorological/chemical assimilation package. The latter part of the presentation will focus on areas targeted for development in the near and far terms, with the objective of Providing a comprehensive assimilation package for the EOS-Chem science experiment. The first stage will target ozone assimilation. The plans also encompass a reanalysis (ReSTS) for the 1991-1995 period, which includes the Mt. Pinatubo eruption and the time when a large number of UARS observations were available. One of the most challenging aspects of future developments will be to couple theoretical advances in tracer assimilation with the practical considerations of a real environment and eventually a near-real-time assimilation system.

  11. MATT: Multi Agents Testing Tool Based Nets within Nets

    Directory of Open Access Journals (Sweden)

    Sara Kerraoui

    2016-12-01

    As part of this effort, we propose a model based testing approach for multi agent systems based on such a model called Reference net, where a tool, which aims to providing a uniform and automated approach is developed. The feasibility and the advantage of the proposed approach are shown through a short case study.

  12. Implementing NetScaler VPX

    CERN Document Server

    Sandbu, Marius

    2014-01-01

    An easy-to-follow guide with detailed step-by step-instructions on how to implement the different key components in NetScaler, with real-world examples and sample scenarios.If you are a Citrix or network administrator who needs to implement NetScaler in your virtual environment to gain an insight on its functionality, this book is ideal for you. A basic understanding of networking and familiarity with some of the different Citrix products such as XenApp or XenDesktop is a prerequisite.

  13. Net4Care PHMR Library

    DEFF Research Database (Denmark)

    2014-01-01

    The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the SimpleClinicalDocument......The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the Simple...

  14. Net present value approaches for drug discovery.

    Science.gov (United States)

    Svennebring, Andreas M; Wikberg, Jarl Es

    2013-12-01

    Three dedicated approaches to the calculation of the risk-adjusted net present value (rNPV) in drug discovery projects under different assumptions are suggested. The probability of finding a candidate drug suitable for clinical development and the time to the initiation of the clinical development is assumed to be flexible in contrast to the previously used models. The rNPV of the post-discovery cash flows is calculated as the probability weighted average of the rNPV at each potential time of initiation of clinical development. Practical considerations how to set probability rates, in particular during the initiation and termination of a project is discussed.

  15. Efficient data assimilation algorithm for bathymetry application

    Science.gov (United States)

    Ghorbanidehno, H.; Lee, J. H.; Farthing, M.; Hesser, T.; Kitanidis, P. K.; Darve, E. F.

    2017-12-01

    Information on the evolving state of the nearshore zone bathymetry is crucial to shoreline management, recreational safety, and naval operations. The high cost and complex logistics of using ship-based surveys for bathymetry estimation have encouraged the use of remote sensing techniques. Data assimilation methods combine the remote sensing data and nearshore hydrodynamic models to estimate the unknown bathymetry and the corresponding uncertainties. In particular, several recent efforts have combined Kalman Filter-based techniques such as ensembled-based Kalman filters with indirect video-based observations to address the bathymetry inversion problem. However, these methods often suffer from ensemble collapse and uncertainty underestimation. Here, the Compressed State Kalman Filter (CSKF) method is used to estimate the bathymetry based on observed wave celerity. In order to demonstrate the accuracy and robustness of the CSKF method, we consider twin tests with synthetic observations of wave celerity, while the bathymetry profiles are chosen based on surveys taken by the U.S. Army Corps of Engineer Field Research Facility (FRF) in Duck, NC. The first test case is a bathymetry estimation problem for a spatially smooth and temporally constant bathymetry profile. The second test case is a bathymetry estimation problem for a temporally evolving bathymetry from a smooth to a non-smooth profile. For both problems, we compare the results of CSKF with those obtained by the local ensemble transform Kalman filter (LETKF), which is a popular ensemble-based Kalman filter method.

  16. Efficient Data Assimilation Algorithms for Bathymetry Applications

    Science.gov (United States)

    Ghorbanidehno, H.; Kokkinaki, A.; Lee, J. H.; Farthing, M.; Hesser, T.; Kitanidis, P. K.; Darve, E. F.

    2016-12-01

    Information on the evolving state of the nearshore zone bathymetry is crucial to shoreline management, recreational safety, and naval operations. The high cost and complex logistics of using ship-based surveys for bathymetry estimation have encouraged the use of remote sensing monitoring. Data assimilation methods combine monitoring data and models of nearshore dynamics to estimate the unknown bathymetry and the corresponding uncertainties. Existing applications have been limited to the basic Kalman Filter (KF) and the Ensemble Kalman Filter (EnKF). The former can only be applied to low-dimensional problems due to its computational cost; the latter often suffers from ensemble collapse and uncertainty underestimation. This work explores the use of different variants of the Kalman Filter for bathymetry applications. In particular, we compare the performance of the EnKF to the Unscented Kalman Filter and the Hierarchical Kalman Filter, both of which are KF variants for non-linear problems. The objective is to identify which method can better handle the nonlinearities of nearshore physics, while also having a reasonable computational cost. We present two applications; first, the bathymetry of a synthetic one-dimensional cross section normal to the shore is estimated from wave speed measurements. Second, real remote measurements with unknown error statistics are used and compared to in situ bathymetric survey data collected at the USACE Field Research Facility in Duck, NC. We evaluate the information content of different data sets and explore the impact of measurement error and nonlinearities.

  17. Coloured Petri Nets and the Invariant Method

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1981-01-01

    processes to be described by a common subnet, without losing the ability to distinguish between them. Our generalization, called coloured Petri nets, is heavily influenced by predicate transition-nets introduced by H.J. Genrich and K. Lautenbach. Moreover our paper shows how the invariant-method, introduced...... for Petri nets by K. Lautenbach, can be generalized to coloured Petri nets....

  18. Assimilate unloading from maize (Zea mays L.) pedicel tissues

    International Nuclear Information System (INIS)

    Porter, G.A.; Knievel, D.P.; Shannon, J.C.

    1987-01-01

    Sugar and 14 C-assimilate release from the pedicel tissue of attached maize (Zea mays L.) kernels was studied following treatment with solute concentrations of up to 800 millimolal. Exposure and collection times ranged from 3 to 6 hours. Sugar and 14 C-assimilate unloading and collection in agar traps was reduced by 25 and 43%, respectively, following exposure to 800 millimolal mannitol. Inhibition of unloading was not specific to mannitol, since similar concentrations of glucose, fructose, or equimolar glucose plus fructose resulted in comparable inhibition. Ethylene glycol, a rapidly permeating solute which should not greatly influence cell turgor, did not inhibit 14 C-assimilate unloading. Based on these results, they suggest that inhibition of unloading by high concentrations of sugar or mannitol was due to reduced pedicel cell turgor. Changes in pedicel cell turgor may play a role in the regulation of assimilate transfer within the maize kernel

  19. Develop a Hybrid Coordinate Ocean Model with Data Assimilation Capabilities

    National Research Council Canada - National Science Library

    Thacker, W. C

    2003-01-01

    .... The objectives of the research are as follows: (1) to develop a methodology for assimilating temperature and salinity profiles from XBT, CTD, and ARGO float data that accommodates the peculiarities of HYCOM's hybrid vertical coordinates, allowing...

  20. Regional Ocean Modeling System (ROMS): CNMI: Data Assimilating

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 3-day, 3-hourly data assimilating hindcast for the region surrounding the Commonwealth of the Northern Mariana Islands (CNMI)...

  1. A simple lightning assimilation technique for improving retrospective WRF simulations.

    Science.gov (United States)

    Convective rainfall is often a large source of error in retrospective modeling applications. In particular, positive rainfall biases commonly exist during summer months due to overactive convective parameterizations. In this study, lightning assimilation was applied in the Kain-F...

  2. Data assimilation in modeling ocean processes: A bibliographic study

    Digital Repository Service at National Institute of Oceanography (India)

    Mahadevan, R.; Fernandes, A.A.; Saran, A.K.

    An annotated bibliography on studies related to data assimilation in modeling ocean processes has been prepared. The bibliography listed here is not comprehensive and is not prepared from the original references. Information obtainable from...

  3. Air Quality Activities in the Global Modeling and Assimilation Office

    Science.gov (United States)

    Pawson, Steven

    2016-01-01

    GMAO's mission is to enhance the use of NASA's satellite observations in weather and climate modeling. This presentation will be discussing GMAO's mission, value of data assimilation, and some relevant (available) GMAO data products.

  4. UARS Correlative UKMO Daily Gridded Stratospheric Assimilated Data V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The UARS Correlative assimilation data from the U.K. Meteorological Office (UKMO) consists of daily model runs at 12:00 GMT as a means of providing an independent...

  5. Regional Ocean Modeling System (ROMS): Samoa: Data Assimilating

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 3-day, 3-hourly data assimilating hindcast for the region surrounding the islands of Samoa at approximately 3-km resolution....

  6. Regional Ocean Modeling System (ROMS): Main Hawaiian Islands: Data Assimilating

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 3-day, 3-hourly data assimilating hindcast for the region surrounding the main Hawaiian islands at approximately 4-km...

  7. The Culure Assimilator: An Approach to Cross-Cultural Training

    Science.gov (United States)

    Fiedler, Fred E.; And Others

    1971-01-01

    Evaluates the cultural assimilator, a kind of training manual to help members of one culture understand and adjust to another culture. Describes those constructed for the Arab countries, Iran, Thailand, Central America, and Greece. (MB)

  8. Regional Ocean Modeling System (ROMS): Oahu: Data Assimilating

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 2-day, 3-hourly data assimilating hindcast for the region surrounding the island of Oahu at approximately 1-km resolution....

  9. Assimilation of Aircraft Observations in High-Resolution Mesoscale Modeling

    Directory of Open Access Journals (Sweden)

    Brian P. Reen

    2018-01-01

    Full Text Available Aircraft-based observations are a promising source of above-surface observations for assimilation into mesoscale model simulations. The Tropospheric Airborne Meteorological Data Reporting (TAMDAR observations have potential advantages over some other aircraft observations including the presence of water vapor observations. The impact of assimilating TAMDAR observations via observation nudging in 1 km horizontal grid spacing Weather Research and Forecasting model simulations is evaluated using five cases centered over California. Overall, the impact of assimilating the observations is mixed, with the layer with the greatest benefit being above the surface in the lowest 1000 m above ground level and the variable showing the most consistent benefit being temperature. Varying the nudging configuration demonstrates the sensitivity of the results to details of the assimilation, but does not clearly demonstrate the superiority of a specific configuration.

  10. Satellite Sounder Data Assimilation for Improving Alaska Region Weather Forecast

    Science.gov (United States)

    Zhu, Jiang; Stevens, E.; Zavodsky, B. T.; Zhang, X.; Heinrichs, T.; Broderson, D.

    2014-01-01

    Data assimilation has been demonstrated very useful in improving both global and regional numerical weather prediction. Alaska has very coarser surface observation sites. On the other hand, it gets much more satellite overpass than lower 48 states. How to utilize satellite data to improve numerical prediction is one of hot topics among weather forecast community in Alaska. The Geographic Information Network of Alaska (GINA) at University of Alaska is conducting study on satellite data assimilation for WRF model. AIRS/CRIS sounder profile data are used to assimilate the initial condition for the customized regional WRF model (GINA-WRF model). Normalized standard deviation, RMSE, and correlation statistic analysis methods are applied to analyze one case of 48 hours forecasts and one month of 24-hour forecasts in order to evaluate the improvement of regional numerical model from Data assimilation. The final goal of the research is to provide improved real-time short-time forecast for Alaska regions.

  11. High success rates of sedation-free brain MRI scanning in young children using simple subject preparation protocols with and without a commercial mock scanner–the Diabetes Research in Children Network (DirecNet) experience

    Science.gov (United States)

    Barnea-Goraly, Naama; Weinzimer, Stuart A.; Mauras, Nelly; Beck, Roy W.; Marzelli, Matt J.; Mazaika, Paul K.; Aye, Tandy; White, Neil H.; Tsalikian, Eva; Fox, Larry; Kollman, Craig; Cheng, Peiyao; Reiss, Allan L.

    2013-01-01

    Background The ability to lie still in an MRI scanner is essential for obtaining usable image data. To reduce motion, young children are often sedated, adding significant cost and risk. Objective We assessed the feasibility of using a simple and affordable behavioral desensitization program to yield high-quality brain MRI scans in sedation-free children. Materials and methods 222 children (4–9.9 years), 147 with type 1 diabetes and 75 age-matched non-diabetic controls, participated in a multi-site study focused on effects of type 1 diabetes on the developing brain. T1-weighted and diffusion-weighted imaging (DWI) MRI scans were performed. All children underwent behavioral training and practice MRI sessions using either a commercial MRI simulator or an inexpensive mock scanner consisting of a toy tunnel, vibrating mat, and video player to simulate the sounds and feel of the MRI scanner. Results 205 children (92.3%), mean age 7±1.7 years had high-quality T1-W scans and 174 (78.4%) had high-quality diffusion-weighted scans after the first scan session. With a second scan session, success rates were 100% and 92.5% for T1-and diffusion-weighted scans, respectively. Success rates did not differ between children with type 1 diabetes and children without diabetes, or between centers using a commercial MRI scan simulator and those using the inexpensive mock scanner. Conclusion Behavioral training can lead to a high success rate for obtaining high-quality T1-and diffusion-weighted brain images from a young population without sedation. PMID:24096802

  12. High success rates of sedation-free brain MRI scanning in young children using simple subject preparation protocols with and without a commercial mock scanner-the Diabetes Research in Children Network (DirecNet) experience

    International Nuclear Information System (INIS)

    Barnea-Goraly, Naama; Marzelli, Matt J.; Mazaika, Paul K.; Weinzimer, Stuart A.; Ruedy, Katrina J.; Beck, Roy W.; Kollman, Craig; Cheng, Peiyao; Mauras, Nelly; Fox, Larry; Aye, Tandy; White, Neil H.; Tsalikian, Eva; Reiss, Allan L.

    2014-01-01

    The ability to lie still in an MRI scanner is essential for obtaining usable image data. To reduce motion, young children are often sedated, adding significant cost and risk. We assessed the feasibility of using a simple and affordable behavioral desensitization program to yield high-quality brain MRI scans in sedation-free children. 222 children (4-9.9 years), 147 with type 1 diabetes and 75 age-matched non-diabetic controls, participated in a multi-site study focused on effects of type 1 diabetes on the developing brain. T1-weighted and diffusion-weighted imaging (DWI) MRI scans were performed. All children underwent behavioral training and practice MRI sessions using either a commercial MRI simulator or an inexpensive mock scanner consisting of a toy tunnel, vibrating mat, and video player to simulate the sounds and feel of the MRI scanner. 205 children (92.3%), mean age 7 ± 1.7 years had high-quality T1-W scans and 174 (78.4%) had high-quality diffusion-weighted scans after the first scan session. With a second scan session, success rates were 100% and 92.5% for T1-and diffusion-weighted scans, respectively. Success rates did not differ between children with type 1 diabetes and children without diabetes, or between centers using a commercial MRI scan simulator and those using the inexpensive mock scanner. Behavioral training can lead to a high success rate for obtaining high-quality T1-and diffusion-weighted brain images from a young population without sedation. (orig.)

  13. High success rates of sedation-free brain MRI scanning in young children using simple subject preparation protocols with and without a commercial mock scanner-the Diabetes Research in Children Network (DirecNet) experience

    Energy Technology Data Exchange (ETDEWEB)

    Barnea-Goraly, Naama; Marzelli, Matt J.; Mazaika, Paul K. [Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford, CA (United States); Weinzimer, Stuart A. [Yale University, Pediatric Endocrinology, New Haven, CT (United States); Ruedy, Katrina J.; Beck, Roy W.; Kollman, Craig; Cheng, Peiyao [Jaeb Center for Health Research, Tampa, FL (United States); Mauras, Nelly; Fox, Larry [Nemours Children' s Clinic, Pediatric Endocrinology, Jacksonville, FL (United States); Aye, Tandy [Stanford University, Department of Pediatrics, Stanford, CA (United States); White, Neil H. [Washington University in St. Louis, Department of Pediatrics, St. Louis, MO (United States); Tsalikian, Eva [University of Iowa, Pediatric Endocrinology, Iowa City, IA (United States); Reiss, Allan L. [Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford, CA (United States); Stanford University, Department of Pediatrics, Stanford, CA (United States); Stanford University, Department of Radiology, Diabetes Research in Children Network (DirecNet), Stanford, CA (United States); Collaboration: on behalf of the Diabetes Research in Children Network (DirecNet)

    2014-02-15

    The ability to lie still in an MRI scanner is essential for obtaining usable image data. To reduce motion, young children are often sedated, adding significant cost and risk. We assessed the feasibility of using a simple and affordable behavioral desensitization program to yield high-quality brain MRI scans in sedation-free children. 222 children (4-9.9 years), 147 with type 1 diabetes and 75 age-matched non-diabetic controls, participated in a multi-site study focused on effects of type 1 diabetes on the developing brain. T1-weighted and diffusion-weighted imaging (DWI) MRI scans were performed. All children underwent behavioral training and practice MRI sessions using either a commercial MRI simulator or an inexpensive mock scanner consisting of a toy tunnel, vibrating mat, and video player to simulate the sounds and feel of the MRI scanner. 205 children (92.3%), mean age 7 ± 1.7 years had high-quality T1-W scans and 174 (78.4%) had high-quality diffusion-weighted scans after the first scan session. With a second scan session, success rates were 100% and 92.5% for T1-and diffusion-weighted scans, respectively. Success rates did not differ between children with type 1 diabetes and children without diabetes, or between centers using a commercial MRI scan simulator and those using the inexpensive mock scanner. Behavioral training can lead to a high success rate for obtaining high-quality T1-and diffusion-weighted brain images from a young population without sedation. (orig.)

  14. Household economic modelsof gill net fishermen at Madura strait

    Science.gov (United States)

    Primyastanto, M.

    2018-04-01

    The purposes of this research was to analyze household economic models of gill net fishermen at Madura strait. 30 families of gillnet fishermenwere used for purposive sampling. Data analysis used descriptive qualitative and quantitative (regression analysis). Quantitative descriptive analysis was used to analyze research and compare to factors that affecting household economic models of gill net fishermen family. Research results showed tha thousehold economic models of gill net fishermen at Madura strait was production value level or fishermen revenue at sea was strongly influenced byp roduction asset production, education level, fuel, and work flow. Work flow rate of fishermen families affected by asset production, non fisheries workflow and number of male workforce. Non fishing income level was strongly influenced by non-fishery business assets, number of family members owned andnon-fishing work flow. Spending levels of gill net fishermen at Madura strait was affected by fishing income, non-fishing income, fishermen wife education and fishermen family members.

  15. Multi-parametric variational data assimilation for hydrological forecasting

    Science.gov (United States)

    Alvarado-Montero, R.; Schwanenberg, D.; Krahe, P.; Helmke, P.; Klein, B.

    2017-12-01

    Ensemble forecasting is increasingly applied in flow forecasting systems to provide users with a better understanding of forecast uncertainty and consequently to take better-informed decisions. A common practice in probabilistic streamflow forecasting is to force deterministic hydrological model with an ensemble of numerical weather predictions. This approach aims at the representation of meteorological uncertainty but neglects uncertainty of the hydrological model as well as its initial conditions. Complementary approaches use probabilistic data assimilation techniques to receive a variety of initial states or represent model uncertainty by model pools instead of single deterministic models. This paper introduces a novel approach that extends a variational data assimilation based on Moving Horizon Estimation to enable the assimilation of observations into multi-parametric model pools. It results in a probabilistic estimate of initial model states that takes into account the parametric model uncertainty in the data assimilation. The assimilation technique is applied to the uppermost area of River Main in Germany. We use different parametric pools, each of them with five parameter sets, to assimilate streamflow data, as well as remotely sensed data from the H-SAF project. We assess the impact of the assimilation in the lead time performance of perfect forecasts (i.e. observed data as forcing variables) as well as deterministic and probabilistic forecasts from ECMWF. The multi-parametric assimilation shows an improvement of up to 23% for CRPS performance and approximately 20% in Brier Skill Scores with respect to the deterministic approach. It also improves the skill of the forecast in terms of rank histogram and produces a narrower ensemble spread.

  16. Ethnicity, assimilation and harassment in the labor market

    OpenAIRE

    Epstein, Gil S.; Gang, Ira N.

    2008-01-01

    We often observe minority ethnic groups at a disadvantage relative to the majority. Why is this and what can be done about it? Efforts made to assimilate, and time, are two elements working to bring the minority into line with the majority. A third element, the degree to which the majority welcomes the minority, also plays a role. We develop a simple theoretical model useful for examining the consequences for assimilation and harassment of growth in the minority population, time, and the role...

  17. Joint Center for Satellite Data Assimilation Overview and Research Activities

    Science.gov (United States)

    Auligne, T.

    2017-12-01

    In 2001 NOAA/NESDIS, NOAA/NWS, NOAA/OAR, and NASA, subsequently joined by the US Navy and Air Force, came together to form the Joint Center for Satellite Data Assimilation (JCSDA) for the common purpose of accelerating the use of satellite data in environmental numerical prediction modeling by developing, using, and anticipating advances in numerical modeling, satellite-based remote sensing, and data assimilation methods. The primary focus was to bring these advances together to improve operational numerical model-based forecasting, under the premise that these partners have common technical and logistical challenges assimilating satellite observations into their modeling enterprises that could be better addressed through cooperative action and/or common solutions. Over the last 15 years, the JCSDA has made and continues to make major contributions to operational assimilation of satellite data. The JCSDA is a multi-agency U.S. government-owned-and-operated organization that was conceived as a venue for the several agencies NOAA, NASA, USAF and USN to collaborate on advancing the development and operational use of satellite observations into numerical model-based environmental analysis and forecasting. The primary mission of the JCSDA is to "accelerate and improve the quantitative use of research and operational satellite data in weather, ocean, climate and environmental analysis and prediction systems." This mission is fulfilled through directed research targeting the following key science objectives: Improved radiative transfer modeling; new instrument assimilation; assimilation of humidity, clouds, and precipitation observations; assimilation of land surface observations; assimilation of ocean surface observations; atmospheric composition; and chemistry and aerosols. The goal of this presentation is to briefly introduce the JCSDA's mission and vision, and to describe recent research activities across various JCSDA partners.

  18. D.NET case study

    International Development Research Centre (IDRC) Digital Library (Canada)

    lremy

    The mission was defined to build, “A society where information and ... innovative ideas and projects around different themes (using ICT), and piloting them to test .... like D.Net with several projects that had moved beyond their pilot phase.

  19. Petri Nets in Cryptographic Protocols

    DEFF Research Database (Denmark)

    Crazzolara, Federico; Winskel, Glynn

    2001-01-01

    A process language for security protocols is presented together with a semantics in terms of sets of events. The denotation of process is a set of events, and as each event specifies a set of pre and postconditions, this denotation can be viewed as a Petri net. By means of an example we illustrate...

  20. Complexity metrics for workflow nets

    NARCIS (Netherlands)

    Lassen, K.B.; Aalst, van der W.M.P.

    2009-01-01

    Process modeling languages such as EPCs, BPMN, flow charts, UML activity diagrams, Petri nets, etc., are used to model business processes and to configure process-aware information systems. It is known that users have problems understanding these diagrams. In fact, even process engineers and system

  1. Reference Guide Microsoft.NET

    NARCIS (Netherlands)

    Zee M van der; Verspaij GJ; Rosbergen S; IMP; NMD

    2003-01-01

    Met behulp van het rapport kunnen ontwikkelaars, beheerders en betrokken managers bij ICT projecten meer inzicht krijgen in de .NET technologie en een goede keuze maken in de inzetbaarheid van deze technologie. Het rapport geeft de bevindingen en conclusies van een verkennende studie naar het

  2. Complexity Metrics for Workflow Nets

    DEFF Research Database (Denmark)

    Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.

    2009-01-01

    Process modeling languages such as EPCs, BPMN, flow charts, UML activity diagrams, Petri nets, etc.\\ are used to model business processes and to configure process-aware information systems. It is known that users have problems understanding these diagrams. In fact, even process engineers and system...

  3. Communicating with the Net Generation

    Science.gov (United States)

    2011-03-11

    resource investment is necessary to sustain a high quality all-volunteer force. 9 Leadership Technique for the Net Generation Army Regulation 600...Generations at Work, Millenials at Work, http://www.generationsatwork. com /articles_millennials_at_work.php (accessed November 21, 2010). 31 Thomas

  4. Net Neutrality in the Netherlands

    NARCIS (Netherlands)

    van Eijk, N.

    2014-01-01

    The Netherlands is among the first countries that have put specific net neutrality standards in place. The decision to implement specific regulation was influenced by at least three factors. The first was the prevailing social and academic debate, partly due to developments in the United States. The

  5. Surgery for GEP-NETs

    DEFF Research Database (Denmark)

    Knigge, Ulrich; Hansen, Carsten Palnæs

    2012-01-01

    Surgery is the only treatment that may cure the patient with gastroentero-pancreatic (GEP) neuroendocrine tumours (NET) and neuroendocrine carcinomas (NEC) and should always be considered as first line treatment if R0/R1 resection can be achieved. The surgical and interventional procedures for GEP...

  6. Net4Care PHMR Tutorial

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    Goal To demonstrate how to use the Net4Care PHMR builder module to a) Create a SimpleClinicalDocument instance and populate it with relevant administrative and medical information to form a tele medical report of a set of measurements, b) Use the provided DanishPHMRBuilder to generate a correctly...

  7. Yeast identification: reassessment of assimilation tests as sole universal identifiers.

    Science.gov (United States)

    Spencer, J; Rawling, S; Stratford, M; Steels, H; Novodvorska, M; Archer, D B; Chandra, S

    2011-11-01

    To assess whether assimilation tests in isolation remain a valid method of identification of yeasts, when applied to a wide range of environmental and spoilage isolates. Seventy-one yeast strains were isolated from a soft drinks factory. These were identified using assimilation tests and by D1/D2 rDNA sequencing. When compared to sequencing, assimilation test identifications (MicroLog™) were 18·3% correct, a further 14·1% correct within the genus and 67·6% were incorrectly identified. The majority of the latter could be attributed to the rise in newly reported yeast species. Assimilation tests alone are unreliable as a universal means of yeast identification, because of numerous new species, variability of strains and increasing coincidence of assimilation profiles. Assimilation tests still have a useful role in the identification of common species, such as the majority of clinical isolates. It is probable, based on these results, that many yeast identifications reported in older literature are incorrect. This emphasizes the crucial need for accurate identification in present and future publications. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  8. IASI Radiance Data Assimilation in Local Ensemble Transform Kalman Filter

    Science.gov (United States)

    Cho, K.; Hyoung-Wook, C.; Jo, Y.

    2016-12-01

    Korea institute of Atmospheric Prediction Systems (KIAPS) is developing NWP model with data assimilation systems. Local Ensemble Transform Kalman Filter (LETKF) system, one of the data assimilation systems, has been developed for KIAPS Integrated Model (KIM) based on cubed-sphere grid and has successfully assimilated real data. LETKF data assimilation system has been extended to 4D- LETKF which considers time-evolving error covariance within assimilation window and IASI radiance data assimilation using KPOP (KIAPS package for observation processing) with RTTOV (Radiative Transfer for TOVS). The LETKF system is implementing semi operational prediction including conventional (sonde, aircraft) observation and AMSU-A (Advanced Microwave Sounding Unit-A) radiance data from April. Recently, the semi operational prediction system updated radiance observations including GPS-RO, AMV, IASI (Infrared Atmospheric Sounding Interferometer) data at July. A set of simulation of KIM with ne30np4 and 50 vertical levels (of top 0.3hPa) were carried out for short range forecast (10days) within semi operation prediction LETKF system with ensemble forecast 50 members. In order to only IASI impact, our experiments used only conventional and IAIS radiance data to same semi operational prediction set. We carried out sensitivity test for IAIS thinning method (3D and 4D). IASI observation number was increased by temporal (4D) thinning and the improvement of IASI radiance data impact on the forecast skill of model will expect.

  9. Cholesterol Assimilation by Lactobacillus Probiotic Bacteria: An In Vitro Investigation

    Directory of Open Access Journals (Sweden)

    Catherine Tomaro-Duchesneau

    2014-01-01

    Full Text Available Excess cholesterol is associated with cardiovascular diseases (CVD, an important cause of mortality worldwide. Current CVD therapeutic measures, lifestyle and dietary interventions, and pharmaceutical agents for regulating cholesterol levels are inadequate. Probiotic bacteria have demonstrated potential to lower cholesterol levels by different mechanisms, including bile salt hydrolase activity, production of compounds that inhibit enzymes such as 3-hydroxy-3-methylglutaryl coenzyme A, and cholesterol assimilation. This work investigates 11 Lactobacillus strains for cholesterol assimilation. Probiotic strains for investigation were selected from the literature: Lactobacillus reuteri NCIMB 11951, L. reuteri NCIMB 701359, L. reuteri NCIMB 702655, L. reuteri NCIMB 701089, L. reuteri NCIMB 702656, Lactobacillus fermentum NCIMB 5221, L. fermentum NCIMB 8829, L. fermentum NCIMB 2797, Lactobacillus rhamnosus ATCC 53103 GG, Lactobacillus acidophilus ATCC 314, and Lactobacillus plantarum ATCC 14917. Cholesterol assimilation was investigated in culture media and under simulated intestinal conditions. The best cholesterol assimilator was L. plantarum ATCC 14917 (15.18 ± 0.55 mg/1010 cfu in MRS broth. L. reuteri NCIMB 701089 assimilated over 67% (2254.70 ± 63.33 mg/1010 cfu of cholesterol, the most of all the strains, under intestinal conditions. This work demonstrates that probiotic bacteria can assimilate cholesterol under intestinal conditions, with L. reuteri NCIMB 701089 showing great potential as a CVD therapeutic.

  10. Business Profile of Boat Lift Net and Stationary Lift Net Fishing Gear in Morodemak Waters Central Java

    Science.gov (United States)

    Hapsari, Trisnani D.; Jayanto, Bogi B.; Fitri, Aristi D. P.; Triarso, I.

    2018-02-01

    Lift net is one of the fishing gears that is used widely in the Morodemak coastal fishing port (PPP) for catching pelagic fish. The yield of fish captured by these fishing gear has high economic value, such as fish belt (Trichiurus sp), squids (Loligo sp) and anchovies (Stelophorus sp). The aims of this research were to determine the technical aspects of boat lift net and stationary lift net fishing gear in Morodemak Waters Demak Regency; to find out the financial aspect of those fishing gears and to analyze the financial feasibility by counting PP, NPV, IRR, and B/C ratio criteria. This research used case study method with descriptive analysis. The sampling method was purposive sampling with 22 fishermen as respondents. The result of the research showed that the average of boat lift net acceptance was Rp 388,580,000. The financial analysis of fisheries boat lift net with the result of NPV Rp 836,149,272, PP 2.44 years, IRR value 54%, and B/C ratio 1.73. The average of stationary lift net acceptance was Rp 27,750,000. The financial analysis lift net with the result of NPV Rp 37,937,601; PP 1.96 years, IRR value 86%, and B/C ratio 1.32. This research had a positive NPV value, B/C ratio >1, and IRR > discount rate (12 %). This study concluded that the fishery business of boat lift net and stationary lift net in Morodemak coastal fishing port (PPP) was worth running.

  11. Exploring synchronisation in nonlinear data assimilation

    Science.gov (United States)

    Rodrigues-Pinheiro, Flavia; van Leeuwen, Peter Jan

    2016-04-01

    Present-day data assimilation methods are based on linearizations and face serious problems in strongly nonlinear cases such as convection. A promising solution to this problem is a particle filter, which provides a representation of the model probability density function (pdf) by a discrete set of model states, or particles. The basic particle filter uses Bayes's theorem directly, but does not work in high-dimensional cases. The performance can be improved by considering the proposal density freedom. This allows one to change the model equations to bring the particles closer to the observations, resulting in very efficient update schemes at observation times, but extending these schemes between observation times is computationally expensive. Simple solutions like nudging have been shown to be not powerful enough. A potential solution might be synchronization, in which one tries to synchronise the model of a system with the true evolution of the system via the observations. In practice this means that an extra term is added to the model equations that hampers growth of instabilities on the synchronization manifold. Especially the delayed versions, where observations are allowed to influence the state in the past have shown some remarkable successes. Unfortunately, all efforts ignore errors in the observations, and as soon as these are introduced the performance degrades considerably. There is a close connection between time-delayed synchronization and a Kalman Smoother, which does allow for observational (and other) errors. In this presentation we will explore this connection to the full, with a view to extend synchronization to more realistic settings. Specifically performance of the spread of information from observed to unobserved variables is studied in detail. The results indicate that this extended synchronisation is a promising tool to steer the model states towards the observations efficiently. If time permits, we will show initial results of embedding the

  12. .net

    Directory of Open Access Journals (Sweden)

    Le Comité de Rédaction d' EspacesTemps.net

    2002-06-01

    Full Text Available EspacesTemps lance aujourd'hui deux objets différents : un site internet et, sur ce site, Le Journal . Il s'agit donc de bien plus, et, au fond, de tout autre chose qu'un simple outil de communication destiné à informer nos lecteurs de nos parutions. Ce n'est pas non plus la « mise en ligne » de nos numéros-papier. L'internet nous donne au contraire l'occasion de réaliser, dans de meilleures conditions, ce que nous avons tenté de faire depuis quelques ...

  13. Caught in the Net: Perineuronal Nets and Addiction

    Directory of Open Access Journals (Sweden)

    Megan Slaker

    2016-01-01

    Full Text Available Exposure to drugs of abuse induces plasticity in the brain and creates persistent drug-related memories. These changes in plasticity and persistent drug memories are believed to produce aberrant motivation and reinforcement contributing to addiction. Most studies have explored the effect drugs of abuse have on pre- and postsynaptic cells and astrocytes; however, more recently, attention has shifted to explore the effect these drugs have on the extracellular matrix (ECM. Within the ECM are unique structures arranged in a net-like manner, surrounding a subset of neurons called perineuronal nets (PNNs. This review focuses on drug-induced changes in PNNs, the molecules that regulate PNNs, and the expression of PNNs within brain circuitry mediating motivation, reward, and reinforcement as it pertains to addiction.

  14. Army Net Zero Prove Out. Net Zero Energy Best Practices

    Science.gov (United States)

    2014-11-18

    recovery and cogeneration opportunities, offsetting the remaining demand with the production of renewable energy from onsite sources so that the Net...implementing energy recovery and cogeneration opportunities, and then offsetting the remaining demand with the production of renewable energy from on-site...they impact overall energy performance. The use of energy modeling in the design stage provides insights that can contribute to more effective design

  15. Net alkalinity and net acidity 2: Practical considerations

    Science.gov (United States)

    Kirby, C.S.; Cravotta, C.A.

    2005-01-01

    The pH, alkalinity, and acidity of mine drainage and associated waters can be misinterpreted because of the chemical instability of samples and possible misunderstandings of standard analytical method results. Synthetic and field samples of mine drainage having various initial pH values and concentrations of dissolved metals and alkalinity were titrated by several methods, and the results were compared to alkalinity and acidity calculated based on dissolved solutes. The pH, alkalinity, and acidity were compared between fresh, unoxidized and aged, oxidized samples. Data for Pennsylvania coal mine drainage indicates that the pH of fresh samples was predominantly acidic (pH 2.5-4) or near neutral (pH 6-7); ??? 25% of the samples had pH values between 5 and 6. Following oxidation, no samples had pH values between 5 and 6. The Standard Method Alkalinity titration is constrained to yield values >0. Most calculated and measured alkalinities for samples with positive alkalinities were in close agreement. However, for low-pH samples, the calculated alkalinity can be negative due to negative contributions by dissolved metals that may oxidize and hydrolyze. The Standard Method hot peroxide treatment titration for acidity determination (Hot Acidity) accurately indicates the potential for pH to decrease to acidic values after complete degassing of CO2 and oxidation of Fe and Mn, and it indicates either the excess alkalinity or that required for neutralization of the sample. The Hot Acidity directly measures net acidity (= -net alkalinity). Samples that had near-neutral pH after oxidation had negative Hot Acidity; samples that had pH mine drainage treatment can lead to systems with insufficient Alkalinity to neutralize metal and H+ acidity and is not recommended. The use of net alkalinity = -Hot Acidity titration is recommended for the planning of mine drainage treatment. The use of net alkalinity = (Alkalinitymeasured - Aciditycalculated) is recommended with some cautions

  16. CLIMATIC FORECASTING OF NET INFILTRATION AT YUCCA MOUNTAIN, USING ANALOGUE METEOROLOGICAL DATA

    International Nuclear Information System (INIS)

    B. Faybishenko

    2005-01-01

    Net infiltration is a key hydrologic parameter that controls the rate of deep percolation through the unsaturated zone, the groundwater recharge, radionuclide transport, and seepage into the underground tunnels. Because net infiltration is largely affected by climatic conditions, future changes in climatic conditions will potentially alter net infiltration. The objectives of this presentation are to: (1) Present a conceptual model and a semi-empirical approach for regional, climatic forecasting of net infiltration, based on the precipitation and temperature data from analogue meteorological stations, and (2) Demonstrate the results of forecasting net infiltration for future climates--interglacial, monsoon and glacial--over the Yucca Mountain region for the period of 500,000 years. Calculations of the net infiltration were performed using a modified Budyko's water-balance model, for which potential evapotranspiration was evaluated from the temperature-based Thornthwaite formula. (Both Budyko's and Thornthwaite's formulae have been used broadly in hydrological studies.) The results of calculations were used for ranking net infiltration, along with the aridity and precipitation-effectiveness (P-E) indexes, for future climatic scenarios. Using this approach, we determined a general trend of increasing net infiltration from the present-day (interglacial) climate to monsoon, intermediate (glacial transition), and then to the glacial climate. Ranking of the aridity and P-E indexes is practically the same as that of net infiltration. The validation of the computed net infiltration rates yielded a good match with other field and modeling study results of groundwater recharge and net infiltration evaluation

  17. AMOC variations in 1979-2008 simulated by NCEP operational ocean data assimilation system

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Boyin [Climate Prediction Center, NOAA, Camp Springs, MD (United States); National Climate Data Center, Asheville, NC (United States); Xue, Yan; Kumar, Arun [Climate Prediction Center, NOAA, Camp Springs, MD (United States); Behringer, David W. [Environmental Modeling Center, NOAA, Camp Springs, MD (United States)

    2012-02-15

    Variations in the Atlantic meridional overturning circulation (AMOC) between 1979 and 2008 are documented using the operational ocean analysis, the Global Ocean Data Assimilation System (GODAS), at the National Centers for Climate Prediction (NCEP). The maximum AMOC at 40 N is about 16 Sv in average with peak-to-peak variability of 3-4 Sv. The AMOC variations are dominated by an upward trend from 1980 to 1995, and a downward trend from 1995 to 2008. The maximum AMOC at 26.5 N is slightly weaker than hydrographic estimates and observations from mooring array. The dominant variability of the AMOC in 20 -65 N (the first EOF, 51% variance) is highly correlated with that in the subsurface temperature (the first EOF, 33% variance), and therefore, with density (the first EOF, 25% variance) in the North Atlantic, and is consistent with the observational estimates based on the World Ocean Database 2005. The dominant variabilities of AMOC and subsurface temperature are also analyzed in the context of possible links with the net surface heat flux, deep convection, western boundary current, and subpolar gyre. Variation in the net surface heat flux is further linked to the North Atlantic Oscillation (NAO) index which is found to lead AMOC variations by about 5 years. Our results indicate that AMOC variations can be documented based on an ocean analysis system such as GODAS. (orig.)

  18. A land data assimilation system for sub-Saharan Africa food and water security applications.

    Science.gov (United States)

    McNally, Amy; Arsenault, Kristi; Kumar, Sujay; Shukla, Shraddhanand; Peterson, Pete; Wang, Shugong; Funk, Chris; Peters-Lidard, Christa D; Verdin, James P

    2017-02-14

    Seasonal agricultural drought monitoring systems, which rely on satellite remote sensing and land surface models (LSMs), are important for disaster risk reduction and famine early warning. These systems require the best available weather inputs, as well as a long-term historical record to contextualize current observations. This article introduces the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS), a custom instance of the NASA Land Information System (LIS) framework. The FLDAS is routinely used to produce multi-model and multi-forcing estimates of hydro-climate states and fluxes over semi-arid, food insecure regions of Africa. These modeled data and derived products, like soil moisture percentiles and water availability, were designed and are currently used to complement FEWS NET's operational remotely sensed rainfall, evapotranspiration, and vegetation observations. The 30+ years of monthly outputs from the FLDAS simulations are publicly available from the NASA Goddard Earth Science Data and Information Services Center (GES DISC) and recommended for use in hydroclimate studies, early warning applications, and by agro-meteorological scientists in Eastern, Southern, and Western Africa.

  19. Net alkalinity and net acidity 1: Theoretical considerations

    International Nuclear Information System (INIS)

    Kirby, Carl S.; Cravotta, Charles A.

    2005-01-01

    Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO 2 , and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation problems. Theoretically defined 'CO 2 -acidity' is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO 2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass-action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mgL -1 as CaCO 3 (based on pH and analytical concentrations of dissolved Fe II , Fe III , Mn, and Al in mgL -1 ):acidity calculated =50{1000(10 -pH )+[2(Fe II )+3(Fe III )]/56+2(Mn) /55+3(Al)/27}underestimates contributions from HSO 4 - and H + , but overestimates the acidity due to Fe 3+ and Al 3+ . However, these errors tend to approximately cancel each other. It is demonstrated that 'net alkalinity' is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the

  20. Net alkalinity and net acidity 1: Theoretical considerations

    Science.gov (United States)

    Kirby, C.S.; Cravotta, C.A.

    2005-01-01

    Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation problems. Theoretically defined "CO 2-acidity" is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass- action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mg L -1 as CaCO3 (based on pH and analytical concentrations of dissolved FeII, FeIII, Mn, and Al in mg L -1):aciditycalculated=50{1000(10-pH)+[2(FeII)+3(FeIII)]/56+2(Mn)/ 55+3(Al)/27}underestimates contributions from HSO4- and H+, but overestimates the acidity due to Fe3+ and Al3+. However, these errors tend to approximately cancel each other. It is demonstrated that "net alkalinity" is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation, (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the value obtained in a

  1. Data Assimilation in Forest Inventory: First Empirical Results

    Directory of Open Access Journals (Sweden)

    Mattias Nyström

    2015-12-01

    Full Text Available Data assimilation techniques were used to estimate forest stand data in 2011 by sequentially combining remote sensing based estimates of forest variables with predictions from growth models. Estimates of stand data, based on canopy height models obtained from image matching of digital aerial images at six different time-points between 2003 and 2011, served as input to the data assimilation. The assimilation routines were built on the extended Kalman filter. The study was conducted in hemi-boreal forest at the Remningstorp test site in southern Sweden (lat. 13°37′ N; long. 58°28′ E. The assimilation results were compared with two other methods used in practice for estimation of forest variables: the first was to use only the most recent estimate obtained from remotely sensed data (2011 and the second was to forecast the first estimate (2003 to the endpoint (2011. All three approaches were validated using nine 40 m radius validation plots, which were carefully measured in the field. The results showed that the data assimilation approach provided better results than the two alternative methods. Data assimilation of remote sensing time series has been used previously for calibrating forest ecosystem models, but, to our knowledge, this is the first study with real data where data assimilation has been used for estimating forest inventory data. The study constitutes a starting point for the development of a framework useful for sequentially utilizing all types of remote sensing data in order to provide precise and up-to-date estimates of forest stand parameters.

  2. Assimilation of 15N-labelled urea nitrogen and ammonium nitrate nitrogen by plants in case of root and non-root fertilization

    International Nuclear Information System (INIS)

    Muravin, Eh.A.; Kozhemyachko, V.A.; Vernichenko, I.V.

    1974-01-01

    Assimilation of 15 N labeled urea and ammonium nitrate in root and foliar application by spring wheat and barley has been studied during 1970-1973 period in a series of vegetative experiments at the Department of Agrochemistry, Timiryazev Agricultural Academy, and at D.N. Pryanishnikov Experimental Agrochemical Station. Additional fertilizer nitrogen applied at later ontogenesis stages (flowering and milky ripeness) is utilized mostly for protein synthesis in developing grains, thus leading to a significant increase in the relative grain protein content. A transfer of a part of nitrogen from the main ortion of fertilizer at later stages of nitrition results, at the same time, in a lower yield. Nitrogen utilization degree of urea and ammonium nitrate, when introduced before sowing or at the flowering stage is similar but in the latter case, however, additional assimilation of soil nitrogen is lower. The assimilation rate of nitrogen in root application is the lower the later the fertilizer is applied. When ammonium nitrate is additionally applied as nutrition to barley at the milky ripeness stage, ammonia and nitrate nitrogen are assimilated at the same rate and to the same extent but ammonia nitrogen is more rapidly used for protein synthesis and the rate of its transfer to the developing grains is higher. The rate of nitrogen assimilation at plant is much higher in foliar than in root application. Wheat utilizes more urea nitrogen at the flowering stage when root application is used but at the milky ripeness stage foliar application is more effective

  3. Assimilation of /sup 15/N-labelled urea nitrogen and ammonium nitrate nitrogen by plants in case of root and non-root fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Muravin, E A; Kozhemyachko, V A; Vernichenko, I V

    1974-01-01

    Assimilation of /sup 15/N labeled urea and ammonium nitrate in root and foliar application by spring wheat and barley has been studied during 1970-1973 period in a series of vegetative experiments at the Department of Agrochemistry, Timiryazev Agricultural Academy, and at D.N. Pryanishnikov Experimental Agrochemical Station. Additional fertilizer nitrogen applied at later ontogenesis stages (flowering and milky ripeness) is utilized mostly for protein synthesis in developing grains, thus leading to a significant increase in the relative grain protein content. A transfer of a part of nitrogen from the main portion of fertilizer at later stages of nitrition results, at the same time, in a lower yield. Nitrogen utilization degree of urea and ammonium nitrate, when introduced before sowing or at the flowering stage is similar but in the latter case, however, additional assimilation of soil nitrogen is lower. The assimilation rate of nitrogen in root application is the lower the later the fertilizer is applied. When ammonium nitrate is additionally applied as nutrition to barley at the milky ripeness stage, ammonia and nitrate nitrogen are assimilated at the same rate and to the same extent but ammonia nitrogen is more rapidly used for protein synthesis and the rate of its transfer to the developing grains is higher. The rate of nitrogen assimilation at plant is much higher in foliar than in root application. Wheat utilizes more urea nitrogen at the flowering stage when root application is used but at the milky ripeness stage foliar application is more effective.

  4. Les dispositifs du Net art

    OpenAIRE

    Fourmentraux, Jean-Paul

    2010-01-01

    La pratique du Net art radicalise la question du potentiel communicationnel d’un média —Internet— qui constitue tout à la fois le support technique, l’outil créatif et le dispositif social de l’œuvre. Les technologies de l’information et de la communication (TIC) placent en effet l’œuvre d’art au cœur d’une négociation socialement distribuée entre l’artiste et le public. L’article est focalisé sur cette construction collective du Net art et sur ses mises en scènes. Il montre le travail artist...

  5. Complexity Metrics for Workflow Nets

    DEFF Research Database (Denmark)

    Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.

    2009-01-01

    analysts have difficulties grasping the dynamics implied by a process model. Recent empirical studies show that people make numerous errors when modeling complex business processes, e.g., about 20 percent of the EPCs in the SAP reference model have design flaws resulting in potential deadlocks, livelocks......, etc. It seems obvious that the complexity of the model contributes to design errors and a lack of understanding. It is not easy to measure complexity, however. This paper presents three complexity metrics that have been implemented in the process analysis tool ProM. The metrics are defined...... for a subclass of Petri nets named Workflow nets, but the results can easily be applied to other languages. To demonstrate the applicability of these metrics, we have applied our approach and tool to 262 relatively complex Protos models made in the context of various student projects. This allows us to validate...

  6. High bicarbonate assimilation in the dark by Arctic bacteria.

    Science.gov (United States)

    Alonso-Sáez, Laura; Galand, Pierre E; Casamayor, Emilio O; Pedrós-Alió, Carlos; Bertilsson, Stefan

    2010-12-01

    Although both autotrophic and heterotrophic microorganisms incorporate CO₂ in the dark through different metabolic pathways, this process has usually been disregarded in oxic marine environments. We studied the significance and mediators of dark bicarbonate assimilation in dilution cultures inoculated with winter Arctic seawater. At stationary phase, bicarbonate incorporation rates were high (0.5-2.5 μg C L⁻¹ d⁻¹) and correlated with rates of bacterial heterotrophic production, suggesting that most of the incorporation was due to heterotrophs. Accordingly, very few typically chemoautotrophic bacteria were detected by 16S rRNA gene cloning. The genetic analysis of the biotin carboxylase gene accC putatively involved in archaeal CO₂ fixation did not yield any archaeal sequence, but amplified a variety of bacterial carboxylases involved in fatty acids biosynthesis, anaplerotic pathways and leucine catabolism. Gammaproteobacteria dominated the seawater cultures (40-70% of cell counts), followed by Betaproteobacteria and Flavobacteria as shown by catalyzed reporter deposition fluorescence in situ hybridization (CARDFISH). Both Beta- and Gammaproteobacteria were active in leucine and bicarbonate uptake, while Flavobacteria did not take up bicarbonate, as measured by microautoradiography combined with CARDFISH. Within Gammaproteobacteria, Pseudoalteromonas-Colwellia and Oleispira were very active in bicarbonate uptake (ca. 30 and 70% of active cells, respectively), while the group Arctic96B-16 did not take up bicarbonate. Our results suggest that, potentially, the incorporation of CO₂ can be relevant for the metabolism of specific Arctic heterotrophic phylotypes, promoting the maintenance of their cell activity and/or longer survival under resource depleted conditions.

  7. Photosynthetic characteristics and distribution of 14C assimilates in the winter wheat of late growing period in dry land

    International Nuclear Information System (INIS)

    Qing Huimin; Yu Guohua; Yin Xisheng; Zhan Shumin; Liu Xin

    1999-01-01

    The photosynthetic characteristics and distribution of 14 C assimilates of winter wheat in late growing period in the field of natural drought condition was studied. The results showed that photosynthetic rate of flag leaves was up to 14.24 μmol CO 2 ·m -2 ·s -1 , the ribulose-1,5-bisphosphate carboxylase (RUBpCase) activity of flag leaves in late growing period in field drought treatment was about 20∼23 μmol CO 2 ·min -1 ·g -1 dw when the water potential of flag leaves was about -1.8∼-2.1 MPa. The photosynthetic rate of flag leaves of control was 15.15 μmol CO 2 ·m -2 ·s -1 . The RUBpCase activity was about 22∼25 μmol CO 2 ·min -1 · -1 ·g -1 dw in the field of irrigated condition when the water potential of flag leaves was about -1.65∼-1.8 MPa, indicating that the RUBpCase activity of flag leaves in drought condition was not a major limiting factor. The total distribution rate of 14 C assimilates of flag leaves, flag leaf sheath, flag leaf node and awn to grain in drought treatment was about 44.8%, and that of control was about 40.2%. The results also showed that in late growing period the proportion of 14 C assimilates to roots in the both drought and control treatment was similar, about 2.0%. But the amount of 14 C assimilates in the roots in the soil layer of 120∼200 cm was up to 8.34% of the total 14 C assimilates in the roots, however, that of control was only about 3.6%

  8. dotNet som multimediaplattform

    OpenAIRE

    Johansson, Glenn

    2008-01-01

    As the speed and complexity of computers have increased so have software and the expectations of users. Software development follows a straightforward evolution where complicated tasks are made easier by better tools; this repeats itself as those tasks in turn are automated. Software mechanics that were seen as revolutionary a decade ago are seen as obvious requirements that no multimedia application can be without. dotNet is the next step in line and makes it easier and faster to build softw...

  9. Assimilation of GRACE Terrestrial Water Storage into a Land Surface Model: Evaluation 1 and Potential Value for Drought Monitoring in Western and Central Europe

    Science.gov (United States)

    Li, Bailing; Rodell, Matthew; Zaitchik, Benjamin F.; Reichle, Rolf H.; Koster, Randal D.; van Dam, Tonie M.

    2012-01-01

    A land surface model s ability to simulate states (e.g., soil moisture) and fluxes (e.g., runoff) is limited by uncertainties in meteorological forcing and parameter inputs as well as inadequacies in model physics. In this study, anomalies of terrestrial water storage (TWS) observed by the Gravity Recovery and Climate Experiment (GRACE) satellite mission were assimilated into the NASA Catchment land surface model in western and central Europe for a 7-year period, using a previously developed ensemble Kalman smoother. GRACE data assimilation led to improved runoff correlations with gauge data in 17 out of 18 hydrological basins, even in basins smaller than the effective resolution of GRACE. Improvements in root zone soil moisture were less conclusive, partly due to the shortness of the in situ data record. In addition to improving temporal correlations, GRACE data assimilation also reduced increasing trends in simulated monthly TWS and runoff associated with increasing rates of precipitation. GRACE assimilated root zone soil moisture and TWS fields exhibited significant changes in their dryness rankings relative to those without data assimilation, suggesting that GRACE data assimilation could have a substantial impact on drought monitoring. Signals of drought in GRACE TWS correlated well with MODIS Normalized Difference Vegetation Index (NDVI) data in most areas. Although they detected the same droughts during warm seasons, drought signatures in GRACE derived TWS exhibited greater persistence than those in NDVI throughout all seasons, in part due to limitations associated with the seasonality of vegetation.

  10. NET model coil test possibilities

    International Nuclear Information System (INIS)

    Erb, J.; Gruenhagen, A.; Herz, W.; Jentzsch, K.; Komarek, P.; Lotz, E.; Malang, S.; Maurer, W.; Noether, G.; Ulbricht, A.; Vogt, A.; Zahn, G.; Horvath, I.; Kwasnitza, K.; Marinucci, C.; Pasztor, G.; Sborchia, C.; Weymuth, P.; Peters, A.; Roeterdink, A.

    1987-11-01

    A single full size coil for NET/INTOR represents an investment of the order of 40 MUC (Million Unit Costs). Before such an amount of money or even more for the 16 TF coils is invested as much risks as possible must be eliminated by a comprehensive development programme. In the course of such a programme a coil technology verification test should finally prove the feasibility of NET/INTOR TF coils. This study report is almost exclusively dealing with such a verification test by model coil testing. These coils will be built out of two Nb 3 Sn-conductors based on two concepts already under development and investigation. Two possible coil arrangements are discussed: A cluster facility, where two model coils out of the two Nb 3 TF-conductors are used, and the already tested LCT-coils producing a background field. A solenoid arrangement, where in addition to the two TF model coils another model coil out of a PF-conductor for the central PF-coils of NET/INTOR is used instead of LCT background coils. Technical advantages and disadvantages are worked out in order to compare and judge both facilities. Costs estimates and the time schedules broaden the base for a decision about the realisation of such a facility. (orig.) [de

  11. NET-2 Network Analysis Program

    International Nuclear Information System (INIS)

    Malmberg, A.F.

    1974-01-01

    The NET-2 Network Analysis Program is a general purpose digital computer program which solves the nonlinear time domain response and the linearized small signal frequency domain response of an arbitrary network of interconnected components. NET-2 is capable of handling a variety of components and has been applied to problems in several engineering fields, including electronic circuit design and analysis, missile flight simulation, control systems, heat flow, fluid flow, mechanical systems, structural dynamics, digital logic, communications network design, solid state device physics, fluidic systems, and nuclear vulnerability due to blast, thermal, gamma radiation, neutron damage, and EMP effects. Network components may be selected from a repertoire of built-in models or they may be constructed by the user through appropriate combinations of mathematical, empirical, and topological functions. Higher-level components may be defined by subnetworks composed of any combination of user-defined components and built-in models. The program provides a modeling capability to represent and intermix system components on many levels, e.g., from hole and electron spatial charge distributions in solid state devices through discrete and integrated electronic components to functional system blocks. NET-2 is capable of simultaneous computation in both the time and frequency domain, and has statistical and optimization capability. Network topology may be controlled as a function of the network solution. (U.S.)

  12. Assimilation approach to measuring organizational change from pre- to post-intervention.

    Science.gov (United States)

    Moore, Scott C; Osatuke, Katerine; Howe, Steven R

    2014-03-22

    To present a conceptual and measurement strategy that allows to objectively, sensitively evaluate intervention progress based on data of participants' perceptions of presenting problems. We used as an example an organization development intervention at a United States Veterans Affairs medical center. Within a year, the intervention addressed the hospital's initially serious problems and multiple stakeholders (employees, management, union representatives) reported satisfaction with progress made. Traditional quantitative outcome measures, however, failed to capture the strong positive impact consistently reported by several types of stakeholders in qualitative interviews. To address the paradox, full interview data describing the medical center pre- and post- intervention were examined applying a validated theoretical framework from another discipline: Psychotherapy research. The Assimilation model is a clinical-developmental theory that describes empirically grounded change levels in problematic experiences, e.g., problems reported by participants. The model, measure Assimilation of Problematic Experiences Scale (APES), and rating procedure have been previously applied across various populations and problem types, mainly in clinical but also in non-clinical settings. We applied the APES to the transcribed qualitative data of intervention participants' interviews, using the method closely replicating prior assimilation research (the process whereby trained clinicians familiar with the Assimilation model work with full, transcribed interview data to assign the APES ratings). The APES ratings summarized levels of progress which was defined as participants' assimilation level of problematic experiences, and compared from pre- to post-intervention. The results were consistent with participants' own reported perceptions of the intervention impact. Increase in APES levels from pre- to post-intervention suggested improvement, missed in the previous quantitative measures

  13. DART: New Research Using Ensemble Data Assimilation in Geophysical Models

    Science.gov (United States)

    Hoar, T. J.; Raeder, K.

    2015-12-01

    The Data Assimilation Research Testbed (DART) is a community facilityfor ensemble data assimilation developed and supported by the NationalCenter for Atmospheric Research. DART provides a comprehensive suite of software, documentation, and tutorials that can be used for ensemble data assimilation research, operations, and education. Scientists and software engineers at NCAR are available to support DART users who want to use existing DART products or develop their own applications. Current DART users range from university professors teaching data assimilation, to individual graduate students working with simple models, through national laboratories doing operational prediction with large state-of-the-art models. DART runs efficiently on many computational platforms ranging from laptops through thousands of cores on the newest supercomputers.This poster focuses on several recent research activities using DART with geophysical models.Using CAM/DART to understand whether OCO-2 Total Precipitable Water observations can be useful in numerical weather prediction.Impacts of the synergistic use of Infra-red CO retrievals (MOPITT, IASI) in CAM-CHEM/DART assimilations.Assimilation and Analysis of Observations of Amazonian Biomass Burning Emissions by MOPITT (aerosol optical depth), MODIS (carbon monoxide) and MISR (plume height).Long term evaluation of the chemical response of MOPITT-CO assimilation in CAM-CHEM/DART OSSEs for satellite planning and emission inversion capabilities.Improved forward observation operators for land models that have multiple land use/land cover segments in a single grid cell,Simulating mesoscale convective systems (MCSs) using a variable resolution, unstructured grid in the Model for Prediction Across Scales (MPAS) and DART.The mesoscale WRF+DART system generated an ensemble of year-long, real-time initializations of a convection allowing model over the United States.Constraining WACCM with observations in the tropical band (30S-30N) using DART

  14. Exploring the Potential use of Photo-Selective Nets for Fruit Growth Regulation in Apple Explorando el uso Potencial de Mallas Foto-Selectivas para la Regulación del Crecimiento de Fruto en Manzano

    Directory of Open Access Journals (Sweden)

    Richard M Bastías

    2012-06-01

    Full Text Available The effect of shading (i.e. reduction of sunlight availability on fruit growth physiology has been widely studied in apple (Malus domestica Borkh., but little knowledge exist about fruit growth responses to changes in the light spectrum. The aim of the present research was to study the effect of use of colored nets with differential sunlight transmission in the blue (B, 400-500 nm, red (R, 600-700 nm and far-red (FR, 700-800 nm spectra on apple fruit growth and physiological associated responses. Three year old 'Fuji' apple trees were covered with 40% photo-selective blue and red shade nets, 40% neutral grey shade net, and 20% neutral white net as control. Red and blue net reduced in the same proportion (27% the photosynthetically active radiation with respect to control. However, blue net increased by 30% and reduced by 10% the B:R and R:FR the light relations, respectively. Maximal fruit growth rate under blue and grey nets was 15-20% greater than control. Fruit weight under blue net was 17% greater than control, but no significant differences in fruit weight were found among red net and control. Leaf photosynthesis and total leaf area under blue net were 28% and 30% higher than control, respectively; with ensuing positive effect on tree net C assimilation rate and total dry matter production. Results suggest that shifting the B, R, and FR light composition with photo-selective nets could be a useful tool to manipulate the photosynthetic and morphogenetic process regulating the carbohydrate availability for apple fruit growth.El efecto del sombreado (i.e. reducción de la cantidad de luz solar sobre la fisiología de crecimiento de fruto ha sido ampliamente estudiado en manzano (Malus domestica Borkh., pero existe poco conocimiento sobre respuestas de crecimiento del fruto a cambios en el espectro de la luz. El objetivo de la presente investigación fue estudiar el efecto del uso de mallas de color con transmisión diferencial de la luz en el

  15. Assimilation of Altimeter Data into a Quasigeostrophic Model of the Gulf Stream System. Part 2; Assimilation Results

    Science.gov (United States)

    Capotondi, Antonietta; Holland, William R.; Malanotte-Rizzoli, Paola

    1995-01-01

    The improvement in the climatological behavior of a numerical model as a consequence of the assimilation of surface data is investigated. The model used for this study is a quasigeostrophic (QG) model of the Gulf Stream region. The data that have been assimilated are maps of sea surface height that have been obtained as the superposition of sea surface height variability deduced from the Geosat altimeter measurements and a mean field constructed from historical hydrographic data. The method used for assimilating the data is the nudging technique. Nudging has been implemented in such a way as to achieve a high degree of convergence of the surface model fields toward the observations. Comparisons of the assimilation results with available in situ observations show a significant improvement in the degree of realism of the climatological model behavior, with respect to the model in which no data are assimilated. The remaining discrepancies in the model mean circulation seem to be mainly associated with deficiencies in the mean component of the surface data that are assimilated. On the other hand, the possibility of building into the model more realistic eddy characteristics through the assimilation of the surface eddy field proves very successful in driving components of the mean model circulation that are in relatively good agreement with the available observations. Comparisons with current meter time series during a time period partially overlapping the Geosat mission show that the model is able to 'correctly' extrapolate the instantaneous surface eddy signals to depths of approximately 1500 m. The correlation coefficient between current meter and model time series varies from values close to 0.7 in the top 1500 m to values as low as 0.1-0.2 in the deep ocean.

  16. An integrated GIS application system for soil moisture data assimilation

    Science.gov (United States)

    Wang, Di; Shen, Runping; Huang, Xiaolong; Shi, Chunxiang

    2014-11-01

    The gaps in knowledge and existing challenges in precisely describing the land surface process make it critical to represent the massive soil moisture data visually and mine the data for further research.This article introduces a comprehensive soil moisture assimilation data analysis system, which is instructed by tools of C#, IDL, ArcSDE, Visual Studio 2008 and SQL Server 2005. The system provides integrated service, management of efficient graphics visualization and analysis of land surface data assimilation. The system is not only able to improve the efficiency of data assimilation management, but also comprehensively integrate the data processing and analysis tools into GIS development environment. So analyzing the soil moisture assimilation data and accomplishing GIS spatial analysis can be realized in the same system. This system provides basic GIS map functions, massive data process and soil moisture products analysis etc. Besides,it takes full advantage of a spatial data engine called ArcSDE to effeciently manage, retrieve and store all kinds of data. In the system, characteristics of temporal and spatial pattern of soil moiture will be plotted. By analyzing the soil moisture impact factors, it is possible to acquire the correlation coefficients between soil moisture value and its every single impact factor. Daily and monthly comparative analysis of soil moisture products among observations, simulation results and assimilations can be made in this system to display the different trends of these products. Furthermore, soil moisture map production function is realized for business application.

  17. Development Of A Data Assimilation Capability For RAPID

    Science.gov (United States)

    Emery, C. M.; David, C. H.; Turmon, M.; Hobbs, J.; Allen, G. H.; Famiglietti, J. S.

    2017-12-01

    The global decline of in situ observations associated with the increasing ability to monitor surface water from space motivates the creation of data assimilation algorithms that merge computer models and space-based observations to produce consistent estimates of terrestrial hydrology that fill the spatiotemporal gaps in observations. RAPID is a routing model based on the Muskingum method that is capable of estimating river streamflow over large scales with a relatively short computing time. This model only requires limited inputs: a reach-based river network, and lateral surface and subsurface flow into the rivers. The relatively simple model physics imply that RAPID simulations could be significantly improved by including a data assimilation capability. Here we present the early developments of such data assimilation approach into RAPID. Given the linear and matrix-based structure of the model, we chose to apply a direct Kalman filter, hence allowing for the preservation of high computational speed. We correct the simulated streamflows by assimilating streamflow observations and our early results demonstrate the feasibility of the approach. Additionally, the use of in situ gauges at continental scales motivates the application of our new data assimilation scheme to altimetry measurements from existing (e.g. EnviSat, Jason 2) and upcoming satellite missions (e.g. SWOT), and ultimately apply the scheme globally.

  18. Multiscale Data Assimilation for Large-Eddy Simulations

    Science.gov (United States)

    Li, Z.; Cheng, X.; Gustafson, W. I., Jr.; Xiao, H.; Vogelmann, A. M.; Endo, S.; Toto, T.

    2017-12-01

    Large-eddy simulation (LES) is a powerful tool for understanding atmospheric turbulence, boundary layer physics and cloud development, and there is a great need for developing data assimilation methodologies that can constrain LES models. The U.S. Department of Energy Atmospheric Radiation Measurement (ARM) User Facility has been developing the capability to routinely generate ensembles of LES. The LES ARM Symbiotic Simulation and Observation (LASSO) project (https://www.arm.gov/capabilities/modeling/lasso) is generating simulations for shallow convection days at the ARM Southern Great Plains site in Oklahoma. One of major objectives of LASSO is to develop the capability to observationally constrain LES using a hierarchy of ARM observations. We have implemented a multiscale data assimilation (MSDA) scheme, which allows data assimilation to be implemented separately for distinct spatial scales, so that the localized observations can be effectively assimilated to constrain the mesoscale fields in the LES area of about 15 km in width. The MSDA analysis is used to produce forcing data that drive LES. With such LES workflow we have examined 13 days with shallow convection selected from the period May-August 2016. We will describe the implementation of MSDA, present LES results, and address challenges and opportunities for applying data assimilation to LES studies.

  19. Assimilating uncertain, dynamic and intermittent streamflow observations in hydrological models

    Science.gov (United States)

    Mazzoleni, Maurizio; Alfonso, Leonardo; Chacon-Hurtado, Juan; Solomatine, Dimitri

    2015-09-01

    Catastrophic floods cause significant socio-economical losses. Non-structural measures, such as real-time flood forecasting, can potentially reduce flood risk. To this end, data assimilation methods have been used to improve flood forecasts by integrating static ground observations, and in some cases also remote sensing observations, within water models. Current hydrologic and hydraulic research works consider assimilation of observations coming from traditional, static sensors. At the same time, low-cost, mobile sensors and mobile communication devices are becoming also increasingly available. The main goal and innovation of this study is to demonstrate the usefulness of assimilating uncertain streamflow observations that are dynamic in space and intermittent in time in the context of two different semi-distributed hydrological model structures. The developed method is applied to the Brue basin, where the dynamic observations are imitated by the synthetic observations of discharge. The results of this study show how model structures and sensors locations affect in different ways the assimilation of streamflow observations. In addition, it proves how assimilation of such uncertain observations from dynamic sensors can provide model improvements similar to those of streamflow observations coming from a non-optimal network of static physical sensors. This can be a potential application of recent efforts to build citizen observatories of water, which can make the citizens an active part in information capturing, evaluation and communication, helping simultaneously to improvement of model-based flood forecasting.

  20. Assimilation of GNSS radio occultation observations in GRAPES

    Science.gov (United States)

    Liu, Y.; Xue, J.

    2014-07-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction) analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3) satellites, the research status of the RO of FY-3 satellites is also presented.

  1. Assimilating the Future for Better Forecasts and Earlier Warnings

    Science.gov (United States)

    Du, H.; Wheatcroft, E.; Smith, L. A.

    2016-12-01

    Multi-model ensembles have become popular tools to account for some of the uncertainty due to model inadequacy in weather and climate simulation-based predictions. The current multi-model forecasts focus on combining single model ensemble forecasts by means of statistical post-processing. Assuming each model is developed independently or with different primary target variables, each is likely to contain different dynamical strengths and weaknesses. Using statistical post-processing, such information is only carried by the simulations under a single model ensemble: no advantage is taken to influence simulations under the other models. A novel methodology, named Multi-model Cross Pollination in Time, is proposed for multi-model ensemble scheme with the aim of integrating the dynamical information regarding the future from each individual model operationally. The proposed approach generates model states in time via applying data assimilation scheme(s) to yield truly "multi-model trajectories". It is demonstrated to outperform traditional statistical post-processing in the 40-dimensional Lorenz96 flow. Data assimilation approaches are originally designed to improve state estimation from the past to the current time. The aim of this talk is to introduce a framework that uses data assimilation to improve model forecasts at future time (not to argue for any one particular data assimilation scheme). Illustration of applying data assimilation "in the future" to provide early warning of future high-impact events is also presented.

  2. Net ecosystem carbon exchange in three contrasting Mediterranean ecosystems – the effect of drought

    Directory of Open Access Journals (Sweden)

    T. S. David

    2007-09-01

    Full Text Available Droughts reduce gross primary production (GPP and ecosystem respiration (Reco, contributing to most of the inter-annual variability in terrestrial carbon sequestration. In seasonally dry climates (Mediterranean, droughts result from reductions in annual rainfall and changes in rain seasonality. We compared carbon fluxes measured by the eddy covariance technique in three contrasting ecosystems in southern Portugal: an evergreen oak woodland (savannah-like with ca.~21% tree crown cover, a grassland dominated by herbaceous annuals and a coppiced short-rotation eucalyptus plantation. During the experimental period (2003–2006 the eucalyptus plantation was always the strongest sink for carbon: net ecosystem exchange rate (NEE between −861 and −399 g C m−2 year−1. The oak woodland and the grassland were much weaker sinks for carbon: NEE varied in the oak woodland between −140 and −28 g C m−2 year−1 and in the grassland between −190 and +49 g C m−2 year−1. The eucalyptus stand had higher GPP and a lower proportion of GPP spent in respiration than the other systems. The higher GPP resulted from high leaf area duration (LAD, as a surrogate for the photosynthetic photon flux density absorbed by the canopy. The eucalyptus had also higher rain use efficiency (GPP per unit of rain volume and light use efficiency (the daily GPP per unit incident photosynthetic photon flux density than the other two ecosystems. The effects of a severe drought could be evaluated during the hydrological-year (i.e., from October to September of 2004–2005. Between October 2004 and June 2005 the precipitation was only 40% of the long-term average. In 2004–2005 all ecosystems had GPP lower than in wetter years and carbon sequestration was strongly restricted (less negative NEE. The grassland was a net source of carbon dioxide (+49 g C m−2 year−1. In the oak woodland a large proportion of GPP resulted from carbon assimilated by its annual vegetation

  3. The Uniframe .Net Web Service Discovery Service

    National Research Council Canada - National Science Library

    Berbeco, Robert W

    2003-01-01

    Microsoft .NET allows the creation of distributed systems in a seamless manner Within NET small, discrete applications, referred to as Web services, are utilized to connect to each other or larger applications...

  4. Long Term RadNet Quality Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This RadNet Quality Data Asset includes all data since initiation and when ERAMS was expanded to become RadNet, name changed to reflect new mission. This includes...

  5. Special Section on Coloured Petri Nets

    DEFF Research Database (Denmark)

    1998-01-01

    Special section on coloured Petri nets, their basic concepts, analysis methods, tool support and industrial applications.......Special section on coloured Petri nets, their basic concepts, analysis methods, tool support and industrial applications....

  6. Aktivasi Keterlibatan Publik dalam Program Berita ‘NET 10’

    Directory of Open Access Journals (Sweden)

    Dinar Safa Anggraeni

    2017-06-01

    Full Text Available This research entitled Activation of The Public Engagement in `NET 10` News Program. An intrinsic case study by Robert E. Stake on Activating The Public Engagement in `NET 10` Citizen Journalism NET TV’s News Program. This research aimed to understand NET TV’s public management strategy in 'NET 10' news program. In addition, this research also aimed to determine how the editorial staff considere the standard of news value and news judgment on citizen journalist news, and the function of public sphere in the mass media of citizen journalism. The method used qualitative research with intrinsic case study approach by Robert E. Stake to NET TV’s editorial. The results showed the editorial’s strategy of public management by following action: (1 provided easily of joining  'NET CJ', (2 created  campaigns to increase the number of CJ, (3 nature CJ by keeping good and giving relationship evaluations, (4 provides rewards for the creator of CJ news aired in 'NET 10', and (5 educates CJ in making a citizen journalism news. NET TV used curation techniques in the process of citizen journalism news gatekeeper to keep the news value and news judment standard of citizen journalism news. Unfortunately, ‘NET 10’’s citizen journalism news rate of the proportion of news comprehensive continues to fall down because the editorial put loyalty forward. 'NET CJ' act as a opinions catalyst of the citizens to the government.

  7. Towards new information resources for public health--from WordNet to MedicalWordNet.

    Science.gov (United States)

    Fellbaum, Christiane; Hahn, Udo; Smith, Barry

    2006-06-01

    In the last two decades, WordNet has evolved as the most comprehensive computational lexicon of general English. In this article, we discuss its potential for supporting the creation of an entirely new kind of information resource for public health, viz. MedicalWordNet. This resource is not to be conceived merely as a lexical extension of the original WordNet to medical terminology; indeed, there is already a considerable degree of overlap between WordNet and the vocabulary of medicine. Instead, we propose a new type of repository, consisting of three large collections of (1) medically relevant word forms, structured along the lines of the existing Princeton WordNet; (2) medically validated propositions, referred to here as medical facts, which will constitute what we shall call MedicalFactNet; and (3) propositions reflecting laypersons' medical beliefs, which will constitute what we shall call the MedicalBeliefNet. We introduce a methodology for setting up the MedicalWordNet. We then turn to the discussion of research challenges that have to be met to build this new type of information resource. We build a database of sentences relevant to the medical domain. The sentences are generated from WordNet via its relations as well as from medical statements broken down into elementary propositions. Two subcorpora of sentences are distinguished, MedicalBeliefNet and MedicalFactNet. The former is rated for assent by laypersons; the latter for correctness by medical experts. The sentence corpora will be valuable for a variety of applications in information retrieval as well as in research in linguistics and psychology with respect to the study of expert and non-expert beliefs and their linguistic expressions. Our work has to meet several considerable challenges. These include accounting for the distinction between medical experts and laypersons, the social issues of expert-layperson communication in different media, the linguistic aspects of encoding medical knowledge, and

  8. NetBeans IDE 8 cookbook

    CERN Document Server

    Salter, David

    2014-01-01

    If you're a Java developer of any level using NetBeans and want to learn how to get the most out of NetBeans, then this book is for you. Learning how to utilize NetBeans will provide a firm foundation for your Java application development.

  9. History-dependent stochastic Petri nets

    NARCIS (Netherlands)

    Schonenberg, H.; Sidorova, N.; Aalst, van der W.M.P.; Hee, van K.M.; Pnueli, A.; Virbitskaite, I.; Voronkov, A.

    2010-01-01

    Stochastic Petri Nets are a useful and well-known tool for performance analysis. However, an implicit assumption in the different types of Stochastic Petri Nets is the Markov property. It is assumed that a choice in the Petri net only depends on the current state and not on earlier choices. For many

  10. Putting Petri nets to work in Industry

    NARCIS (Netherlands)

    Aalst, van der W.M.P.

    1994-01-01

    Petri nets exist for over 30 years. Especially in the last decade Petri nets have been put into practive extensively. Thanks to several useful extensions and the availability of computer tools, Petri nets have become a mature tool for modelling and analysing industrial systems. This paper describes

  11. Aplicació Microsoft .Net : Hotel Spa

    OpenAIRE

    Marquès Palmer, Jordi

    2010-01-01

    Desenvolupament d'una aplicació amb Microsoft .NET, WCF, WPF, Linq2SQL, d'un Hotel Spa. Desarrollo de una aplicación con Microsoft .NET, WCF, WPF, Linq2SQL, de un Hotel Spa. Application development using Microsoft .NET, WCF, WPF, Linq2SQL, for a Spa Hotel.

  12. Delta Semantics Defined By Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kyng, Morten; Madsen, Ole Lehrmann

    and the possibility of using predicates to specify state changes. In this paper a formal semantics for Delta is defined and analysed using Petri nets. Petri nets was chosen because the ideas behind Petri nets and Delta concide on several points. A number of proposals for changes in Delta, which resulted from...

  13. The K-NET - A year after

    International Nuclear Information System (INIS)

    Kinoshita, S.; Ohtani, K.; Katayama, T.

    2001-01-01

    We started to release the K-NET strong-motion data from June 1996 and about one year passed. In this article, we report the development of K-NET and some applications using the K-NET information released on the Internet. (author)

  14. 47 CFR 65.500 - Net income.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net income. 65.500 Section 65.500... OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Interexchange Carriers § 65.500 Net income. The net income methodology specified in § 65.450 shall be utilized by all interexchange carriers that are...

  15. 47 CFR 65.450 - Net income.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net income. 65.450 Section 65.450... OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Exchange Carriers § 65.450 Net income. (a) Net income shall consist of all revenues derived from the provision of interstate telecommunications services...

  16. INMARSAT-C SafetyNET

    Science.gov (United States)

    Tsunamis 406 EPIRB's National Weather Service Marine Forecasts INMARSAT-C SafetyNET Marine Forecast Offices greater danger near shore or any shallow waters? NATIONAL WEATHER SERVICE PRODUCTS VIA INMARSAT-C SafetyNET Inmarsat-C SafetyNET is an internationally adopted, automated satellite system for promulgating

  17. Storm surge model based on variational data assimilation method

    Directory of Open Access Journals (Sweden)

    Shi-li Huang

    2010-06-01

    Full Text Available By combining computation and observation information, the variational data assimilation method has the ability to eliminate errors caused by the uncertainty of parameters in practical forecasting. It was applied to a storm surge model based on unstructured grids with high spatial resolution meant for improving the forecasting accuracy of the storm surge. By controlling the wind stress drag coefficient, the variation-based model was developed and validated through data assimilation tests in an actual storm surge induced by a typhoon. In the data assimilation tests, the model accurately identified the wind stress drag coefficient and obtained results close to the true state. Then, the actual storm surge induced by Typhoon 0515 was forecast by the developed model, and the results demonstrate its efficiency in practical application.

  18. a Thtee-Dimensional Variational Assimilation Scheme for Satellite Aod

    Science.gov (United States)

    Liang, Y.; Zang, Z.; You, W.

    2018-04-01

    A three-dimensional variational data assimilation scheme is designed for satellite AOD based on the IMPROVE (Interagency Monitoring of Protected Visual Environments) equation. The observation operator that simulates AOD from the control variables is established by the IMPROVE equation. All of the 16 control variables in the assimilation scheme are the mass concentrations of aerosol species from the Model for Simulation Aerosol Interactions and Chemistry scheme, so as to take advantage of this scheme in providing comprehensive analyses of species concentrations and size distributions as well as be calculating efficiently. The assimilation scheme can save computational resources as the IMPROVE equation is a quadratic equation. A single-point observation experiment shows that the information from the single-point AOD is effectively spread horizontally and vertically.

  19. Data Assimilation in Hydrodynamic Models of Continental Shelf Seas

    DEFF Research Database (Denmark)

    Sørensen, Jacob Viborg Tornfeldt

    2004-01-01

    . Assimilation of sea surface temperature and parameter estimation in hydrodynamic models are also considered. The main focus has been on the development of robust and efficient techniques applicable in real operational settings. The applied assimilation techniques all use a Kalman filter approach. They consist....... The assimilation schemes used in this work are primarily based on two ensemble based schemes, the Ensemble Kalman Filter and the Reduced Rank Square Root Kalman Filter. In order to investigate the applicability of these and derived schemes, the sensitivity to filter parameters, nonlinearity and bias is examined...... in artificial tests. Approximate schemes, which are theoretically presented as using regularised Kalman gains, are introduced and successfully applied in artificial as well real case scenarios. Particularly, distant dependent and slowly time varying or constant Kalman gains are shown to possess good hindcast...

  20. Basis Risk and Net Interest Income of Banks

    Directory of Open Access Journals (Sweden)

    Mielus Piotr

    2016-12-01

    Full Text Available The results of the banking sector are shaped primarily by commissions and net interest income. Net interest income is determined by the difference between the profitability of bank assets and liabilities. In the case when a different method is used to determine interest for each side of the balance sheet, there occurs a basis risk that may lead to the deterioration in the net interest income of the sector. This is the situation in the Polish banking sector, which is characterized by the presence of variable interest rates for long-term assets and fixed interest rates for short-term liabilities. The study aims to verify the following thesis: in an environment of falling interest rates we can observe the deterioration in net interest income of the banking sector, as a result of the materialization of the basis risk. The authors of the article state that the source of the basis risk is the mismatch between the reference rate used to define the interest flow of loans and the actual cost of financing the balance through term deposits collected from non-financial entities.

  1. The Impact of the Assimilation of Aquarius Sea Surface Salinity Data in the GEOS Ocean Data Assimilation System

    Science.gov (United States)

    Vernieres, Guillaume Rene Jean; Kovach, Robin M.; Keppenne, Christian L.; Akella, Santharam; Brucker, Ludovic; Dinnat, Emmanuel Phillippe

    2014-01-01

    Ocean salinity and temperature differences drive thermohaline circulations. These properties also play a key role in the ocean-atmosphere coupling. With the availability of L-band space-borne observations, it becomes possible to provide global scale sea surface salinity (SSS) distribution. This study analyzes globally the along-track (Level 2) Aquarius SSS retrievals obtained using both passive and active L-band observations. Aquarius alongtrack retrieved SSS are assimilated into the ocean data assimilation component of Version 5 of the Goddard Earth Observing System (GEOS-5) assimilation and forecast model. We present a methodology to correct the large biases and errors apparent in Version 2.0 of the Aquarius SSS retrieval algorithm and map the observed Aquarius SSS retrieval into the ocean models bulk salinity in the topmost layer. The impact of the assimilation of the corrected SSS on the salinity analysis is evaluated by comparisons with insitu salinity observations from Argo. The results show a significant reduction of the global biases and RMS of observations-minus-forecast differences at in-situ locations. The most striking results are found in the tropics and southern latitudes. Our results highlight the complementary role and problems that arise during the assimilation of salinity information from in-situ (Argo) and space-borne surface (SSS) observations

  2. Net-infiltration map of the Navajo Sandstone outcrop area in western Washington County, Utah

    Science.gov (United States)

    Heilweil, Victor M.; McKinney, Tim S.

    2007-01-01

    As populations grow in the arid southwestern United States and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration and recharge becomes critically important for inventorying groundwater resources and mapping contamination vulnerability. A Geographic Information System (GIS)-based model utilizing readily available soils, topographic, precipitation, and outcrop data has been developed for predicting net infiltration to exposed and soil-covered areas of the Navajo Sandstone outcrop of southwestern Utah. The Navajo Sandstone is an important regional bedrock aquifer. The GIS model determines the net-infiltration percentage of precipitation by using an empirical equation. This relation is derived from least squares linear regression between three surficial parameters (soil coarseness, topographic slope, and downgradient distance from outcrop) and the percentage of estimated net infiltration based on environmental tracer data from excavations and boreholes at Sand Hollow Reservoir in the southeastern part of the study area.Processed GIS raster layers are applied as parameters in the empirical equation for determining net infiltration for soil-covered areas as a percentage of precipitation. This net-infiltration percentage is multiplied by average annual Parameter-elevation Regressions on Independent Slopes Model (PRISM) precipitation data to obtain an infiltration rate for each model cell. Additionally, net infiltration on exposed outcrop areas is set to 10 percent of precipitation on the basis of borehole net-infiltration estimates. Soils and outcrop net-infiltration rates are merged to form a final map.Areas of low, medium, and high potential for ground-water recharge have been identified, and estimates of net infiltration range from 0.1 to 66 millimeters per year (mm/yr). Estimated net-infiltration rates of less than 10 mm/yr are considered low, rates of 10 to 50 mm/yr are

  3. Assimilating bio-optical glider data during a phytoplankton bloom in the southern Ross Sea

    Directory of Open Access Journals (Sweden)

    D. E. Kaufman

    2018-01-01

    Full Text Available The Ross Sea is a region characterized by high primary productivity in comparison to other Antarctic coastal regions, and its productivity is marked by considerable variability both spatially (1–50 km and temporally (days to weeks. This variability presents a challenge for inferring phytoplankton dynamics from observations that are limited in time or space, which is often the case due to logistical limitations of sampling. To better understand the spatiotemporal variability in Ross Sea phytoplankton dynamics and to determine how restricted sampling may skew dynamical interpretations, high-resolution bio-optical glider measurements were assimilated into a one-dimensional biogeochemical model adapted for the Ross Sea. The assimilation of data from the entire glider track using the micro-genetic and local search algorithms in the Marine Model Optimization Testbed improves the model–data fit by  ∼ 50 %, generating rates of integrated primary production of 104 g C m−2 yr−1 and export at 200 m of 27 g C m−2 yr−1. Assimilating glider data from three different latitudinal bands and three different longitudinal bands results in minimal changes to the simulations, improves the model–data fit with respect to unassimilated data by  ∼ 35 %, and confirms that analyzing these glider observations as a time series via a one-dimensional model is reasonable on these scales. Whereas assimilating the full glider data set produces well-constrained simulations, assimilating subsampled glider data at a frequency consistent with cruise-based sampling results in a wide range of primary production and export estimates. These estimates depend strongly on the timing of the assimilated observations, due to the presence of high mesoscale variability in this region. Assimilating surface glider data subsampled at a frequency consistent with available satellite-derived data results in 40 % lower carbon export, primarily

  4. Assimilation of satellite color observations in a coupled ocean GCM-ecosystem model

    Science.gov (United States)

    Sarmiento, Jorge L.

    1992-01-01

    Monthly average coastal zone color scanner (CZCS) estimates of chlorophyll concentration were assimilated into an ocean global circulation model(GCM) containing a simple model of the pelagic ecosystem. The assimilation was performed in the simplest possible manner, to allow the assessment of whether there were major problems with the ecosystem model or with the assimilation procedure. The current ecosystem model performed well in some regions, but failed in others to assimilate chlorophyll estimates without disrupting important ecosystem properties. This experiment gave insight into those properties of the ecosystem model that must be changed to allow data assimilation to be generally successful, while raising other important issues about the assimilation procedure.

  5. Biomass assimilation in coupled ecohydrodynamical model of the Mediterranean Sea

    Science.gov (United States)

    Crispi, G.; Bournaski, E.; Crise, A.

    2003-04-01

    Data assimilation has raised new interest in the last years in the context of the environmental sciences. The swift increment of the attention paid to it in oceanography is due to the coming age of operational services for the marine environment which is going to dramatically increase the demand for accurate, timely and reliable estimates of the space and time distribution both for physical and in a near future for biogeochemical fields. Data assimilation combines information derived from measurements with knowledge of the rules that govern the evolution of the system of interest through formalization and implementation in numerical models. The importance of ocean data assimilation has been recognized by several international programmes as JGOFS, GOOS and CLIVAR. This work presents an eco-hydrodynamic model of the Mediterranean Sea developed at the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, Trieste, Italy. It includes 3-D MOM-based hydrodynamics of the Mediterranean Sea, coupled with biochemical model of Nitrogen, Phytoplankton, Zooplankton, and Detritus (NPZD). Monthly mean wind forcings are adopted to force this MOM-NPZD model. For better prediction and analysis of N, P, Z and D distributions in the sea the model needs data assimilation from biomass observations on the sea surface. Chosen approach for evaluating performances of data assimilation techniques in coupled model is the definition of a twin experiment testbed where a reference run is carried out assuming its result as the truth. We define a sampling strategy to obtain different datasets to be incorporated in another ecological model in successive runs in order to appraise the potential of the data assimilation and sampling strategy. The runs carried out with different techniques and different spatio-temporal coverages are compared in order to evaluate the sensitivity to different coverage of dataset. The discussed alternative way is to assume the ecosystem at steady state and

  6. Ensemble streamflow assimilation with the National Water Model.

    Science.gov (United States)

    Rafieeinasab, A.; McCreight, J. L.; Noh, S.; Seo, D. J.; Gochis, D.

    2017-12-01

    Through case studies of flooding across the US, we compare the performance of the National Water Model (NWM) data assimilation (DA) scheme to that of a newly implemented ensemble Kalman filter approach. The NOAA National Water Model (NWM) is an operational implementation of the community WRF-Hydro modeling system. As of August 2016, the NWM forecasts of distributed hydrologic states and fluxes (including soil moisture, snowpack, ET, and ponded water) over the contiguous United States have been publicly disseminated by the National Center for Environmental Prediction (NCEP) . It also provides streamflow forecasts at more than 2.7 million river reaches up to 30 days in advance. The NWM employs a nudging scheme to assimilate more than 6,000 USGS streamflow observations and provide initial conditions for its forecasts. A problem with nudging is how the forecasts relax quickly to open-loop bias in the forecast. This has been partially addressed by an experimental bias correction approach which was found to have issues with phase errors during flooding events. In this work, we present an ensemble streamflow data assimilation approach combining new channel-only capabilities of the NWM and HydroDART (a coupling of the offline WRF-Hydro model and NCAR's Data Assimilation Research Testbed; DART). Our approach focuses on the single model state of discharge and incorporates error distributions on channel-influxes (overland and groundwater) in the assimilation via an ensemble Kalman filter (EnKF). In order to avoid filter degeneracy associated with a limited number of ensemble at large scale, DART's covariance inflation (Anderson, 2009) and localization capabilities are implemented and evaluated. The current NWM data assimilation scheme is compared to preliminary results from the EnKF application for several flooding case studies across the US.

  7. Assimilation of satellite altimeter data into an open ocean model

    Science.gov (United States)

    Vogeler, Armin; SchröTer, Jens

    1995-08-01

    Geosat sea surface height data are assimilated into an eddy-resolving quasi-geostrophic open ocean model using the adjoint technique. The method adjusts the initial conditions for all layers and is successful on the timescale of a few weeks. Time-varying values for the open boundaries are prescribed by a much larger quasi-geostrophic model of the Antarctic Circumpolar Current (ACC). Both models have the same resolution of approximately 20×20 km (1/3°×1/6°), have three layers, and include realistic bottom topography and coastlines. The open model box is embedded in the African sector of the ACC. For continuous assimilation of satellite data into the larger model the nudging technique is applied. These results are used for the adjoint optimization procedure as boundary conditions and as a first guess for the initial condition. For the open model box the difference between model and satellite sea surface height that remains after the nudging experiment amounts to a 19-cm root-mean-square error (rmse). By assimilation into the regional model this value can be reduced to a 6-cm rmse for an assimilation period of 20 days. Several experiments which attempt to improve the convergence of the iterative optimization method are reported. Scaling and regularization by smoothing have to be applied carefully. Especially during the first 10 iterations, the convergence can be improved considerably by low-pass filtering of the cost function gradient. The result of a perturbation experiment shows that for longer assimilation periods the influence of the boundary values becomes dominant and they should be determined inversely by data assimilation into the open ocean model.

  8. Assimilation scheme of the Mediterranean Forecasting System: operational implementation

    Directory of Open Access Journals (Sweden)

    E. Demirov

    Full Text Available This paper describes the operational implementation of the data assimilation scheme for the Mediterranean Forecasting System Pilot Project (MFSPP. The assimilation scheme, System for Ocean Forecast and Analysis (SOFA, is a reduced order Optimal Interpolation (OI scheme. The order reduction is achieved by projection of the state vector into vertical Empirical Orthogonal Functions (EOF. The data assimilated are Sea Level Anomaly (SLA and temperature profiles from Expandable Bathy Termographs (XBT. The data collection, quality control, assimilation and forecast procedures are all done in Near Real Time (NRT. The OI is used intermittently with an assimilation cycle of one week so that an analysis is produced once a week. The forecast is then done for ten days following the analysis day. The root mean square (RMS between the model forecast and the analysis (the forecast RMS is below 0.7°C in the surface layers and below 0.2°C in the layers deeper than 200 m for all the ten forecast days. The RMS between forecast and initial condition (persistence RMS is higher than forecast RMS after the first day. This means that the model improves forecast with respect to persistence. The calculation of the misfit between the forecast and the satellite data suggests that the model solution represents well the main space and time variability of the SLA except for a relatively short period of three – four weeks during the summer when the data show a fast transition between the cyclonic winter and anti-cyclonic summer regimes. This occurs in the surface layers that are not corrected by our assimilation scheme hypothesis. On the basis of the forecast skill scores analysis, conclusions are drawn about future improvements.

    Key words. Oceanography; general (marginal and semi-enclosed seas; numerical modeling; ocean prediction

  9. Assimilation scheme of the Mediterranean Forecasting System: operational implementation

    Directory of Open Access Journals (Sweden)

    E. Demirov

    2003-01-01

    Full Text Available This paper describes the operational implementation of the data assimilation scheme for the Mediterranean Forecasting System Pilot Project (MFSPP. The assimilation scheme, System for Ocean Forecast and Analysis (SOFA, is a reduced order Optimal Interpolation (OI scheme. The order reduction is achieved by projection of the state vector into vertical Empirical Orthogonal Functions (EOF. The data assimilated are Sea Level Anomaly (SLA and temperature profiles from Expandable Bathy Termographs (XBT. The data collection, quality control, assimilation and forecast procedures are all done in Near Real Time (NRT. The OI is used intermittently with an assimilation cycle of one week so that an analysis is produced once a week. The forecast is then done for ten days following the analysis day. The root mean square (RMS between the model forecast and the analysis (the forecast RMS is below 0.7°C in the surface layers and below 0.2°C in the layers deeper than 200 m for all the ten forecast days. The RMS between forecast and initial condition (persistence RMS is higher than forecast RMS after the first day. This means that the model improves forecast with respect to persistence. The calculation of the misfit between the forecast and the satellite data suggests that the model solution represents well the main space and time variability of the SLA except for a relatively short period of three – four weeks during the summer when the data show a fast transition between the cyclonic winter and anti-cyclonic summer regimes. This occurs in the surface layers that are not corrected by our assimilation scheme hypothesis. On the basis of the forecast skill scores analysis, conclusions are drawn about future improvements. Key words. Oceanography; general (marginal and semi-enclosed seas; numerical modeling; ocean prediction

  10. Uptake of mercury vapor by wheat. An assimilation model

    International Nuclear Information System (INIS)

    Browne, C.L.; Fang, S.C.

    1978-01-01

    Using a whole-plant chamber and 203 Hg-labeled mercury, a quantitative study was made of the effect of environmental parameters on the uptake, by wheat (Triticum aestivum), of metallic mercury vapor, an atmospheric pollutant. Factors were examined in relation to their influence on components of the gas-assimilation model, U(Hg) = (C/sub A' -- C/sub L')/(r/sub L.Hg/ + r/sub M.Hg/) where U(Hg) is the rate of mercury uptake per unit leaf surface, C/sub A'/ is the ambient mercury vapor concentration, C/sub L'/ is the mercury concentration at immobilization sites within the plant (assumed to be zero), r/sub L.Hg/ is the total leaf resistance to mercury vapor exchange, and r/sub M.Hg/ is a residual term to account for unexplained physical and biochemical resistances to mercury vapor uptake. Essentially all mercury vapor uptake was confined to the leaves. r/sub L.Hg/ was particularly influenced by illumination (0 to 12.8 klux), but unaffected by ambient temperature (17 to 33 0 C) and mercury vapor concentration (0 to 40 μg m -3 ). The principal limitation to mercury vapor uptake was r/sub M.Hg/, which was linearly related to leaf temperature, but unaffected by mercury vapor concentration and illumination, except for apparent high values in darkness. Knowing C/sub A'/ and estimating r/sub L.Hg/ and r/sub M.Hg/ from experimental data, mercury vapor uptake by wheat in light was accurately predicted for several durations of exposure using the above model

  11. NET 40 Generics Beginner's Guide

    CERN Document Server

    Mukherjee, Sudipta

    2012-01-01

    This is a concise, practical guide that will help you learn Generics in .NET, with lots of real world and fun-to-build examples and clear explanations. It is packed with screenshots to aid your understanding of the process. This book is aimed at beginners in Generics. It assumes some working knowledge of C# , but it isn't mandatory. The following would get the most use out of the book: Newbie C# developers struggling with Generics. Experienced C++ and Java Programmers who are migrating to C# and looking for an alternative to other generic frameworks like STL and JCF would find this book handy.

  12. Assimilation of LAI time-series in crop production models

    Science.gov (United States)

    Kooistra, Lammert; Rijk, Bert; Nannes, Louis

    2014-05-01

    Agriculture is worldwide a large consumer of freshwater, nutrients and land. Spatial explicit agricultural management activities (e.g., fertilization, irrigation) could significantly improve efficiency in resource use. In previous studies and operational applications, remote sensing has shown to be a powerful method for spatio-temporal monitoring of actual crop status. As a next step, yield forecasting by assimilating remote sensing based plant variables in crop production models would improve agricultural decision support both at the farm and field level. In this study we investigated the potential of remote sensing based Leaf Area Index (LAI) time-series assimilated in the crop production model LINTUL to improve yield forecasting at field level. The effect of assimilation method and amount of assimilated observations was evaluated. The LINTUL-3 crop production model was calibrated and validated for a potato crop on two experimental fields in the south of the Netherlands. A range of data sources (e.g., in-situ soil moisture and weather sensors, destructive crop measurements) was used for calibration of the model for the experimental field in 2010. LAI from cropscan field radiometer measurements and actual LAI measured with the LAI-2000 instrument were used as input for the LAI time-series. The LAI time-series were assimilated in the LINTUL model and validated for a second experimental field on which potatoes were grown in 2011. Yield in 2011 was simulated with an R2 of 0.82 when compared with field measured yield. Furthermore, we analysed the potential of assimilation of LAI into the LINTUL-3 model through the 'updating' assimilation technique. The deviation between measured and simulated yield decreased from 9371 kg/ha to 8729 kg/ha when assimilating weekly LAI measurements in the LINTUL model over the season of 2011. LINTUL-3 furthermore shows the main growth reducing factors, which are useful for farm decision support. The combination of crop models and sensor

  13. Multivariate and multiscale data assimilation in terrestrial systems: a review.

    Science.gov (United States)

    Montzka, Carsten; Pauwels, Valentijn R N; Franssen, Harrie-Jan Hendricks; Han, Xujun; Vereecken, Harry

    2012-11-26

    More and more terrestrial observational networks are being established to monitor climatic, hydrological and land-use changes in different regions of the World. In these networks, time series of states and fluxes are recorded in an automated manner, often with a high temporal resolution. These data are important for the understanding of water, energy, and/or matter fluxes, as well as their biological and physical drivers and interactions with and within the terrestrial system. Similarly, the number and accuracy of variables, which can be observed by spaceborne sensors, are increasing. Data assimilation (DA) methods utilize these observations in terrestrial models in order to increase process knowledge as well as to improve forecasts for the system being studied. The widely implemented automation in observing environmental states and fluxes makes an operational computation more and more feasible, and it opens the perspective of short-time forecasts of the state of terrestrial systems. In this paper, we review the state of the art with respect to DA focusing on the joint assimilation of observational data precedents from different spatial scales and different data types. An introduction is given to different DA methods, such as the Ensemble Kalman Filter (EnKF), Particle Filter (PF) and variational methods (3/4D-VAR). In this review, we distinguish between four major DA approaches: (1) univariate single-scale DA (UVSS), which is the approach used in the majority of published DA applications, (2) univariate multiscale DA (UVMS) referring to a methodology which acknowledges that at least some of the assimilated data are measured at a different scale than the computational grid scale, (3) multivariate single-scale DA (MVSS) dealing with the assimilation of at least two different data types, and (4) combined multivariate multiscale DA (MVMS). Finally, we conclude with a discussion on the advantages and disadvantages of the assimilation of multiple data types in a

  14. Multivariate and Multiscale Data Assimilation in Terrestrial Systems: A Review

    Directory of Open Access Journals (Sweden)

    Harry Vereecken

    2012-11-01

    Full Text Available More and more terrestrial observational networks are being established to monitor climatic, hydrological and land-use changes in different regions of the World. In these networks, time series of states and fluxes are recorded in an automated manner, often with a high temporal resolution. These data are important for the understanding of water, energy, and/or matter fluxes, as well as their biological and physical drivers and interactions with and within the terrestrial system. Similarly, the number and accuracy of variables, which can be observed by spaceborne sensors, are increasing. Data assimilation (DA methods utilize these observations in terrestrial models in order to increase process knowledge as well as to improve forecasts for the system being studied. The widely implemented automation in observing environmental states and fluxes makes an operational computation more and more feasible, and it opens the perspective of short-time forecasts of the state of terrestrial systems. In this paper, we review the state of the art with respect to DA focusing on the joint assimilation of observational data precedents from different spatial scales and different data types. An introduction is given to different DA methods, such as the Ensemble Kalman Filter (EnKF, Particle Filter (PF and variational methods (3/4D-VAR. In this review, we distinguish between four major DA approaches: (1 univariate single-scale DA (UVSS, which is the approach used in the majority of published DA applications, (2 univariate multiscale DA (UVMS referring to a methodology which acknowledges that at least some of the assimilated data are measured at a different scale than the computational grid scale, (3 multivariate single-scale DA (MVSS dealing with the assimilation of at least two different data types, and (4 combined multivariate multiscale DA (MVMS. Finally, we conclude with a discussion on the advantages and disadvantages of the assimilation of multiple data types in a

  15. Reconstruction of Historical Weather by Assimilating Old Weather Diary Data

    Science.gov (United States)

    Neluwala, P.; Yoshimura, K.; Toride, K.; Hirano, J.; Ichino, M.; Okazaki, A.

    2017-12-01

    Climate can control not only human life style but also other living beings. It is important to investigate historical climate to understand the current and future climates. Information about daily weather can give a better understanding of past life on earth. Long-term weather influences crop calendar as well as the development of civilizations. Unfortunately, existing reconstructed daily weather data are limited to 1850s due to the availability of instrumental data. The climate data prior to that are derived from proxy materials (e.g., tree-ring width, ice core isotopes, etc.) which are either in annual or decadal scale. However, there are many historical documents which contain information about weather such as personal diaries. In Japan, around 20 diaries in average during the 16th - 19th centuries have been collected and converted into a digitized form. As such, diary data exist in many other countries. This study aims to reconstruct historical daily weather during the 18th and 19th centuries using personal daily diaries which have analogue weather descriptions such as `cloudy' or `sunny'. A recent study has shown the possibility of assimilating coarse weather data using idealized experiments. We further extend this study by assimilating modern weather descriptions similar to diary data in recent periods. The Global Spectral model (GSM) of National Centers for Environmental Prediction (NCEP) is used to reconstruct weather with the Local Ensemble Kalman filter (LETKF). Descriptive data are first converted to model variables such as total cloud cover (TCC), solar radiation and precipitation using empirical relationships. Those variables are then assimilated on a daily basis after adding random errors to consider the uncertainty of actual diary data. The assimilation of downward short wave solar radiation using weather descriptions improves RMSE from 64.3 w/m2 to 33.0 w/m2 and correlation coefficient (R) from 0.5 to 0.8 compared with the case without any

  16. SMAP Data Assimilation at NASA SPoRT

    Science.gov (United States)

    Blankenship, Clay B.; Case, Jonathan L.; Zavodsky, Bradley T.

    2016-01-01

    The NASA Short-Term Prediction Research and Transition (SPoRT) Center maintains a near-real- time run of the Noah Land Surface Model within the Land Information System (LIS) at 3-km resolution. Soil moisture products from this model are used by several NOAA/National Weather Service Weather Forecast Offices for flood and drought situational awareness. We have implemented assimilation of soil moisture retrievals from the Soil Moisture Ocean Salinity (SMOS) and Soil Moisture Active/ Passive (SMAP) satellites, and are now evaluating the SMAP assimilation. The SMAP-enhanced LIS product is planned for public release by October 2016.

  17. Assimilation of radar-based nowcast into HIRLAM NWP model

    DEFF Research Database (Denmark)

    Jensen, David Getreuer; Petersen, Claus; Rasmussen, Michael R.

    2015-01-01

    The present study introduces a nowcast scheme that assimilates radar extrapolation data (RED) into a nowcasting version of the high resolution limited area model (HIRLAM) numerical weather prediction (NWP) model covering the area of Denmark. The RED are based on the Co-TREC (tracking radar echoes...... by correlation) methodology and are generated from cleaned radar mosaics from the Danish weather radar network. The assimilation technique is a newly developed method that increases model precipitation by increasing low-level convergence and decreasing convergence aloft in order to increase the vertical velocity....... The level of improved predictability relies on the RED quality, which again relies on the type of event....

  18. Data assimilation in integrated hydrological modeling using ensemble Kalman filtering

    DEFF Research Database (Denmark)

    Rasmussen, Jørn; Madsen, H.; Jensen, Karsten Høgh

    2015-01-01

    Groundwater head and stream discharge is assimilated using the ensemble transform Kalman filter in an integrated hydrological model with the aim of studying the relationship between the filter performance and the ensemble size. In an attempt to reduce the required number of ensemble members...... and estimating parameters requires a much larger ensemble size than just assimilating groundwater head observations. However, the required ensemble size can be greatly reduced with the use of adaptive localization, which by far outperforms distance-based localization. The study is conducted using synthetic data...

  19. Establishment and analysis of a High-Resolution Assimilation Dataset of the water-energy cycle in China

    Science.gov (United States)

    Zhu, X.; Wen, X.; Zheng, Z.

    2017-12-01

    For better prediction and understanding of land-atmospheric interaction, in-situ observed meteorological data acquired from the China Meteorological Administration (CMA) were assimilated in the Weather Research and Forecasting (WRF) model and the monthly Green Vegetation Coverage (GVF) data, which was calculated using the Normalized Difference Vegetation Index (NDVI) of the Earth Observing System Moderate-Resolution Imaging Spectroradiometer (EOS-MODIS) and Digital Elevation Model (DEM) data of the Shuttle Radar Topography Mission (SRTM) system. Furthermore, the WRF model produced a High-Resolution Assimilation Dataset of the water-energy cycle in China (HRADC). This dataset has a horizontal resolution of 25 km for near surface meteorological data, such as air temperature, humidity, wind vectors and pressure (19 levels); soil temperature and moisture (four levels); surface temperature; downward/upward short/long radiation; 3-h latent heat flux; sensible heat flux; and ground heat flux. In this study, we 1) briefly introduce the cycling 3D-Var assimilation method and 2) compare results of meteorological elements, such as 2 m temperature and precipitation generated by the HRADC with the gridded observation data from CMA, and surface temperature and specific humidity with Global LandData Assimilation System (GLDAS) output data from the National Aeronautics and Space Administration (NASA). We found that the satellite-derived GVF from MODIS increased over southeast China compared with the default model over the whole year. The simulated results of soil temperature, net radiation and surface energy flux from the HRADC are improved compared with the control simulation and are close to GLDAS outputs. The values of net radiation from HRADC are higher than the GLDAS outputs, and the differences in the simulations are large in the east region but are smaller in northwest China and on the Qinghai-Tibet Plateau. The spatial distribution of the sensible heat flux and the ground

  20. Tsunami Modeling and Prediction Using a Data Assimilation Technique with Kalman Filters

    Science.gov (United States)

    Barnier, G.; Dunham, E. M.

    2016-12-01

    Earthquake-induced tsunamis cause dramatic damages along densely populated coastlines. It is difficult to predict and anticipate tsunami waves in advance, but if the earthquake occurs far enough from the coast, there may be enough time to evacuate the zones at risk. Therefore, any real-time information on the tsunami wavefield (as it propagates towards the coast) is extremely valuable for early warning systems. After the 2011 Tohoku earthquake, a dense tsunami-monitoring network (S-net) based on cabled ocean-bottom pressure sensors has been deployed along the Pacific coast in Northeastern Japan. Maeda et al. (GRL, 2015) introduced a data assimilation technique to reconstruct the tsunami wavefield in real time by combining numerical solution of the shallow water wave equations with additional terms penalizing the numerical solution for not matching observations. The penalty or gain matrix is determined though optimal interpolation and is independent of time. Here we explore a related data assimilation approach using the Kalman filter method to evolve the gain matrix. While more computationally expensive, the Kalman filter approach potentially provides more accurate reconstructions. We test our method on a 1D tsunami model derived from the Kozdon and Dunham (EPSL, 2014) dynamic rupture simulations of the 2011 Tohoku earthquake. For appropriate choices of model and data covariance matrices, the method reconstructs the tsunami wavefield prior to wave arrival at the coast. We plan to compare the Kalman filter method to the optimal interpolation method developed by Maeda et al. (GRL, 2015) and then to implement the method for 2D.

  1. Higher assimilation than respiration sensitivity to drought for a desert ecosystem in Central Asia.

    Science.gov (United States)

    Gu, Daxing; Otieno, Dennis; Huang, Yuqing; Wang, Quan

    2017-12-31

    Responses of ecosystem assimilation and respiration to global climate change vary considerably among terrestrial ecosystems constrained by both biotic and abiotic factors. In this study, net CO 2 exchange between ecosystem and atmosphere (NEE) was measured over a 4-year period (2013-2016) using eddy covariance technology in a desert ecosystem in Central Asia. Ecosystem assimilation (gross primary production, GPP) and respiration (R eco ) were derived from NEE by fitting light response curves to NEE data based on day- and nighttime data, and their responses to soil water content (SWC) and evaporative fraction (EF) were assessed during the growing season. Results indicated that both GPP and R eco linearly decreased with declining SWC, with the sensitivity of GPP to SWC being 3.8 times higher than that of R eco during the entire growing season. As a result, ecosystem CO 2 sequestration capacity decreased from 4.00μmolm -2 s -1 to 1.00μmolm -2 s -1 , with increasing soil drought . On a seasonal scale, significant correlation between GPP and SWC was only found in spring while that between R eco and SWC was found in all growing seasons with the sensitivity increasing steadily from spring to autumn. EF had a low correlation with SWC, GPP and R eco (R 2 =0.03, 0.02, 0.05, respectively), indicating that EF was not a good proxy for soil drought and energy partitioning was not tightly coupled to ecosystem carbon exchanges in this desert ecosystem. The study deepens our knowledge of ecosystem carbon exchange and its response to drought as well as its coupling with ecosystem energy partitioning in an extreme dry desert. The information is critical for better assessing carbon sequestration capacity in dryland, and for understanding its feedback to climate change. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Possibilistic Fuzzy Net Present Value Model and Application

    Directory of Open Access Journals (Sweden)

    S. S. Appadoo

    2014-01-01

    Full Text Available The cash flow values and the interest rate in the net present value (NPV model are usually specified by either crisp numbers or random variables. In this paper, we first discuss some of the recent developments in possibility theory and find closed form expressions for fuzzy possibilistic net present value (FNPV. Then, following Carlsson and Fullér (2001, we discuss some of the possibilistic moments related to FNPV model along with an illustrative numerical example. We also give a unified approach to find higher order moments of FNPV by using the moment generating function introduced by Paseka et al. (2011.

  3. Towards a Standard for Modular Petri Nets

    DEFF Research Database (Denmark)

    Kindler, Ekkart; Petrucci, Laure

    2009-01-01

    concepts could or should be subject to import and export in high-level Petri nets. In this paper, we formalise a minimal version of modular high-level Petri nets, which is based on the concepts of modular PNML. This shows that modular PNML can be formalised once a specific version of Petri net is fixed....... Moreover, we present and discuss some more advanced features of modular Petri nets that could be included in the standard. This way, we provide a formal foundation and a basis for a discussion of features to be included in the upcoming standard of a module concept for Petri nets in general and for high-level...

  4. Neural net prediction of tokamak plasma disruptions

    International Nuclear Information System (INIS)

    Hernandez, J.V.; Lin, Z.; Horton, W.; McCool, S.C.

    1994-10-01

    The computation based on neural net algorithms in predicting minor and major disruptions in TEXT tokamak discharges has been performed. Future values of the fluctuating magnetic signal are predicted based on L past values of the magnetic fluctuation signal, measured by a single Mirnov coil. The time step used (= 0.04ms) corresponds to the experimental data sampling rate. Two kinds of approaches are adopted for the task, the contiguous future prediction and the multi-timescale prediction. Results are shown for comparison. Both networks are trained through the back-propagation algorithm with inertial terms. The degree of this success indicates that the magnetic fluctuations associated with tokamak disruptions may be characterized by a relatively low-dimensional dynamical system

  5. Hindcasting and Forecasting of Surface Flow Fields through Assimilating High Frequency Remotely Sensing Radar Data

    Directory of Open Access Journals (Sweden)

    Lei Ren

    2017-09-01

    Full Text Available In order to improve the forecasting ability of numerical models, a sequential data assimilation scheme, nudging, was applied to blend remotely sensing high-frequency (HF radar surface currents with results from a three-dimensional numerical, EFDC (Environmental Fluid Dynamics Code model. For the first time, this research presents the most appropriate nudging parameters, which were determined from sensitivity experiments. To examine the influence of data assimilation cycle lengths on forecasts and to extend forecasting improvements, the duration of data assimilation cycles was studied through assimilating linearly interpolated temporal radar data. Data assimilation nudging parameters have not been previously analyzed. Assimilation of HF radar measurements at each model computational timestep outperformed those assimilation models using longer data assimilation cycle lengths; root-mean-square error (RMSE values of both surface velocity components during a 12 h model forecasting period indicated that surface flow fields were significantly improved when implementing nudging assimilation at each model computational timestep. The Data Assimilation Skill Score (DASS technique was used to quantitatively evaluate forecast improvements. The averaged values of DASS over the data assimilation domain were 26% and 33% for east–west and north–south velocity components, respectively, over the half-day forecasting period. Correlation of Averaged Kinetic Energy (AKE was improved by more than 10% in the best data assimilation model. Time series of velocity components and surface flow fields were presented to illustrate the improvement resulting from data assimilation application over time.

  6. Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data

    International Nuclear Information System (INIS)

    B. Faybishenko

    2006-01-01

    At Yucca Mountain, Nevada, future changes in climatic conditions will most likely alter net infiltration, or the drainage below the bottom of the evapotranspiration zone within the soil profile or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this paper are to: (a) develop a semi-empirical model and forecast average net infiltration rates, using the limited meteorological data from analogue meteorological stations, for interglacial (present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region, and (b) corroborate the computed net-infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. In this paper, the author presents an approach for calculations of net infiltration, aridity, and precipitation-effectiveness indices, using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman (1948) formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. For example, the mean glacial net-infiltration rate corresponds to the upper-bound glacial transition net infiltration, and the lower-bound glacial net infiltration corresponds to the glacial transition mean net infiltration. Forecasting of net infiltration for different climate states is subject to numerous uncertainties-associated with selecting climate analogue sites, using relatively short analogue meteorological records, neglecting the effects of vegetation and surface runoff and runon on a local scale, as well as possible anthropogenic climate changes

  7. Effect of multi-effect triazole on absorption of phosphorus and nitrogen and distribution of 14CO2-assimilates in rape plant

    International Nuclear Information System (INIS)

    Xi Haifu; Ye Qingfu; Shen Huicong; Zhou Weijun

    1995-01-01

    By using tracer technique, the effects of Multi-Effect Triazole (MET) on uptake of 32 P, 15 N and distribution of 14 CO 2 -assimilates in rape plant were studied. The experimental results showed that the foliar spraying of MET with the concentration of 150 ppm in three leaves stage could significantly increase 32 P uptake by 75.34%∼101.08%, the utilization rate of base fertilizer 15 NH 4 HCO 3 by 9.10%. And the rate of photosynthesis increased by 7.44%∼31.40% in seedling stage, by 47.74% in initial flowering stage and by 47.93% in mature stage. The regulation effects of MET on distribution of 15 N absorbed and 14 CO 2 -assimilates were shown by increasing absorption of 15 N and assimilates in seeds of rape plant

  8. Net metering in British Columbia : white paper

    International Nuclear Information System (INIS)

    Berry, T.

    2003-01-01

    Net metering was described as being the reverse registration of an electricity customer's revenue meter when interconnected with a utility's grid. It is a provincial policy designed to encourage small-distributed renewable power generation such as micro-hydro, solar energy, fuel cells, and larger-scale wind energy. It was noted that interconnection standards for small generation is an important issue that must be addressed. The British Columbia Utilities Commission has asked BC Hydro to prepare a report on the merits of net metering in order to support consultations on a potential net metering tariff application by the utility. This report provides information on net metering with reference to experience in other jurisdictions with net metering, and the possible costs and benefits associated with net metering from both a utility and consumer perspective. Some of the barriers and policy considerations for successful implementation of net metering were also discussed. refs., tabs., figs

  9. Flux balance analysis of ammonia assimilation network in E. coli predicts preferred regulation point.

    Science.gov (United States)

    Wang, Lu; Lai, Luhua; Ouyang, Qi; Tang, Chao

    2011-01-25

    Nitrogen assimilation is a critical biological process for the synthesis of biomolecules in Escherichia coli. The central ammonium assimilation network in E. coli converts carbon skeleton α-ketoglutarate and ammonium into glutamate and glutamine, which further serve as nitrogen donors for nitrogen metabolism in the cell. This reaction network involves three enzymes: glutamate dehydrogenase (GDH), glutamine synthetase (GS) and glutamate synthase (GOGAT). In minimal media, E. coli tries to maintain an optimal growth rate by regulating the activity of the enzymes to match the availability of the external ammonia. The molecular mechanism and the strategy of the regulation in this network have been the research topics for many investigators. In this paper, we develop a flux balance model for the nitrogen metabolism, taking into account of the cellular composition and biosynthetic requirements for nitrogen. The model agrees well with known experimental results. Specifically, it reproduces all the (15)N isotope labeling experiments in the wild type and the two mutant (ΔGDH and ΔGOGAT) strains of E. coli. Furthermore, the predicted catalytic activities of GDH, GS and GOGAT in different ammonium concentrations and growth rates for the wild type, ΔGDH and ΔGOGAT strains agree well with the enzyme concentrations obtained from western blots. Based on this flux balance model, we show that GS is the preferred regulation point among the three enzymes in the nitrogen assimilation network. Our analysis reveals the pattern of regulation in this central and highly regulated network, thus providing insights into the regulation strategy adopted by the bacteria. Our model and methods may also be useful in future investigations in this and other networks.

  10. Acetate and bicarbonate assimilation and metabolite formation in Chlamydomonas reinhardtii: a 13C-NMR study.

    Directory of Open Access Journals (Sweden)

    Himanshu Singh

    Full Text Available Cellular metabolite analyses by (13C-NMR showed that C. reinhardtii cells assimilate acetate at a faster rate in heterotrophy than in mixotrophy. While heterotrophic cells produced bicarbonate and CO2aq, mixotrophy cells produced bicarbonate alone as predominant metabolite. Experiments with singly (13C-labelled acetate ((13CH(3-COOH or CH(3-(13COOH supported that both the (13C nuclei give rise to bicarbonate and CO2(aq. The observed metabolite(s upon further incubation led to the production of starch and triacylglycerol (TAG in mixotrophy, whereas in heterotrophy the TAG production was minimal with substantial accumulation of glycerol and starch. Prolonged incubation up to eight days, without the addition of fresh acetate, led to an increased TAG production at the expense of bicarbonate, akin to that of nitrogen-starvation. However, such TAG production was substantially high in mixotrophy as compared to that in heterotrophy. Addition of mitochondrial un-coupler blocked the formation of bicarbonate and CO2(aq in heterotrophic cells, even though acetate uptake ensued. Addition of PSII-inhibitor to mixotrophic cells resulted in partial conversion of bicarbonate into CO2(aq, which were found to be in equilibrium. In an independent experiment, we have monitored assimilation of bicarbonate via photoautotrophy and found that the cells indeed produce starch and TAG at a much faster rate as compared to that in mixotrophy and heterotrophy. Further, we noticed that the accumulation of starch is relatively more as compared to TAG. Based on these observations, we suggest that acetate assimilation in C. reinhardtii does not directly lead to TAG formation but via bicarbonate/CO2(aq pathways. Photoautotrophic mode is found to be the best growth condition for the production of starch and TAG and starch in C. reinhardtii.

  11. Flux balance analysis of ammonia assimilation network in E. coli predicts preferred regulation point.

    Directory of Open Access Journals (Sweden)

    Lu Wang

    Full Text Available Nitrogen assimilation is a critical biological process for the synthesis of biomolecules in Escherichia coli. The central ammonium assimilation network in E. coli converts carbon skeleton α-ketoglutarate and ammonium into glutamate and glutamine, which further serve as nitrogen donors for nitrogen metabolism in the cell. This reaction network involves three enzymes: glutamate dehydrogenase (GDH, glutamine synthetase (GS and glutamate synthase (GOGAT. In minimal media, E. coli tries to maintain an optimal growth rate by regulating the activity of the enzymes to match the availability of the external ammonia. The molecular mechanism and the strategy of the regulation in this network have been the research topics for many investigators. In this paper, we develop a flux balance model for the nitrogen metabolism, taking into account of the cellular composition and biosynthetic requirements for nitrogen. The model agrees well with known experimental results. Specifically, it reproduces all the (15N isotope labeling experiments in the wild type and the two mutant (ΔGDH and ΔGOGAT strains of E. coli. Furthermore, the predicted catalytic activities of GDH, GS and GOGAT in different ammonium concentrations and growth rates for the wild type, ΔGDH and ΔGOGAT strains agree well with the enzyme concentrations obtained from western blots. Based on this flux balance model, we show that GS is the preferred regulation point among the three enzymes in the nitrogen assimilation network. Our analysis reveals the pattern of regulation in this central and highly regulated network, thus providing insights into the regulation strategy adopted by the bacteria. Our model and methods may also be useful in future investigations in this and other networks.

  12. Carbon cycling of European croplands: A framework for the assimilation of optical and microwave Earth observation data

    Science.gov (United States)

    Revill, Andrew; Sus, Oliver; Williams, Mathew

    2013-04-01

    Croplands are traditionally managed to maximise the production of food, feed, fibre and bioenergy. Advancements in agricultural technologies, together with land-use change, have approximately doubled World grain harvests over the past 50 years. Cropland ecosystems also play a significant role in the global carbon (C) cycle and, through changes to C storage in response to management activities, they can provide opportunities for climate change mitigation. However, quantifying and understanding the cropland C cycle is complex, due to variable environmental drivers, varied management practices and often highly heterogeneous landscapes. Efforts to upscale processes using simulation models must resolve these challenges. Here we show how data assimilation (DA) approaches can link C cycle modelling to Earth observation (EO) and reduce uncertainty in upscaling. We evaluate a framework for the assimilation of leaf area index (LAI) time series, empirically derived from EO optical and radar sensors, for state-updating a model of crop development and C fluxes. Sensors are selected with fine spatial resolutions (20-50 m) to resolve variability across field sizes typically used in European agriculture. Sequential DA is used to improve the canopy development simulation, which is validated by comparing time-series LAI and net ecosystem exchange (NEE) predictions to independent ground measurements and eddy covariance observations at multiple European cereal crop sites. Significant empirical relationships were established between the LAI ground measurements and the optical reflectance and radar backscatter, which allowed for single LAI calibrations being valid for all the cropland sites for each sensor. The DA of all EO LAI estimates results indicated clear adjustments in LAI and an enhanced representation of daily CO2 exchanges, particularly around the time of peak C uptake. Compared to the simulation without DA, the assimilation of all EO LAI estimates improved the predicted at

  13. Gastrointestinal assimilation of Cu during digestion of a single meal in the freshwater rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Nadella, Sunita R; Bucking, Carol; Grosell, Martin; Wood, Chris M

    2006-08-01

    Gastrointestinal processing and assimilation of Cu in vivo was investigated by sequential chyme analysis over a 72 h period following ingestion of a single satiation meal (3% body weight) of commercial trout food (Cu content=0.42 micromol g(-1)) by adult rainbow trout. Leaded glass ballotini beads incorporated into the food and detected by X-ray radiography were employed as an inert marker in order to quantify net Cu absorption or secretion in various parts of the tract. Cu concentrations in the supernatant (fluid phase) fell from about 0.06 micromol mL(-1) (63 microM) in the stomach at 2 h to about 0.003 micromol mL(-1) (3 microM) in the posterior intestine at 72 h. Cu concentrations in the solid phase were 10 to 30-fold higher than in the fluid phase, and increased about 4-fold from the stomach at 2 h to the posterior intestine at 72 h. By reference to the inert marker, overall net Cu absorption from the ingested food by 72 h was about 50%. The mid-intestine, and posterior intestine emerged as important sites of net Cu and water absorption and a potential role for the stomach in this process was also indicated. The anterior intestine was a site of large net Cu addition to the chyme, probably due to large net additions of Cu-containing fluids in the form of bile and other secretions in this segment. The results provide valuable information about sites of Cu absorption and realistic concentrations of Cu in chyme fluid for future in vitro mechanistic studies on Cu transport in the trout gastrointestinal tract.

  14. Pro-Nets versus No-Nets: Differences in Urban Older Adults' Predilections for Internet Use

    Science.gov (United States)

    Cresci, M. Kay; Yarandi, Hossein N.; Morrell, Roger W.

    2010-01-01

    Enthusiasm for information technology (IT) is growing among older adults. Many older adults enjoy IT and the Internet (Pro-Nets), but others have no desire to use it (No-Nets). This study found that Pro-Nets and No-Nets were different on a number of variables that might predict IT use. No-Nets were older, had less education and income, were…

  15. Risk assessment for invasive species produces net bioeconomic benefits.

    Science.gov (United States)

    Keller, Reuben P; Lodge, David M; Finnoff, David C

    2007-01-02

    International commerce in live organisms presents a policy challenge for trade globalization; sales of live organisms create wealth, but some nonindigenous species cause harm. To reduce damage, some countries have implemented species screening to limit the introduction of damaging species. Adoption of new risk assessment (RA) technologies has been slowed, however, by concerns that RA accuracy remains insufficient to produce positive net economic benefits. This concern arises because only a small proportion of all introduced species escape, spread, and cause harm (i.e., become invasive), so a RA will exclude many noninvasive species (which provide a net economic benefit) for every invasive species correctly identified. Here, we develop a simple cost:benefit bioeconomic framework to quantify the net benefits from applying species prescreening. Because invasive species are rarely eradicated, and their damages must therefore be borne for long periods, we have projected the value of RA over a suitable range of policy time horizons (10-500 years). We apply the model to the Australian plant quarantine program and show that this RA program produces positive net economic benefits over the range of reasonable assumptions. Because we use low estimates of the financial damage caused by invasive species and high estimates of the value of species in the ornamental trade, our results underestimate the net benefit of the Australian plant quarantine program. In addition, because plants have relatively low rates of invasion, applying screening protocols to animals would likely demonstrate even greater benefits.

  16. [Simulating of carbon fluxes in bamboo forest ecosystem using BEPS model based on the LAI assimilated with Dual Ensemble Kalman Filter].

    Science.gov (United States)

    Li, Xue Jian; Mao, Fang Jie; Du, Hua Qiang; Zhou, Guo Mo; Xu, Xiao Jun; Li, Ping Heng; Liu, Yu Li; Cui, Lu

    2016-12-01

    LAI is one of the most important observation data in the research of carbon cycle of forest ecosystem, and it is also an important parameter to drive process-based ecosystem model. The Moso bamboo forest (MBF) and Lei bamboo forest (LBF) were selected as the study targets. Firstly, the MODIS LAI time series data during 2014-2015 was assimilated with Dual Ensemble Kalman Filter method. Secondly, the high quality assimilated MBF LAI and LBF LAI were used as input dataset to drive BEPS model for simulating the gross primary productivity (GPP), net ecosystem exchange (NEE) and total ecosystem respiration (TER) of the two types of bamboo forest ecosystem, respectively. The modeled carbon fluxes were evaluated by the observed carbon fluxes data, and the effects of different quality LAI inputs on carbon cycle simulation were also studied. The LAI assimilated using Dual Ensemble Kalman Filter of MBF and LBF were significantly correlated with the observed LAI, with high R 2 of 0.81 and 0.91 respectively, and lower RMSE and absolute bias, which represented the great improvement of the accuracy of MODIS LAI products. With the driving of assimilated LAI, the modeled GPP, NEE, and TER were also highly correlated with the flux observation data, with the R 2 of 0.66, 0.47, and 0.64 for MBF, respectively, and 0.66, 0.45, and 0.73 for LBF, respectively. The accuracy of carbon fluxes modeled with assimilated LAI was higher than that acquired by the locally adjusted cubic-spline capping method, in which, the accuracy of mo-deled NEE for MBF and LBF increased by 11.2% and 11.8% at the most degrees, respectively.

  17. Effects of Model Chemistry and Data Biases on Stratospheric Ozone Assimilation

    National Research Council Canada - National Science Library

    Coy, L; Allen, D. R; Eckermann, S. D; McCormack, J. P; Stajner, I; Hogan, T. F

    2007-01-01

    .... In this study, O-F statistics from the Global Ozone Assimilation Testing System (GOATS) are used to examine how ozone assimilation products and their associated O-F statistics depend on input data biases and ozone photochemistry parameterizations (OPP...

  18. Sensitivity of Satellite Altimetry Data Assimilation on a Weapon Acoustic Preset Using MODAS

    National Research Council Canada - National Science Library

    Chu, Peter; Mancini, Steven; Gottshall, Eric; Cwalina, David; Barron, Charlie N

    2007-01-01

    ...) is analyzed with SSP derived from the modular ocean data assimilation system (MODAS). The MODAS fields differ in that one uses altimeter data assimilated from three satellites while the other uses no altimeter data...

  19. Sucrose assimilation and the role of sucrose transporters in plant ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-29

    Dec 29, 2008 ... African Journal of Biotechnology Vol. 7 (25), pp. ... Review. Sucrose assimilation and the role of sucrose transporters in plant wound response. Omodele ... Key words: Sucrose transporters, Plasma membrane, carbohydrate, sieve element, source-sink. ... pathogens (Paul et al., 2000) and results in a severe.

  20. Economic Assimilation and Outmigration of Immigrants in West-Germany

    NARCIS (Netherlands)

    Bellemare, C.

    2003-01-01

    By analyzing earnings of observed immigrants workers, the literature on the economic assimilation of immigrants has generally overlooked two potentially important selectivity issues.First, earnings of immigrant workers may di¿er substantially from those of non-workers.Second, earnings of immigrants

  1. Opinion Dynamics with Heterogeneous Interactions and Information Assimilation

    Science.gov (United States)

    Mir Tabatabaei, Seydeh Anahita

    2013-01-01

    In any modern society, individuals interact to form opinions on various topics, including economic, political, and social aspects. Opinions evolve as the result of the continuous exchange of information among individuals and of the assimilation of information distributed by media. The impact of individuals' opinions on each other forms a network,…

  2. Anterior Cingulate Cortex in Schema Assimilation and Expression

    Science.gov (United States)

    Wang, Szu-Han; Tse, Dorothy; Morris, Richard G. M.

    2012-01-01

    In humans and in animals, mental schemas can store information within an associative framework that enables rapid and efficient assimilation of new information. Using a hippocampal-dependent paired-associate task, we now report that the anterior cingulate cortex is part of a neocortical network of schema storage with NMDA receptor-mediated…

  3. Volcanic Ash Data Assimilation System for Atmospheric Transport Model

    Science.gov (United States)

    Ishii, K.; Shimbori, T.; Sato, E.; Tokumoto, T.; Hayashi, Y.; Hashimoto, A.

    2017-12-01

    The Japan Meteorological Agency (JMA) has two operations for volcanic ash forecasts, which are Volcanic Ash Fall Forecast (VAFF) and Volcanic Ash Advisory (VAA). In these operations, the forecasts are calculated by atmospheric transport models including the advection process, the turbulent diffusion process, the gravitational fall process and the deposition process (wet/dry). The initial distribution of volcanic ash in the models is the most important but uncertain factor. In operations, the model of Suzuki (1983) with many empirical assumptions is adopted to the initial distribution. This adversely affects the reconstruction of actual eruption plumes.We are developing a volcanic ash data assimilation system using weather radars and meteorological satellite observation, in order to improve the initial distribution of the atmospheric transport models. Our data assimilation system is based on the three-dimensional variational data assimilation method (3D-Var). Analysis variables are ash concentration and size distribution parameters which are mutually independent. The radar observation is expected to provide three-dimensional parameters such as ash concentration and parameters of ash particle size distribution. On the other hand, the satellite observation is anticipated to provide two-dimensional parameters of ash clouds such as mass loading, top height and particle effective radius. In this study, we estimate the thickness of ash clouds using vertical wind shear of JMA numerical weather prediction, and apply for the volcanic ash data assimilation system.

  4. A reduced adjoint approach to variational data assimilation

    KAUST Repository

    Altaf, Muhammad; El Gharamti, Mohamad; Heemink, Arnold W.; Hoteit, Ibrahim

    2013-01-01

    The adjoint method has been used very often for variational data assimilation. The computational cost to run the adjoint model often exceeds several original model runs and the method needs significant programming efforts to implement the adjoint model code. The work proposed here is variational data assimilation based on proper orthogonal decomposition (POD) which avoids the implementation of the adjoint of the tangent linear approximation of the original nonlinear model. An ensemble of the forward model simulations is used to determine the approximation of the covariance matrix and only the dominant eigenvectors of this matrix are used to define a model subspace. The adjoint of the tangent linear model is replaced by the reduced adjoint based on this reduced space. Thus the adjoint model is run in reduced space with negligible computational cost. Once the gradient is obtained in reduced space it is projected back in full space and the minimization process is carried in full space. In the paper the reduced adjoint approach to variational data assimilation is introduced. The characteristics and performance of the method are illustrated with a number of data assimilation experiments in a ground water subsurface contaminant model. © 2012 Elsevier B.V.

  5. A reduced adjoint approach to variational data assimilation

    KAUST Repository

    Altaf, Muhammad

    2013-02-01

    The adjoint method has been used very often for variational data assimilation. The computational cost to run the adjoint model often exceeds several original model runs and the method needs significant programming efforts to implement the adjoint model code. The work proposed here is variational data assimilation based on proper orthogonal decomposition (POD) which avoids the implementation of the adjoint of the tangent linear approximation of the original nonlinear model. An ensemble of the forward model simulations is used to determine the approximation of the covariance matrix and only the dominant eigenvectors of this matrix are used to define a model subspace. The adjoint of the tangent linear model is replaced by the reduced adjoint based on this reduced space. Thus the adjoint model is run in reduced space with negligible computational cost. Once the gradient is obtained in reduced space it is projected back in full space and the minimization process is carried in full space. In the paper the reduced adjoint approach to variational data assimilation is introduced. The characteristics and performance of the method are illustrated with a number of data assimilation experiments in a ground water subsurface contaminant model. © 2012 Elsevier B.V.

  6. Music playlist generation by assimilating GMMs into SOMs

    NARCIS (Netherlands)

    Balkema, Wietse; van der Heijden, Ferdinand

    A method for music playlist generation, using assimilated Gaussian mixture models (GMMs) in self organizing maps (SOMs) is presented. Traditionally, the neurons in a SOM are represented by vectors, but in this paper we propose to use GMMs instead. To this end, we introduce a method to adapt a GMM

  7. Growth, assimilate partitioning and grain yield response of soybean ...

    African Journals Online (AJOL)

    This investigation tested variation in the growth components, assimilate partitioning and grain yield of soybean (Glycine max L. Merrrill) varieties established in CO2 enriched atmosphere when inoculated with mixtures of Arbuscular mycorrhizal fungi (AMF) species in the humid rainforest of Nigeria. A pot and a field ...

  8. Homophily and assimilation among sportactive adolescent substance users

    NARCIS (Netherlands)

    Pearson, M; Steglich, Ch.; Snijders, T.A.B.

    2006-01-01

    We analyse the co-evolution of social networks and substance use behaviour of adolescents and address the problem of separating the effects of homophily and assimilation. Adolescents who prefer friends with the same substance-use behaviour exhibit the homophily principle. Adolescents who adapt their

  9. Modelling Effluent Assimilative Capacity of Ikpoba River, Benin City ...

    African Journals Online (AJOL)

    The sheer display of reprehensible propensity on the part of public hospitals, abattoirs, breweries and city dwellers at large to discharge untreated waste, debris, scum and, in particular, municipal and industrial effluents into Ikpoba River has morphed into a situation whereby the assimilative capacity of the river has reached ...

  10. Satellite Data Assimilation within KIAPS-LETKF system

    Science.gov (United States)

    Jo, Y.; Lee, S., Sr.; Cho, K.

    2016-12-01

    Korea Institute of Atmospheric Prediction Systems (KIAPS) has been developing an ensemble data assimilation system using four-dimensional local ensemble transform kalman filter (LETKF; Hunt et al., 2007) within KIAPS Integrated Model (KIM), referred to as "KIAPS-LETKF". KIAPS-LETKF system was successfully evaluated with various Observing System Simulation Experiments (OSSEs) with NCAR Community Atmospheric Model - Spectral Element (Kang et al., 2013), which has fully unstructured quadrilateral meshes based on the cubed-sphere grid as the same grid system of KIM. Recently, assimilation of real observations has been conducted within the KIAPS-LETKF system with four-dimensional covariance functions over the 6-hr assimilation window. Then, conventional (e.g., sonde, aircraft, and surface) and satellite (e.g., AMSU-A, IASI, GPS-RO, and AMV) observations have been provided by the KIAPS Package for Observation Processing (KPOP). Wind speed prediction was found most beneficial due to ingestion of AMV and for the temperature prediction the improvement in assimilation is mostly due to ingestion of AMSU-A and IASI. However, some degradation in the simulation of the GPS-RO is presented in the upper stratosphere, even though GPS-RO leads positive impacts on the analysis and forecasts. We plan to test the bias correction method and several vertical localization strategies for radiance observations to improve analysis and forecast impacts.

  11. Assimilation of Long-Range Lightning Data over the Pacific

    Science.gov (United States)

    2011-09-30

    convective rainfall analyses over the Pacific, and (iii) to improve marine prediction of cyclogenesis of both tropical and extratropical cyclones through...data over the North Pacific Ocean, refine the relationships between lightning and storm hydrometeor characteristics, and assimilate lightning...unresolved storm -scale areas of deep convection over the data-sparse open oceans. Diabatic heating sources, especially latent heat release in deep

  12. Abscisic acid and assimilate partitioning during seed development

    NARCIS (Netherlands)

    Bruijn, de S.M.

    1993-01-01

    This thesis describes the influence of abscisic acid (ABA) on the transport of assimilates to seeds and the deposition of reserves in seeds. It is well-known from literature that ABA accumulates in seeds during development, and that ABA concentrations in seeds correlate rather well with

  13. A Generic Software Framework for Data Assimilation and Model Calibration

    NARCIS (Netherlands)

    Van Velzen, N.

    2010-01-01

    The accuracy of dynamic simulation models can be increased by using observations in conjunction with a data assimilation or model calibration algorithm. However, implementing such algorithms usually increases the complexity of the model software significantly. By using concepts from object oriented

  14. Educational Attainments of Immigrant Offspring: Success or Segmented Assimilation?

    Science.gov (United States)

    Boyd, Monica

    2002-01-01

    Examined the educational attainments of adult offspring of immigrants age 20-64 years, analyzing data from Canada's 1996 Survey of Labour and Income Dynamics. Contrary to second generation decline and segmented underclass assimilation found in the United States, Canadian adult visible-minority immigrant offspring did not have lower educational…

  15. Global assimilation of X Project Loon stratospheric balloon observations

    Science.gov (United States)

    Coy, L.; Schoeberl, M. R.; Pawson, S.; Candido, S.; Carver, R. W.

    2017-12-01

    Project Loon has an overall goal of providing worldwide internet coverage using a network of long-duration super-pressure balloons. Beginning in 2013, Loon has launched over 1600 balloons from multiple tropical and middle latitude locations. These GPS tracked balloon trajectories provide lower stratospheric wind information over the oceans and remote land areas where traditional radiosonde soundings are sparse, thus providing unique coverage of lower stratospheric winds. To fully investigate these Loon winds we: 1) compare the Loon winds to winds produced by a global data assimilation system (DAS: NASA GEOS) and 2) assimilate the Loon winds into the same comprehensive DAS. Results show that in middle latitudes the Loon winds and DAS winds agree well and assimilating the Loon winds have only a small impact on short-term forecasting of the Loon winds, however, in the tropics the loon winds and DAS winds often disagree substantially (8 m/s or more in magnitude) and in these cases assimilating the loon winds significantly improves the forecast of the loon winds. By highlighting cases where the Loon and DAS winds differ, these results can lead to improved understanding of stratospheric winds, especially in the tropics.

  16. Carbon assimilation and transfer through kelp forests in the NE Atlantic is diminished under a warmer ocean climate.

    Science.gov (United States)

    Pessarrodona, Albert; Moore, Pippa J; Sayer, Martin D J; Smale, Dan A

    2018-06-03

    Global climate change is affecting carbon cycling by driving changes in primary productivity and rates of carbon fixation, release and storage within Earth's vegetated systems. There is, however, limited understanding of how carbon flow between donor and recipient habitats will respond to climatic changes. Macroalgal-dominated habitats, such as kelp forests, are gaining recognition as important carbon donors within coastal carbon cycles, yet rates of carbon assimilation and transfer through these habitats are poorly resolved. Here, we investigated the likely impacts of ocean warming on coastal carbon cycling by quantifying rates of carbon assimilation and transfer in Laminaria hyperborea kelp forests-one of the most extensive coastal vegetated habitat types in the NE Atlantic-along a latitudinal temperature gradient. Kelp forests within warm climatic regimes assimilated, on average, more than three times less carbon and donated less than half the amount of particulate carbon compared to those from cold regimes. These patterns were not related to variability in other environmental parameters. Across their wider geographical distribution, plants exhibited reduced sizes toward their warm-water equatorward range edge, further suggesting that carbon flow is reduced under warmer climates. Overall, we estimated that Laminaria hyperborea forests stored ~11.49 Tg C in living biomass and released particulate carbon at a rate of ~5.71 Tg C year -1 . This estimated flow of carbon was markedly higher than reported values for most other marine and terrestrial vegetated habitat types in Europe. Together, our observations suggest that continued warming will diminish the amount of carbon that is assimilated and transported through temperate kelp forests in NE Atlantic, with potential consequences for the coastal carbon cycle. Our findings underline the need to consider climate-driven changes in the capacity of ecosystems to fix and donate carbon when assessing the impacts of

  17. The re-assimilation of ammonia produced by photorespiration and the nitrogen economy of C3 higher plants.

    Science.gov (United States)

    Keys, Alfred J

    2006-02-01

    Photorespiration involves the conversion of glycine to serine with the release of ammonia and CO(2). In C(3) terrestrial higher plants the flux through glycine and serine is so large that it results in the production of ammonia at a rate far exceeding that from reduction of new nitrogen entering the plant. The photorespiratory nitrogen cycle re-assimilates this ammonia using the enzymes glutamine synthetase and glutamine:2-oxoglutarateaminotransferase.

  18. A data assimilation framework for constraining upscaled cropland carbon flux seasonality and biometry with MODIS

    Directory of Open Access Journals (Sweden)

    O. Sus

    2013-04-01

    Full Text Available Agroecosystem models are strongly dependent on information on land management patterns for regional applications. Land management practices play a major role in determining global yield variability, and add an anthropogenic signal to the observed seasonality of atmospheric CO2 concentrations. However, there is still little knowledge on spatial and temporal variability of important farmland activities such as crop sowing dates, and thus these remain rather crudely approximated within carbon cycle studies. In this study, we present a framework allowing for spatio-temporally resolved simulation of cropland carbon fluxes under observational constraints on land management and canopy greenness. We apply data assimilation methodology in order to explicitly account for information on sowing dates and model leaf area index. MODIS 250 m vegetation index data were assimilated both in batch-calibration for sowing date estimation and sequentially for improved model state estimation, using the ensemble Kalman filter (EnKF, into a crop carbon mass balance model (SPAc. In doing so, we are able to quantify the multiannual (2000–2006 regional carbon flux and biometry seasonality of maize–soybean crop rotations surrounding the Bondville Ameriflux eddy covariance site, averaged over 104 pixel locations within the wider area. (1 Validation at the Bondville site shows that growing season C cycling is simulated accurately with MODIS-derived sowing dates, and we expect that this framework allows for accurate simulations of C cycling at locations for which ground-truth data are not available. Thus, this framework enables modellers to simulate current (i.e. last 10 yr carbon cycling of major agricultural regions. Averaged over the 104 field patches analysed, relative spatial variability for biometry and net ecosystem exchange ranges from ∼7% to ∼18%. The annual sign of net biome productivity is not significantly different from carbon neutrality. (2 Moreover

  19. Lidar data assimilation for improved analyses of volcanic aerosol events

    Science.gov (United States)

    Lange, Anne Caroline; Elbern, Hendrik

    2014-05-01

    Observations of hazardous events with release of aerosols are hardly analyzable by today's data assimilation algorithms, without producing an attenuating bias. Skillful forecasts of unexpected aerosol events are essential for human health and to prevent an exposure of infirm persons and aircraft with possibly catastrophic outcome. Typical cases include mineral dust outbreaks, mostly from large desert regions, wild fires, and sea salt uplifts, while the focus aims for volcanic eruptions. In general, numerical chemistry and aerosol transport models cannot simulate such events without manual adjustments. The concept of data assimilation is able to correct the analysis, as long it is operationally implemented in the model system. Though, the tangent-linear approximation, which describes a substantial precondition for today's cutting edge data assimilation algorithms, is not valid during unexpected aerosol events. As part of the European COPERNICUS (earth observation) project MACC II and the national ESKP (Earth System Knowledge Platform) initiative, we developed a module that enables the assimilation of aerosol lidar observations, even during unforeseeable incidences of extreme emissions of particulate matter. Thereby, the influence of the background information has to be reduced adequately. Advanced lidar instruments comprise on the one hand the aspect of radiative transfer within the atmosphere and on the other hand they can deliver a detailed quantification of the detected aerosols. For the assimilation of maximal exploited lidar data, an appropriate lidar observation operator is constructed, compatible with the EURAD-IM (European Air Pollution and Dispersion - Inverse Model) system. The observation operator is able to map the modeled chemical and physical state on lidar attenuated backscatter, transmission, aerosol optical depth, as well as on the extinction and backscatter coefficients. Further, it has the ability to process the observed discrepancies with lidar

  20. Data Assimilation to Extract Soil Moisture Information from SMAP Observations

    Directory of Open Access Journals (Sweden)

    Jana Kolassa

    2017-11-01

    Full Text Available This study compares different methods to extract soil moisture information through the assimilation of Soil Moisture Active Passive (SMAP observations. Neural network (NN and physically-based SMAP soil moisture retrievals were assimilated into the National Aeronautics and Space Administration (NASA Catchment model over the contiguous United States for April 2015 to March 2017. By construction, the NN retrievals are consistent with the global climatology of the Catchment model soil moisture. Assimilating the NN retrievals without further bias correction improved the surface and root zone correlations against in situ measurements from 14 SMAP core validation sites (CVS by 0.12 and 0.16, respectively, over the model-only skill, and reduced the surface and root zone unbiased root-mean-square error (ubRMSE by 0.005 m 3 m − 3 and 0.001 m 3 m − 3 , respectively. The assimilation reduced the average absolute surface bias against the CVS measurements by 0.009 m 3 m − 3 , but increased the root zone bias by 0.014 m 3 m − 3 . Assimilating the NN retrievals after a localized bias correction yielded slightly lower surface correlation and ubRMSE improvements, but generally the skill differences were small. The assimilation of the physically-based SMAP Level-2 passive soil moisture retrievals using a global bias correction yielded similar skill improvements, as did the direct assimilation of locally bias-corrected SMAP brightness temperatures within the SMAP Level-4 soil moisture algorithm. The results show that global bias correction methods may be able to extract more independent information from SMAP observations compared to local bias correction methods, but without accurate quality control and observation error characterization they are also more vulnerable to adverse effects from retrieval errors related to uncertainties in the retrieval inputs and algorithm. Furthermore, the results show that using global bias correction approaches without a

  1. Improving Forecast Skill by Assimilation of AIRS Temperature Soundings

    Science.gov (United States)

    Susskind, Joel; Reale, Oreste

    2010-01-01

    AIRS was launched on EOS Aqua on May 4, 2002, together with AMSU-A and HSB, to form a next generation polar orbiting infrared and microwave atmospheric sounding system. The primary products of AIRS/AMSU-A are twice daily global fields of atmospheric temperature-humidity profiles, ozone profiles, sea/land surface skin temperature, and cloud related parameters including OLR. The AIRS Version 5 retrieval algorithm, is now being used operationally at the Goddard DISC in the routine generation of geophysical parameters derived from AIRS/AMSU data. A major innovation in Version 5 is the ability to generate case-by-case level-by-level error estimates delta T(p) for retrieved quantities and the use of these error estimates for Quality Control. We conducted a number of data assimilation experiments using the NASA GEOS-5 Data Assimilation System as a step toward finding an optimum balance of spatial coverage and sounding accuracy with regard to improving forecast skill. The model was run at a horizontal resolution of 0.5 deg. latitude X 0.67 deg longitude with 72 vertical levels. These experiments were run during four different seasons, each using a different year. The AIRS temperature profiles were presented to the GEOS-5 analysis as rawinsonde profiles, and the profile error estimates delta (p) were used as the uncertainty for each measurement in the data assimilation process. We compared forecasts analyses generated from the analyses done by assimilation of AIRS temperature profiles with three different sets of thresholds; Standard, Medium, and Tight. Assimilation of Quality Controlled AIRS temperature profiles significantly improve 5-7 day forecast skill compared to that obtained without the benefit of AIRS data in all of the cases studied. In addition, assimilation of Quality Controlled AIRS temperature soundings performs better than assimilation of AIRS observed radiances. Based on the experiments shown, Tight Quality Control of AIRS temperature profile performs best

  2. Snow multivariable data assimilation for hydrological predictions in mountain areas

    Science.gov (United States)

    Piazzi, Gaia; Campo, Lorenzo; Gabellani, Simone; Rudari, Roberto; Castelli, Fabio; Cremonese, Edoardo; Morra di Cella, Umberto; Stevenin, Hervé; Ratto, Sara Maria

    2016-04-01

    The seasonal presence of snow on alpine catchments strongly impacts both surface energy balance and water resource. Thus, the knowledge of the snowpack dynamics is of critical importance for several applications, such as water resource management, floods prediction and hydroelectric power production. Several independent data sources provide information about snowpack state: ground-based measurements, satellite data and physical models. Although all these data types are reliable, each of them is affected by specific flaws and errors (respectively dependency on local conditions, sensor biases and limitations, initialization and poor quality forcing data). Moreover, there are physical factors that make an exhaustive reconstruction of snow dynamics complicated: snow intermittence in space and time, stratification and slow phenomena like metamorphism processes, uncertainty in snowfall evaluation, wind transportation, etc. Data Assimilation (DA) techniques provide an objective methodology to combine observational and modeled information to obtain the most likely estimate of snowpack state. Indeed, by combining all the available sources of information, the implementation of DA schemes can quantify and reduce the uncertainties of the estimations. This study presents SMASH (Snow Multidata Assimilation System for Hydrology), a multi-layer snow dynamic model, strengthened by a robust multivariable data assimilation algorithm. The model is physically based on mass and energy balances and can be used to reproduce the main physical processes occurring within the snowpack: accumulation, density dynamics, melting, sublimation, radiative balance, heat and mass exchanges. The model is driven by observed forcing meteorological data (air temperature, wind velocity, relative air humidity, precipitation and incident solar radiation) to provide a complete estimate of snowpack state. The implementation of an Ensemble Kalman Filter (EnKF) scheme enables to assimilate simultaneously ground

  3. Using Routine Data for Quality Assessment in NeuroNet Telestroke Care

    DEFF Research Database (Denmark)

    Theiss, Stephan; Günzel, Franziska; Storm, Anna

    2013-01-01

    : Routine clinical data from the HELIOS hospital information system were compared before and after implementation of the NeuroNet concept, including neurologic acute stroke teleconsultations, standard operating procedures, and peer review quality management in 3 hospital cohorts: 5 comprehensive stroke...... centers, 5 NeuroNet hospitals, and 5 matched control hospitals. RESULTS: During the study period, the rate of thrombolytic therapy increased by 4.8% in NeuroNet hospitals, while ischemic stroke in-hospital mortality decreased (relative risk reduction ∼29% in NeuroNet and control hospitals). The odds ratio...... for thrombolytic therapy in comprehensive stroke centers compared to NeuroNet hospitals was reduced from 3.7 to 1.3 between 2006 and 2009. Comprehensive stroke care coding according to German Diagnosis Related Groups definitions increased by 45% in NeuroNet (P

  4. Bound states in string nets

    Science.gov (United States)

    Schulz, Marc Daniel; Dusuel, Sébastien; Vidal, Julien

    2016-11-01

    We discuss the emergence of bound states in the low-energy spectrum of the string-net Hamiltonian in the presence of a string tension. In the ladder geometry, we show that a single bound state arises either for a finite tension or in the zero-tension limit depending on the theory considered. In the latter case, we perturbatively compute the binding energy as a function of the total quantum dimension. We also address this issue in the honeycomb lattice where the number of bound states in the topological phase depends on the total quantum dimension. Finally, the internal structure of these bound states is analyzed in the zero-tension limit.

  5. -Net Approach to Sensor -Coverage

    Directory of Open Access Journals (Sweden)

    Fusco Giordano

    2010-01-01

    Full Text Available Wireless sensors rely on battery power, and in many applications it is difficult or prohibitive to replace them. Hence, in order to prolongate the system's lifetime, some sensors can be kept inactive while others perform all the tasks. In this paper, we study the -coverage problem of activating the minimum number of sensors to ensure that every point in the area is covered by at least sensors. This ensures higher fault tolerance, robustness, and improves many operations, among which position detection and intrusion detection. The -coverage problem is trivially NP-complete, and hence we can only provide approximation algorithms. In this paper, we present an algorithm based on an extension of the classical -net technique. This method gives an -approximation, where is the number of sensors in an optimal solution. We do not make any particular assumption on the shape of the areas covered by each sensor, besides that they must be closed, connected, and without holes.

  6. The Net Reclassification Index (NRI)

    DEFF Research Database (Denmark)

    Pepe, Margaret S.; Fan, Jing; Feng, Ziding

    2015-01-01

    The Net Reclassification Index (NRI) is a very popular measure for evaluating the improvement in prediction performance gained by adding a marker to a set of baseline predictors. However, the statistical properties of this novel measure have not been explored in depth. We demonstrate the alarming...... result that the NRI statistic calculated on a large test dataset using risk models derived from a training set is likely to be positive even when the new marker has no predictive information. A related theoretical example is provided in which an incorrect risk function that includes an uninformative...... marker is proven to erroneously yield a positive NRI. Some insight into this phenomenon is provided. Since large values for the NRI statistic may simply be due to use of poorly fitting risk models, we suggest caution in using the NRI as the basis for marker evaluation. Other measures of prediction...

  7. Assimilation of SMOS Retrievals in the Land Information System

    Science.gov (United States)

    Blankenship, Clay B.; Case, Jonathan L.; Zavodsky, Bradley T.; Crosson, William L.

    2016-01-01

    The Soil Moisture and Ocean Salinity (SMOS) satellite provides retrievals of soil moisture in the upper 5 cm with a 30-50 km resolution and a mission accuracy requirement of 0.04 cm(sub 3 cm(sub -3). These observations can be used to improve land surface model soil moisture states through data assimilation. In this paper, SMOS soil moisture retrievals are assimilated into the Noah land surface model via an Ensemble Kalman Filter within the NASA Land Information System. Bias correction is implemented using Cumulative Distribution Function (CDF) matching, with points aggregated by either land cover or soil type to reduce sampling error in generating the CDFs. An experiment was run for the warm season of 2011 to test SMOS data assimilation and to compare assimilation methods. Verification of soil moisture analyses in the 0-10 cm upper layer and root zone (0-1 m) was conducted using in situ measurements from several observing networks in the central and southeastern United States. This experiment showed that SMOS data assimilation significantly increased the anomaly correlation of Noah soil moisture with station measurements from 0.45 to 0.57 in the 0-10 cm layer. Time series at specific stations demonstrate the ability of SMOS DA to increase the dynamic range of soil moisture in a manner consistent with station measurements. Among the bias correction methods, the correction based on soil type performed best at bias reduction but also reduced correlations. The vegetation-based correction did not produce any significant differences compared to using a simple uniform correction curve.

  8. A virtual reality catchment for data assimilation experiments

    Science.gov (United States)

    Schalge, Bernd; Rihani, Jehan; Haese, Barbara; Baroni, Gabriele; Erdal, Daniel; Neuweiler, Insa; Hendricks-Franssen, Harrie-Jan; Geppert, Gernot; Ament, Felix; Kollet, Stefan; Cirpka, Olaf; Saavedra, Pablo; Han, Xujun; Attinger, Sabine; Kunstmann, Harald; Vereecken, Harry; Simmer, Clemens

    2016-04-01

    Current data assimilation (DA) systems often lack the possibility to assimilate measurements across compartments to accurately estimate states and fluxes in subsurface-land surface-atmosphere systems (SLAS). In order to develop a new DA framework that is able to realize this cross-compartmental assimilation a comprehensive testing environment is needed. Therefore a virtual reality (VR) catchment is constructed with the Terrestrial System Modeling Platform (TerrSysMP). This catchment mimics the Neckar catchment in Germany. TerrSysMP employs the atmospheric model COSMO, the land surface model CLM and the hydrological model ParFlow coupled with the external coupler OASIS. We will show statistical tests to prove the plausibility of the VR. The VR is running in a fully-coupled mode (subsurface - land surface - atmosphere) which includes the interactions of subsurface dynamics with the atmosphere, such as the effects of soil moisture, which can influence near-surface temperatures, convection patterns or the surface heat fluxes. A reference high resolution run serves as the "truth" from which virtual observations are extracted with observation operators like virtual rain gauges, synoptic stations and satellite observations (amongst others). This effectively solves the otherwise often encountered data scarcity issues with respect to DA. Furthermore an ensemble of model runs at a reduced resolution is performed. This ensemble serves also for open loop runs to be compared with data assimilation experiments. The model runs with this ensemble served to identify sets of parameters that are especially sensitive to changes and have the largest impact on the system. These parameters were the focus of subsequent ensemble simulations and DA experiments. We will show to what extend the VR states can be re-constructed using data assimilation methods with only a limited number of virtual observations available.

  9. Development of KIAPS Observation Processing Package for Data Assimilation System

    Science.gov (United States)

    Kang, Jeon-Ho; Chun, Hyoung-Wook; Lee, Sihye; Han, Hyun-Jun; Ha, Su-Jin

    2015-04-01

    The Korea Institute of Atmospheric Prediction Systems (KIAPS) was founded in 2011 by the Korea Meteorological Administration (KMA) to develop Korea's own global Numerical Weather Prediction (NWP) system as nine year (2011-2019) project. Data assimilation team at KIAPS has been developing the observation processing system (KIAPS Package for Observation Processing: KPOP) to provide optimal observations to the data assimilation system for the KIAPS Global Model (KIAPS Integrated Model - Spectral Element method based on HOMME: KIM-SH). Currently, the KPOP is capable of processing the satellite radiance data (AMSU-A, IASI), GPS Radio Occultation (GPS-RO), AIRCRAFT (AMDAR, AIREP, and etc…), and synoptic observation (SONDE and SURFACE). KPOP adopted Radiative Transfer for TOVS version 10 (RTTOV_v10) to get brightness temperature (TB) for each channel at top of the atmosphere (TOA), and Radio Occultation Processing Package (ROPP) 1-dimensional forward module to get bending angle (BA) at each tangent point. The observation data are obtained from the KMA which has been composited with BUFR format to be converted with ODB that are used for operational data assimilation and monitoring at the KMA. The Unified Model (UM), Community Atmosphere - Spectral Element (CAM-SE) and KIM-SH model outputs are used for the bias correction (BC) and quality control (QC) of the observations, respectively. KPOP provides radiance and RO data for Local Ensemble Transform Kalman Filter (LETKF) and also provides SONDE, SURFACE and AIRCRAFT data for Three-Dimensional Variational Assimilation (3DVAR). We are expecting all of the observation type which processed in KPOP could be combined with both of the data assimilation method as soon as possible. The preliminary results from each observation type will be introduced with the current development status of the KPOP.

  10. ASSIMILATION OF COARSE-SCALEDATAUSINGTHE ENSEMBLE KALMAN FILTER

    KAUST Repository

    Efendiev, Yalchin

    2011-01-01

    Reservoir data is usually scale dependent and exhibits multiscale features. In this paper we use the ensemble Kalman filter (EnKF) to integrate data at different spatial scales for estimating reservoir fine-scale characteristics. Relationships between the various scales is modeled via upscaling techniques. We propose two versions of the EnKF to assimilate the multiscale data, (i) where all the data are assimilated together and (ii) the data are assimilated sequentially in batches. Ensemble members obtained after assimilating one set of data are used as a prior to assimilate the next set of data. Both of these versions are easily implementable with any other upscaling which links the fine to the coarse scales. The numerical results with different methods are presented in a twin experiment setup using a two-dimensional, two-phase (oil and water) flow model. Results are shown with coarse-scale permeability and coarse-scale saturation data. They indicate that additional data provides better fine-scale estimates and fractional flow predictions. We observed that the two versions of the EnKF differed in their estimates when coarse-scale permeability is provided, whereas their results are similar when coarse-scale saturation is used. This behavior is thought to be due to the nonlinearity of the upscaling operator in the case of the former data. We also tested our procedures with various precisions of the coarse-scale data to account for the inexact relationship between the fine and coarse scale data. As expected, the results show that higher precision in the coarse-scale data yielded improved estimates. With better coarse-scale modeling and inversion techniques as more data at multiple coarse scales is made available, the proposed modification to the EnKF could be relevant in future studies.

  11. NETS - Danish participation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Alsen, S. (Grontmij - Carl Bro, Glostrup (Denmark)); Theel, C. (Baltic Sea Solutions, Holeby (Denmark))

    2008-12-15

    Within the NICe-funded project 'Nordic Environmental Technology Solutions (NETS)' a new type of networking at the Nordic level was organized in order to jointly exploit the rapidly growing market potential in the environmental technology sector. The project aimed at increased and professionalized commercialization of Nordic Cleantech in energy and water business segments through 1) closer cooperation and joint marketing activities, 2) a website, 3) cleantech product information via brochures and publications 4) and participating in relevant trade fairs and other industry events. Facilitating business-to-business activities was another core task for the NETS project partners from Norway, Sweden, Finland and Denmark with the aim to encourage total solutions for combined Cleantech system offers. The project has achieved to establish a Cleantech register of 600 Nordic Cleantech companies, a network of 86 member enterprises, produced several publications and brochures for direct technology promotion and a website for direct access to company profiles and contact data. The project partners have attended 14 relevant international Cleantech trade fairs and conferences and facilitated business-to-business contacts added by capacity building offers through two company workshops. The future challenge for the project partners and Nordic Cleantech will be to coordinate the numerous efforts within the Nordic countries in order to reach concerted action and binding of member companies for reliable services, an improved visibility and knowledge exchange. With Cleantech's growing market influence and public awareness, the need to develop total solutions is increasing likewise. Marketing efforts should be encouraged cross-sectional and cross-border among the various levels of involved actors from both the public and the private sector. (au)

  12. NETS - Danish participation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Alsen, S [Grontmij - Carl Bro, Glostrup (Denmark); Theel, C [Baltic Sea Solutions, Holeby (Denmark)

    2008-12-15

    Within the NICe-funded project 'Nordic Environmental Technology Solutions (NETS)' a new type of networking at the Nordic level was organized in order to jointly exploit the rapidly growing market potential in the environmental technology sector. The project aimed at increased and professionalized commercialization of Nordic Cleantech in energy and water business segments through 1) closer cooperation and joint marketing activities, 2) a website, 3) cleantech product information via brochures and publications 4) and participating in relevant trade fairs and other industry events. Facilitating business-to-business activities was another core task for the NETS project partners from Norway, Sweden, Finland and Denmark with the aim to encourage total solutions for combined Cleantech system offers. The project has achieved to establish a Cleantech register of 600 Nordic Cleantech companies, a network of 86 member enterprises, produced several publications and brochures for direct technology promotion and a website for direct access to company profiles and contact data. The project partners have attended 14 relevant international Cleantech trade fairs and conferences and facilitated business-to-business contacts added by capacity building offers through two company workshops. The future challenge for the project partners and Nordic Cleantech will be to coordinate the numerous efforts within the Nordic countries in order to reach concerted action and binding of member companies for reliable services, an improved visibility and knowledge exchange. With Cleantech's growing market influence and public awareness, the need to develop total solutions is increasing likewise. Marketing efforts should be encouraged cross-sectional and cross-border among the various levels of involved actors from both the public and the private sector. (au)

  13. Higher-moment measurements of net-kaon, net-charge and net-proton multiplicity distributions at STAR

    International Nuclear Information System (INIS)

    Sarkar, Amal

    2014-01-01

    In this paper, we report the measurements of the various moments, such as mean, standard deviation (σ), skewness (S) and kurtosis (κ) of the net-kaon, net-charge and net-proton multiplicity distributions at mid-rapidity in Au + Au collisions from √(s NN )=7.7 to 200 GeV with the STAR experiment at RHIC. This work has been done with the aim to locate the critical point on the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as well as to the correlation length of the system which diverges in an ideal infinite thermodynamic system at the critical point. For a finite system, existing for a finite time, a non-monotonic behavior of these variables would indicate the presence of the critical point. Furthermore, we also present the moment products Sσ, κσ 2 of net-kaon, net-charge and net-proton multiplicity distributions as a function of collision centrality and energy. The energy and the centrality dependence of higher moments and their products have been compared with different models

  14. A problem-solving environment for data assimilation in air quality modelling

    NARCIS (Netherlands)

    Velzen, N. van; Segers, A.J.

    2010-01-01

    A generic toolbox for data assimilation called COSTA (COmmon Set of Tools for the Assimilation of data) makes it possible to simplify the application of data assimilation to models and to try out various methods for a particular model. Concepts of object oriented programming are used to define

  15. Uncertainty in Forest Net Present Value Estimations

    Directory of Open Access Journals (Sweden)

    Ilona Pietilä

    2010-09-01

    Full Text Available Uncertainty related to inventory data, growth models and timber price fluctuation was investigated in the assessment of forest property net present value (NPV. The degree of uncertainty associated with inventory data was obtained from previous area-based airborne laser scanning (ALS inventory studies. The study was performed, applying the Monte Carlo simulation, using stand-level growth and yield projection models and three alternative rates of interest (3, 4 and 5%. Timber price fluctuation was portrayed with geometric mean-reverting (GMR price models. The analysis was conducted for four alternative forest properties having varying compartment structures: (A a property having an even development class distribution, (B sapling stands, (C young thinning stands, and (D mature stands. Simulations resulted in predicted yield value (predicted NPV distributions at both stand and property levels. Our results showed that ALS inventory errors were the most prominent source of uncertainty, leading to a 5.1–7.5% relative deviation of property-level NPV when an interest rate of 3% was applied. Interestingly, ALS inventory led to significant biases at the property level, ranging from 8.9% to 14.1% (3% interest rate. ALS inventory-based bias was the most significant in mature stand properties. Errors related to the growth predictions led to a relative standard deviation in NPV, varying from 1.5% to 4.1%. Growth model-related uncertainty was most significant in sapling stand properties. Timber price fluctuation caused the relative standard deviations ranged from 3.4% to 6.4% (3% interest rate. The combined relative variation caused by inventory errors, growth model errors and timber price fluctuation varied, depending on the property type and applied rates of interest, from 6.4% to 12.6%. By applying the methodology described here, one may take into account the effects of various uncertainty factors in the prediction of forest yield value and to supply the

  16. Application of Observed Precipitation in NCEP Global and Regional Data Assimilation Systems, Including Reanalysis and Land Data Assimilation

    Science.gov (United States)

    Mitchell, K. E.

    2006-12-01

    The Environmental Modeling Center (EMC) of the National Centers for Environmental Prediction (NCEP) applies several different analyses of observed precipitation in both the data assimilation and validation components of NCEP's global and regional numerical weather and climate prediction/analysis systems (including in NCEP global and regional reanalysis). This invited talk will survey these data assimilation and validation applications and methodologies, as well as the temporal frequency, spatial domains, spatial resolution, data sources, data density and data quality control in the precipitation analyses that are applied. Some of the precipitation analyses applied by EMC are produced by NCEP's Climate Prediction Center (CPC), while others are produced by the River Forecast Centers (RFCs) of the National Weather Service (NWS), or by automated algorithms of the NWS WSR-88D Radar Product Generator (RPG). Depending on the specific type of application in data assimilation or model forecast validation, the temporal resolution of the precipitation analyses may be hourly, daily, or pentad (5-day) and the domain may be global, continental U.S. (CONUS), or Mexico. The data sources for precipitation include ground-based gauge observations, radar-based estimates, and satellite-based estimates. The precipitation analyses over the CONUS are analyses of either hourly, daily or monthly totals of precipitation, and they are of two distinct types: gauge-only or primarily radar-estimated. The gauge-only CONUS analysis of daily precipitation utilizes an orographic-adjustment technique (based on the well-known PRISM precipitation climatology of Oregon State University) developed by the NWS Office of Hydrologic Development (OHD). The primary NCEP global precipitation analysis is the pentad CPC Merged Analysis of Precipitation (CMAP), which blends both gauge observations and satellite estimates. The presentation will include a brief comparison between the CMAP analysis and other global

  17. Determinants of the net interest margins in BH banks

    Directory of Open Access Journals (Sweden)

    Plakalović Novo

    2015-01-01

    Full Text Available In this paper, the subject of analysis is influence of certain macroeconomic and microeconomic variables on bank net interest margins in Bosnia and Herzegovina (BH for the period from 2008 to 2013 through a multiple linear regression models. The level and dynamics of NIM indicate the efficiency of financial intermediation. The observed period is characterized by the reduction in net interest margins of banks over the previous decade, which was characterized by high GDP growth, bank loans and high-interest rates and high profitability. Therefore, this study examines the factors that affect the level of net interest margins in the domestic banking industry. The main objective of this paper is to determine whether there is interdependence in the movement between the independent and dependent variables through a multiple linear regression. The net interest margin will be observed as a dependent variable, and liquidity risk, operating costs, credit risk, the index of market concentration, funding risk, the growth rate of gross domestic product and consumer price index will be used as independent variables.

  18. Determining metal assimilation efficiency in aquatic invertebrates using enriched stable metal isotope tracers

    International Nuclear Information System (INIS)

    Croteau, Marie-Noele; Luoma, Samuel N.; Pellet, Bastien

    2007-01-01

    We employ a novel approach that combines pulse-chase feeding and multi-labelled stable isotopes to determine gut passage time (GPT), gut retention time (GRT), food ingestion rate (IR) and assimilation efficiency (AE) of three trace elements for a freshwater gastropod. Lettuce isotopically enriched in 53 Cr, 65 Cu and 106 Cd was fed for 2 h to Lymnaea stagnalis. The release of tracers in feces and water was monitored for 48 h, during which unlabelled lettuce was provided ad libidum. The first defecation of 53 Cr occurred after 5 h of depuration (GPT), whereas 90% of the ingested 53 Cr was recovered in the feces after 22.5 h of depuration (GRT). 53 Chromium was not significantly accumulated in the soft tissues upon exposure. In contrast, 65 Cu and 106 Cd assimilation was detectable for most experimental snails, i.e., 65/63 Cu and 106/114 Cd ratios in exposed snails were higher than those for controls. Food IR during the labelled feeding phase was 0.16 ± 0.07 g g -1 d -1 . IR was inferred from the amount of 53 Cr egested in the feces during depuration and the concentration of 53 Cr in the labelled lettuce. Assimilation efficiencies (±95% CI) determined using mass balance calculations were 84 ± 4% for Cu and 85 ± 3% for Cd. The ratio method yields similar AE estimates. Expanding the application of this novel stable isotope tracer technique to other metals in a wide variety of species will provide unique opportunities to evaluate the interplay between digestive processes and dietary influx of metals. Understanding the biological processes that modulate dietborne metal uptake is crucial to assess the toxicity of dietborne metals

  19. Application and Theory of Petri Nets

    DEFF Research Database (Denmark)

    This volume contains the proceedings of the 13th International Conference onApplication and Theory of Petri Nets, held in Sheffield, England, in June 1992. The aim of the Petri net conferences is to create a forum for discussing progress in the application and theory of Petri nets. Typically....... Balbo and W. Reisig, 18 submitted papers, and seven project papers. The submitted papers and project presentations were selectedby the programme committee and a panel of referees from a large number of submissions....

  20. TwiddleNet: Smartphones as Personal Servers

    OpenAIRE

    Gurminder, Singh; Center for the Study of Mobile Devices and Communications

    2012-01-01

    TwiddleNet uses smartphones as personal servers to enable instant content capture and dissemination for firstresponders. It supports the information sharing needs of first responders in the early stages of an emergency response operation. In TwiddleNet, content, once captured, is automatically tagged and disseminated using one of the several networking channels available in smartphones. TwiddleNet pays special attention to minimizing the equipment, network set-up time, and content...