Improved Estimates of Moments and Winds from Radar Wind Profiler
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Helmus, Jonathan [Argonne National Lab. (ANL), Argonne, IL (United States); Ghate, Virendra P. [Argonne National Lab. (ANL), Argonne, IL (United States)
2017-01-02
The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) operates nine radar wind profilers (RWP) across its sites. These RWPs operate at 915 MHz or 1290 MHz frequency and report the first three moments of the Doppler spectrum. The operational settings of the RWP were modified in summer, 2015 to have single pulse length setting for the wind mode and two pulse length settings for the precipitation mode. The moments data collected during the wind mode are used to retrieve horizontal winds. The vendor-reported winds are available at variable time resolution (10 mins, 60 mins, etc.) and contain a significant amount of contamination due to noise and clutter. In this data product we have recalculated the moments and the winds from the raw radar Doppler spectrum and have made efforts to mitigate the contamination due to instrument noise in the wind estimates. Additionally, the moments and wind data has been reported in a harmonized layout identical for all locations and sites.
Callahan, Patrick Gregory
A fundamental objective of materials science and engineering is to understand the structure-property-processing-performance relationship. We need to know the true 3-D microstructure of a material to understand certain geometric properties of a material, and thus fulfill this objective. Focused ion beam (FIB) serial sectioning allows us to find the true 3-D microstructure of Ni-base superalloys. Once the true 3-D microstructure is obtained, an accurate quantitative description and characterization of precipitate and/or grain shapes is needed to understand the microstructure and describe it in an unbiased way. In this thesis, second order moment invariants, the shape quotient Q, a convexity measure relating the volume of an object to the volume of its convex hull, V/Vconv, and Gaussian curvature have been used to compare an experimentally observed polycrystalline IN100 microstructure to three synthetic microstructures. The three synthetic microstructures used different shape classes to produce starting grain shapes. The three shape classes are ellipsoids, superellipsoids, and the shapes generated when truncating a cube with an octahedron. The microstructures are compared using a distance measure, the Hellinger distance. The Hellinger distance is used to compare distributions of shape descriptors for the grains in each microstructure. The synthetic microstructure that has the smallest Hellinger distance, and so best matched the experimentally observed microstructure is the microstructure that used superellipsoids as a starting grain shape. While it has the smallest Hellinger distance, and is approaching realistic grain morphologies, the superellipsoidal microstructure is still not realistic. Second order moment invariants, Q, and V/V conv have also been used to characterize the γ' precipitate shapes from four experimental Ru-containing Ni-base superalloys with differences in alloying additions. The superalloys are designated UM-F9, UM-F18, UM-F19, and UM-F22. The
Mobile Three Frequency Radar as Research Platform for Precipitation Profiling
Schmidt, Walter; Rautiainen, Kimmo; Harri, Ari-Matti
2014-05-01
Precipitation profiling at the frequency bands of Ku, Ka and W bands are becoming increasingly popular in the studies of atmospheric microphysics. Ever since the introduction of Ku / Ka pair of frequencies for the Global Precipitation Measurement mission (GPM) and the success of W band in Cloudsat, the interest in precipitation profiling using these frequencies has increased. The profiling observations will also serve as ground validation instruments for several space missions such as GPM and EarthCARE [1]. In order to get better information to retrieve ice microphysics as well as to enhance sensitivity, we need to move from the standard S- and C-band weather radars to higher frequencies [2]. As was recently shown, the use of multi- frequency profiling yields important additional information compared to single-frequency radar mapping [3]. During the past four years a consortium of research, academic and private industries in Finland has been developing a flexible low-cost mobile three-band radar system for precipitation profiling. The feasibility of the concept is being demonstrated by implementing the Ku- and Ka-band part of the system. The antenna structure with antennas for Ku-, Ka- and W-band is completed allowing the pointing of all three antenna systems into the same direction during an azimuth and elevation scan. Using a freely programmable digital waveform generator and decoding electronics for the received data, the implementation of different wave form generation, compression and decoding schemes and their influence on the radar performance in the different bands can be evaluated and optimized. The modular design allows the connection of different transmitter control and receiver decoding units to any of the three band front-end electronics to evaluate the performance of different approaches in the various bands simultaneously. A real-time analysis software supports the data interpretation and system optimization during field tests. Via mobile internet
Directory of Open Access Journals (Sweden)
Nemanja Kovačević
2015-04-01
Full Text Available In this study, two bulk microphysical schemes were compared across mean radius values of the entire drop spectra. A cloud-resolving mesoscale model was used to analyze surface precipitation characteristics. The model included the following microphysical categories: water vapour, cloud droplets, raindrops, ice crystals, snow, graupel, frozen raindrops and hail. Two bulk schemes were used: a single-moment scheme in which the mean radius was specified as a parameter and a double-moment scheme in which the mean radius of drops was calculated diagnostically with a fixed value for the cloud droplet number concentration. Experiments were conducted out for three values of the mean radius (in the single-moment scheme and two cloud droplet number concentrations (in the double-moment scheme. There were large differences in the surface precipitation for the two schemes, the simulated precipitation generated by the double-moment scheme had a higher sensitivity. The single-moment scheme generated an unrealistic collection rate of cloud droplets by raindrops and hail as well as unrealistic evaporation of rain and melting of solid hydrometeors; these processes led to inaccurate timing and amounts of surface precipitation.
Low-Friction, Low-Profile, High-Moment Two-Axis Joint
Lewis, James L.; Le, Thang; Carroll, Monty B.
2010-01-01
The two-axis joint is a mechanical device that provides two-degrees-of-freedom motion between connected components. A compact, moment-resistant, two-axis joint is used to connect an electromechanical actuator to its driven structural members. Due to the requirements of the overall mechanism, the joint has a low profile to fit within the allowable space, low friction, and high moment-reacting capability. The mechanical arrangement of this joint can withstand high moments when loads are applied. These features allow the joint to be used in tight spaces where a high load capability is required, as well as in applications where penetrating the mounting surface is not an option or where surface mounting is required. The joint consists of one base, one clevis, one cap, two needle bearings, and a circular shim. The base of the joint is the housing (the base and the cap together), and is connected to the grounding structure via fasteners and a bolt pattern. Captive within the housing, between the base and the cap, are the rotating clevis and the needle bearings. The clevis is attached to the mechanical system (linear actuator) via a pin. This pin, and the rotational movement of the clevis with respect to the housing, provides two rotational degrees of freedom. The larger diameter flange of the clevis is sandwiched between a pair of needle bearings, one on each side of the flange. During the assembly of the two-axis joint, the circular shims are used to adjust the amount of preload that is applied to the needle bearings. The above arrangement enables the joint to handle high moments with minimal friction. To achieve the high-moment capability within a low-profile joint, the use of depth of engagement (like that of a conventional rotating shaft) to react moment is replaced with planar engagement parallel to the mounting surface. The needle bearings with the clevis flange provide the surface area to react the clevis loads/moments into the joint housing while providing minimal
Awan, Shaheen N; Krauss, Andrew R; Herbst, Christian T
2015-09-01
To date, only a few studies have examined the possible relationship between electroglottographic (EGG) data and spectral characteristics of the voice. This study examined the possible association between EGG signal data (contact quotient [CQ] and decontacting phase profile) and spectral moments of the acoustic signal (spectral mean, spectral standard deviation (SD), spectral skewness, and spectral kurtosis). Furthermore, the possible effects of gender on these measurements were analyzed. Sustained vowel /ɑ/ productions were obtained from 48 normophonic individuals (24 adult males and 24 adult females). The central 1-second portions of the acoustic vowel samples were analyzed for spectral moments, and the EGG signal was analyzed for CQ (CQEGG), fundamental frequency (F0), and decontacting phase profile. Across all subjects, the spectral characteristics of the voice (in particular, spectral SD, skewness, and kurtosis) are significantly related to changes in the relative duration of vocal fold contact (as measured via CQEGG). In addition, significant effects of the profile of the EGG decontacting phase (ie, concave down/"knee" vs concave up/"no knee") on spectral SD were also observed, as well as a strong trend for decontacting phase profile to influence the spectral mean. Although the degree of vocal fold contact and differences in decontacting phase profile may have an influence on the spectral characteristics of the acoustic voice signal, the strength of correlations between CQEGG values and measures of spectral moments only accounted for approximately 13-16% of the variation in spectral distribution characteristics. These results stress the importance of the transformative role of the supraglottal vocal tract in producing an acoustic output that maintains some of the characteristics of the glottal source, but which modifies the source characteristics in ways not completely accounted for by single parameters such as CQEGG or EGG profile. Copyright © 2015 The
Masunaga, Hirohiko; Kummerow, Christian D.
2005-01-01
A methodology to analyze precipitation profiles using the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and precipitation radar (PR) is proposed. Rainfall profiles are retrieved from PR measurements, defined as the best-fit solution selected from precalculated profiles by cloud-resolving models (CRMs), under explicitly defined assumptions of drop size distribution (DSD) and ice hydrometeor models. The PR path-integrated attenuation (PIA), where available, is further used to adjust DSD in a manner that is similar to the PR operational algorithm. Combined with the TMI-retrieved nonraining geophysical parameters, the three-dimensional structure of the geophysical parameters is obtained across the satellite-observed domains. Microwave brightness temperatures are then computed for a comparison with TMI observations to examine if the radar-retrieved rainfall is consistent in the radiometric measurement space. The inconsistency in microwave brightness temperatures is reduced by iterating the retrieval procedure with updated assumptions of the DSD and ice-density models. The proposed methodology is expected to refine the a priori rain profile database and error models for use by parametric passive microwave algorithms, aimed at the Global Precipitation Measurement (GPM) mission, as well as a future TRMM algorithms.
Chou, S.-H.; Zavodsky, B. T.; Jedloved, G. J.
2010-01-01
In data sparse regions, remotely-sensed observations can be used to improve analyses and lead to better forecasts. One such source comes from the Atmospheric Infrared Sounder (AIRS), which together with the Advanced Microwave Sounding Unit (AMSU), provides temperature and moisture profiles in clear and cloudy regions with accuracy which approaches that of radiosondes. The purpose of this paper is to describe an approach to assimilate AIRS thermodynamic profile data into a regional configuration of the Advanced Research WRF (ARW) model using WRF-Var. Quality indicators are used to select only the highest quality temperature and moisture profiles for assimilation in clear and partly cloudy regions, and uncontaminated portions of retrievals above clouds in overcast regions. Separate error characteristics for land and water profiles are also used in the assimilation process. Assimilation results indicate that AIRS profiles produce an analysis closer to in situ observations than the background field. Forecasts from a 37-day case study period in the winter of 2007 show that AIRS profile data can lead to improvements in 6-h cumulative precipitation forecasts resulting from improved thermodynamic fields. Additionally, in a convective heavy rainfall event from February 2007, assimilation of AIRS profiles produces a more unstable boundary layer resulting in enhanced updrafts in the model. These updrafts produce a squall line and precipitation totals that more closely reflect ground-based observations than a no AIRS control forecast. The location of available high-quality AIRS profiles ahead of approaching storm systems is found to be of paramount importance to the amount of impact the observations will have on the resulting forecasts.
Directory of Open Access Journals (Sweden)
Jinyu Gao
2017-11-01
Full Text Available Spaceborne precipitation radars are powerful tools used to acquire adequate and high-quality precipitation estimates with high spatial resolution for a variety of applications in hydrological research. The Global Precipitation Measurement (GPM mission, which deployed the first spaceborne Ka- and Ku-dual frequency radar (DPR, was launched in February 2014 as the upgraded successor of the Tropical Rainfall Measuring Mission (TRMM. This study matches the swath data of TRMM PR and GPM DPR Level 2 products during their overlapping periods at the global scale to investigate their similarities and DPR’s improvements concerning precipitation amount estimation and type classification of GPM DPR over TRMM PR. Results show that PR and DPR agree very well with each other in the global distribution of precipitation, while DPR improves the detectability of precipitation events significantly, particularly for light precipitation. The occurrences of total precipitation and the light precipitation (rain rates < 1 mm/h detected by GPM DPR are ~1.7 and ~2.53 times more than that of PR. With regard to type classification, the dual-frequency (Ka/Ku and single frequency (Ku methods performed similarly. In both inner (the central 25 beams and outer swaths (1–12 beams and 38–49 beams of DPR, the results are consistent. GPM DPR improves precipitation type classification remarkably, reducing the misclassification of clouds and noise signals as precipitation type “other” from 10.14% of TRMM PR to 0.5%. Generally, GPM DPR exhibits the same type division for around 82.89% (71.02% of stratiform (convective precipitation events recognized by TRMM PR. With regard to the freezing level height and bright band (BB height, both radars correspond with each other very well, contributing to the consistency in stratiform precipitation classification. Both heights show clear latitudinal dependence. Results in this study shall contribute to future development of spaceborne
Jékely, Gáspár; Arendt, Detlev
2007-06-01
The determination of gene expression patterns in three dimensions with cellular resolution is an important goal in developmental biology. However the most sensitive, efficient, and widely used staining technique for whole-mount in situ hybridization (WMISH), nitroblue tetrazolium (NBT)/5-bromo-4-chloro-3-indolyl phosphate (BCIP) precipitation by alkaline phosphatase, could not yet be combined with the most precise, high-resolution detection technique, confocal laser-scanning microscopy (CLSM). Here we report the efficient visualization of the NBT/BCIP precipitate using confocal reflection microscopy for WMISH samples of Drosophila, zebrafish, and the marine annelid worm, Platynereis dumerilii. In our simple WMISH protocol for reflection CLSM, NBT/BCIP staining can be combined with fluorescent WMISH, immunostainings, or transgenic green fluorescent protein (GFP) marker lines, allowing double labeling of cell types or of embryological structures of interest. Whole-mount reflection CLSM will thus greatly facilitate large-scale cellular resolution expression profiling in vertebrate and invertebrate model organisms.
Jinyu Gao; Guoqiang Tang; Yang Hong
2017-01-01
Spaceborne precipitation radars are powerful tools used to acquire adequate and high-quality precipitation estimates with high spatial resolution for a variety of applications in hydrological research. The Global Precipitation Measurement (GPM) mission, which deployed the first spaceborne Ka- and Ku-dual frequency radar (DPR), was launched in February 2014 as the upgraded successor of the Tropical Rainfall Measuring Mission (TRMM). This study matches the swath data of TRMM PR and GPM DPR Leve...
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Guo, Y.R.; Zou, X.; Kuo, Y.H. [National Center for Atmospheric Research, Boulder, CO (United States)
1996-04-01
Atmospheric moisture distribution is directly related to the formation of clouds and precipitation and affects the atmospheric radiation and climate. Currently, several remote sensing systems can measure precipitable water (PW) with fairly high accuracy. As part of the development of an Integrated Data Assimilation and Sounding System in support of the Atmospheric Radiation Measurement Program, retrieving the 3-D water vapor fields from PW measurements is an important problem. A new four dimensional variational (4DVAR) data assimilation system based on the Penn State/National Center for Atmospheric Research (NCAR) mesoscale model (MM5) has been developed by Zou et al. (1995) with the adjoint technique. In this study, we used this 4DVAR system to retrieve the moisture profiles. Because we do not have a set of real observed PW measurements now, the special soundings collected during the Severe Environmental Storm and Mesoscale Experiment (SESAME) in 1979 were used to simulate a set of PW measurements, which were then assimilated into the 4DVAR system. The accuracy of the derived water vapor fields was assessed by direct comparison with the detailed specific humidity soundings. The impact of PW assimilation on precipitation forecast was examined by conducting a series of model forecast experiments started from the different initial conditions with or without data assimilation.
Fujita, Mikiko; Sato, Tomonori
2017-07-06
Extremely heavy precipitation affects human society and the natural environment, and its behaviour under a warming climate needs to be elucidated. Recent studies have demonstrated that observed extreme precipitation increases with surface air temperature (SAT) at approximately the Clausius-Clapeyron (CC) rate, suggesting that atmospheric water vapour content can explain the relationship between extreme precipitation and SAT. However, the relationship between atmospheric water vapour content and SAT is poorly understood due to the lack of reliable observations with sufficient spatial and temporal coverage for statistical analyses. Here, we analyse the relationship between atmospheric water vapour content and SAT using precipitable water vapour (PWV) derived from global positioning system satellites. A super-CC rate appears in hourly PWV when the SAT is below 16 °C, whereas the rate decreases at high SAT, which is different from the precipitation-SAT relationship. The effects of upper air temperature and water vapour can consistently explain the super-CC rate of PWV relative to SAT. The difference between moist and dry adiabatic lapse rates increases with SAT, in consequence of more ability to hold water vapour in the free atmosphere under higher SAT conditions; therefore, attainable PWV increases more rapidly than the CC rate as SAT increases.
Montopoli, Mario; Roberto, Nicoletta; Adirosi, Elisa; Gorgucci, Eugenio; Baldini, Luca
2017-04-01
Weather radars are nowadays a unique tool to estimate quantitatively the rain precipitation near the surface. This is an important task for a plenty of applications. For example, to feed hydrological models, mitigate the impact of severe storms at the ground using radar information in modern warning tools as well as aid the validation studies of satellite-based rain products. With respect to the latter application, several ground validation studies of the Global Precipitation Mission (GPM) products have recently highlighted the importance of accurate QPE from ground-based weather radars. To date, a plenty of works analyzed the performance of various QPE algorithms making use of actual and synthetic experiments, possibly trained by measurement of particle size distributions and electromagnetic models. Most of these studies support the use of dual polarization variables not only to ensure a good level of radar data quality but also as a direct input in the rain estimation equations. Among others, one of the most important limiting factors in radar QPE accuracy is the vertical variability of particle size distribution that affects at different levels, all the radar variables acquired as well as rain rates. This is particularly impactful in mountainous areas where the altitudes of the radar sampling is likely several hundred of meters above the surface. In this work, we analyze the impact of the vertical profile variations of rain precipitation on several dual polarization radar QPE algorithms when they are tested a in complex orography scenario. So far, in weather radar studies, more emphasis has been given to the extrapolation strategies that make use of the signature of the vertical profiles in terms of radar co-polar reflectivity. This may limit the use of the radar vertical profiles when dual polarization QPE algorithms are considered because in that case all the radar variables used in the rain estimation process should be consistently extrapolated at the surface
Williams, Kate
2012-01-01
The informatics moment is the moment when a person seeks help in using some digital technology that is new to him or her. This article examines the informatics moment in people's everyday lives as they sought help at a branch public library. Four types of literacy were involved: basic literacy (reading and writing), computer literacy (use of a…
Paul R. Reed; Carol J. Cumber
2000-01-01
In October, 1996 Private Moments, an adult novelty store, opened for business in Huntsville, Texas. Huntsville had no ordinances in place to prevent the opening of this type of business. In fact, the local Small Business Development Center provided guidance and assistance to Edward Delagarza, the founder and owner of Private Moments. Many of the Huntsville citizens, unhappy with the opening of Private Moments, approached the City Council requesting that it be closed immediately and asked for ...
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Xiaolei Wang
2016-05-01
Full Text Available Due to the scarcity of field observations and geodetic measurements in catchments in the Karakoram Mountains in Western China, obtaining precipitation data for the high mountains involves large uncertainties and difficulties. In this study, we used a functional relationship between the annual glacier accumulation and summer temperature at the equilibrium line altitude (ELA to derive precipitation lapse rates (PLAPSs in a data-scarce watershed. These data were used in a modified Soil and Water Assessment Tool (SWAT model with a glacier module to simulate glacio-hydrological processes in the Yarkant River basin in the Karakoram. The PLAPS based on the widely-used grid datasets considerably underestimated precipitation, yielding an unreasonable watershed water balance and inaccurate glacier changes. However, the ELA-based PLAPS improved the simulation significantly. In the Yarkant River basin, the annual precipitation reached a peak of 800–1000 mm at approximately 5300 m a.s.l. The model simulations indicated that the contributions of glacier melt and ice melt to total runoff were 52% and 31%, respectively. Moreover, a significant precipitation increase and a non-significant temperature increase during the melt season may be the major reasons for the decreased ice melt and slower glacier shrinkage on the northern slope of the Karakoram during the period of 1968–2007.
Zavodsky, Bradley T.; Jedlovec, Gary J.; Blakenship, Clay B.; Wick, Gary A.; Neiman, Paul J.
2013-01-01
This project is a collaborative activity between the NASA Short-term Prediction Research and Transition (SPoRT) Center and the NOAA Hydrometeorology Testbed (HMT) to evaluate a SPoRT Advanced Infrared Sounding Radiometer (AIRS: Aumann et al. 2003) enhanced moisture analysis product. We test the impact of assimilating AIRS temperature and humidity profiles above clouds and in partly cloudy regions, using the three-dimensional variational Gridpoint Statistical Interpolation (GSI) data assimilation (DA) system (Developmental Testbed Center 2012) to produce a new analysis. Forecasts of the Weather Research and Forecasting (WRF) model initialized from the new analysis are compared to control forecasts without the additional AIRS data. We focus on some cases where atmospheric rivers caused heavy precipitation on the US West Coast. We verify the forecasts by comparison with dropsondes and the Cooperative Institute for Research in the Atmosphere (CIRA) Blended Total Precipitable Water product.
Wu, Xiaohua; Diak, George R.; Hayden, Cristopher M.; Young, John A.
1995-01-01
These observing system simulation experiments investigate the assimilation of satellite-observed water vapor and cloud liquid water data in the initialization of a limited-area primitive equations model with the goal of improving short-range precipitation forecasts. The assimilation procedure presented includes two aspects: specification of an initial cloud liquid water vertical distribution and diabatic initialization. The satellite data is simulated for the next generation of polar-orbiting satellite instruments, the Advanced Microwave Sounding Unit (AMSU) and the High-Resolution Infrared Sounder (HIRS), which are scheduled to be launched on the NOAA-K satellite in the mid-1990s. Based on cloud-top height and total column cloud liquid water amounts simulated for satellite data a diagnostic method is used to specify an initial cloud water vertical distribution and to modify the initial moisture distribution in cloudy areas. Using a diabatic initialization procedure, the associated latent heating profiles are directly assimilated into the numerical model. The initial heating is estimated by time averaging the latent heat release from convective and large-scale condensation during the early forecast stage after insertion of satellite-observed temperature, water vapor, and cloud water formation. The assimilation of satellite-observed moisture and cloud water, together withy three-mode diabatic initialization, significantly alleviates the model precipitation spinup problem, especially in the first 3 h of the forecast. Experimental forecasts indicate that the impact of satellite-observed temperature and water vapor profiles and cloud water alone in the initialization procedure shortens the spinup time for precipitation rates by 1-2 h and for regeneration of the areal coverage by 3 h. The diabatic initialization further reduces the precipitation spinup time (compared to adiabatic initialization) by 1 h.
McClelland, Jodie A; Feller, Julian A; Menz, Hylton B; Webster, Kate E
2014-06-03
The aim of this study was to investigate the prevalence of abnormal knee biomechanical patterns in 40 patients with a modern TKA prosthesis, compared to 40 matched control participants when ascending and descending stairs. Fewer patients were able to ascend (65%) or descend stairs (53%) unassisted than controls (83%). Of the participants who could ascend and descend, cluster analysis classified most patients (up to 77%) as demonstrating a similar knee moment pattern as all controls. A small subgroup of patients who completed the tasks did so with distinctly abnormal biomechanics compared to other patients and controls. These findings suggest that recovery of normal stair climbing is possible. However, rehabilitation might be more effective if it were tailored to account for these differences between patients. Copyright © 2014 Elsevier Ltd. All rights reserved.
Hekker, S.; Aerts, C.; Ridder, J. de; Carrier, F.
2006-01-01
Context: So far, red giant oscillations have been studied from radial velocity and/or light curve variations, which reveal frequencies of the oscillation modes. To characterise radial and non-radial oscillations, line profile variations are a valuable diagnostic. Here we present for the first time a
Temperature moments vs poison moments
Energy Technology Data Exchange (ETDEWEB)
Staebler, U.M.
1947-05-19
The excess reactivity available in an operating pile is absorbed in poison columns and horizontal rods. The temperature distribution of the pile is determined by the relative strengths and locations of the poison columns and the configuration of control rods used. A method for adjusting poison columns and rods to improve upon the pile`s temperature distribution is given in Document {number_sign}7-2654, ``Procedure for Improving Temperature Distribution via Rods and Columns,`` Wheeler and Menegus to Jordan, September 9, 1945. A relationship between poison moment (inhour lattice units) and temperature moments (per coat) was theoretically derived in the above document and has since been measured on several occasions on the basis of operating experience. A survey of recent operating data for the F Pile has been made by H. A. Gauper, Jr. with the intent of improving the method for obtaining the temperature and poison moments and relating changes in the two. This study was concerned with only the horizontal and vertical dipole moments. The results of Mr. Gauper`s investigation are summarized in this memorandum.
Energy Technology Data Exchange (ETDEWEB)
Bao Gang [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Higashi-Hiroshima, Hiroshima (Japan); Shinozaki, Kenji [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Higashi-Hiroshima, Hiroshima (Japan)]. E-mail: kshino@hiroshima-u.ac.jp; Inkyo, Muneyuki [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Higashi-Hiroshima, Hiroshima (Japan); Miyoshi, Tomohisa [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Higashi-Hiroshima, Hiroshima (Japan); Yamamoto, Motomichi [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Higashi-Hiroshima, Hiroshima (Japan); Mahara, Yoichi [Babcock-Hitachi K.K., 3-36 Takara-machi, Kure, Hiroshima (Japan); Watanabe, Hiroshi [Babcock-Hitachi K.K., 3-36 Takara-machi, Kure, Hiroshima (Japan)
2006-08-10
A model based on the thermodynamic and kinetic was conducted to simulate the Cr depletion profiles near the grain boundary in Inconel 600 during the heat treatments and laser surface melting (LSM) process using Thermo-Calc and Dictra code. Based on the good agreement of Cr concentration distribution during heat treatments measured by experiments, the microsegregation of Cr induced by cellular microstructure formed during the LSM process was also modeled. The Cr depletion profile was evaluated using the Cr depletion area below the critical Cr concentration for intergranular cracking/intergranular stress corrosion cracking (IGC/IGSCC) susceptibility (8 mass%). Comparing with the result of Streicher test, the Cr depletion area calculated showed good coherence with the IGC/IGSCC susceptibility. The sample after SR + LTS treatment with the largest Cr depletion area showed the worst IGC/IGSCC resistance, while, the sample after LSM process with the smaller Cr depletion area showed the excellent IGC/IGSCC resistance.
DEFF Research Database (Denmark)
Hastrup, Kirsten Blinkenberg
2017-01-01
as an experiment in real time, where insights gained intersubjectively gradually shape up as knowledge through analysis. This line of thought is brought to bear on a discussion of collaboration between anthropologists, archaeologists, and biologists in North West Greenland. Through actual experiences from...... the field, this article shows how knowledge generated on the edge of one’s familiar disciplinary territory may both expand and intensify the anthropological field. Collaborative moments are seen to make new anthropological insights emerge through the co-presence of several analytical perspectives...
Blankenship, Clay; Zavodsky, Bradley; Jedlovec, Gary; Wick, Gary; Neiman, Paul
2013-01-01
Atmospheric rivers are transient, narrow regions in the atmosphere responsible for the transport of large amounts of water vapor. These phenomena can have a large impact on precipitation. In particular, they can be responsible for intense rain events on the western coast of North America during the winter season. This paper focuses on attempts to improve forecasts of heavy precipitation events in the Western US due to atmospheric rivers. Profiles of water vapor derived from from Atmospheric Infrared Sounder (AIRS) observations are combined with GFS forecasts by a three-dimensional variational data assimilation in the Gridpoint Statistical Interpolation (GSI). Weather Research and Forecasting (WRF) forecasts initialized from the combined field are compared to forecasts initialized from the GFS forecast only for 3 test cases in the winter of 2011. Results will be presented showing the impact of the AIRS profile data on water vapor and temperature fields, and on the resultant precipitation forecasts.
TRMM Precipitation Radar (PR) Level 2 Rainfall Rate and Profile Product (TRMM Product 2A25) V6
National Aeronautics and Space Administration — The TRMM Precipitation Radar (PR), the first of its kind in space, is an electronically scanning radar, operating at 13.8 GHz that measures the 3-D rainfall...
TRMM Precipitation Radar (PR) Level 2 Rainfall Rate and Profile Product (TRMM Product 2A25) V7
National Aeronautics and Space Administration — The TRMM Precipitation Radar (PR), the first of its kind in space, is an electronically scanning radar, operating at 13.8 GHz that measures the 3-D rainfall...
Macrophysical cloud properties simulated by two-moment microphysics
Baba, Y.
2016-12-01
Cloud-resolving model (CRM) is becoming useful tool for climate. Recently, two-moment cloud microphysics which additionally predicts number concentration of water species and thus realizes more flexible representation for cloud properties has been widely used in CRM. The two-moment representation is also suitable for long-range CRM simulation, since cloud-radiation interaction is affected by number concentration of cloud droplet through aerosol indirect effects. In spite of the advancement in microphysical modeling, cloud properties simulated by CRM is dependent on microphysical parameterization and the resulting properties remains unknown until model's sensitivity has been confirmed. In order to clarify dependence of microphysical parametezation on cloud macrophysical outcome, especially focusing on two-moment representation of cloud microphysics, sensitivity experiments were performed in two idealized experiments, i.e., squall line and radiative convective quasi-equilibrium. The former experiment showed that predicting number concentration of large ice water species was necessary for simulating more realistic precipitation trends. A distinct difference between strong convective and weak stratiform precipitations in squall line was found to be dependent on the microphysical parameterization. The latter experiments showed a consistent trends with that of the former experiment, i.e., prediction of number concentration of large ice water species affects long-range, macrophysical cloud properties such as resulting heat and water budget in cloud-radiation interaction, and the budgets were greatly controlled by the behaviors of large ice water species. The vertical profiles of cloud mass flux were different and it was found to be derived from production rate of ice water species which was affected by number concentration of ice water species. The present results indicate that macrophysics of cloud properties depend on behaviors of ice water species rather than liquid
Directory of Open Access Journals (Sweden)
R. Rivero Galán
1998-01-01
Full Text Available En el presente trabajo se brindan fórmulas y coeficientes para la determinación del momento de inercia a la torsión de una barrade perfil canal. Las fórmulas obtenidas se validan mediante la simulación de diferentes estructuras de uniones entre canales conel uso del método de los elementos finitos._______________________________________________________________________AbstractIn the paper are offered formulations and coefficients for the determination of the moment of inertia to the twist for a profilebar channel. The obtained formulations are validated through the simulation by the finite elements method of differentstructures of unions between channels.
Updating neutrino magnetic moment constraints
Directory of Open Access Journals (Sweden)
B.C. Cañas
2016-02-01
Full Text Available In this paper we provide an updated analysis of the neutrino magnetic moments (NMMs, discussing both the constraints on the magnitudes of the three transition moments Λi and the role of the CP violating phases present both in the mixing matrix and in the NMM matrix. The scattering of solar neutrinos off electrons in Borexino provides the most stringent restrictions, due to its robust statistics and the low energies observed, below 1 MeV. Our new limit on the effective neutrino magnetic moment which follows from the most recent Borexino data is 3.1×10−11μB at 90% C.L. This corresponds to the individual transition magnetic moment constraints: |Λ1|≤5.6×10−11μB, |Λ2|≤4.0×10−11μB, and |Λ3|≤3.1×10−11μB (90% C.L., irrespective of any complex phase. Indeed, the incoherent admixture of neutrino mass eigenstates present in the solar flux makes Borexino insensitive to the Majorana phases present in the NMM matrix. For this reason we also provide a global analysis including the case of reactor and accelerator neutrino sources, presenting the resulting constraints for different values of the relevant CP phases. Improved reactor and accelerator neutrino experiments will be needed in order to underpin the full profile of the neutrino electromagnetic properties.
National Aeronautics and Space Administration — This product contains global monthly means of surface precipitation rate, rain rate, convective surface precipitation rate and 28 vertical layers of hydrometeor...
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Vicente de P. S. de Oliveira
2005-09-01
Full Text Available As pesquisas sobre precipitação no Brasil têm-se restringido à previsão da lâmina total máxima ou da intensidade máxima provável, esta feita com base em séries históricas. Poucos trabalhos, no entanto, consideram o perfil correspondente a essas precipitações. A falta de modelos representativos tem forçado o uso daqueles desenvolvidos no exterior; contudo, os resultados obtidos demonstram, muitas vezes, que eles não representam adequadamente as condições climáticas típicas do Brasil. Objetivou-se, com o presente trabalho, detalhar complementarmente o desenvolvimento do modelo denominado CLIMABR, descrito por Oliveira et al. (2003, e mostrar sua aplicação para a geração do perfil instantâneo associado às séries sintéticas de precipitação, para as condições climáticas encontradas no Estado do Rio de Janeiro. Na série sintética gerada foram obtidos, para cada dia simulado, entre outros resultados, a duração dos eventos e os valores padronizados da intensidade máxima instantânea de precipitação e do tempo de sua ocorrência ao longo dos eventos. Os dois últimos valores obtidos no modelo foram utilizados para a obtenção do perfil de precipitação representado por uma função dupla exponencial, que foi ajustada a cada evento diário.The research about precipitation in Brazil has been restricted, most of time, to predict the maximum - total - or probable maximum intensity, this being done on the basis of historical series. Only few projects consider the corresponding profiles to these precipitations. The lack of representative models has forced the use of models developed abroad, despite the fact that the obtained results demonstrate, many times, was in inadequability to represent the typical climatic conditions in Brazil. The aim of the present work to detail complementarily to the development of the CLIMABR model, described by Oliveira et al. (2003, and show its application for instantaneous profile
Marciano, William J
2010-01-01
This book provides a self-contained description of the measurements of the magnetic dipole moments of the electron and muon, along with a discussion of the measurements of the fine structure constant, and the theory associated with magnetic and electric dipole moments. Also included are the searches for a permanent electric dipole moment of the electron, muon, neutron and atomic nuclei. The related topic of the transition moment for lepton flavor violating processes, such as neutrinoless muon or tauon decays, and the search for such processes are included as well. The papers, written by many o
Moment graphs and representations
DEFF Research Database (Denmark)
Jantzen, Jens Carsten
2012-01-01
Moment graphs and sheaves on moment graphs are basically combinatorial objects that have be used to describe equivariant intersectiion cohomology. In these lectures we are going to show that they can be used to provide a direct link from this cohomology to the representation theory of simple Lie ...
Schmüdgen, Konrad
2017-01-01
This advanced textbook provides a comprehensive and unified account of the moment problem. It covers the classical one-dimensional theory and its multidimensional generalization, including modern methods and recent developments. In both the one-dimensional and multidimensional cases, the full and truncated moment problems are carefully treated separately. Fundamental concepts, results and methods are developed in detail and accompanied by numerous examples and exercises. Particular attention is given to powerful modern techniques such as real algebraic geometry and Hilbert space operators. A wide range of important aspects are covered, including the Nevanlinna parametrization for indeterminate moment problems, canonical and principal measures for truncated moment problems, the interplay between Positivstellensätze and moment problems on semi-algebraic sets, the fibre theorem, multidimensional determinacy theory, operator-theoretic approaches, and the existence theory and important special topics of multidime...
Falewicz, Robert; Radziszewski, Krzysztof; Rudawy, Paweł; Berlicki, Arkadiusz
2017-10-01
We compare time variations of the Hα and X-ray emissions observed during the pre-impulsive and impulsive phases of the C1.1-class solar flare on 2013 June 21 with those of plasma parameters and synthesized X-ray emission from a 1D hydrodynamic numerical model of the flare. The numerical model was calculated assuming that the external energy is delivered to the flaring loop by nonthermal electrons (NTEs). The Hα spectra and images were obtained using the Multi-channel Subtractive Double Pass spectrograph with a time resolution of 50 ms. The X-ray fluxes and spectra were recorded by RHESSI. Pre-flare geometric and thermodynamic parameters of the model and the delivered energy were estimated using RHESSI data. The time variations of the X-ray light curves in various energy bands and those of the Hα intensities and line profiles were well correlated. The timescales of the observed variations agree with the calculated variations of the plasma parameters in the flaring loop footpoints, reflecting the time variations of the vertical extent of the energy deposition layer. Our result shows that the fast time variations of the Hα emission of the flaring kernels can be explained by momentary changes of the deposited energy flux and the variations of the penetration depths of the NTEs.
DEFF Research Database (Denmark)
Swann, Andrew Francis; Madsen, Thomas Bruun
2012-01-01
We introduce a notion of moment map adapted to actions of Lie groups that preserve a closed three-form. We show existence of our multi-moment maps in many circumstances, including mild topological assumptions on the underlying manifold. Such maps are also shown to exist for all groups whose second...... and third Lie algebra Betti numbers are zero. We show that these form a special class of solvable Lie groups and provide a structural characterisation. We provide many examples of multi-moment maps for different geometries and use them to describe manifolds with holonomy contained in G(2) preserved by a two...
González-Sprinberg, G. A.; Vidal, J.
2017-10-01
The τ lepton magnetic moment theoretical predictions and measurements are reviewed. While it is believed that such a high mass particle is a good candidate to show up new physics, this is not the case up to now. The magnetic moment of elementary fermions, and in particular the anomalous magnetic moment of the electron, had an historical impact both in relativistic quantum mechanics and in quantum field theories. Besides, many new physics models were discarded when confronted with these magnitudes. More recently, the discrepancy of the experiments and the theoretical predictions for the muon anomalous magnetic moment is still an open issue. For the τ lepton, instead, while the theoretical prediction is well known for the standard model and some new physics models, the data are very far of determining even its sign or the first figure. We will discuss the most important theoretical aspects of the τ magnetic moment, and also the current accepted measurements and future perspectives, in particular related to B-factories.
Pieters, Jurgen
2001-01-01
'Moments of Negotiation' offers the first book-length and indepth analysis of the New Historicist reading method, which the American Shakespeare-scolar Stephen Greenblatt introduced at the beginning of the 1980s. Ever since, Greenblatt has been hailed as the prime representative of this movement,
Three Moments in Jewish Philosophy
Stefan Goltzberg
2013-01-01
The purpose of this article is to offer a new periodization of Jewish philosophy and to reflect on the definition of Jewish philosophy. It will therefore deal with the characteristic style of each Jewish philosophy rather than with their content. I shall identify three moments in the history of Jewish philosophy: the Arab moment, the German moment, and the analytic moment; this last moment, largely unknown, will be studied more in depth. This paper does not aim to present an exhaustive panora...
Improving the Representation of Snow Crystal Properties Within a Single-Moment Microphysics Scheme
Molthan, Andrew L.; Petersen, Walter A.; Case, Jonathan L.; Dembek, S. R.
2010-01-01
As computational resources continue their expansion, weather forecast models are transitioning to the use of parameterizations that predict the evolution of hydrometeors and their microphysical processes, rather than estimating the bulk effects of clouds and precipitation that occur on a sub-grid scale. These parameterizations are referred to as single-moment, bulk water microphysics schemes, as they predict the total water mass among hydrometeors in a limited number of classes. Although the development of single moment microphysics schemes have often been driven by the need to predict the structure of convective storms, they may also provide value in predicting accumulations of snowfall. Predicting the accumulation of snowfall presents unique challenges to forecasters and microphysics schemes. In cases where surface temperatures are near freezing, accumulated depth often depends upon the snowfall rate and the ability to overcome an initial warm layer. Precipitation efficiency relates to the dominant ice crystal habit, as dendrites and plates have relatively large surface areas for the accretion of cloud water and ice, but are only favored within a narrow range of ice supersaturation and temperature. Forecast models and their parameterizations must accurately represent the characteristics of snow crystal populations, such as their size distribution, bulk density and fall speed. These properties relate to the vertical distribution of ice within simulated clouds, the temperature profile through latent heat release, and the eventual precipitation rate measured at the surface. The NASA Goddard, single-moment microphysics scheme is available to the operational forecast community as an option within the Weather Research and Forecasting (WRF) model. The NASA Goddard scheme predicts the occurrence of up to six classes of water mass: vapor, cloud ice, cloud water, rain, snow and either graupel or hail.
Molthan, Andrew L.
2010-01-01
High resolution weather forecast models with explicit prediction of hydrometeor type, size distribution, and fall speed may be useful in the development of precipitation retrievals, by providing representative characteristics of frozen hydrometeors. Several single or double-moment microphysics schemes are currently available within the Weather Research and Forecasting (WRF) model, allowing for the prediction of up to three ice species. Each scheme incorporates different assumptions regarding the characteristics of their ice classes, particularly in terms of size distribution, density, and fall speed. In addition to the prediction of hydrometeor content, these schemes must accurately represent the vertical profile of water vapor to account for possible attenuation, along with the size distribution, density, and shape characteristics of ice crystals that are relevant to microwave scattering. An evaluation of a particular scheme requires the availability of field campaign measurements. The Canadian CloudSat/CALIPSO Validation Project (C3VP) obtained measurements of ice crystal shapes, size distributions, fall speeds, and precipitation during several intensive observation periods. In this study, C3VP observations obtained during the 22 January 2007 synoptic-scale snowfall event are compared against WRF model output, based upon forecasts using four single-moment and two double-moment schemes available as of version 3.1. Schemes are compared against aircraft observations by examining differences in size distribution, density, and content. In addition to direct measurements from aircraft probes, simulated precipitation can also be converted to equivalent, remotely sensed characteristics through the use of the NASA Goddard Satellite Data Simulator Unit. Outputs from high resolution forecasts are compared against radar and satellite observations emphasizing differences in assumed crystal shape and size distribution characteristics.
Directory of Open Access Journals (Sweden)
Jennifer Yee
2017-09-01
Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the management of a precipitous birth in the emergency department (ED. The case is also appropriate for teaching of medical students and advanced practice providers, as well as reviewing the principles of crisis resource management, teamwork, and communication. Introduction: Patients with precipitous birth require providers to manage two patients simultaneously with limited time and resources. Crisis resource management skills will be tested once baby is delivered, and the neonate will require assessment for potential neonatal resuscitation. Objectives: At the conclusion of the simulation session, learners will be able to manage women who have precipitous deliveries, as well as perform neonatal assessment and management. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on precipitous birth management and neonatal evaluation.
Koontz, Laura
2014-01-01
Trichloroacetic acid (TCA) precipitation of proteins is commonly used to concentrate protein samples or remove contaminants, including salts and detergents, prior to downstream applications such as SDS-PAGE or 2D-gels. TCA precipitation denatures the protein, so it should not be used if the protein must remain in its folded state (e.g., if you want to measure a biochemical activity of the protein). © 2014 Elsevier Inc. All rights reserved.
McKenzie, T.R.
1960-09-13
A process is given for improving the precipitation of strontium from an aqueous phosphoric-acid-containing solution with nickel or cobalt ferrocyanide by simultaneously precipitating strontium or calcium phosphate. This is accomplished by adding to the ferrocyanide-containing solution calcium or strontium nitrate in a quantity to yield a concentration of from 0.004 to 0.03 and adjusting the pH of the solution to a value of above 8.
Redefining the political moment
Directory of Open Access Journals (Sweden)
James Arvanitakis
2011-07-01
Full Text Available On 16 February 2003, more than half a million people gathered in Sydney, Australia, as part of a global anti-war protest aimed at stopping the impending invasion of Iraq by the then US Administration. It is difficult to estimate how many millions marched on the coordinated protest, but it was by far the largest mobilization of a generation. Walking and chanting on the streets of Sydney that day, it seemed that a political moment was upon us. In a culture that rarely embraces large scale activism, millions around Australian demanded to be heard. The message was clear: if you do not hear us, we would be willing to bring down a government. The invasion went ahead, however, with the then Australian government, under the leadership of John Howard, being one of the loudest and staunchest supporters of the Bush Administrations drive to war. Within 18 months, anti-war activists struggled to have a few hundred participants take part in anti-Iraq war rallies, and the Howard Government was comfortably re-elected for another term. The political moment had come and gone, with both social commentators and many members of the public looking for a reason. While the conservative media was often the focus of analysis, this paper argues that in a time of late capitalism, the political moment is hollowed out by ‘Politics’ itself. That is to say, that formal political processes (or ‘Politics’ undermine the political practices that people participate in everyday (or ‘politics’. Drawing on an ongoing research project focusing on democracy and young people, I discuss how the concept of ’politics‘ has been destabilised and subsequently, the political moment has been displaced. This displacement has led to a re-definition of ‘political action’ and, I argue, the emergence of a different type of everyday politics.
On the effects of vertical air velocity on winter precipitation types
Directory of Open Access Journals (Sweden)
J. M. Thériault
2007-01-01
Full Text Available The various precipitation types formed within winter storms (such as snow, wet snow and freezing rain often lead to very hazardous weather conditions. These types of precipitation often occur during the passage of a warm front as a warm air mass ascends over a cold air mass. To address this issue further, we used a one-dimensional kinematic cloud model to simulate this gentle ascent (≤10 cm/s of warm air. The initial temperature profile has an above 0°C inversion, a lower subfreezing layer, and precipitation falls from above the temperature inversion. The cloud model is coupled to a double-moment microphysics scheme that simulates the production of various types of winter precipitation. The results are compared with those from a previous study carried out in still air. Based on the temporal evolution of surface precipitation, snow reaches the surface significantly faster than in still air whereas other precipitation types including freezing rain and ice pellets have a shorter duration. Overall, even weak background vertical ascent has an important impact on the precipitation reaching the surface, the time of the elimination of the melting layer, and also the evolution of the lower subfreezing layer.
Distributions on unbounded moment spaces and random moment sequences
Dette, Holger; Nagel, Jan
2012-01-01
In this paper we define distributions on moment spaces corresponding to measures on the real line with an unbounded support. We identify these distributions as limiting distributions of random moment vectors defined on compact moment spaces and as distributions corresponding to random spectral measures associated with the Jacobi, Laguerre and Hermite ensemble from random matrix theory. For random vectors on the unbounded moment spaces we prove a central limit theorem where the centering vecto...
National Aeronautics and Space Administration — The 2AGPROF (also known as, GPM GPROF (Level 2)) algorithm retrieves consistent precipitation and related science fields from the following GMI and partner passive...
Face recognition using Krawtchouk moment
Indian Academy of Sciences (India)
Feature extraction is one of the important tasks in face recognition. Moments are widely used feature extractor due to their superior discriminatory power and geometrical invariance. Moments generally capture the global features of the image. This paper proposes Krawtchouk moment for feature extraction in face recognition ...
Face recognition using Krawtchouk moment
Indian Academy of Sciences (India)
Abstract. Feature extraction is one of the important tasks in face recognition. Moments are widely used feature extractor due to their superior discriminatory power and geometrical invariance. Moments generally capture the global features of the image. This paper proposes Krawtchouk moment for feature extraction in face ...
Paul Callaghan luminous moments
Callaghan, Paul
2013-01-01
Acknowledged internationally for his ground-breaking scientific research in the field of magnetic resonance, Sir Paul Callaghan was a scientist and visionary with a rare gift for promoting science to a wide audience. He was named New Zealander of the Year in 2011. His death in early 2012 robbed New Zealand of an inspirational leader. Paul Callaghan: Luminous Moments brings together some of his most significant writing. Whether he describes his childhood in Wanganui, reflects on discovering the beauty of science, sets out New Zealand's future potential or discusses the experience of fa
Directory of Open Access Journals (Sweden)
Marc eWittmann
2011-10-01
Full Text Available It has been suggested that perception and action can be understood as evolving in temporal epochs or sequential processing units. Successive events are fused into units forming a unitary experience or ‘psychological present’. Studies have identified several temporal integration levels on different time scales which are fundamental for our understanding of behaviour and subjective experience. In recent literature concerning the philosophy and neuroscience of consciousness these separate temporal processing levels are not always precisely distinguished. Therefore, empirical evidence from psychophysics and neuropsychology on these distinct temporal processing levels is presented and discussed within philosophical conceptualizations of time experience. On an elementary level, one can identify a functional moment, a basic temporal building block of perception in the range of milliseconds that defines simultaneity and succession. Below a certain threshold temporal order is not perceived, individual events are processed as co-temporal. On a second level, an experienced moment, which is based on temporal integration of up to a few seconds, has been reported in many qualitatively different experiments in perception and action. It has been suggested that this segmental processing mechanism creates temporal windows that provide a logistical basis for conscious representation and the experience of nowness. On a third level of integration, continuity of experience is enabled by working-memory in the range of multiple seconds allowing the maintenance of cognitive operations and emotional feelings, leading to mental presence, a temporal window of an individual’s experienced presence.
Chen, Y-C; Tou, J C; Jaczynski, J
2007-11-01
Protein, lipid, and insolubles (bones, skin, scales, fins, insoluble protein, and more) were recovered from rainbow trout processing by-products by means of isoelectric solubilization/precipitation at basic pH and acidic pH. Isoelectric solubilization/precipitation of the trout processing by-products resulted in the recovery of protein that was higher (P acids (EAAs), non-EAAs, and total EAA/total AA ratio when compared to the processing by-products. Basic pH treatments yielded a higher (P acidic pH treatments. Nutritional quality of the recovered protein was high based on EAAs meeting the FAO/WHO/UNU recommendations for adults. The presence of omega-3 and omega-6 fatty acids (omega-3, omega-6 FAs) and the omega-3/omega-6 ratio in the recovered lipids were similar to the trout processing by-products, indicating that the pH treatments had no effect on these FAs. Ca and P contents of the processing by-products exceeded the recommended dietary allowances (RDA), but Fe and Mg did not. Basic pH treatments yielded protein with the lowest (P acidic pH. The isoelectric solubilization/precipitation of the processing by-products effectively removed minerals from the recovered protein without removal of the bones, skin, scales, fins, and so on, prior to processing. The results indicated that isoelectric solubilization/precipitation, particularly at basic pH, permitted recovery of high-quality protein and lipids from fish processing by-products for human food uses; also, the recovered insolubles may be used in animal feeds as a source of minerals.
National Aeronautics and Space Administration — Version 5 is the current version of the data set. Version 4 is no longer available and has been superseded by Version 5. The 2AGPROF (Goddard Profiling) algorithm...
National Aeronautics and Space Administration — Version 5 is the current version of the data set. Version 4 is no longer available and has been superseded by Version 5. The 2AGPROF (Goddard Profiling) algorithm...
2002-01-01
Experiment IS358 uses the intense and pure beams of copper isotopes provided by the ISOLDE RILIS (resonance ionization laser ion source). The isotopes are implanted and oriented in the low temperature nuclear orientation set-up NICOLE. Magnetic moments are measured by $\\beta$-NMR. Copper (Z=29), with a single proton above the proton-magic nickel isotopes provides an ideal testground for precise shell model calculations of magnetic moments and their experimental verification. In the course of our experiments we already determined the magnetic moments of $^{67}$Ni, $^{67}$Cu, $^{68g}$Cu, $^{69}$Cu and $^{71}$Cu which provide important information on the magicity of the N=40 subshell closure. In 2001 we plan to conclude our systematic investigations by measuring the magnetic moment of the neutron-deficient isotope $^{59}$Cu. This will pave the way for a subsequent study of the magnetic moment of $^{57}$Cu with a complementary method.
Directory of Open Access Journals (Sweden)
Sergey Pulinets
2012-04-01
Full Text Available
The analysis of energetic electron observations made by the DEMETER satellite reveals that radiation belt electron precipitation (RBEP bursts are observed in general several (~1-6 days before a large (M > 6.5 earthquake (EQ in the presence of broad band (~1-20 kHz VLF waves. The EBs show in general a relative peak-to-background flux increase usually < 100, they have a time duration of ~0.5 – 3 min, and their energy spectrum reach up to energies <~500 keV. The RBEP activity is observed as one, two or three EBs throughout a semi-orbit, depended on the magnetic field structure above the EQ epicenter. A statistical analysis has been made for earthquakes in Japan, which reveals a standard temporal variation of the number of EBs, which begins with an incremental rate several days before major earthquakes, and after a maximum, decreases so that the electron precipitation ceases above the epicenter. Some earthquake induced EBs were observed not only in the nightside ionosphere, but also in the dayside ionosphere.
Regional frequency analysis of extremes precipitations in Northern of Mozambique
Álvarez, M.; J. Puertas; Peña, E.
2016-01-01
[EN] Extreme precipitation events that occur over internal basins of Cabo Delgado (Northern Mozambique) often result in the occurrence of flood events with associated loss of life and infrastructure. This paper presents a study of regional frequency analysis of maximum daily precipitations based on the index flood procedure with estimated parameters by L-moments approach. Observed annual maximum daily precipitation series of 12 stations with records of more than 20 years were analyzed. The di...
Inquiry-Based Science: Turning Teachable Moments into Learnable Moments
Haug, Berit S.
2014-02-01
This study examines how an inquiry-based approach to teaching and learning creates teachable moments that can foster conceptual understanding in students, and how teachers capitalize upon these moments. Six elementary school teachers were videotaped as they implemented an integrated inquiry-based science and literacy curriculum in their classrooms. In this curriculum, science inquiry implies that students search for evidence in order to make and revise explanations based on the evidence found and through critical and logical thinking. Furthermore, the curriculum material is designed to address science key concepts multiple times through multiple modalities (do it, say it, read it, write it). Two types of teachable moments were identified: planned and spontaneous. Results suggest that the consolidation phases of inquiry, when students reinforce new knowledge and connect their empirical findings to theory, can be considered as planned teachable moments. These are phases of inquiry during which the teacher should expect, and be prepared for, student utterances that create opportunities to further student learning. Spontaneous teachable moments are instances when the teacher must choose to either follow the pace of the curriculum or adapt to the students' need. One implication of the study is that more teacher support is required in terms of how to plan for and effectively utilize the consolidation phases of inquiry.
Rosenfeld, D.; Krüger, M. L.; Andreae, M. O.; Kraemer, M.; Braga, R. C.; Machado, L.; Artaxo, P.
2015-12-01
The newly acquired possibility of retrieving from the SUOMI/NPP satellite the cloud base drop concentrations and updrafts made it possible to calculate cloud base vapor super saturation (S) and thus the CCN(S) over the GOAmazon domain, and validate it against surface and aircraft measurements. This was used to map the Manaus air pollution plume and observe its impact on cloud drop effective radius, precipitation forming processes and glaciation temperatures. These observations allow completing and extending the patchy picture obtained by the aircraft measurements over the full domain of interest. The methodology will be shown, as well as the main findings. By the time of the writing of this abstract we have already documented that during pristine conditions the CCN(S) is nearly double in the Manaus plume with respect to the background of ~200 cm-3 at S = 0.25 to 0.3%. The S of cloud base in the Manaus pollution plume is lower by about 0.05 to 0.1%. The cloud depth for initiation of warm rain increases by more than one km due to the decrease in cloud drop effective radius, as indicated by the increase in the isotherm level where it reaches the threshold of 14 micrometer. During smoky conditions, caused by distant biomass burning, the background CCN overwhelms the Manaus plume; CCN can exceed 1000 cm-3 at S Manaus pollution plume.
Image Recognition Using Modified Zernike Moments
Directory of Open Access Journals (Sweden)
Min HUANG
2014-03-01
Full Text Available Zernike moments are complex moments with the orthogonal Zernike polynomials as kernel function, compared with other moments; Zernike moments have greater advantages in image rotation and low noise sensitivity. Because of the Zernike moments have image rotation invariance, and can construct arbitrary high order moments, it can be used for target recognition. In this paper, the Zernike moment algorithm is improved, which makes it having scale invariance in the processing of digital image. At last, an application of the improved Zernike moments in image recognition is given.
Wilkins, S. G.; Lynch, K. M.; Billowes, J.; Binnersley, C. L.; Bissell, M. L.; Cocolios, T. E.; Goodacre, T. Day; de Groote, R. P.; Farooq-Smith, G. J.; Flanagan, K. T.; Franchoo, S.; Ruiz, R. F. Garcia; Gins, W.; Heylen, H.; Koszorús, Á.; Neyens, G.; Stroke, H. H.; Vernon, A. R.; Wendt, K. D. A.; Yang, X. F.
2017-09-01
The spectroscopic electric quadrupole moment of the neutron-deficient francium isotope 203Fr was measured by using high-resolution collinear resonance ionization spectroscopy (CRIS) at the CERN Isotope Separation On-Line Device (ISOLDE) facility. A remeasurement of the 207Fr quadrupole moment was also performed, resulting in a departure from the established literature value. A sudden increase in magnitude of the 203Fr quadrupole moment, with respect to the general trend in the region, points to an onset of static deformation at N =116 in the 87Fr isotopic chain. Calculation of the static and total deformation parameters show that the increase in static deformation only cannot account for the observed departure of its relative charge radius from the 82Pb chain.
Stochastic Generalized Method of Moments
Yin, Guosheng
2011-08-16
The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online. © 2011 American Statistical Association.
Moment Distributions of Phase Type
DEFF Research Database (Denmark)
Bladt, Mogens; Nielsen, Bo Friis
In this paper we prove that the class of distributions on the positive reals with a rational Laplace transform, also known as matrix-exponential distributions, is closed under formation of moment distributions. In particular, the results are hence valid for the well known class of phase-type dist......In this paper we prove that the class of distributions on the positive reals with a rational Laplace transform, also known as matrix-exponential distributions, is closed under formation of moment distributions. In particular, the results are hence valid for the well known class of phase...
Method of moments in electromagnetics
Gibson, Walton C
2007-01-01
Responding to the need for a clear, up-to-date introduction to the field, The Method of Moments in Electromagnetics explores surface integral equations in electromagnetics and presents their numerical solution using the method of moments (MOM) technique. It provides the numerical implementation aspects at a nuts-and-bolts level while discussing integral equations and electromagnetic theory at a higher level. The author covers a range of topics in this area, from the initial underpinnings of the MOM to its current applications. He first reviews the frequency-domain electromagnetic theory and t
Quiet Moment around the Campfire
Centers for Disease Control (CDC) Podcasts
2014-06-18
Byron Breedlove reads his essay, "Quiet Moment around the Campfire," about the art of Frederic Remington and the transmission of pathogens as frontiers expand. Created: 6/18/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 6/19/2014.
Measuring the Moment of Inertia
Lehmberg, George L.
1978-01-01
Two physics experiments are described, One, involving a laboratory cart accelerated along a level surface, examines the concept of inertial mass in translation and the other, using a solid cylinder, measures the moment of inertia of a wheel. Equations and illustrations are included. (MA)
Particle electric dipole-moments
Energy Technology Data Exchange (ETDEWEB)
Pendlebury, J.M. [Sussex Univ., Brighton (United Kingdom)
1997-04-01
The incentive to detect particle electric dipole-moments, as a window on time-reversal violation, remains undiminished. Efforts to improve the measurements for the neutron, the electron and some nuclei are still making rapid progress as more powerful experimental methods are brought to bear. A new measurement for the neutron at ILL is presented. (author). 7 refs.
Airborne particle monitoring by electrostatic precipitation
Robinson, J. C.; Stoneback, I. T.
1977-01-01
For qualitative analysis of atmospheric particulates by microscopy, the sampling device should preserve the particles in the state existing at the moment of capture. A collector is described that uses electrostatic precipitation to capture and disperse specimens on various substrates for direct insertion into microscopes. Sampling runs in various atmospheres are described. Micrographs are presented to show particle morphology and distribution on the substrates. Chemical identification by X-ray energy probe and electron diffraction is illustrated.
2006-01-01
One of the first events reconstructed in the Muon Drift Tubes, the Hadron Calorimeter and elements of the Silicon Tracker (TK) at 3 Tesla. The atmosphere in the CMS control rooms was electric. Everbody was at the helm for the first full-scale testing of the experiment. This was a crunch moment for the entire collaboration. On Tuesday, 22 August the magnet attained almost its nominal power of 4 Tesla! At the same moment, in a tiny improvised control room, the physicists were keyed up to test the entire detector system for the first time. The first cosmic ray tracks appeared on their screens in the week of 15 August. The tests are set to continue for several weeks more until the first CMS components are lowered into their final positions in the cavern.
Varble, Adam; Zipser, Edward J.; Fridland, Ann M.; Zhu, Ping; Ackerman, Andrew S.; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; Shipway, Ben; Williams, Christopher
2014-01-01
Ten 3-D cloud-resolving model (CRM) simulations and four 3-D limited area model (LAM) simulations of an intense mesoscale convective system observed on 23-24 January 2006 during the Tropical Warm Pool-International Cloud Experiment (TWP-ICE) are compared with each other and with observations and retrievals from a scanning polarimetric radar, colocated UHF and VHF vertical profilers, and a Joss-Waldvogel disdrometer in an attempt to explain a low bias in simulated stratiform rainfall. Despite different forcing methodologies, similar precipitation microphysics errors appear in CRMs and LAMs with differences that depend on the details of the bulk microphysics scheme used. One-moment schemes produce too many small raindrops, which biases Doppler velocities low, but produces rainwater contents (RWCs) that are similar to observed. Two-moment rain schemes with a gamma shape parameter (mu) of 0 produce excessive size sorting, which leads to larger Doppler velocities than those produced in one-moment schemes but lower RWCs. Two-moment schemes also produce a convective median volume diameter distribution that is too broad relative to observations and, thus, may have issues balancing raindrop formation, collision-coalescence, and raindrop breakup. Assuming a mu of 2.5 rather than 0 for the raindrop size distribution improves one-moment scheme biases, and allowing mu to have values greater than 0 may improve excessive size sorting in two-moment schemes. Underpredicted stratiform rain rates are associated with underpredicted ice water contents at the melting level rather than excessive rain evaporation, in turn likely associated with convective detrainment that is too high in the troposphere and mesoscale circulations that are too weak. A limited domain size also prevents a large, well-developed stratiform region like the one observed from developing in CRMs, although LAMs also fail to produce such a region.
Varble, Adam; Zipser, Edward J.; Fridlind, Ann M.; Zhu, Ping; Ackerman, Andrew S.; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; Shipway, Ben; Williams, Christopher
2014-12-01
Ten 3-D cloud-resolving model (CRM) simulations and four 3-D limited area model (LAM) simulations of an intense mesoscale convective system observed on 23-24 January 2006 during the Tropical Warm Pool-International Cloud Experiment (TWP-ICE) are compared with each other and with observations and retrievals from a scanning polarimetric radar, colocated UHF and VHF vertical profilers, and a Joss-Waldvogel disdrometer in an attempt to explain a low bias in simulated stratiform rainfall. Despite different forcing methodologies, similar precipitation microphysics errors appear in CRMs and LAMs with differences that depend on the details of the bulk microphysics scheme used. One-moment schemes produce too many small raindrops, which biases Doppler velocities low, but produces rainwater contents (RWCs) that are similar to observed. Two-moment rain schemes with a gamma shape parameter (μ) of 0 produce excessive size sorting, which leads to larger Doppler velocities than those produced in one-moment schemes but lower RWCs. Two-moment schemes also produce a convective median volume diameter distribution that is too broad relative to observations and, thus, may have issues balancing raindrop formation, collision-coalescence, and raindrop breakup. Assuming a μ of 2.5 rather than 0 for the raindrop size distribution improves one-moment scheme biases, and allowing μ to have values greater than 0 may improve excessive size sorting in two-moment schemes. Underpredicted stratiform rain rates are associated with underpredicted ice water contents at the melting level rather than excessive rain evaporation, in turn likely associated with convective detrainment that is too high in the troposphere and mesoscale circulations that are too weak. A limited domain size also prevents a large, well-developed stratiform region like the one observed from developing in CRMs, although LAMs also fail to produce such a region.
Improving the Representation of Snow Crystal Properties with a Single-Moment Mircophysics Scheme
Molthan, Andrew L.; Petersen, Walter A.; Case, Jonathan L.; Demek, Scott R.
2010-01-01
Single-moment microphysics schemes are utilized in an increasing number of applications and are widely available within numerical modeling packages, often executed in near real-time to aid in the issuance of weather forecasts and advisories. In order to simulate cloud microphysical and precipitation processes, a number of assumptions are made within these schemes. Snow crystals are often assumed to be spherical and of uniform density, and their size distribution intercept may be fixed to simplify calculation of the remaining parameters. Recently, the Canadian CloudSat/CALIPSO Validation Project (C3VP) provided aircraft observations of snow crystal size distributions and environmental state variables, sampling widespread snowfall associated with a passing extratropical cyclone on 22 January 2007. Aircraft instrumentation was supplemented by comparable surface estimations and sampling by two radars: the C-band, dual-polarimetric radar in King City, Ontario and the NASA CloudSat 94 GHz Cloud Profiling Radar. As radar systems respond to both hydrometeor mass and size distribution, they provide value when assessing the accuracy of cloud characteristics as simulated by a forecast model. However, simulation of the 94 GHz radar signal requires special attention, as radar backscatter is sensitive to the assumed crystal shape. Observations obtained during the 22 January 2007 event are used to validate assumptions of density and size distribution within the NASA Goddard six-class single-moment microphysics scheme. Two high resolution forecasts are performed on a 9-3-1 km grid, with C3VP-based alternative parameterizations incorporated and examined for improvement. In order to apply the CloudSat 94 GHz radar to model validation, the single scattering characteristics of various crystal types are used and demonstrate that the assumption of Mie spheres is insufficient for representing CloudSat reflectivity derived from winter precipitation. Furthermore, snow density and size
Moment Closure for the Stochastic Logistic Model
National Research Council Canada - National Science Library
Singh, Abhyudai; Hespanha, Joao P
2006-01-01
..., which we refer to as the moment closure function. In this paper, a systematic procedure for constructing moment closure functions of arbitrary order is presented for the stochastic logistic model...
Nuclear Quadrupole Moments and Nuclear Shell Structure
Townes, C. H.; Foley, H. M.; Low, W.
1950-06-23
Describes a simple model, based on nuclear shell considerations, which leads to the proper behavior of known nuclear quadrupole moments, although predictions of the magnitudes of some quadrupole moments are seriously in error.
Radar-Derived Quantitative Precipitation Estimation Based on Precipitation Classification
Directory of Open Access Journals (Sweden)
Lili Yang
2016-01-01
Full Text Available A method for improving radar-derived quantitative precipitation estimation is proposed. Tropical vertical profiles of reflectivity (VPRs are first determined from multiple VPRs. Upon identifying a tropical VPR, the event can be further classified as either tropical-stratiform or tropical-convective rainfall by a fuzzy logic (FL algorithm. Based on the precipitation-type fields, the reflectivity values are converted into rainfall rate using a Z-R relationship. In order to evaluate the performance of this rainfall classification scheme, three experiments were conducted using three months of data and two study cases. In Experiment I, the Weather Surveillance Radar-1988 Doppler (WSR-88D default Z-R relationship was applied. In Experiment II, the precipitation regime was separated into convective and stratiform rainfall using the FL algorithm, and corresponding Z-R relationships were used. In Experiment III, the precipitation regime was separated into convective, stratiform, and tropical rainfall, and the corresponding Z-R relationships were applied. The results show that the rainfall rates obtained from all three experiments match closely with the gauge observations, although Experiment II could solve the underestimation, when compared to Experiment I. Experiment III significantly reduced this underestimation and generated the most accurate radar estimates of rain rate among the three experiments.
Modelled Precipitation Over Greenland
National Aeronautics and Space Administration — This data set includes the annual total precipitation from 1985 to 1999 and monthly total precipitation from January 1985 to December 1999. The data is derived from...
Defining moments in leadership character development.
Bleich, Michael R
2015-06-01
Critical moments in life define one's character and clarify true values. Reflective leadership is espoused as an important practice for transformational leaders. Professional development educators can help surface and explore defining moments, strengthen leadership behavior with defining moments as a catalyst for change, and create safe spaces for leaders to expand their leadership capacity. Copyright 2015, SLACK Incorporated.
On the interpretation of the support moment
Hof, AL
2000-01-01
It has been suggested by Winter (J. Biomech. 13 (1980) 923-927) that the 'support moment', the sum of the sagittal extension moments, shows less variability in walking than any of the joint moments separately. A simple model is put forward to explain this finding. It is proposed to reformulate the
The Krein condition for the moment problem
DEFF Research Database (Denmark)
Pedersen, Henrik Laurberg
2005-01-01
In this paper, we describe a class of Wiener functionals that are `indeterminate by their moments', that is, whose distributions are not uniquely determined by their moments. In particular, it is proved that the integral of a geometric Brownian motion is indeterminate by its moments and, moreover...
Electric and Magnetic Dipole Moments
CERN. Geneva
2005-01-01
The stringent limit on the electric dipole moment of the neutron forced the issue on the strong CP-problem. The most elegant solution of which is the axion field proposed by Peccei and Quinn. The current limit on the QCD parameter theta coming from the limit on the neutron EDM is of order 10-10. I am going to describe the present status on the neutron EDM searches and further prospects on getting down to theta_qcd sensitivity of 10-13 with the new deuteron EDM in storage rings proposal. For completeness the current status and prospects of the muon g-2 experiment will also be given.
Moment-to-moment dynamics of ADHD behaviour
Directory of Open Access Journals (Sweden)
Aase Heidi
2005-08-01
learning long behavioural sequences may ultimately lead to deficient development of verbally governed behaviour and self control. The study represents a new approach to analyzing the moment-to-moment dynamics of behaviour, and provides support for the theory that reinforcement processes are altered in ADHD.
Predicting Robust Learning with the Visual Form of the Moment-by-Moment Learning Curve
Baker, Ryan S.; Hershkovitz, Arnon; Rossi, Lisa M.; Goldstein, Adam B.; Gowda, Sujith M.
2013-01-01
We present a new method for analyzing a student's learning over time for a specific skill: analysis of the graph of the student's moment-by-moment learning over time. Moment-by-moment learning is calculated using a data-mined model that assesses the probability that a student learned a skill or concept at a specific time during learning (Baker,…
Reinforced aerodynamic profile
DEFF Research Database (Denmark)
2010-01-01
The present invention relates to the prevention of deformations in an aerodynamic profile caused by lack of resistance to the bending moment forces that are created when such a profile is loaded in operation. More specifically, the invention relates to a reinforcing element inside an aerodynamic...
Bosilovich, Michael G.; Atlas, Robert (Technical Monitor)
2002-01-01
Precipitation recycling is defined as the amount of water that evaporates from a region that precipitates within the same region. This is also interpreted as the local source of water for precipitation. In this study, the local and remote sources of water for precipitation have been diagnosed through the use of passive constituent tracers that represent regional evaporative sources along with their transport and precipitation. We will discuss the differences between this method and the simpler bulk diagnostic approach to precipitation recycling. A summer seasonal simulation has been analyzed for the regional sources of the United States Great Plains precipitation. While the tropical Atlantic Ocean (including the Gulf of Mexico) and the local continental sources of precipitation are most dominant, the vertically integrated column of water contains substantial water content originating from the Northern Pacific Ocean, which is not precipitated. The vertical profiles of regional water sources indicate that local Great Plains source of water dominates the lower troposphere, predominantly in the PBL. However, the Pacific Ocean source is dominant over a large portion of the middle to upper troposphere. The influence of the tropical Atlantic Ocean is reasonably uniform throughout the column. While the results are not unexpected given the formulation of the model's convective parameterization, the analysis provides a quantitative assessment of the impact of local evaporation on the occurrence of convective precipitation in the GCM. Further, these results suggest that local source of water is not well mixed throughout the vertical column.
Measurements of DSD Second Moment Based on Laser Extinction
Lane, John E.; Jones, Linwood; Kasparis, Takis C.; Metzger, Philip
2013-01-01
Using a technique recently developed for estimating the density of surface dust dispersed during a rocket landing, measuring the extinction of a laser passing through rain (or dust in the rocket case) yields an estimate of the 2nd moment of the particle cloud, and rainfall drop size distribution (DSD) in the terrestrial meteorological case. With the exception of disdrometers, instruments that measure rainfall make in direct measurements of the DSD. Most common of these instruments are the rainfall rate gauge measuring the 1 1/3 th moment, (when using a D(exp 2/3) dependency on terminal velocity). Instruments that scatter microwaves off of hydrometeors, such as the WSR-880, vertical wind profilers, and microwave disdrometers, measure the 6th moment of the DSD. By projecting a laser onto a target, changes in brightness of the laser spot against the target background during rain, yield a measurement of the DSD 2nd moment, using the Beer-Lambert law. In order to detect the laser attenuation within the 8-bit resolution of most camera image arrays, a minimum path length is required, depending on the intensity of the rainfall rate. For moderate to heavy rainfall, a laser path length of 100 m is sufficient to measure variations in optical extinction using a digital camera. A photo-detector could replace the camera, for automated installations. In order to spatially correlate the 2nd moment measurements to a collocated disdrometer or tipping bucket, the laser's beam path can be reflected multiple times using mirrors to restrict the spatial extent of the measurement. In cases where a disdrometer is not available, complete DSD estimates can be produced by parametric fitting of DSD model to the 2nd moment data in conjunction with tipping bucket data. In cases where a disdrometer is collocated, the laser extinction technique may yield a significant improvement to insitu disdrometer validation and calibration strategies
Automated Moment Tensor Solution for the Southern California Seismic Network
Clinton, J. F.; Hauksson, E.; Solanki, K.
2004-12-01
Automatically generated moment tensor solutions have recently been added to the suite of real-time products produced by the Southern California Seismic Network (SCSN/CISN). The moment magnitude, Mw, and the moment tensor are available within minutes for all regional earthquakes that trigger the network with Ml>4.0, and in special cases for events between Ml 3.5-4.0. The method uses the 1-D Time-Domain INVerse Code (TDMT_INVC) software package developed by Doug Dreger, which is routinely used in real-time by the UC Berkeley Seismological Laboratory. Green's Functions are determined for various velocity profiles in Southern California, which are used in the inversion of observed three component broadband waveforms (10s-100s) for a number of stations. The duty seismologists will review the automatically generated solution before distribution. A web-interface has been developed to evaluate the quality of the automatic solution, and determine whether it meets the minimum requirements for an immediate distribution. Simple modifications to the stations selected for the inversion are possible, and the inversion can be re-run to optimise the solution. The Mw determined with this method will be the official SCSN/CISN Mw solution for the event. Comparisons of the moment tensors determined using this 1-D model are made with 3-D models generated for larger earthquakes in the Southern California to facilitate calibration of the automated algorithm.
Solving moment hierarchies for chemical reaction networks
Krishnamurthy, Supriya; Smith, Eric
2017-10-01
The study of chemical reaction networks (CRN’s) is a very active field. Earlier well-known results (Feinberg 1987 Chem. Enc. Sci. 42 2229, Anderson et al 2010 Bull. Math. Biol. 72 1947) identify a topological quantity called deficiency, for any CRN, which, when exactly equal to zero, leads to a unique factorized steady-state for these networks. No results exist however for the steady states of non-zero-deficiency networks. In this paper, we show how to write the full moment-hierarchy for any non-zero-deficiency CRN obeying mass-action kinetics, in terms of equations for the factorial moments. Using these, we can recursively predict values for lower moments from higher moments, reversing the procedure usually used to solve moment hierarchies. We show, for non-trivial examples, that in this manner we can predict any moment of interest, for CRN’s with non-zero deficiency and non-factorizable steady states.
Spermatogonium image recognition using Zernike moments.
Liyun, Wang; Hefei, Ling; Fuhao, Zou; Zhengding, Lu; Zhendi, Wang
2009-07-01
The automatic identification and classification of spermatogonium images is a very important issue in biomedical engineering research. This paper proposes a scheme for spermatogonium recognition, in which Zernike moments are used to represent image features. First of all, the mathematical morphology method is employed to extract the intact individual cell in every image, and then we normalize these binary images. Then, Zernike moments are calculated from these normalized images, followed by recognizing the spermatogonia through computing similarity of vectors composed with Zernike moments using Euclidean distance. Experimental results demonstrate that the proposed method, based on Zernike moments, outperforms two well-known methods, namely those based on Hu moments and boundary moments. This method has stronger distinguishing ability, showing better performance in discriminating cell images whether belong to the same cell.
Muon Dipole Moment Experiments Interpretation and Prospects
Feng, J L; Shadmi, Y; Feng, Jonathan L; Matchev, Konstantin T.; Shadmi, Yael
2001-01-01
We examine the prospects for discovering new physics through muon dipole moments. The current deviation in $g_{\\mu}-2$ may be due entirely to the muon's {\\em electric} dipole moment. We note that the precession frequency in the proposed BNL muon EDM experiment is also subject to a similar ambiguity, but this can be resolved by up-down asymmetry measurements. We then review the theoretical expectations for the muon's electric dipole moment in supersymmetric models.
Applications of Generalized Method of Moments Estimation
Wooldridge, Jeffrey M.
2001-01-01
I describe how the method of moments approach to estimation, including the more recent generalized method of moments (GMM) theory, can be applied to problems using cross section, time series, and panel data. Method of moments estimators can be attractive because in many circumstances they are robust to failures of auxiliary distributional assumptions that are not needed to identify key parameters. I conclude that while sophisticated GMM estimators are indispensable for complicated estimation ...
Image Description using Radial Associated Laguerre Moments
Directory of Open Access Journals (Sweden)
Bojun Pan
2015-08-01
Full Text Available This study proposes a new set of moment functions for describing gray-level and color images based on the associated Laguerre polynomials, which are orthogonal over the whole right-half plane. Moreover, the mathematical frameworks of radial associated Laguerre moments (RALMs and associated rotation invariants are introduced. The proposed radial Laguerre invariants retain the basic form of disc-based moments, such as Zernike moments (ZMs, pseudo-Zernike moments (PZMs, Fourier-Mellin moments (OFMMs, and so on. Therefore, the rotation invariants of RALMs can be easily obtained. In addition, the study extends the proposed moments and invariants defined in a gray-level image to a color image using the algebra of quaternion to avoid losing some significant color information. Finally, the paper verifies the feature description capacities of the proposed moment function in terms of image reconstruction and invariant pattern recognition accuracy. Experimental results confirmed that the associated Laguerre moments (ALMs perform better than orthogonal OFMMs in both noise-free and noisy conditions.
Directory of Open Access Journals (Sweden)
Jay Foster
2015-11-01
Full Text Available At least two recent collections of essays – Postmodernism and the Enlightenment (2001 and What’s Left of Enlightenment?: A Postmodern Question (2001 – have responded to postmodern critiques of Enlightenment by arguing that Enlightenment philosophes themselves embraced a number of post-modern themes. This essay situates Kant’s essay Was ist Aufklärung (1784 in the context of this recent literature about the appropriate characterization of modernity and the Enlightenment. Adopting an internalist reading of Kant’s Aufklärung essay, this paper observes that Kant is surprisingly ambivalent about who might be Enlightened and unspecific about when Enlightenment might be achieved. The paper argues that this is because Kant is concerned less with elucidating his concept of Enlightenment and more with characterizing a political condition that might provide the conditions for the possibility of Enlightenment. This paper calls this political condition modernity and it is achieved when civil order can be maintained alongside fractious and possibly insoluble public disagreement about matters of conscience, including the nature and possibility of Enlightenment. Thus, the audience for the Aufklärung essay is not the tax collector, soldier or clergyman, but rather the sovereign. Kant enjoins and advises the prince that discord and debate about matters of conscience need not entail any political unrest or upheaval. It is in this restricted (Pocockian sense that the Enlightenment essay is Kant’s Machiavellian moment.
Global Precipitation Measurement Poster
Azarbarzin, Art
2010-01-01
This poster presents an overview of the Global Precipitation Measurement (GPM) constellation of satellites which are designed to measure the Earth's precipitation. It includes the schedule of launches for the various satellites in the constellation, and the coverage of the constellation, It also reviews the mission capabilities, and the mission science objectives.
Molthan, Andrew L.
2011-01-01
Increases in computing resources have allowed for the utilization of high-resolution weather forecast models capable of resolving cloud microphysical and precipitation processes among varying numbers of hydrometeor categories. Several microphysics schemes are currently available within the Weather Research and Forecasting (WRF) model, ranging from single-moment predictions of precipitation content to double-moment predictions that include a prediction of particle number concentrations. Each scheme incorporates several assumptions related to the size distribution, shape, and fall speed relationships of ice crystals in order to simulate cold-cloud processes and resulting precipitation. Field campaign data offer a means of evaluating the assumptions present within each scheme. The Canadian CloudSat/CALIPSO Validation Project (C3VP) represented collaboration among the CloudSat, CALIPSO, and NASA Global Precipitation Measurement mission communities, to observe cold season precipitation processes relevant to forecast model evaluation and the eventual development of satellite retrievals of cloud properties and precipitation rates. During the C3VP campaign, widespread snowfall occurred on 22 January 2007, sampled by aircraft and surface instrumentation that provided particle size distributions, ice water content, and fall speed estimations along with traditional surface measurements of temperature and precipitation. In this study, four single-moment and two double-moment microphysics schemes were utilized to generate hypothetical WRF forecasts of the event, with C3VP data used in evaluation of their varying assumptions. Schemes that incorporate flexibility in size distribution parameters and density assumptions are shown to be preferable to fixed constants, and that a double-moment representation of the snow category may be beneficial when representing the effects of aggregation. These results may guide forecast centers in optimal configurations of their forecast models
A Unified Methodology for Computing Accurate Quaternion Color Moments and Moment Invariants.
Karakasis, Evangelos G; Papakostas, George A; Koulouriotis, Dimitrios E; Tourassis, Vassilios D
2014-02-01
In this paper, a general framework for computing accurate quaternion color moments and their corresponding invariants is proposed. The proposed unified scheme arose by studying the characteristics of different orthogonal polynomials. These polynomials are used as kernels in order to form moments, the invariants of which can easily be derived. The resulted scheme permits the usage of any polynomial-like kernel in a unified and consistent way. The resulted moments and moment invariants demonstrate robustness to noisy conditions and high discriminative power. Additionally, in the case of continuous moments, accurate computations take place to avoid approximation errors. Based on this general methodology, the quaternion Tchebichef, Krawtchouk, Dual Hahn, Legendre, orthogonal Fourier-Mellin, pseudo Zernike and Zernike color moments, and their corresponding invariants are introduced. A selected paradigm presents the reconstruction capability of each moment family, whereas proper classification scenarios evaluate the performance of color moment invariants.
Statistical Inference Based on L-Moments
Directory of Open Access Journals (Sweden)
Tereza Šimková
2017-03-01
Full Text Available To overcome drawbacks of central moments and comoment matrices usually used to characterize univariate and multivariate distributions, respectively, their generalization, termed L-moments, has been proposed. L-moments of all orders are defined for any random variable or vector with finite mean. L-moments have been widely employed in the past 20 years in statistical inference. The aim of the paper is to present the review of the theory of L-moments and to illustrate their application in parameter estimating and hypothesis testing. The problem of estimating the three-parameter generalized Pareto distribution’s (GPD parameters that is generally used in modelling extreme events is considered. A small simulation study is performed to show the superiority of the L-moment method in some cases. Because nowadays L-moments are often employed in estimating extreme events by regional approaches, the focus is on the key assumption of index-flood based regional frequency analysis (RFA, that is homogeneity testing. The benefits of the nonparametric L-moment homogeneity test are implemented on extreme meteorological events observed in the Czech Republic.
Closed forms and multi-moment maps
DEFF Research Database (Denmark)
Madsen, Thomas Bruun; Swann, Andrew Francis
We extend the notion of multi-moment map to geometries defined by closed forms of arbitrary degree. We give fundamental existence and uniqueness results and discuss a number of essential examples, including geometries related to special holonomy. For forms of degree four, multi-moment maps...
Teachable Moment: Google Earth Takes Us There
Williams, Ann; Davinroy, Thomas C.
2015-01-01
In the current educational climate, where clearly articulated learning objectives are required, it is clear that the spontaneous teachable moment still has its place. Authors Ann Williams and Thomas Davinroy think that instructors from almost any discipline can employ Google Earth as a tool to take advantage of teachable moments through the…
How to Introduce the Magnetic Dipole Moment
Bezerra, M.; Kort-Kamp, W. J. M.; Cougo-Pinto, M. V.; Farina, C.
2012-01-01
We show how the concept of the magnetic dipole moment can be introduced in the same way as the concept of the electric dipole moment in introductory courses on electromagnetism. Considering a localized steady current distribution, we make a Taylor expansion directly in the Biot-Savart law to obtain, explicitly, the dominant contribution of the…
Magnetic moment of single layer graphene rings
Margulis, V. A.; Karpunin, V. V.; Mironova, K. I.
2018-01-01
Magnetic moment of single layer graphene rings is investigated. An analytical expression for the magnetic moment as a function of the magnetic field flux through the one-dimensional quantum rings is obtained. This expression has the oscillation character. The oscillation period is equal to one flux quanta.
Closed forms and multi-moment maps
DEFF Research Database (Denmark)
Madsen, Thomas Bruun; Swann, Andrew Francis
2013-01-01
We extend the notion of multi-moment map to geometries defined by closed forms of arbitrary degree. We give fundamental existence and uniqueness results and discuss a number of essential examples, including geometries related to special holonomy. For forms of degree four, multi-moment maps are gu...
Catalyzed precipitation in aluminum
Mitlin, David
The work reported in Chapter 1 concerned the influence of Si on the precipitation of theta' (metastable Al2Cu) during the isothermal aging of Al-2Cu-1Si (wt. %). The binary alloys Al-2Cu and Al-1Si were studied for comparison. Only two precipitate phases were detected: pure Si in Al-Si and Al-Cu-Si, and theta' (metastable Al 2Cu) in Al-Cu and Al-Cu-Si. On aging the ternary, Si precipitates first, and provides heterogeneous sites to nucleate theta'. As a consequence, the density of theta' precipitates in Al-Cu-Si is much higher than in the binary Al-Cu. Also, the theta ' precipitates in the ternary alloy have lower aspect ratio (at given particle size) and lose coherence on their broad faces at a slower rate. The principal focus of Chapter 2 is to explain precipitation in Al-lat.%Si-lat%Ge. The microstructure is characterized using conventional and high resolution transmission electron microscopy, as well as energy dispersive X-ray spectroscopy. The first precipitates to come out of solid solution have a cube-cube orientation relationship with the matrix. High resolution TEM demonstrated that all the precipitates start out, and remain multiply twinned throughout the aging treatment. There is a variation in the stoichiometry of the precipitates, with the mean composition being Si-44.5at%Ge. It is also shown that in Al-Si-Ge it is not possible to achieve satisfactory hardness through a conventional heat treatment. This result is explained in terms of sluggish precipitation of the diamond-cubic Si-Ge phase coupled with particle coarsening. The purpose of Chapters 3 and 4 is to explain these properties in terms of the role that the Si-Ge additions have on modifying the conventional Al-Cu aging sequence. In both AlCu and AlCuSiGe the room temperature microstructure consists of both GP zones and theta″ precipitates. Upon aging at 190°C Al-Cu displays the well known precipitation sequence; the slow dissolution of GP zones and theta″ and the gradual formation of theta
Blurred image recognition by Legendre moment invariants.
Zhang, Hui; Shu, Huazhong; Han, Guoniu N; Coatrieux, Gouenou; Luo, Limin; Coatrieux, Jean Louis
2010-03-01
Processing blurred images is a key problem in many image applications. Existing methods to obtain blur invariants which are invariant with respect to centrally symmetric blur are based on geometric moments or complex moments. In this paper, we propose a new method to construct a set of blur invariants using the orthogonal Legendre moments. Some important properties of Legendre moments for the blurred image are presented and proved. The performance of the proposed descriptors is evaluated with various point-spread functions and different image noises. The comparison of the present approach with previous methods in terms of pattern recognition accuracy is also provided. The experimental results show that the proposed descriptors are more robust to noise and have better discriminative power than the methods based on geometric or complex moments.
National Oceanic and Atmospheric Administration, Department of Commerce — Hourly precipitation data tabulated under the Work Projects Administration (WPA), a New Deal program created to reduce unemployment during the Great Depression....
Is extreme precipitation changing?
Papalexiou, Simon Michael
2015-04-01
For most of the scientists climate change is a fact. Climate change implies changes not only on the behavior of the temperature but also on other climatic variables like the precipitation. The question raised in this study is whether or not the annual daily maximum precipitation has changed. In order to evaluate if this question can be answered, several thousands of precipitation records are analyzed from all over the globe. Initially the annual daily maxima time series are carefully formed and sequentially all possible trends are estimated in a moving window framework and for several interannual periods, e.g., from 10 years to 100 years. The aim is to estimate the difference between the percentage of increasing and decreasing trends in the annual daily maximum precipitation and assess if this difference indicates any specific pattern.
Storage Gage Precipitation Observations
National Oceanic and Atmospheric Administration, Department of Commerce — A storage gage is a precipitation gage that requires reading and maintenance only monthly or seasonal intervals. This library includes reports from such gages,...
Model reduction using the Vorobyev moment problem
Strakoš, Zdeněk
2009-07-01
Given a nonsingular complex matrix and complex vectors v and w of length N, one may wish to estimate the quadratic form w * A - 1 v, where w * denotes the conjugate transpose of w. This problem appears in many applications, and Gene Golub was the key figure in its investigations for decades. He focused mainly on the case A Hermitian positive definite (HPD) and emphasized the relationship of the algebraically formulated problems with classical topics in analysis - moments, orthogonal polynomials and quadrature. The essence of his view can be found in his contribution Matrix Computations and the Theory of Moments, given at the International Congress of Mathematicians in Zürich in 1994. As in many other areas, Gene Golub has inspired a long list of coauthors for work on the problem, and our contribution can also be seen as a consequence of his lasting inspiration. In this paper we will consider a general mathematical concept of matching moments model reduction, which as well as its use in many other applications, is the basis for the development of various approaches for estimation of the quadratic form above. The idea of model reduction via matching moments is well known and widely used in approximation of dynamical systems, but it goes back to Stieltjes, with some preceding work done by Chebyshev and Heine. The algebraic moment matching problem can for A HPD be formulated as a variant of the Stieltjes moment problem, and can be solved using Gauss-Christoffel quadrature. Using the operator moment problem suggested by Vorobyev, we will generalize model reduction based on matching moments to the non-Hermitian case in a straightforward way. Unlike in the model reduction literature, the presented proofs follow directly from the construction of the Vorobyev moment problem.
Moment of inertia in elliptical quantum dots
Serra, Llorenç; Puente, Antonio; Lipparini, Enrico
The moment of inertia of deformed quantum dots and its experimental relevance in relation to the dot spectroscopic features is theoretically investigated. A strong link to the low-energy orbital current mode that manifests in the magnetic dipole (M1) spectrum is stressed. The moment of inertia is obtained by solving the cranked Kohn-Sham equations within the local-spin-density approximation and the results discussed in comparison with the predictions of an analytical non-interacting model. The results as a function of deformation and size indicate that the existence of spin transitions in the dot ground state has an important effect on the moment of inertia.
A cohomological framework for homotopy moment maps
Frégier, Yaël; Laurent-Gengoux, Camille; Zambon, Marco
2015-11-01
Given a Lie group acting on a manifold M preserving a closed n + 1-form ω, the notion of homotopy moment map for this action was introduced in Fregier (0000), in terms of L∞-algebra morphisms. In this note we describe homotopy moment maps as coboundaries of a certain complex. This description simplifies greatly computations, and we use it to study various properties of homotopy moment maps: their relation to equivariant cohomology, their obstruction theory, how they induce new ones on mapping spaces, and their equivalences. The results we obtain extend some of the results of Fregier (0000).
Moment analysis of hadronic vacuum polarization
Energy Technology Data Exchange (ETDEWEB)
Rafael, Eduardo de
2014-09-07
I suggest a new approach to the determination of the hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon a{sub μ}{sup HVP} in lattice QCD. It is based on properties of the Mellin transform of the hadronic spectral function and their relation to the HVP self-energy in the Euclidean. I show how a{sub μ}{sup HVP} is very well approximated by a few moments associated to this Mellin transform and how these moments can be evaluated in lattice QCD, providing thus a series of tests when compared with the corresponding determinations using experimental data.
Binomial moment equations for stochastic reaction systems.
Barzel, Baruch; Biham, Ofer
2011-04-15
A highly efficient formulation of moment equations for stochastic reaction networks is introduced. It is based on a set of binomial moments that capture the combinatorics of the reaction processes. The resulting set of equations can be easily truncated to include moments up to any desired order. The number of equations is dramatically reduced compared to the master equation. This formulation enables the simulation of complex reaction networks, involving a large number of reactive species much beyond the feasibility limit of any existing method. It provides an equation-based paradigm to the analysis of stochastic networks, complementing the commonly used Monte Carlo simulations.
Moment analysis of hadronic vacuum polarization
Directory of Open Access Journals (Sweden)
Eduardo de Rafael
2014-09-01
Full Text Available I suggest a new approach to the determination of the hadronic vacuum polarization (HVP contribution to the anomalous magnetic moment of the muon aμHVP in lattice QCD. It is based on properties of the Mellin transform of the hadronic spectral function and their relation to the HVP self-energy in the Euclidean. I show how aμHVP is very well approximated by a few moments associated to this Mellin transform and how these moments can be evaluated in lattice QCD, providing thus a series of tests when compared with the corresponding determinations using experimental data.
Dynamical downscaling improves upon gridded precipitation products in the Sierra Nevada, California
Hughes, Mimi; Lundquist, Jessica D.; Henn, Brian
2017-04-01
Uncertainties in gridded and regional climate estimates of precipitation are large at high elevations, where observations are sparse and spatial variability is substantial. We explore these uncertainties for water year 2008 across California's Sierra Nevada in 10 datasets: 6 regional climate downscalings generated using the weather research and forecasting (WRF) model at convection-permitting resolution with differing lateral boundary conditions and microphysical parameterizations, and four gauge-based, interpolation-gridded precipitation datasets. Precipitation from these 10 datasets is evaluated against 95 snow pillows and a precipitation dataset inferred from stream gauges using a Bayesian inference method. During water year 2008, the gridded datasets tend to underestimate frozen precipitation on the windward slope of the Sierra Nevada, particularly in the vicinity of Yosemite National Park. The WRF simulations with single-moment microphysics tend to overestimate precipitation throughout much of the region, whereas the WRF simulations with double-moment microphysics tend to better agree with both the snow pillows and inferred precipitation estimates, although they somewhat overestimate the windward/leeside precipitation contrast in the northern Sierra Nevada. WRF simulations, in particular those with single-moment microphysics, better distinguish spatial patterns of wet-versus-dry pillows and watersheds over the water year than the gridded estimates. Our results suggest treating gauge-based datasets as `truth' may give a misleading representation of model accuracy, since these gauge-based datasets often have issues of their own.
Determining and correcting "moment bias" in gradient polymer elution chromatography.
Striegel, André M
2003-05-09
Gradient polymer elution chromatography (GPEC) is rapidly becoming the analytical method of choice for determining the chemical composition distribution (CCD) of synthetic polymers. GPEC can be performed in traditional (strict precipitation-redissolution mechanism) or interactive (normal- and reversed-phase) modes, and results may be qualitative, semi-quantitative, or fully quantitative. Quantitative approaches have thus far relied on colligative or end group techniques for determining the values of standards used in constructing the GPEC calibration curve. While the values obtained from said methods are number-averages, they are assigned to the peak apexes of the standards (i.e. assigned as peak averages). This creates a determinate error in the quantitation, referred to herein as "moment bias". In this paper we determine moment bias for a series of styrene-acrylonitrile (SAN) copolymers, where the distribution and averages of the AN% have been measured using normal-phase (NP) GPEC. We also correct for the effect via statistical treatment of the chromatographic data.
Earth's magnetic moment during geomagnetic reversals
Sokoloff, D. D.
2017-11-01
The behavior of the dipole magnetic moment of the geomagnetic field during the reversals is considered. By analogy with the reversals of the magnetic field of the Sun, the scenario is suggested in which during the reversal the mean dipole moment becomes zero, whereas the instantaneous value of the dipole magnetic moment remains nonzero and the corresponding vector rotates from the vicinity of one geographical pole to the other. A thorough discussion concerning the definition of the mean magnetic moment, which is used in this concept, is presented. Since the behavior of the geomagnetic field during the reversal is far from stationary, the ensemble average instead of the time average has to be considered.
Nonredundant Single-Gimbaled Control Moment Gyroscopes
2012-04-01
p. 79. [3] Kennel , H. F., “Steering Law for Parallel Mounted Double-Gimbaled Control Moment Gyros,” NASATM-X-64930, 1975, p. 34. [4] Colburn, B. K...NASATM-X-64926, 1975. [6] Kennel , H. F., “Steering Law for Parallel Mounted Double-Gimbaled Control Moment Gyros,” NASATM-X-82390, 1981, p. 22. Fig. 16
Variational approach to the moment of inertia
Energy Technology Data Exchange (ETDEWEB)
Stringari, S.; Lipparini, E.
1980-08-01
We derive an approximate expression for the moment of inertia theta in the framework of the cranked Hartree-Fock theory. Our method allows for a detailed study of the role of spin-orbit and two-body nuclear potentials. In particular it is shown that in /sup 20/Ne the two-body interaction lowers by 30% the rigid value of theta. The irrotational and rigid values for the moment of inertia are obtained as special cases of the present approach.
Maximum Entropy Moment Systems and Galilean Invariance
Junk, Michael; Unterreiter, Andreas
2001-01-01
In this article, we investigate the maximum entropy moment closure in gas dynamics. We show that the usual choice of polynomial weight functions may lead to hyperbolic systems with an unpleasant state space: equilibrium states are boundary points with possibly singular fluxes. In order to avoid singularities, the necessary arises to find weight functions which growing sub-quadratically at infinity. Unfortunately, this requirement leads to a conflict with Galilean invariance of the moment syst...
Link between chips and cutting moments evolution
Cahuc, Olivier; Gérard, Alain; 10.4028/WWW.scientific.net/AMR.423.89
2012-01-01
The better understanding of the material cutting process has been shown with the benefit of the forces and moments measurement since some years ago. In paper, simultaneous six mechanical components and chip orientation measurements were realized during turning tests. During these tests, the influence of the depth of cut or feed rate has been observed and a link between the chip orientation and the moment vector orientation or the central axis characteristics has been shown.
1998-05-01
illustrates how the appearance of a stellar image at the focal plane is fully controllable. Fast and thorough optical adjustment ensures the best possible optical quality at all times . 9. Image Quality of the VLT This diagram demonstrates that First Light specifications have been fully met and, more impressively, that the actual VLT performance is sometimes already within the more stringent specifications that were expected to be fulfilled only three years from now. The final steps before "First Light" The final, critical testing phase commenced with the installation of the 8.2-m primary (at that time still uncoated) Zerodur mirror and 1.1-m secondary Beryllium mirror during the second half of April. The optics were then gradually brought into position during carefully planned, successive adjustments. Due to the full integration of an advanced, active control system into the VLT concept, this delicate process went amazingly fast, especially when compared to other ground-based telescopes. It included a number of short test exposures in early May, first with the Guide Camera that is used to steer the telescope. Later, some exposures were made with the Test Camera mounted just below the main mirror at the Cassegrain Focus, in a central space inside the mirror cell. It will continue to be used during the upcoming Commissioning Phase, until the first major instruments (FORS and ISAAC) are attached to the UT1, later in 1998. The 8.2-m mirror was successfully aluminized at the Paranal Mirror Coating facility on May 20 and was reattached to the telescope tube the day thereafter, cf. ESO PR Photos 13a-e/98 and ESO PR Photos 14a-i/98. Further test exposures were then made to check the proper functioning of the telescope mechanics, optics and electronics. This has lead up to the moment of First Light , i.e. the time when the telescope is considered able to produce the first, astronomically useful images. Despite an intervening spell of bad atmospheric conditions, this important event
Measurement of magnetic moment via optical transmission
Heidsieck, Alexandra; Schmid, Daniel; Gleich, Bernhard
2016-03-01
The magnetic moment of nanoparticles is an important property for drug targeting and related applications as well as for the simulation thereof. However, the measurement of the magnetic moment of nanoparticles, nanoparticle-virus-complexes or microspheres in solution can be difficult and often yields unsatisfying or incomparable results. To measure the magnetic moment, we designed a custom measurement device including a magnetic set-up to observe nanoparticles indirectly via light transmission in solution. We present a simple, cheap device of manageable size, which can be used in any laboratory as well as a novel evaluation method to determine the magnetic moment of nanoparticles via the change of the optical density of the particle suspension in a well-defined magnetic gradient field. In contrast to many of the established measurement methods, we are able to observe and measure the nanoparticle complexes in their natural state in the respective medium. The nanoparticles move along the magnetic gradient and thereby away from the observation point. Due to this movement, the optical density of the fluid decreases and the transmission increases over time at the measurement location. By comparing the measurement with parametric simulations, we can deduce the magnetic moment from the observed behavior.
Benalcazar, Wladimir A.; Bernevig, B. Andrei; Hughes, Taylor L.
2017-12-01
We extend the theory of dipole moments in crystalline insulators to higher multipole moments. As first formulated in Benalcazar et al. [Science 357, 61 (2017), 10.1126/science.aah6442], we show that bulk quadrupole and octupole moments can be realized in crystalline insulators. In this paper, we expand in great detail the theory presented previously [Benalcazar et al., Science 357, 61 (2017), 10.1126/science.aah6442] and extend it to cover associated topological pumping phenomena, and a class of three-dimensional (3D) insulator with chiral hinge states. We start by deriving the boundary properties of continuous classical dielectrics hosting only bulk dipole, quadrupole, or octupole moments. In quantum mechanical crystalline insulators, these higher multipole bulk moments manifest themselves by the presence of boundary-localized moments of lower dimension, in exact correspondence with the electromagnetic theory of classical continuous dielectrics. In the presence of certain symmetries, these moments are quantized, and their boundary signatures are fractionalized. These multipole moments then correspond to new symmetry-protected topological phases. The topological structure of these phases is described by "nested" Wilson loops, which we define. These Wilson loops reflect the bulk-boundary correspondence in a way that makes evident a hierarchical classification of the multipole moments. Just as a varying dipole generates charge pumping, a varying quadrupole generates dipole pumping, and a varying octupole generates quadrupole pumping. For nontrivial adiabatic cycles, the transport of these moments is quantized. An analysis of these interconnected phenomena leads to the conclusion that a new kind of Chern-type insulator exists, which has chiral, hinge-localized modes in 3D. We provide the minimal models for the quantized multipole moments, the nontrivial pumping processes, and the hinge Chern insulator, and describe the topological invariants that protect them.
The Global Precipitation Mission
Braun, Scott; Kummerow, Christian
2000-01-01
The Global Precipitation Mission (GPM), expected to begin around 2006, is a follow-up to the Tropical Rainfall Measuring Mission (TRMM). Unlike TRMM, which primarily samples the tropics, GPM will sample both the tropics and mid-latitudes. The primary, or core, satellite will be a single, enhanced TRMM satellite that can quantify the 3-D spatial distributions of precipitation and its associated latent heat release. The core satellite will be complemented by a constellation of very small and inexpensive drones with passive microwave instruments that will sample the rainfall with sufficient frequency to be not only of climate interest, but also have local, short-term impacts by providing global rainfall coverage at approx. 3 h intervals. The data is expected to have substantial impact upon quantitative precipitation estimation/forecasting and data assimilation into global and mesoscale numerical models. Based upon previous studies of rainfall data assimilation, GPM is expected to lead to significant improvements in forecasts of extratropical and tropical cyclones. For example, GPM rainfall data can provide improved initialization of frontal systems over the Pacific and Atlantic Oceans. The purpose of this talk is to provide information about GPM to the USWRP (U.S. Weather Research Program) community and to discuss impacts on quantitative precipitation estimation/forecasting and data assimilation.
Precipitation Reconstruction (PREC)
National Oceanic and Atmospheric Administration, Department of Commerce — The PREC data set is an analysis of monthly precipitation constructed on a 2.5(o)lat/lon grid over the global for the period from 1948 to the present. The land...
Pengenalan Pose Tangan Menggunakan HuMoment
Directory of Open Access Journals (Sweden)
Dina Budhi Utami
2017-02-01
Full Text Available Computer vision yang didasarkan pada pengenalan bentuk memiliki banyak potensi dalam interaksi manusia dan komputer. Pose tangan dapat dijadikan simbol interaksi manusia dengan komputer seperti halnya pada penggunaan berbagai pose tangan pada bahasa isyarat. Berbagai pose tangan dapat digunakan untuk menggantikan fungsi mouse, untuk mengendalikan robot, dan sebagainya. Penelitian ini difokuskan pada pembangunan sistem pengenalan pose tangan menggunakan HuMoment. Proses pengenalan pose tangan dimulai dengan melakukan segmentasi citra masukan untuk menghasilkan citra ROI (Region of Interest yaitu area telapak tangan. Selanjutnya dilakukan proses deteksi tepi. Kemudian dilakukan ekstraksi nilai HuMoment. Nilai HuMoment dikuantisasikan ke dalam bukukode yang dihasilkan dari proses pelatihan menggunakan K-Means. Proses kuantisasi dilakukan dengan menghitung nilai Euclidean Distance terkecil antara nilai HuMomment citra masukan dan bukukode. Berdasarkan hasil penelitian, nilai akurasi sistem dalam mengenali pose tangan adalah 88.57%.
The anomalous magnetic moment of the muon
Jegerlehner, Friedrich
2017-01-01
This research monograph covers extensively the theory of the muon anomalous magnetic moment and provides estimates of the theoretical uncertainties. The muon anomalous magnetic moment is one of the most precisely measured quantities in elementary particle physics and provides one of the most stringent tests of relativistic quantum field theory as a fundamental theoretical framework. It allows for an extremely precise check of the standard model of elementary particles and of its limitations. This book reviews the present state of knowledge of the anomalous magnetic moment a=(g-2)/2 of the muon. Recent experiments at the Brookhaven National Laboratory now reach the unbelievable precision of 0.5 parts per million, improving the accuracy of previous g-2 experiments at CERN by a factor of 14. In addition, quantum electrodynamics and electroweak and hadronic effects are reviewed. Since non-perturbative hadronic effects play a key role for the precision test, their evaluation is described in detail. Perspectives fo...
A corrector for spacecraft calculated electron moments
Directory of Open Access Journals (Sweden)
J. Geach
2005-03-01
Full Text Available We present the application of a numerical method to correct electron moments calculated on-board spacecraft from the effects of potential broadening and energy range truncation. Assuming a shape for the natural distribution of the ambient plasma and employing the scalar approximation, the on-board moments can be represented as non-linear integral functions of the underlying distribution. We have implemented an algorithm which inverts this system successfully over a wide range of parameters for an assumed underlying drifting Maxwellian distribution. The outputs of the solver are the corrected electron plasma temperature Te, density Ne and velocity vector Ve. We also make an estimation of the temperature anisotropy A of the distribution. We present corrected moment data from Cluster's PEACE experiment for a range of plasma environments and make comparisons with electron and ion data from other Cluster instruments, as well as the equivalent ground-based calculations using full 3-D distribution PEACE telemetry.
Magnetic Moment Distribution in Layered Materials
Nicholson, D. M. C.; Zhang, X.-G.; Wang, Y.; Shelton, W. A.; Butler, W. H.; Stocks, G. M.; MacLaren, J. M.
1996-03-01
Thin layers of magnetic material surrounded by non-magnetic layers display a reduced moment per atom relative to the bulk magnetic material. Plots of sturation magnetization versus magnetic layer thickness can be explained in terms of magnetically dead layers at interfaces. First principles calculations indicate a more complex distribution of magnetic moments. Moment distributions calculated in the local density approximation restricted to colinear spins and with unrestricted spin orientations will be presented for Cu/Ni/Cu, Cu/permalloy/Cu, and Mo/Ni/Mo structures. Work supported by Division of Materials Science, the Mathematical Information and Computational Science Division of the Office of Computational Technology Research, and by the Assistant Secretary of Defence Programs, Technology Management Group, Technology Transfer Initiative, US DOE under subcontract DEAC05-84OR21400 with Martin-Marietta Energy Systems, Inc.
Spin and orbital moments in actinide compounds
DEFF Research Database (Denmark)
Lebech, B.; Wulff, M.; Lander, G.H.
1991-01-01
The extended spatial distribution of both the transition-metal 3d electrons and the actinide 5f electrons results in a strong interaction between these electron states when the relevant elements are alloyed. A particular interesting feature of this hybridization, which is predicted by single-electron...... band-structure calculations, is that the orbital moments of the actinide 5f electrons are considerably reduced from the values anticipated by a simple application of Hund's rules. To test these ideas, and thus to obtain a measure of the hybridization, we have performed a series of neutron scattering...... experiments designed to determine the magnetic moments at the actinide and transition-metal sublattice sites in compounds such as UFe2, NpCo2, and PuFe2 and to separate the spin and orbital components at the actinide sites. The results show, indeed, that the ratio of the orbital to spin moment is reduced...
Magnetic moment nonconservation in magnetohydrodynamic turbulence models.
Dalena, S; Greco, A; Rappazzo, A F; Mace, R L; Matthaeus, W H
2012-07-01
The fundamental assumptions of the adiabatic theory do not apply in the presence of sharp field gradients or in the presence of well-developed magnetohydrodynamic turbulence. For this reason, in such conditions the magnetic moment μ is no longer expected to be constant. This can influence particle acceleration and have considerable implications in many astrophysical problems. Starting with the resonant interaction between ions and a single parallel propagating electromagnetic wave, we derive expressions for the magnetic moment trapping width Δμ (defined as the half peak-to-peak difference in the particle magnetic moments) and the bounce frequency ω(b). We perform test-particle simulations to investigate magnetic moment behavior when resonance overlapping occurs and during the interaction of a ring-beam particle distribution with a broadband slab spectrum. We find that the changes of magnetic moment and changes of pitch angle are related when the level of magnetic fluctuations is low, δB/B(0) = (10(-3),10(-2)), where B(0) is the constant and uniform background magnetic field. Stochasticity arises for intermediate fluctuation values and its effect on pitch angle is the isotropization of the distribution function f(α). This is a transient regime during which magnetic moment distribution f(μ) exhibits a characteristic one-sided long tail and starts to be influenced by the onset of spatial parallel diffusion, i.e., the variance grows linearly in time as in normal diffusion. With strong fluctuations f(α) becomes completely isotropic, spatial diffusion sets in, and the f(μ) behavior is closely related to the sampling of the varying magnetic field associated with that spatial diffusion.
Multipeakons and the Classical Moment Problem
Beals, R; Szmigielski, J; Beals, Richard
1999-01-01
Classical results of Stieltjes are used to obtain explicit formulas for the peakon-antipeakon solutions of the Camassa-Holm equation. The closed form solution is expressed in terms of the orthogonal polynomials of the related classical moment problem. It is shown that collisions occur only in peakon-antipeakon pairs, and the details of the collisions are analyzed using results {}from the moment problem. A sharp result on the steepening of the slope at the time of collision is given. Asymptotic formulas are given, and the scattering shifts are calculated explicitly
Moment distributions of phase-type
DEFF Research Database (Denmark)
Bladt, Mogens; Nielsen, Bo Friis
2012-01-01
of the age an residual life-time, is also phase-type distributed. Moreover, we give some explicit representations. The spread is known to have a first order moment distribution. If X is a positive random variable and ?i is its i'th moment, then the function fi(x) = xif(x)/?i is a density function......-normal, Pareto and gamma distributions. We provide explicit representations for both the matrix-exponential class and for the phase-type distributions, where the latter class may also use the former representations, but for various reasons it is desirable to establish a phase-type representation when dealing...
Duality violations in τ hadronic spectral moments
Boito, D. R.; Catà, O.; Golterman, M.; Jamin, M.; Maltman, K.; Osborne, J.; Peris, S.
2011-09-01
Evidence is presented for the necessity of including duality violations in a consistent description of spectral function moments employed in the precision determination of α from τ decay. A physically motivated ansatz for duality violations in the spectral functions enables us to perform fits to spectral moments employing both pinched and unpinched weights. We describe our analysis strategy and provide some preliminary findings. Final numerical results await completion of an ongoing re-determination of the ALEPH covariance matrices incorpo-rating correlations due to the unfolding procedure which are absent from the currently posted versions. To what extent this issue affects existing analyses and our own work will require further study.
DEFF Research Database (Denmark)
Pedersen, Preben Terndrup; Jensen, Jørgen Juncher
2009-01-01
A simple but rational procedure for prediction of extreme wave-induced hull girder bending moment is presented. The procedure takes into account main ship hull characteristics such as: length, breadth, draught, block coefficient, bow flare coefficient, forward speed and hull flexibility. The wave......-induced loads are evaluated for specific operational profiles. Non-linearity in the wave bending moment is modeled using results derived from a second-order strip theory and water entry solutions for wedge type sections. Hence, bow flare slamming is accounted for through a momentum type of approach......-linear strip theory calculations and supplemented with new closed form results for the hogging bending moment. Focus is on the extreme hull girder hogging bending moment. Due to the few input parameters this procedure can be used to estimate the wave-induced bending moments at the conceptual design phase...
Empirical meaning of DTM multifractal parameters in the precipitation context
Portilla Farfan, Freddy; Valencia, Jose Luis; Villeta, Maria; Tarquis, Ana M.; Saa-Requejo, Antonio
2015-04-01
The main objective of this research is to interpret the multifractal parameters in the case of precipitation series from an empirical approach. In order to do so nineteen precipitation series were generated with a daily precipitation simulator derived from year and month estimations and considering the classical statistics, used commonly in hydrology studies, from actual data of four Spanish rain gauges located in a gradient from NW to SE. For all generated series the multifractal parameters were estimated following the technique DTM (Double Trace Moments) developed by Lavalle et al. (1993) and the variations produced considered. The results show the following conclusions: 1. The intermittency, C1, increases when precipitation is concentrating for fewer days, making it more variable, or when increasing its concentration on maximum monthly precipitation days, while it is not affected due to the modification in the variability in the number of days rained. 2. Multifractility, α, increases with the number of rainy days and the variability of the precipitation, yearly as well as monthly, as well as with the concentration of precipitation on the maximum monthly precipitation day. 3. The maximum probable singularity, γs, increases with the concentration of rain on the day of the maximum monthly precipitation and the variability in yearly and monthly level. 4. The non-conservative degree, H, depends on the number of rainy days that appear on the series and secondly on the general variability of the rain. References Lavallée D., S. Lovejoy, D. Schertzer and P. Ladoy, 1993. Nonlinear variability and landscape topography: analysis and simulation. In: Fractals in Geography (N. Lam and L. De Cola, Eds.) Prentice Hall, Englewood Cliffs, 158-192.
Multidistortion-invariant image recognition with radial harmonic Fourier moments.
Ren, Haiping; Ping, Ziliang; Bo, Wurigen; Wu, Wenkai; Sheng, Yunlong
2003-04-01
We propose radial harmonic Fourier moments, which are shifting, scaling, rotation, and intensity invariant. Compared with Chebyshev-Fourier moments, the new moments have superior performance near the origin and better ability to describe small images in terms of image-reconstruction errors and noise sensitivity. A multidistortion-invariant pattern-recognition experiment was performed with radial harmonic Fourier moments.
Optimization of the rapping process of an intermittent electrostatic precipitator
Miloua, F.; Tilmatine, A.; Gouri, R.; Kadous, N.; Dascalescu, L.
2008-01-01
Intermittent operation mode is specific to electrostatic precipitators (ESP) used in workshops where the polluting product is produced in a discontinuous way. The rapping system is necessary in order to ensure a continuous and effective operation of a dry electrostatic precipitator, but causes at the same time, a problem of re-entrainment of dust and thus the degradation of filtration efficiency. The objective of this paper is to propose a procedure based on the methodology of experimental designs (Tagushi's Methodology) aiming at optimizing the rapping process; it consists to determine optimal values of rapping, i.e. the moment, the position and the force of rapping. Several “one-factor-at-a-time" experimental designs followed by a Full Factorial design, made it possible to model the process and to analyze interactions between the factors. The experiments were carried out on a laboratory experimental device which simulates an industrial precipitator with intermittent operation.
Moments, Mixed Methods, and Paradigm Dialogs
Denzin, Norman K.
2010-01-01
I reread the 50-year-old history of the qualitative inquiry that calls for triangulation and mixed methods. I briefly visit the disputes within the mixed methods community asking how did we get to where we are today, the period of mixed-multiple-methods advocacy, and Teddlie and Tashakkori's third methodological moment. (Contains 10 notes.)
Using Aha! Moments to Understand Leadership Theory
Moore, Lori L.; Lewis, Lauren J.
2012-01-01
As Huber (2002) noted, striving to understand how leadership is taught and learned is both a challenge and an opportunity facing leadership educators. This article describes the "Leadership Aha! Moment" assignment used in a leadership theory course to help students recognize the intersection of leadership theories and their daily lives while…
Anomalous magnetic moment and Compton wavelength
Heyrovska, Raji
2004-01-01
The relativistic and quantum theoretical explanations of the magnetic moment anomaly of the electron (or proton) show that it is a complicated function of the fine structure constant. In this work, a simple non-relativistic approach shows that the translational motion of the particle during its spin is responsible for the observed effects.
The isotopic dipole moment of HDO
Energy Technology Data Exchange (ETDEWEB)
Assafrao, Denise; Mohallem, Jose R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, CP 702, 30123-970, Belo Horizonte, MG (Brazil)
2007-03-14
An adiabatic variational approximation is used to study the monodeuterated water molecule, HDO, accounting for the isotopic effect. The isotopic dipole moment, pointing from D to H, is then calculated for the first time, yielding (1.5 {+-} 0.1) x 10{sup -3} Debye, being helpful in the interpretation of experiments. (fast track communication)
"To Value Every Child in the Moment"
Armstrong, Michael
2014-01-01
This article takes as its starting point the assertion that the purpose of primary education is to value every child in the moment. The author examines one particular story by a six-year-old girl as an example of what this assertion implies, and of its significance for teaching and learning within the primary school.
The Doubling Moment: Resurrecting Edgar Allan Poe
Minnick, J. Bradley; Mergil, Fernando
2008-01-01
This article expands upon Jeffrey Wilhelm's and Brian Edmiston's (1998) concept of a doubling of viewpoints by encouraging middle level students to use dramatization to take on multiple perspectives, to pose interpretive questions, and to enhance critical inquiry from inside and outside of texts. The doubling moment is both the activation of…
Tomás, Sergio; Oliveras, Santi; Cardellach, Estel; Rius, Antonio
2013-04-01
based on the asymmetry between the vertical and horizontal axis of the rain droplets, especially when intense rates of precipitation occur. As a first approximation, the RO signals propagate across the precipitation-volume tangentially, that is, along the local horizontal axis of the droplets. Forward scattering models have been implemented to quantify the sensitivity of L-band signals to different rain rates and precipitation extension being crossed by the signals. The observable considered so far is the polarimetric phase shift: difference between the phase delay suffered by the H- and V-polarizations. Real RO events have been collocated with TRMM precipitation data. The path traveled by the RO signal under a given altitude has been projected on the TRMM grid of observations, to obtain a profile of the precipitation being crossed by the RO link at a given moment of the occultation event. This mechanism has been used to feed the propagation models and thus estimate the polarimetric phase shift that each precipitation event would have induced into the occultation observation. This simulation exercise permits to determine the detectability thresholds and the expected statistics of such collocated events. Methodology and results will be presented.
Hourly Precipitation Data (HPD) Publication
National Oceanic and Atmospheric Administration, Department of Commerce — Hourly Precipitation Data (HPD) Publication is archived and available from the National Climatic Data Center (NCDC). This publication contains hourly precipitation...
Mikheev, N. I.; Goltsman, A. E.; Salekhova, I. G.; Saushin, I. I.
2017-11-01
The results of an experimental evaluation of the third-order moments profiles of velocity fluctuations and their partial derivatives in a zero pressure-gradient turbulent boundary layer are presented. Profiles of characteristics are estimated on the basis of the dynamics of two-component instantaneous velocity vector fields measured by the optical method Smoke Image Velocimetry (SIV). Comparison SIV-measurements with the results of measurements by a thermoanemometer and DNS data with similar Reθ and Reτ showed good agreement between the profiles of +, +, ∂+/∂y+ и ∂+/∂y+ obtained by SIV and DNS.
Precipitation Indices Low Countries
van Engelen, A. F. V.; Ynsen, F.; Buisman, J.; van der Schrier, G.
2009-09-01
Since 1995, KNMI published a series of books(1), presenting an annual reconstruction of weather and climate in the Low Countries, covering the period AD 763-present, or roughly, the last millennium. The reconstructions are based on the interpretation of documentary sources predominantly and comparison with other proxies and instrumental observations. The series also comprises a number of classifications. Amongst them annual classifications for winter and summer temperature and for winter and summer dryness-wetness. The classification of temperature have been reworked into peer reviewed (2) series (AD 1000-present) of seasonal temperatures and temperature indices, the so called LCT (Low Countries Temperature) series, now incorporated in the Millennium databases. Recently we started a study to convert the dryness-wetness classifications into a series of precipitation; the so called LCP (Low Countries Precipitation) series. A brief outline is given here of the applied methodology and preliminary results. The WMO definition for meteorological drought has been followed being that a period is called wet respectively dry when the amount of precipitation is considerable more respectively less than usual (normal). To gain a more quantitative insight for four locations, geographically spread over the Low Countries area (De Bilt, Vlissingen, Maastricht and Uccle), we analysed the statistics of daily precipitation series, covering the period 1900-present. This brought us to the following definition, valid for the Low Countries: A period is considered as (very) dry respectively (very) wet if over a continuous period of at least 60 days (~two months) cq 90 days (~three months) on at least two out of the four locations 50% less resp. 50% more than the normal amount for the location (based on the 1961-1990 normal period) has been measured. This results into the following classification into five drought classes hat could be applied to non instrumental observations: Very wet period
High-Precision Resonant Cavity Beam Position, Emittance and Third-Moment Monitors
Barov, Nikolai; Miller, Roger H; Nantista, Christopher D; Weidemann, A W
2005-01-01
Linear colliders and FEL facilities need fast, nondestructive beam position and profile monitors to facilitate machine tune-up, and for use with feedback control. FAR-TECH, Inc. is developing a resonant cavity diagnostic to simultaneously measure the dipole, quadrupole and sextupole moments of the beam distribution. Measurements of dipole and quadrupole moments at multiple locations yield information about beam orbit and emittance. The sextupole moment can reveal information about beam asymmetry which is useful in diagnosing beam tail deflections caused by short range dipole wakefields. In addition to the resonance enhancement of a single-cell cavity, use of a multi-cell standign-wave structure further enhances signal strength and improves the resolution of the device. An estimated rms beam size resolution is sub micro-meters and beam position is sub nano-meter.
Matrix elements from moments of correlation functions
Energy Technology Data Exchange (ETDEWEB)
Chang, Chia Cheng [SLAC National Accelerator Lab., Menlo Park, CA (United States); Bouchard, Chris [College of William and Mary, Williamsburg, VA (United States); Orginos, Konstantinos [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); College of William and Mary, Williamsburg, VA (United States); Richards, David G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2016-10-01
Momentum-space derivatives of matrix elements can be related to their coordinate-space moments through the Fourier transform. We derive these expressions as a function of momentum transfer Q2 for asymptotic in/out states consisting of a single hadron. We calculate corrections to the finite volume moments by studying the spatial dependence of the lattice correlation functions. This method permits the computation of not only the values of matrix elements at momenta accessible on the lattice, but also the momentum-space derivatives, providing {\\it a priori} information about the Q2 dependence of form factors. As a specific application we use the method, at a single lattice spacing and with unphysically heavy quarks, to directly obtain the slope of the isovector form factor at various Q2, whence the isovector charge radius. The method has potential application in the calculation of any hadronic matrix element with momentum transfer, including those relevant to hadronic weak decays.
Sequence Classification Using Third-Order Moments
DEFF Research Database (Denmark)
Troelsgaard, Rasmus; Hansen, Lars Kai
2017-01-01
. The proposed method provides lower computational complexity at classification time than the usual likelihood-based methods. In order to demonstrate the properties of the proposed method, we perform classification of both simulated data and empirical data from a human activity recognition study.......Model-based classification of sequence data using a set of hidden Markov models is a well-known technique. The involved score function, which is often based on the class-conditional likelihood, can, however, be computationally demanding, especially for long data sequences. Inspired by recent...... theoretical advances in spectral learning of hidden Markov models, we propose a score function based on third-order moments. In particular, we propose to use the Kullback-Leibler divergence between theoretical and empirical third-order moments for classification of sequence data with discrete observations...
Higher Mellin moments for charged current DIS
Energy Technology Data Exchange (ETDEWEB)
Rogal, M.; Moch, S.
2007-06-15
We report on our recent results for deep-inelastic neutrino({nu})-proton(P) scattering. We have computed the perturbative QCD corrections to three loops for the charged current structure functions F{sub 2}, F{sub L} and F{sub 3} for the combination {nu}P- anti {nu}P. In leading twist approximation we have calculated the first six odd-integer Mellin moments in the case of F{sub 2} and F{sub L} and the first six even-integer moments in the case of F{sub 3}. As a new result we have obtained the coefficient functions to O({alpha}{sup 3}{sub s}) and we have found the corresponding anomalous dimensions to agree with known results in the literature. (orig.)
Stochastic development regression using method of moments
DEFF Research Database (Denmark)
Kühnel, Line; Sommer, Stefan Horst
2017-01-01
This paper considers the estimation problem arising when inferring parameters in the stochastic development regression model for manifold valued non-linear data. Stochastic development regression captures the relation between manifold-valued response and Euclidean covariate variables using...... the stochastic development construction. It is thereby able to incorporate several covariate variables and random effects. The model is intrinsically defined using the connection of the manifold, and the use of stochastic development avoids linearizing the geometry. We propose to infer parameters using...... the Method of Moments procedure that matches known constraints on moments of the observations conditional on the latent variables. The performance of the model is investigated in a simulation example using data on finite dimensional landmark manifolds....
The Koszul complex of a moment map
DEFF Research Database (Denmark)
Herbig, Hans-Christian; Schwarz, Gerald W.
2013-01-01
Let $K\\to\\U(V)$ be a unitary representation of the compact Lie group $K$. Then there is a canonical moment mapping $\\rho\\colon V\\to\\liek^*$. We have the Koszul complex ${\\mathcal K}(\\rho,\\mathcal C^\\infty(V))$ of the component functions $\\rho_1,\\dots,\\rho_k$ of $\\rho$. Let $G=K_\\C$, the complexif......Let $K\\to\\U(V)$ be a unitary representation of the compact Lie group $K$. Then there is a canonical moment mapping $\\rho\\colon V\\to\\liek^*$. We have the Koszul complex ${\\mathcal K}(\\rho,\\mathcal C^\\infty(V))$ of the component functions $\\rho_1,\\dots,\\rho_k$ of $\\rho$. Let $G...
DISSOLUTION OF LANTHANUM FLUORIDE PRECIPITATES
Fries, B.A.
1959-11-10
A plutonium separatory ore concentration procedure involving the use of a fluoride type of carrier is presented. An improvement is given in the derivation step in the process for plutonium recovery by carrier precipitation of plutonium values from solution with a lanthanum fluoride carrier precipitate and subsequent derivation from the resulting plutonium bearing carrier precipitate of an aqueous acidic plutonium-containing solution. The carrier precipitate is contacted with a concentrated aqueous solution of potassium carbonate to effect dissolution therein of at least a part of the precipitate, including the plutonium values. Any remaining precipitate is separated from the resulting solution and dissolves in an aqueous solution containing at least 20% by weight of potassium carbonate. The reacting solutions are combined, and an alkali metal hydroxide added to a concentration of at least 2N to precipitate lanthanum hydroxide concomitantly carrying plutonium values.
Clinical significance of precipitous labor.
Suzuki, Shunji
2015-03-01
Precipitous labor is defined as expulsion of the fetus within less than 3 hours of commencement of regular contractions. We retrospectively examined our cases of precipitous labor to identify the clinical significance and perinatal outcomes following precipitous labor in singleton vertex deliveries. A retrospective population-based study was conducted comparing women with singleton precipitous labor and those with labor of normal duration. We examined the clinical characteristics and outcomes by comparing patients with precipitous labor and those with labor of normal duration in 0 and two-parous singleton pregnant women. Using a multivariate analysis, precipitous labor in nulliparous women was independently associated with teenagers (adjusted OR: 1.71, 95% CI: 0.99 - 2.95, P = 0.049), preterm delivery (adjusted OR: 1.77, 95% CI: 1.16 - 2.70, P precipitous labor was associated with hypertensive disorders in singleton vertex deliveries, it was not associated with maternal or neonatal outcomes.
New discrete orthogonal moments for signal analysis
Czech Academy of Sciences Publication Activity Database
Honarvar Shakibaei Asli, Barmak; Flusser, Jan
2017-01-01
Roč. 141, č. 1 (2017), s. 57-73 ISSN 0165-1684 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Orthogonal polynomials * Moment functions * Z-transform * Rodrigues formula * Hypergeometric form Subject RIV: JD - Computer Applications, Robotics Impact factor: 3.110, year: 2016 http:// library .utia.cas.cz/separaty/2017/ZOI/flusser-0475248.pdf
Moments, positive polynomials and their applications
Lasserre, Jean Bernard
2009-01-01
Many important applications in global optimization, algebra, probability and statistics, applied mathematics, control theory, financial mathematics, inverse problems, etc. can be modeled as a particular instance of the Generalized Moment Problem (GMP) . This book introduces a new general methodology to solve the GMP when its data are polynomials and basic semi-algebraic sets. This methodology combines semidefinite programming with recent results from real algebraic geometry to provide a hierarchy of semidefinite relaxations converging to the desired optimal value. Applied on appropriate cones,
Some special moments from last month
Claudia Marcelloni de Oliveira
Integration of the three shells into the ATLAS pixel barrel last month. Lowering of the first sector of the MDT Muon Big Wheel on side C in the ATLAS cavern in December 2006. Some intense moment during the first ATLAS integration run from the main ATLAS control room. Muriel was one of the 20000 ATLAS cavern visitors in 2006 to enjoy herself during her visit.
Analytic Moment-based Gaussian Process Filtering
Deisenroth, MP; Huber, MF; Hanebeck, UD
2009-01-01
04.07.13 KB. Ok to add accepted version to Spiral, authors retain copyright. We propose an analytic moment-based filter for nonlinear stochastic dynamic systems modeled by Gaussian processes. Exact expressions for the expected value and the covariance matrix are provided for both the prediction step and the filter step, where an additional Gaussian assumption is exploited in the latter case. Our filter does not require further approximations. In particular, it avoids finite-sample approxi...
A big measurement of a small moment
E Sauer, B.; Devlin, J. A.; Rabey, I. M.
2017-07-01
A beam of ThO molecules has been used to make the most precise measurement of the electron’s electric dipole moment (EDM) to date. In their recent paper, the ACME collaboration set out in detail their experimental and data analysis techniques. In a tour-de-force, they explain the many ways in which their apparatus can produce a signal which mimics the EDM and show how these systematic effects are measured and controlled.
Kairos time at the moment of birth.
Crowther, Susan; Smythe, Elizabeth; Spence, Deb
2015-04-01
there is something extraordinary in the lived experience of being there at the time of birth. Yet the meaning and significance of this special time, named Kairos time in this paper, have received little attention. to describe the lived-experience of Kairos time at birth and surface its meaning. this is an interpretive hermeneutic phenomenology study informed by the writings of Heidegger and Gadamer. 14 in-depth interviews with mothers, birth partners, midwives and obstetricians were transcribed and stories from the data were hermeneutically analysed. there is a time, like no other, at the moment of birth that is widely known and valued. This paper reveals and names this phenomenon Kairos time. This is a felt-time that is lineal, process and cyclic time and more. Kairos time describes an existential temporal experience that is rich in significant sacred meaning; a time of emergent insight rarely spoken about in practice yet touches everyone present. The notion of Kairos time in relation to the moment of birth is introduced as a reminder of something significant that matters. Kairos time is revealed as a moment in and beyond time. It has a temporal enigmatic mystery involving spiritual connectedness. Kairos time is a time of knowing and remembrance of our shared natality. In this time life is disclosed as extraordinary and beyond everyday personal and professional concerns. It is all this and more. Kairos time at birth is precious and powerful yet vulnerable. It needs to be safeguarded to ensure its presence continues to emerge. This means maternity care providers and others at birth need to shelter and protect Kairos time from the sometimes harsh realities of birth and the potentially insensitive ways of being there at the moments of birth. Those who find themselves at birth need to pause and allow the profundity of its meaning to surface and inspire their actions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Monte Carlo Volcano Seismic Moment Tensors
Waite, G. P.; Brill, K. A.; Lanza, F.
2015-12-01
Inverse modeling of volcano seismic sources can provide insight into the geometry and dynamics of volcanic conduits. But given the logistical challenges of working on an active volcano, seismic networks are typically deficient in spatial and temporal coverage; this potentially leads to large errors in source models. In addition, uncertainties in the centroid location and moment-tensor components, including volumetric components, are difficult to constrain from the linear inversion results, which leads to a poor understanding of the model space. In this study, we employ a nonlinear inversion using a Monte Carlo scheme with the objective of defining robustly resolved elements of model space. The model space is randomized by centroid location and moment tensor eigenvectors. Point sources densely sample the summit area and moment tensors are constrained to a randomly chosen geometry within the inversion; Green's functions for the random moment tensors are all calculated from modeled single forces, making the nonlinear inversion computationally reasonable. We apply this method to very-long-period (VLP) seismic events that accompany minor eruptions at Fuego volcano, Guatemala. The library of single force Green's functions is computed with a 3D finite-difference modeling algorithm through a homogeneous velocity-density model that includes topography, for a 3D grid of nodes, spaced 40 m apart, within the summit region. The homogenous velocity and density model is justified by long wavelength of VLP data. The nonlinear inversion reveals well resolved model features and informs the interpretation through a better understanding of the possible models. This approach can also be used to evaluate possible station geometries in order to optimize networks prior to deployment.
Facades structure detection by geometric moment
Jiang, Diqiong; Chen, Hui; Song, Rui; Meng, Lei
2017-06-01
This paper proposes a novel method for extracting facades structure from real-world pictures by using local geometric moment. Compared with existing methods, the proposed method has advantages of easy-to-implement, low computational cost, and robustness to noises, such as uneven illumination, shadow, and shade from other objects. Besides, our method is faster and has a lower space complexity, making it feasible for mobile devices and the situation where real-time data processing is required. Specifically, a facades structure modal is first proposed to support the use of our special noise reduction method, which is based on a self-adapt local threshold with Gaussian weighted average for image binarization processing and the feature of the facades structure. Next, we divide the picture of the building into many individual areas, each of which represents a door or a window in the picture. Subsequently we calculate the geometric moment and centroid for each individual area, for identifying those collinear ones based on the feature vectors, each of which is thereafter replaced with a line. Finally, we comprehensively analyze all the geometric moment and centroid to find out the facades structure of the building. We compare our result with other methods and especially report the result from the pictures taken in bad environmental conditions. Our system is designed for two application, i.e, the reconstruction of facades based on higher resolution ground-based on imagery, and the positional system based on recognize the urban building.
Energy Technology Data Exchange (ETDEWEB)
Correll, F.D.; Madansky, L.; Hardekopf, R.A.; Sunier, J.W.
1983-08-01
The ground-state magnetic dipole and electric quadrupole moments of the ..beta.. emitter /sup 9/Li (J/sup ..pi../ = (3/2)/sup -/, T/sub 1/2/ = 0.176 s) have been measured for the first time. Polarized /sup 9/Li nuclei were produced in the /sup 7/Li(t,p) reaction, using 5--6 MeV polarized tritons. The recoiling /sup 9/Li nuclei were stopped either in Au foils or in LiNbO/sub 3/ single crystals, and their polarization was detected by measuring the ..beta..-decay asymmetry. Nuclear magnetic resonance techniques were used to depolarize the nuclei, and the resonant frequencies were deduced from changes in the asymmetry. The /sup 9/Li dipole moment was deduced from the measured Larmor frequency in Au; the result, including corrections for diamagnetic shielding and the Knight shift, is Vertical Bar..mu..Vertical Bar = 3.4391(6) ..mu../sub N/. The ratio of the /sup 9/Li quadrupole moment to that of /sup 7/Li was derived from their respective quadrupole couplings in LiNbO/sub 3/; the value is Vertical BarQ( /sup 9/Li)/Q( /sup 7/Li)Vertical Bar = 0. 88 +- 0.18. Both results are in agreement with shell model predictions.
On moments-based Heisenberg inequalities
Zozor, Steeve; Portesi, Mariela; Sanchez-Moreno, Pablo; Dehesa, Jesus S.
2011-03-01
In this paper we revisit the quantitative formulation of the Heisenberg uncertainty principle. The primary version of this principle establishes the impossibility of refined simultaneous measurement of position x and momentum u for a (1-dimensional) quantum particle in terms of variances: ⩾1/4. Since this inequality applies provided each variance exists, some authors proposed entropic versions of this principle as an alternative (employing Shannon's or Rényi's entropies). As another alternative, we consider moments-based formulations and show that inequalities involving moments of orders other than 2 can be found. Our procedure is based on the Rényi entropic versions of the Heisenberg relation together with the search for the maximal entropy under statistical moments' constraints ( and ). Our result improves a relation proposed very recently by Dehesa et al.. [1] where the same approach was used but starting with the Shannon version of the entropic uncertainty relation. Furthermore, we show that when a =b, the best bound we can find with our approach coincides with that of Ref. [1] and, in addition, for a = b = 2 the variance-based Heisenberg relation is recovered. Finally, we illustrate our results in the cases of d-dimensional hydrogenic systems.
Improved moment scaling estimation for multifractal signals
Directory of Open Access Journals (Sweden)
D. Veneziano
2009-11-01
Full Text Available A fundamental problem in the analysis of multifractal processes is to estimate the scaling exponent K(q of moments of different order q from data. Conventional estimators use the empirical moments μ^_{r}^{q}=⟨ | ε_{r}(τ|^{q}⟩ of wavelet coefficients ε_{r}(τ, where τ is location and r is resolution. For stationary measures one usually considers "wavelets of order 0" (averages, whereas for functions with multifractal increments one must use wavelets of order at least 1. One obtains K^(q as the slope of log( μ^_{r}^{q} against log(r over a range of r. Negative moments are sensitive to measurement noise and quantization. For them, one typically uses only the local maxima of | ε_{r}(τ| (modulus maxima methods. For the positive moments, we modify the standard estimator K^(q to significantly reduce its variance at the expense of a modest increase in the bias. This is done by separately estimating K(q from sub-records and averaging the results. For the negative moments, we show that the standard modulus maxima estimator is biased and, in the case of additive noise or quantization, is not applicable with wavelets of order 1 or higher. For these cases we propose alternative estimators. We also consider the fitting of parametric models of K(q and show how, by splitting the record into sub-records as indicated above, the accuracy of standard methods can be significantly improved.
Regional Frequency and Uncertainty Analysis of Extreme Precipitation in Bangladesh
Mortuza, M. R.; Demissie, Y.; Li, H. Y.
2014-12-01
Increased frequency of extreme precipitations, especially those with multiday durations, are responsible for recent urban floods and associated significant losses of lives and infrastructures in Bangladesh. Reliable and routinely updated estimation of the frequency of occurrence of such extreme precipitation events are thus important for developing up-to-date hydraulic structures and stormwater drainage system that can effectively minimize future risk from similar events. In this study, we have updated the intensity-duration-frequency (IDF) curves for Bangladesh using daily precipitation data from 1961 to 2010 and quantified associated uncertainties. Regional frequency analysis based on L-moments is applied on 1-day, 2-day and 5-day annual maximum precipitation series due to its advantages over at-site estimation. The regional frequency approach pools the information from climatologically similar sites to make reliable estimates of quantiles given that the pooling group is homogeneous and of reasonable size. We have used Region of influence (ROI) approach along with homogeneity measure based on L-moments to identify the homogenous pooling groups for each site. Five 3-parameter distributions (i.e., Generalized Logistic, Generalized Extreme value, Generalized Normal, Pearson Type Three, and Generalized Pareto) are used for a thorough selection of appropriate models that fit the sample data. Uncertainties related to the selection of the distributions and historical data are quantified using the Bayesian Model Averaging and Balanced Bootstrap approaches respectively. The results from this study can be used to update the current design and management of hydraulic structures as well as in exploring spatio-temporal variations of extreme precipitation and associated risk.
The Global Precipitation Climatology Project (GPCP) Combined Precipitation Dataset
Huffman, George J.; Adler, Robert F.; Arkin, Philip; Chang, Alfred; Ferraro, Ralph; Gruber, Arnold; Janowiak, John; McNab, Alan; Rudolf, Bruno; Schneider, Udo
1997-01-01
The Global Precipitation Climatology Project (GPCP) has released the GPCP Version 1 Combined Precipitation Data Set, a global, monthly precipitation dataset covering the period July 1987 through December 1995. The primary product in the dataset is a merged analysis incorporating precipitation estimates from low-orbit-satellite microwave data, geosynchronous-orbit -satellite infrared data, and rain gauge observations. The dataset also contains the individual input fields, a combination of the microwave and infrared satellite estimates, and error estimates for each field. The data are provided on 2.5 deg x 2.5 deg latitude-longitude global grids. Preliminary analyses show general agreement with prior studies of global precipitation and extends prior studies of El Nino-Southern Oscillation precipitation patterns. At the regional scale there are systematic differences with standard climatologies.
The Super Tuesday Outbreak: Forecast Sensitivities to Single-Moment Microphysics Schemes
Molthan, Andrew L.; Case, Jonathan L.; Dembek, Scott R.; Jedlovec, Gary J.; Lapenta, William M.
2008-01-01
Forecast precipitation and radar characteristics are used by operational centers to guide the issuance of advisory products. As operational numerical weather prediction is performed at increasingly finer spatial resolution, convective precipitation traditionally represented by sub-grid scale parameterization schemes is now being determined explicitly through single- or multi-moment bulk water microphysics routines. Gains in forecasting skill are expected through improved simulation of clouds and their microphysical processes. High resolution model grids and advanced parameterizations are now available through steady increases in computer resources. As with any parameterization, their reliability must be measured through performance metrics, with errors noted and targeted for improvement. Furthermore, the use of these schemes within an operational framework requires an understanding of limitations and an estimate of biases so that forecasters and model development teams can be aware of potential errors. The National Severe Storms Laboratory (NSSL) Spring Experiments have produced daily, high resolution forecasts used to evaluate forecast skill among an ensemble with varied physical parameterizations and data assimilation techniques. In this research, high resolution forecasts of the 5-6 February 2008 Super Tuesday Outbreak are replicated using the NSSL configuration in order to evaluate two components of simulated convection on a large domain: sensitivities of quantitative precipitation forecasts to assumptions within a single-moment bulk water microphysics scheme, and to determine if these schemes accurately depict the reflectivity characteristics of well-simulated, organized, cold frontal convection. As radar returns are sensitive to the amount of hydrometeor mass and the distribution of mass among variably sized targets, radar comparisons may guide potential improvements to a single-moment scheme. In addition, object-based verification metrics are evaluated for
ISLSCP II Global Precipitation Climatology Centre (GPCC) Monthly Precipitation
National Aeronautics and Space Administration — ABSTRACT: The Global Precipitation Climatology Centre (GPCC), which is operated by the Deutscher Wetterdienst (National Meteorological Service of Germany), is a...
ISLSCP II Global Precipitation Climatology Centre (GPCC) Monthly Precipitation
National Aeronautics and Space Administration — The Global Precipitation Climatology Centre (GPCC), which is operated by the Deutscher Wetterdienst (National Meteorological Service of Germany), is a component of...
Hartigan, Erin; Aucoin, Jennifer; Carlson, Rita; Klieber-Kusak, Melanie; Murray, Thomas; Shaw, Bernadette; Lawrence, Michael
Weighted gait increases internal knee extension moment impulses (KEMI) in the anterior cruciate ligament-reconstructed (ACLR) limb; however, limb differences persist. (1) KEMI during normal gait will influence KEMI during weighted gait and (2) peak knee extension (PKE) torque and time to reach PKE torque will predict KEMI during gait tasks. Descriptive laboratory study. Twenty-four women and 14 men completed 3 gait tasks (unweighted, vest, sled) and strength testing after discharge from rehabilitation and clearance to return to sports. KEMI were calculated during the first 25% of stance. PKE torque and time to reach PKE torque were obtained using a dynamometer. Data on the ACLR limb and symmetry indices (SIs) were analyzed for each sex. Women presented with asymmetrical PKE torques and KEMI across tasks. There were three correlations noted for KEMI: between the walk and vest, walk and sled, and vest and sled tasks. Slower time to PKE torque predicted limb asymmetries across tasks and KEMI in the ACLR limb during the sled task. Men presented with asymmetrical PKE torques and KEMI during the sled task. There was a correlation noted for KEMI between walk and vest tasks only. During the sled task, ACLR limb time to PKE torque predicted KEMI in the ACLR limb and PKE torque SI predicted KEMI SI. Women use asymmetrical KEMI profiles during all gait tasks, and those with worse KEMI during walking have worse KEMI during weighted gait. Men have asymmetrical KEMI when sled towing, and these KEMIs do not correlate with KEMI during walking or vest tasks. PKE torque deficits persist when attempting to return to sports. Only men use gains in PKE torque to improve KEMI profiles. Although quicker PKE torque generation will increase KEMI in women, normalization of KEMI profiles will not occur by increasing rate of force development only. Gait retraining is recommended to correct asymmetrical KEMI profiles used across gait tasks in women.
Precipitation-Based ENSO Indices
Adler, Robert; Curtis, Scott
1998-01-01
In this study gridded observed precipitation data sets are used to construct rainfall-based ENSO indices. The monthly El Nino and La Nina Indices (EI and LI) measure the steepest zonal gradient of precipitation anomalies between the equatorial Pacific and the Maritime Continent. This is accomplished by spatially averaging precipitation anomalies using a spatial boxcar filter, finding the maximum and minimum averages within a Pacific and Maritime Continent domain for each month, and taking differences. EI and LI can be examined separately or combined to produce one ENSO Precipitation Index (ESPI). ESPI is well correlated with traditional sea surface temperature and pressure indices, leading Nino 3.4. One advantage precipitation indices have over more conventional indices, is describing the strength and position of the Walker circulation. Examples are given of tracking the impact of ENSO events on the tropical precipitation fields.
Second Moment Method on k-SAT: a General Framework
Hugel, Thomas
2010-01-01
We give a general framework implementing the Second Moment Method on k-SAT and discuss the conditions making the Second Moment Method work in this framework. As applications, we make the Second Moment Method work on boolean solutions and implicants. We extend this to the distributional model of k-SAT.
Recent measurements of nuclear moments far from stability
Keim, M
1998-01-01
Measurements of nuclear moments far from stability have been performed mainly applying laser spectroscopy and $\\beta$-NMR spectroscopy. A short overview of the experimental techniques are given. The $\\beta$-NMR experiments on the quadrupole moments of sodium isotopes and of the magnetic moment of $^{11}$Be, both using optically pumped radioactive beams, are discussed in more detail. (23 refs).
Electrical operation of electrostatic precipitators
Parker, Ken
2003-01-01
The electrostatic precipitator remains on of the most cost effective means of controlling the emission of particulates from most industrial processes. This book will be of interest to both users and suppliers of electrostatic precipitators as well as advanced students on environmental based courses. The author identifies the physical and engineering basis for the development of electrical equipment for electrostatic precipitators and thoroughly explores the technological factors which optimize the efficiency of the precipitator and hence minimize emissions, as well as future developments in th
Precipitation Measurement Missions Data Access
National Aeronautics and Space Administration — Tropical Rainfall Measuring Mission (TRMM) data products are currently available from 1998 to the present. Global Precipitation Measurement (GPM) mission data...
Measuring precipitation with a geolysimeter
Smith, Craig D.; van der Kamp, Garth; Arnold, Lauren; Schmidt, Randy
2017-10-01
Using the relationship between measured groundwater pressures in deep observation wells and total surface loading, a geological weighing lysimeter (geolysimeter) has the capability of measuring precipitation event totals independently of conventional precipitation gauge observations. Correlations between groundwater pressure change and event precipitation were observed at a co-located site near Duck Lake, SK, over a multi-year and multi-season period. Correlation coefficients (r2) varied from 0.99 for rainfall to 0.94 for snowfall. The geolysimeter was shown to underestimate rainfall by 7 % while overestimating snowfall by 9 % as compared to the unadjusted gauge precipitation. It is speculated that the underestimation of rainfall is due to unmeasured run-off and evapotranspiration within the response area of the geolysimeter during larger rainfall events, while the overestimation of snow is at least partially due to the systematic undercatch common to most precipitation gauges due to wind. Using recently developed transfer functions from the World Meteorological Organization's (WMO) Solid Precipitation Intercomparison Experiment (SPICE), bias adjustments were applied to the Alter-shielded, Geonor T-200B precipitation gauge measurements of snowfall to mitigate wind-induced errors. The bias between the gauge and geolysimeter measurements was reduced to 3 %. This suggests that the geolysimeter is capable of accurately measuring solid precipitation and can be used as an independent and representative reference of true precipitation.
Measuring precipitation with a geolysimeter
Directory of Open Access Journals (Sweden)
C. D. Smith
2017-10-01
Full Text Available Using the relationship between measured groundwater pressures in deep observation wells and total surface loading, a geological weighing lysimeter (geolysimeter has the capability of measuring precipitation event totals independently of conventional precipitation gauge observations. Correlations between groundwater pressure change and event precipitation were observed at a co-located site near Duck Lake, SK, over a multi-year and multi-season period. Correlation coefficients (r2 varied from 0.99 for rainfall to 0.94 for snowfall. The geolysimeter was shown to underestimate rainfall by 7 % while overestimating snowfall by 9 % as compared to the unadjusted gauge precipitation. It is speculated that the underestimation of rainfall is due to unmeasured run-off and evapotranspiration within the response area of the geolysimeter during larger rainfall events, while the overestimation of snow is at least partially due to the systematic undercatch common to most precipitation gauges due to wind. Using recently developed transfer functions from the World Meteorological Organization's (WMO Solid Precipitation Intercomparison Experiment (SPICE, bias adjustments were applied to the Alter-shielded, Geonor T-200B precipitation gauge measurements of snowfall to mitigate wind-induced errors. The bias between the gauge and geolysimeter measurements was reduced to 3 %. This suggests that the geolysimeter is capable of accurately measuring solid precipitation and can be used as an independent and representative reference of true precipitation.
The Magnetic Moment of the Lambda Hyperon
Energy Technology Data Exchange (ETDEWEB)
Schachinger, Lindsay Carol [Rutgers Univ., Piscataway, NJ (United States)
1978-10-01
The magnetic moment of the lambda hyperon has been measured to be· -0.613S±0.0047 nuclear magneton. The experiment was performed in the neutral hyperon beam at the Fermi National Accelerator Laboratory. Three million $\\Lambda^0 \\to p \\pi^-$ decays were detected in a multi-wire proportional chamber spectrometer. The lambda sample, produced inclusively by 400 Gev protons, had an. average momentum of 114 Gev / c and an average polarization of 0.085. This polarization was precessed through angles as large as 153 degrees
Right-handed neutrino magnetic moments
Energy Technology Data Exchange (ETDEWEB)
Aparici, Alberto; Kim, Kyungwook; Santamaria, Arcadi; Wudka, Jose, E-mail: alberto.aparici@uv.es
2010-11-01
We consider the most general dimension 5 effective Lagrangian that can be built using only Standard Model fields plus right-handed neutrinos, and fnd that there exists a term that provides electroweak moments (i.e., couplings to the Z and photon) for the right-handed neutrinos. Such term has not been described previously in the literature. We discuss its phenomenology and the bounds that can be derived from LEP results and from the observation of the cooling process of red giants and supernovae.
Right-handed neutrino magnetic moments
Aparici, Alberto; Kim, Kyungwook; Santamaria, Arcadi; Wudka, José
2010-11-01
We consider the most general dimension 5 efective Lagrangian that can be built using only Standard Model felds plus right-handed neutrinos, and fnd that there exists a term that provides electroweak moments (i.e., couplings to the Z and photon) for the right-handed neutrinos. Such term has not been described previously in the literature. We discuss its phenomenology and the bounds that can be derived from LEP results and from the observation of the cooling process of red giants and supernovae.
EDM: Neutron electric dipole moment measurement
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Peter Fierlinger
2016-02-01
Full Text Available An electric dipole moment (EDM of the neutron would be a clear sign of new physics beyond the standard model of particle physics. The search for this phenomenon is considered one of the most important experiments in fundamental physics and could provide key information on the excess of matter versus antimatter in the universe. With high measurement precision, this experiment aims to ultimately achieve a sensitivity of 10-28 ecm, a 100-fold improvement in the sensitivity compared to the state-of-the-art. The EDM instrument is operated by an international collaboration based at the Technische Universität München.
Further analysis of the connected moments expansion
Energy Technology Data Exchange (ETDEWEB)
Amore, Paolo; Rodriguez, Martin [Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima, Colima (Mexico); Fernandez, Francisco M, E-mail: paolo.amore@gmail.com, E-mail: fernande@quimica.unlp.edu.ar, E-mail: martinalexander.rv@gmail.com [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Blvd. 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)
2011-12-16
By means of simple quantum-mechanical models we show that under certain conditions the main assumptions of the connected moments expansion (CMX) are no longer valid. In particular, we consider two-level systems: the harmonic oscillator and the pure quartic oscillator. Although derived from such simple models, we think that the results of this investigation may be of utility in future applications of the approach to realistic problems. We show that a straightforward analysis of the CMX exponential parameters may provide a clear indication of the success of the approach. (paper)
Rising Precipitation Extremes across Nepal
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Ramchandra Karki
2017-01-01
Full Text Available As a mountainous country, Nepal is most susceptible to precipitation extremes and related hazards, including severe floods, landslides and droughts that cause huge losses of life and property, impact the Himalayan environment, and hinder the socioeconomic development of the country. Given that the countrywide assessment of such extremes is still lacking, we present a comprehensive picture of prevailing precipitation extremes observed across Nepal. First, we present the spatial distribution of daily extreme precipitation indices as defined by the Expert Team on Climate Change Detection, Monitoring and Indices (ETCCDMI from 210 stations over the period of 1981–2010. Then, we analyze the temporal changes in the computed extremes from 76 stations, featuring long-term continuous records for the period of 1970–2012, by applying a non-parametric Mann−Kendall test to identify the existence of a trend and Sen’s slope method to calculate the true magnitude of this trend. Further, the local trends in precipitation extremes have been tested for their field significance over the distinct physio-geographical regions of Nepal, such as the lowlands, middle mountains and hills and high mountains in the west (WL, WM and WH, respectively, and likewise, in central (CL, CM and CH and eastern (EL, EM and EH Nepal. Our results suggest that the spatial patterns of high-intensity precipitation extremes are quite different to that of annual or monsoonal precipitation. Lowlands (Terai and Siwaliks that feature relatively low precipitation and less wet days (rainy days are exposed to high-intensity precipitation extremes. Our trend analysis suggests that the pre-monsoonal precipitation is significantly increasing over the lowlands and CH, while monsoonal precipitation is increasing in WM and CH and decreasing in CM, CL and EL. On the other hand, post-monsoonal precipitation is significantly decreasing across all of Nepal while winter precipitation is decreasing
Space Station Control Moment Gyroscope Lessons Learned
Gurrisi, Charles; Seidel, Raymond; Dickerson, Scott; Didziulis, Stephen; Frantz, Peter; Ferguson, Kevin
2010-01-01
Four 4760 Nms (3510 ft-lbf-s) Double Gimbal Control Moment Gyroscopes (DGCMG) with unlimited gimbal freedom about each axis were adopted by the International Space Station (ISS) Program as the non-propulsive solution for continuous attitude control. These CMGs with a life expectancy of approximately 10 years contain a flywheel spinning at 691 rad/s (6600 rpm) and can produce an output torque of 258 Nm (190 ft-lbf)1. One CMG unexpectedly failed after approximately 1.3 years and one developed anomalous behavior after approximately six years. Both units were returned to earth for failure investigation. This paper describes the Space Station Double Gimbal Control Moment Gyroscope design, on-orbit telemetry signatures and a summary of the results of both failure investigations. The lessons learned from these combined sources have lead to improvements in the design that will provide CMGs with greater reliability to assure the success of the Space Station. These lessons learned and design improvements are not only applicable to CMGs but can be applied to spacecraft mechanisms in general.
Shuffle dislocation induced magnetic moment in graphene
Energy Technology Data Exchange (ETDEWEB)
Lopez-Sancho, M.P., E-mail: pilar@icmm.csic.e [Instituto de Ciencia de Materiales de Madrid-CSIC, C/Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain); Juan, F. de; Vozmediano, M.A.H. [Instituto de Ciencia de Materiales de Madrid-CSIC, C/Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain)
2010-05-15
Graphene, a honeycomb arrangement of carbon atoms, is a promising material for nanoelectronics applications due to its unusual electronic properties. Recent experiments performed on suspended graphene indicate the existence of intrinsic defects on the samples. It is known that lattice defects such as vacancies or voids leaving unpaired atoms, lead to the formation of local magnetic moments (Vozmediano et al., 2005). The existence and ordering of these moments is largely determined by the bipartite character of the honeycomb lattice seen as two interpenetrating triangular sublattices. Dislocations made by pentagon-heptagon pairs or octagons with an unpaired atom have been studied recently and found to be stable in the graphene lattice (Carpio et al., 2008). These defects frustrate the sublattice structure and affect the magnetic properties of graphene. We study the magnetic properties of graphene in the presence of these defects. The system is described by a p{sub z} tight-binding model with electron-electron interactions modelled by a Hubbard term. Spin-polarized mean-field solutions are investigated within an unrestricted Hartree-Fock approximation.
Moment equations in spatial evolutionary ecology.
Lion, Sébastien
2016-09-21
How should we model evolution in spatially structured populations? Here, I review an evolutionary ecology approach based on the technique of spatial moment equations. I first provide a mathematical underpinning to the derivation of equations for the densities of various spatial configurations in network-based models. I then show how this spatial ecological framework can be coupled with an adaptive dynamics approach to compute the invasion fitness of a rare mutant in a resident population at equilibrium. Under the additional assumption that mutations have small phenotypic effects, I show that the selection gradient can be expressed as a function of neutral measures of genetic and demographic structure. I discuss the connections between this approach and inclusive fitness theory, as well as the applicability and limits of this technique. My main message is that spatial moment equations can be used as a means to obtain compact qualitative arguments about the evolution of life-history traits for a variety of life cycles. Copyright © 2015 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Isabelle Rogowski
Full Text Available This study examined the effect of the polar moment of inertia of a tennis racket on upper limb loading in the serve. Eight amateur competition tennis players performed two sets of 10 serves using two rackets identical in mass, position of center of mass and moments of inertia other than the polar moment of inertia (0.00152 vs 0.00197 kg.m2. An eight-camera motion analysis system collected the 3D trajectories of 16 markers, located on the thorax, upper limbs and racket, from which shoulder, elbow and wrist net joint moments and powers were computed using inverse dynamics. During the cocking phase, increased racket polar moment of inertia was associated with significant increases in the peak shoulder extension and abduction moments, as well the peak elbow extension, valgus and supination moments. During the forward swing phase, peak wrist extension and radial deviation moments significantly increased with polar moment of inertia. During the follow-through phase, the peak shoulder adduction, elbow pronation and wrist external rotation moments displayed a significant inverse relationship with polar moment of inertia. During the forward swing, the magnitudes of negative joint power at the elbow and wrist were significantly larger when players served using the racket with a higher polar moment of inertia. Although a larger polar of inertia allows players to better tolerate off-center impacts, it also appears to place additional loads on the upper extremity when serving and may therefore increase injury risk in tennis players.
Resistivity Problems in Electrostatic Precipitation
White, Harry J.
1974-01-01
The process of electrostatic precipitation has ever-increasing application in more efficient collection of fine particles from industrial air emissions. This article details a large number of new developments in the field. The emphasis is on high resistivity particles which are a common cause of poor precipitator performance. (LS)
Acid precipitation and forest soils
C. O. Tamm
1976-01-01
Many soil processes and properties may be affected by a change in chemical climate such as that caused by acidification of precipitation. The effect of additions of acid precipitation depends at first on the extent to which this acid is really absorbed by the soil and on the changes in substances with actual or potential acidity leaving the soil. There is for instance...
Precipitation in the Solar System
McIntosh, Gordon
2007-01-01
As an astronomy instructor, I am always looking for commonly observed Earthly experiences to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote a short TPT article on frost. This paper is on the related phenomena of precipitation. Precipitation, so common on most of the Earth's…
Modeling solid-state precipitation
Nebylov, AlexanderKozeschnik, Ernst
2012-01-01
Over recent decades, modeling and simulation of solid-state precipitation has attracted increased attention in academia and industry due to their important contributions in designing properties of advanced structural materials and in increasing productivity and decreasing costs for expensive alloying. In particular, precipitation of second phases is an important means for controlling the mechanical-technological properties of structural materials. However, profound physical modeling of precipitation is not a trivial task. This book introduces you to the classical methods of precipitation modeling and to recently-developed advanced, computationally-efficient techniques. If you're a research professional, academic, or student, you'll learn: nucleation theory, precipitate growth, calculation of interfacial energies. advanced techniques for technologically relevant multicomponent systems and complex thermo-mechanical treatments. numerical approaches using evolution equations and discrete particle size distribu...
Levitt, Heidi; Butler, Mike; Hill, Travis
2006-01-01
Clients who had completed psychotherapy were interviewed about the significant experiences and moments they recalled within their sessions. These interviews were analyzed using grounded theory, creating a hierarchy of categories that represent what clients find important in therapy. From the hermeneutic analysis of the content of these categories,…
Forces and moments generated by the human arm: Variability and control
Xu, Y; Terekhov, AV; Latash, ML; Zatsiorsky, VM
2012-01-01
This is an exploratory study of the accurate endpoint force vector production by the human arm in isometric conditions. We formulated three common-sense hypotheses and falsified them in the experiment. The subjects (n=10) exerted static forces on the handle in eight directions in a horizontal plane for 25 seconds. The forces were of 4 magnitude levels (10 %, 20%, 30% and 40% of individual MVC). The torsion moment on the handle (grasp moment) was not specified in the instruction. The two force components and the grasp moment were recorded, and the shoulder, elbow, and wrist joint torques were computed. The following main facts were observed: (a) While the grasp moment was not prescribed by the instruction, it was always produced. The moment magnitude and direction depended on the instructed force magnitude and direction. (b) The within-trial angular variability of the exerted force vector (angular precision) did not depend on the target force magnitude (a small negative correlation was observed). (c) Across the target force directions, the variability of the exerted force magnitude and directional variability exhibited opposite trends: In the directions where the variability of force magnitude was maximal, the directional variability was minimal and vice versa. (d) The time profiles of joint torques in the trials were always positively correlated, even for the force directions where flexion torque was produced at one joint and extension torque was produced at the other joint. (e) The correlations between the grasp moment and the wrist torque were negative across the tasks and positive within the individual trials. (f) In static serial kinematic chains, the pattern of the joint torques distribution could not be explained by an optimization cost function additive with respect to the torques. Plans for several future experiments have been suggested. PMID:23080084
Use of co-precipitates of Brachystegia Eurycoma gum and egg ...
African Journals Online (AJOL)
precipitates of Brachystegia gum and egg albumin as binder, and testing the stability of the metronidazole tablets with regard to moisture uptake and also the effect of moisture sorption on disintegration and dissolution profiles of the tablets.
VHF signal power suppression in stratiform and convective precipitation
Directory of Open Access Journals (Sweden)
A. J. McDonald
2006-03-01
Full Text Available Previous studies have indicated that VHF clear-air radar return strengths are reduced during periods of precipitation. This study aims to examine whether the type of precipitation, stratiform and convective precipitation types are identified, has any impact on the relationships previously observed and to examine the possible mechanisms which produce this phenomenon. This study uses a combination of UHF and VHF wind-profiler data to define periods associated with stratiform and convective precipitation. This identification is achieved using an algorithm which examines the range squared corrected signal to noise ratio of the UHF returns for a bright band signature for stratiform precipitation. Regions associated with convective rainfall have been defined by identifying regions of enhanced range corrected signal to noise ratio that do not display a bright band structure and that are relatively uniform until a region above the melting layer.
This study uses a total of 68 days, which incorporated significant periods of surface rainfall, between 31 August 2000 and 28 February 2002 inclusive from Aberystwyth (52.4° N, 4.1° W. Examination suggests that both precipitation types produce similar magnitude reductions in VHF signal power on average. However, the frequency of occurrence of statistically significant reductions in VHF signal power are very different. In the altitude range 2-4 km stratiform precipitation is related to VHF signal suppression approximately 50% of the time while in convective precipitation suppression is observed only 27% of the time. This statistical result suggests that evaporation, which occurs more often in stratiform precipitation, is important in reducing the small-scale irregularities in humidity and thereby the radio refractive index. A detailed case study presented also suggests that evaporation reducing small-scale irregularities in humidity may contribute to the observed VHF signal
VHF signal power suppression in stratiform and convective precipitation
Directory of Open Access Journals (Sweden)
A. J. McDonald
2006-03-01
Full Text Available Previous studies have indicated that VHF clear-air radar return strengths are reduced during periods of precipitation. This study aims to examine whether the type of precipitation, stratiform and convective precipitation types are identified, has any impact on the relationships previously observed and to examine the possible mechanisms which produce this phenomenon. This study uses a combination of UHF and VHF wind-profiler data to define periods associated with stratiform and convective precipitation. This identification is achieved using an algorithm which examines the range squared corrected signal to noise ratio of the UHF returns for a bright band signature for stratiform precipitation. Regions associated with convective rainfall have been defined by identifying regions of enhanced range corrected signal to noise ratio that do not display a bright band structure and that are relatively uniform until a region above the melting layer. This study uses a total of 68 days, which incorporated significant periods of surface rainfall, between 31 August 2000 and 28 February 2002 inclusive from Aberystwyth (52.4° N, 4.1° W. Examination suggests that both precipitation types produce similar magnitude reductions in VHF signal power on average. However, the frequency of occurrence of statistically significant reductions in VHF signal power are very different. In the altitude range 2-4 km stratiform precipitation is related to VHF signal suppression approximately 50% of the time while in convective precipitation suppression is observed only 27% of the time. This statistical result suggests that evaporation, which occurs more often in stratiform precipitation, is important in reducing the small-scale irregularities in humidity and thereby the radio refractive index. A detailed case study presented also suggests that evaporation reducing small-scale irregularities in humidity may contribute to the observed VHF signal suppression.
Fast Legendre moment computation for template matching
Li, Bing C.
2017-05-01
Normalized cross correlation (NCC) based template matching is insensitive to intensity changes and it has many applications in image processing, object detection, video tracking and pattern recognition. However, normalized cross correlation implementation is computationally expensive since it involves both correlation computation and normalization implementation. In this paper, we propose Legendre moment approach for fast normalized cross correlation implementation and show that the computational cost of this proposed approach is independent of template mask sizes which is significantly faster than traditional mask size dependent approaches, especially for large mask templates. Legendre polynomials have been widely used in solving Laplace equation in electrodynamics in spherical coordinate systems, and solving Schrodinger equation in quantum mechanics. In this paper, we extend Legendre polynomials from physics to computer vision and pattern recognition fields, and demonstrate that Legendre polynomials can help to reduce the computational cost of NCC based template matching significantly.
Le dispositif, un incontournable du moment
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Françoise Demaizière
2008-03-01
Full Text Available 1.Introduction Je proposerai ci-après quelques réflexions à partir d'un terme qui est devenu omniprésent mais dont la définition et l'interprétation sont, me semble-t-il, assez variables. De telles variations sont courantes et ne sont pas forcément un obstacle majeur à l'action et à la réflexion. Il n'est toutefois pas inintéressant de s'arrêter un moment sur le ou les dispositifs d'apprentissage, de formation, multimédia, pédagogiques… 2.Omniprésence du terme, du mécanique au juridique et à ...
Magnetic-Moment Fragmentation and Monopole Crystallization
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M. E. Brooks-Bartlett
2014-01-01
Full Text Available The Coulomb phase, with its dipolar correlations and pinch-point–scattering patterns, is central to discussions of geometrically frustrated systems, from water ice to binary and mixed-valence alloys, as well as numerous examples of frustrated magnets. The emergent Coulomb phase of lattice-based systems has been associated with divergence-free fields and the absence of long-range order. Here, we go beyond this paradigm, demonstrating that a Coulomb phase can emerge naturally as a persistent fluctuating background in an otherwise ordered system. To explain this behavior, we introduce the concept of the fragmentation of the field of magnetic moments into two parts, one giving rise to a magnetic monopole crystal, the other a magnetic fluid with all the characteristics of an emergent Coulomb phase. Our theory is backed up by numerical simulations, and we discuss its importance with regard to the interpretation of a number of experimental results.
General moment theorems for nondistinct unrestricted partitions
Coons, Michael; Kirsten, Klaus
2009-01-01
A well-known result from Hardy and Ramanujan ["Aysmptotic formulae in combinatory analysis," Proc. Lond. Math. Soc. 17, 75 (1918)] gives an asymptotic expression for the number of possible ways to express an integer as the sum of smaller integers. In this vein, we consider the general partitioning problem of writing an integer n as a sum of summands from a given sequence Λ of nondecreasing integers. Under suitable assumptions on the sequence Λ, we obtain results using associated zeta functions and saddle-point techniques. We also calculate higher moments of the sequence Λ as well as the expected number of summands. Applications are made to various sequences, including those of Barnes and Epstein types. These results are of potential interest in statistical mechanics in the context of Bose-Einstein condensation.
Axially Ligated Phthalocyanine Conductors with Magnetic Moments
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Tamotsu Inabe
2017-04-01
Full Text Available This mini-review describes electrical conductivity, magnetic properties, and magnetotransport properties of one-dimensional partially oxidized salts composed of axially ligated phthalocyanines, TPP[M(Pc(CN2]2 (TPP = tetraphenylphosphonium, Pc = phthalocyaninato, with M of Fe (d5, S = 1/2 and Cr (d3, S = 3/2. These salts are isomorphous, and π–π interactions in the crystal, that becomes the origin of the charge carriers, are nearly the same. Both the Fe and Cr salts show carrier localization and charge disproportionation which is enhanced by the interaction between local magnetic moments and conduction π-electrons (π–d interaction. However, the magnetic properties are slightly different between them. M = Fe has been found to show unique anisotropic magnetic properties and antiferromagnetic short-range magnetic order between the d-spins. On the other hand, for M = Cr, its magnetic moment is isotropic. Temperature dependence of the magnetic susceptibility shows typical Curie–Weiss behavior with negative Weiss temperature, but the exchange interaction is complicated. Both M = Fe and M = Cr show large negative magnetoresistance, reflecting the difference in the anisotropy. The magnetoresistance ratio (MR is larger in the Fe system than in the Cr system in the low magnetic field range, but MR in the Cr system exceeds that in the Fe system when the magnetic field becomes higher than 15 T. We discuss the mechanism of the giant negative magnetoresistance with reference to the d–d, π–d, and π–π interactions.
Electron Excitation of High Dipole Moment Molecules
Goldsmith, Paul; Kauffmann, Jens
2018-01-01
Emission from high-dipole moment molecules such as HCN allows determination of the density in molecular clouds, and is often considered to trace the “dense” gas available for star formation. We assess the importance of electron excitation in various environments. The ratio of the rate coefficients for electrons and H2 molecules, ~10^5 for HCN, yields the requirements for electron excitation to be of practical importance if n(H2) 10^{-5}, where the numerical factors reflect critical values n_c(H2) and X^*(e-). This indicates that in regions where a large fraction of carbon is ionized, X(e-) will be large enough to make electron excitation significant. The situation is in general similar for other “high density tracers”, including HCO+, CN, and CS. But there are significant differences in the critical electron fractional abundance, X^*(e-), defined by the value required for equal effect from collisions with H2 and e-. Electron excitation is, for example, unimportant for CO and C+. Electron excitation may be responsible for the surprisingly large spatial extent of the emission from dense gas tracers in some molecular clouds (Pety et al. 2017, Kauffmann, Goldsmith et al. 2017, A&A, submitted). The enhanced estimates for HCN abundances and HCN/CO and HCN/HCO+ ratios observed in the nuclear regions of luminous galaxies may be in part a result of electron excitation of high dipole moment tracers. The importance of electron excitation will depend on detailed models of the chemistry, which may well be non-steady state and non--static.
The perfect message at the perfect moment.
Kalyanam, Kirthi; Zweben, Monte
2005-11-01
Marketers planning promotional campaigns ask questions to boost the odds that the messages will be accepted: Who should receive each message? What should be its content? How should we deliver it? The one question they rarely ask is, when should we deliver it? That's too bad, because in marketing, timing is arguably the most important variable of all. Indeed, there are moments in a customer's relationship with a business when she wants to communicate with that business because something has changed. If the company contacts her with the right message in the right format at the right time, there's a good chance of a warm reception. The question of "when" can be answered by a new computer-based model called "dialogue marketing," which is, to date, the highest rung on an evolutionary ladder that ascends from database marketing to relationship marketing to one-to-one marketing. Its principle advantages over older approaches are that it is completely interactive, exploits many communication channels, and is "relationship aware": that is, it continuously tracks every nuance of the customer's interaction with the business. Thus, dialogue marketing responds to each transition in that relationship at the moment the customer requires attention. Turning a traditional marketing strategy into a dialogue-marketing program is a straightforward matter. Begin by identifying the batch communications you make with customers, then ask yourself what events could trigger those communications to make them more timely. Add a question or call to action to each message and prepare a different treatment or response for each possible answer. Finally, create a series of increasingly urgent calls to action that kick in if the question or call to action goes unanswered by the customer. As dialogue marketing proliferates, it may provide the solid new footing that Madison Avenue seeks.
Valeriánová, Anna; Crhová, Lenka; Holtanová, Eva; Kašpar, Marek; Můller, Miloslav; Kyselý, Jan; Stříž, Martin
2014-05-01
Assessment of the quantity and extremity of extreme precipitation is important for many sectors, especially for hydrology and geology. In present contribution we focus on precipitation leading to the flood events during May and June 2013 in the Czech Republic. The first extreme precipitation event was connected with cyclone above central Europe. The significant precipitation occurred mainly in the western and central part of the Czech Republic. On 1/6/2013 we recorded in some places 1-day precipitation amounts over 100 mm. The return period of 1-day precipitation exceeded 100 years at some stations. The second extreme precipitation event on 24/6 and 25/6/2013 affected eastern and northern part of the Czech Republic. The precipitation amounts were not as high as in the beginning of June, but in some places 2-day precipitation amount exceeded 100 mm. We compare the extremity of observed precipitation amounts with those that caused the significant floods in 2010, 2002 and 1997 using the Weather Extremity Index which evaluates the extremity (based on return periods) and spatial extent of the meteorological extreme event of interest. The generalized extreme value (GEV) distribution is used as the parametric model for annual maxima of 1-day to 7-day precipitation amounts. Parameters of the GEV distribution are estimated by the L-moment algorithm and the region-of-influence method. The work has been supported by the grant P209/11/1990 funded by the Czech Science Foundation.
Multivariate log-skew-elliptical distributions with applications to precipitation data
Marchenko, Yulia V.
2009-07-13
We introduce a family of multivariate log-skew-elliptical distributions, extending the list of multivariate distributions with positive support. We investigate their probabilistic properties such as stochastic representations, marginal and conditional distributions, and existence of moments, as well as inferential properties. We demonstrate, for example, that as for the log-t distribution, the positive moments of the log-skew-t distribution do not exist. Our emphasis is on two special cases, the log-skew-normal and log-skew-t distributions, which we use to analyze US national (univariate) and regional (multivariate) monthly precipitation data. © 2009 John Wiley & Sons, Ltd.
Effective field theory, electric dipole moments and electroweak baryogenesis
Balazs, Csaba; White, Graham; Yue, Jason
2017-03-01
Negative searches for permanent electric dipole moments (EDMs) heavily constrain models of baryogenesis utilising various higher dimensional charge and parity violating (CPV) operators. Using effective field theory, we create a model independent connection between these EDM constraints and the baryon asymmetry of the universe (BAU) produced during a strongly first order electroweak phase transition. The thermal aspects of the high scale physics driving the phase transition are paramaterised by the usual kink solution for the bubble wall profile. We find that operators involving derivatives of the Higgs field yield CPV contributions to the BAU containing derivatives of the Higgs vacuum expectation value (vev), while non-derivative operators lack such contributions. Consequently, derivative operators cannot be eliminated in terms of non-derivative operators (via the equations of motion) if one is agnostic to the new physics that leads to the phase transition. Thus, we re-classify the independent dimension six operators, restricting ourselves to third generation quarks, gauge bosons and the Higgs. Finally, we calculate the BAU (as a function of the bubble wall width and the cutoff) for a derivative and a non-derivative operator, and relate it to the EDM constraints.
Endogenous opioids regulate moment-to-moment neuronal communication and excitability.
Winters, Bryony L; Gregoriou, Gabrielle C; Kissiwaa, Sarah A; Wells, Oliver A; Medagoda, Danashi I; Hermes, Sam M; Burford, Neil T; Alt, Andrew; Aicher, Sue A; Bagley, Elena E
2017-03-22
Fear and emotional learning are modulated by endogenous opioids but the cellular basis for this is unknown. The intercalated cells (ITCs) gate amygdala output and thus regulate the fear response. Here we find endogenous opioids are released by synaptic stimulation to act via two distinct mechanisms within the main ITC cluster. Endogenously released opioids inhibit glutamate release through the δ-opioid receptor (DOR), an effect potentiated by a DOR-positive allosteric modulator. Postsynaptically, the opioids activate a potassium conductance through the μ-opioid receptor (MOR), suggesting for the first time that endogenously released opioids directly regulate neuronal excitability. Ultrastructural localization of endogenous ligands support these functional findings. This study demonstrates a new role for endogenously released opioids as neuromodulators engaged by synaptic activity to regulate moment-to-moment neuronal communication and excitability. These distinct actions through MOR and DOR may underlie the opposing effect of these receptor systems on anxiety and fear.
Hourly and Daily Precipitation Data
National Oceanic and Atmospheric Administration, Department of Commerce — Precipitation reports submitted on many form types, including tabular and autographic charts. Reports are almost exclusively from the US Cooperative Observer Network.
Electrostatic precipitators for industrial applications
Francis, Steve L; Bradburn, Keith M
2014-01-01
This Guidebook provides basic knowledge of the physics and power supplies of electrostatic precipitators. It also deals with practical aspects of ESP design and gives examples of typical applications of ESPs.
Atrial Ectopics Precipitating Atrial Fibrillation
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Johnson Francis
2015-04-01
Full Text Available Holter monitor tracing showing blocked atrial ectopics and atrial ectopic precipitating atrial fibrillation is being demonstrated. Initially it was coarse atrial fibrillation, which rapidly degenerated into fine atrial fibrillation.
Environmental Radioactivity, Temperature, and Precipitation.
Riland, Carson A.
1996-01-01
Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)
Identifying Anomality in Precipitation Processes
Jiang, P.; Zhang, Y.
2014-12-01
Safety, risk and economic analyses of engineering constructions such as storm sewer, street and urban drainage, and channel design are sensitive to precipitation storm properties. Whether the precipitation storm properties exhibit normal or anomalous characteristics remains obscure. In this study, we will decompose a precipitation time series as sequences of average storm intensity, storm duration and interstorm period to examine whether these sequences could be treated as a realization of a continuous time random walk with both "waiting times" (interstorm period) and "jump sizes" (average storm intensity and storm duration). Starting from this viewpoint, we will analyze the statistics of storm duration, interstorm period, and average storm intensity in four regions in southwestern United States. We will examine whether the probability distribution is temporal and spatial dependent. Finally, we will use fractional engine to capture the randomness in precipitation storms.
Analytical Derivation of Moment Equations in Stochastic Chemical Kinetics
Sotiropoulos, Vassilios; Kaznessis, Yiannis N.
2011-01-01
The master probability equation captures the dynamic behavior of a variety of stochastic phenomena that can be modeled as Markov processes. Analytical solutions to the master equation are hard to come by though because they require the enumeration of all possible states and the determination of the transition probabilities between any two states. These two tasks quickly become intractable for all but the simplest of systems. Instead of determining how the probability distribution changes in time, we can express the master probability distribution as a function of its moments, and, we can then write transient equations for the probability distribution moments. In 1949, Moyal defined the derivative, or jump, moments of the master probability distribution. These are measures of the rate of change in the probability distribution moment values, i.e. what the impact is of any given transition between states on the moment values. In this paper we present a general scheme for deriving analytical moment equations for any N-dimensional Markov process as a function of the jump moments. Importantly, we propose a scheme to derive analytical expressions for the jump moments for any N-dimensional Markov process. To better illustrate the concepts, we focus on stochastic chemical kinetics models for which we derive analytical relations for jump moments of arbitrary order. Chemical kinetics models are widely used to capture the dynamic behavior of biological systems. The elements in the jump moment expressions are a function of the stoichiometric matrix and the reaction propensities, i.e the probabilistic reaction rates. We use two toy examples, a linear and a non-linear set of reactions, to demonstrate the applicability and limitations of the scheme. Finally, we provide an estimate on the minimum number of moments necessary to obtain statistical significant data that would uniquely determine the dynamics of the underlying stochastic chemical kinetic system. The first two moments
Properties of Orthogonal Gaussian-Hermite Moments and Their Applications
Directory of Open Access Journals (Sweden)
Jun Shen
2005-03-01
Full Text Available Moments are widely used in pattern recognition, image processing, and computer vision and multiresolution analysis. In this paper, we first point out some properties of the orthogonal Gaussian-Hermite moments, and propose a new method to detect the moving objects by using the orthogonal Gaussian-Hermite moments. The experiment results are reported, which show the good performance of our method.
Zernike moments features for shape-based gait recognition
Qin, Huanfeng; Qin, Lan; Liu, Jun; Chao, Jiang
2011-12-01
The paper proposes a new spatio-temporal gait representation, called cycles gait Zernike moments (CGZM), to characterize human walking properties for individual recognition. Firstly, Zernike moments as shape descriptors are used to characterize gait silhouette shape. Secondly, we generate CGZM from Zernike moments of silhouette sequences. Finally, the phase and magnitude coefficientsof CGZM are utilized to perform classification by the modified Hausdorff distance (MHD) classifier. Experimental results show that the proposed approach have an encouraging recognition performance.
Study upon the Moment of Ovulation in Sows to Establish the Optimum Moment for Semen Inoculation
Directory of Open Access Journals (Sweden)
Mariana Sandu
2012-05-01
Full Text Available Efficiency of artificial insemination depends equaly by semen quality and time of inoculation. The optimal time for inoculation was calculated usually from the moment of detection of heat, for double insemination, so that one of the two inoculations to approach the time of ovulation. To increase the efficiency of boars exploitation is necesary to change the method to a single insemination. To ensure normal fertility parameters with only one inoculation it is necessary to chose with great precision the moment of insemination ,in order to ensure the time for sperm capacitation and penetration of viable oocytes. Starting from the fact that major events such as forrowing and death occur, according to the circadian rhythm, in the second half of the night, this study aims to detect from this point of view the moment of ovulation, to find a more reliable calculation for the time of semen inoculation. The experiments were conducted on puberal gilts, which were not treated for induction of ovulation; the control for detecting the follicular dehiscence was done only on physiological oestrus. Females having symptoms at heat control were subject to series of laparatomias, complete with collection and examination of oocytes.
Higher Moments of Weighted Integrals of Non-Gaussian Fields
DEFF Research Database (Denmark)
Mohr, Gunnar
1996-01-01
In general , the exact probability distribution of a definite non-Gaussian random field is not known. Some information about this unknown distribution can be obtained from the 3rd and 4th moment of the integral. Approximations to these moments are calculated by a numerical technique based...... on recursive application of Winterstein approximations) moment fitted linear combinations of Hermite Polynomials of standard Gaussian variables). By use of computerized symbol manipulations it is practicable to obtain exact moments (up to order 4) of partial weighted sums of mutually dependent variables...
Extension of moment projection method to the fragmentation process
Energy Technology Data Exchange (ETDEWEB)
Wu, Shaohua [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Yapp, Edward K.Y.; Akroyd, Jethro; Mosbach, Sebastian [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); Xu, Rong [School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore); Yang, Wenming [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Kraft, Markus, E-mail: mk306@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore)
2017-04-15
The method of moments is a simple but efficient method of solving the population balance equation which describes particle dynamics. Recently, the moment projection method (MPM) was proposed and validated for particle inception, coagulation, growth and, more importantly, shrinkage; here the method is extended to include the fragmentation process. The performance of MPM is tested for 13 different test cases for different fragmentation kernels, fragment distribution functions and initial conditions. Comparisons are made with the quadrature method of moments (QMOM), hybrid method of moments (HMOM) and a high-precision stochastic solution calculated using the established direct simulation algorithm (DSA) and advantages of MPM are drawn.
The Electric Dipole Moment of the Electron
Commins, Eugene D.; Demille, David
The following sections are included: * Introduction * Overview of relevant particle theory * Electron EDM in the Standard Model * Electron EDM in extensions of the Standard Model * Introduction to experimental basis for electron EDM searches * Other sources of atomic and molecular EDMs * Theoretical Basis of Electron EDM Experiments * Proper-Lorentz-invariant EDM Lagrangian density * Schiff's theorem * Enhancement factors for paramagnetic atoms * Is there a simple intuitive explanation for the Sandars effect? * P,T-odd electron-nucleon interaction * Paramagnetic molecules * Electron EDM Experiments * General overview * A simple model experiment * Noise * Systematic errors * The Berkeley thallium atomic beam experiment * Cesium optical pumping experiments * Cesium optical trap experiments * The francium optical trap experiment * The YbF experiment * The PbO experiment * The ThO experiment * The proposed HfF+ experiment * Electron EDM solid-state experiments * Basic ideas * The Indiana GGG experiment * The Amherst GdIG experiment * Atomic T,P-odd polarizability. Molecular T,P-odd magnetic moment * Acknowledgments * References
The moment of proof mathematical epiphanies
Benson, Donald C
2000-01-01
When Archimedes, while bathing, suddenly hit upon the principle of buoyancy, he ran wildly through the streets of Syracuse, stark naked, crying "eureka!" In The Moment of Proof, Donald Benson attempts to convey to general readers the feeling of eureka--the joy of discovery--that mathematicians feel when they first encounter an elegant proof. This is not an introduction to mathematics so much as an introduction to the pleasures of mathematical thinking. And indeed the delights of this book are many and varied. The book is packed with intriguing conundrums--Loyd''s Fifteen Puzzle, the Petersburg Paradox, the Chaos Game, the Monty Hall Problem, the Prisoners'' Dilemma--as well as many mathematical curiosities. We learn how to perform the arithmetical proof called "casting out nines" and are introduced to Russian peasant multiplication, a bizarre way to multiply numbers that actually works. The book shows us how to calculate the number of ways a chef can combine ten or fewer spices to flavor his soup (1,024) and ...
Electric Dipole Moments in the MSSM Reloaded
Ellis, Jonathan Richard; Pilaftsis, Apostolos
2008-01-01
We present a detailed study of the Thallium, neutron, Mercury and deuteron electric dipole moments (EDMs) in the CP-violating Minimal Supersymmetric extension of the Standard Model (MSSM). We take into account the complete set of one-loop graphs, the dominant Higgs-mediated two-loop diagrams, the complete CP-odd dimension-six Weinberg operator and the Higgs-mediated four-fermion operators. We improve upon earlier calculations by including the resummation effects due to CP-violating Higgs-boson mixing and to threshold corrections to the Yukawa couplings of all up- and down-type quarks and charged leptons. As an application of our study, we analyse the EDM constraints on the CPX, trimixing and Maximally CP- and Minimally Flavour-Violating (MCPMFV) scenarios. Cancellations may occur among the CP-violating contributions to the three measured EDMs arising from the 6 CP-violating phases in the MCPMFV scenario, leaving open the possibility of relatively large contributions to other CP-violating observables. The anal...
Magnetic depth profiling of Fe/Au multilayer using neutron ...
Indian Academy of Sciences (India)
Au multilayer sample for characterizing the layer structure and magnetic moment density profile. Fe/Au multilayer shows strong spin-dependent scattering at interfaces, making it a prospective GMR material. Fe/Au multilayer with bilayer ...
A novel computational framework for deducing muscle synergies from experimental joint moments
Directory of Open Access Journals (Sweden)
Anantharaman eGopalakrishnan
2014-12-01
Full Text Available Prior experimental studies have hypothesized the existence of a ‘muscle synergy’ based control scheme for producing limb movements and locomotion in vertebrates. Such synergies have been suggested to consist of fixed muscle grouping schemes with the co-activation of all muscles in a synergy resulting in limb movement. Quantitative representations of these groupings (termed muscle weightings and their control signals (termed synergy controls have traditionally been derived by the factorization of experimentally measured EMG. This study presents a novel approach for deducing these weightings and controls from inverse dynamic joint moments that are computed from an alternative set of experimental measurements – movement kinematics and kinetics. This technique was applied to joint moments for healthy human walking at 0.7 and 1.7 m/s, and two sets of ‘simulated’ synergies were computed based on two different criteria (1 synergies were required to minimize errors between experimental and simulated joint moments in a musculoskeletal model (pure-synergy solution (2 along with minimizing joint moment errors, synergies also minimized muscle activation levels (optimal-synergy solution. On comparing the two solutions, it was observed that the introduction of optimality requirements (optimal-synergy to a control strategy solely aimed at reproducing the joint moments (pure-synergy did not necessitate major changes in the muscle grouping within synergies or the temporal profiles of synergy control signals. Synergies from both the simulated solutions exhibited many similarities to EMG derived synergies from a previously published study, thus implying that the analysis of the two different types of experimental data reveals similar, underlying synergy structures.
The Global Precipitation Measurement Mission
Jackson, Gail
2014-05-01
The Global Precipitation Measurement (GPM) mission's Core satellite, scheduled for launch at the end of February 2014, is well designed estimate precipitation from 0.2 to 110 mm/hr and to detect falling snow. Knowing where and how much rain and snow falls globally is vital to understanding how weather and climate impact both our environment and Earth's water and energy cycles, including effects on agriculture, fresh water availability, and responses to natural disasters. The design of the GPM Core Observatory is an advancement of the Tropical Rainfall Measuring Mission (TRMM)'s highly successful rain-sensing package [3]. The cornerstone of the GPM mission is the deployment of a Core Observatory in a unique 65o non-Sun-synchronous orbit to serve as a physics observatory and a calibration reference to improve precipitation measurements by a constellation of 8 or more dedicated and operational, U.S. and international passive microwave sensors. The Core Observatory will carry a Ku/Ka-band Dual-frequency Precipitation Radar (DPR) and a multi-channel (10-183 GHz) GPM Microwave Radiometer (GMI). The DPR will provide measurements of 3-D precipitation structures and microphysical properties, which are key to achieving a better understanding of precipitation processes and improving retrieval algorithms for passive microwave radiometers. The combined use of DPR and GMI measurements will place greater constraints on possible solutions to radiometer retrievals to improve the accuracy and consistency of precipitation retrievals from all constellation radiometers. Furthermore, since light rain and falling snow account for a significant fraction of precipitation occurrence in middle and high latitudes, the GPM instruments extend the capabilities of the TRMM sensors to detect falling snow, measure light rain, and provide, for the first time, quantitative estimates of microphysical properties of precipitation particles. The GPM Core Observatory was developed and tested at NASA
Miniature, Variable-Speed Control Moment Gyroscope
Bilski, Steve; Kline-Schoder, Robert; Sorensen, Paul
2011-01-01
The Miniature Variable-Speed Control Moment Gyroscope (MVS-CMG) was designed for small satellites (mass from less than 1 kg up to 500 kg). Currently available CMGs are too large and heavy, and available miniature CMGs do not provide sufficient control authority for use on practical satellites. This primarily results from the need to greatly increase the speed of rotation of the flywheel in order to reduce the flywheel size and mass. This goal was achieved by making use of a proprietary, space-qualified, high-speed (100,000 rpm) motor technology to spin the flywheel at a speed ten times faster than other known miniature CMGs under development. NASA is supporting innovations in propulsion, power, and guidance and navigation systems for low-cost small spacecraft. One of the key enabling technologies is attitude control mechanisms. CMGs are particularly attractive for spacecraft attitude control since they can achieve higher torques with lower mass and power than reaction wheels, and they provide continuous torque capability that enables precision pointing (in contrast to on-off thruster control). The aim of this work was to develop a miniature, variable-speed CMG that is sized for use on small satellites. To achieve improved agility, these spacecraft must be able to slew at high rate, which requires attitude control actuators that can apply torques on the order of 5 N-m. The MVS-CMG is specifically designed to achieve a high-torque output with a minimum flywheel and system mass. The flywheel can be run over a wide range of speeds, which is important to help reduce/eliminate potential gimbal lock, and can be used to optimize the operational envelope of the CMG.
Elliptic integral evaluations of Bessel moments
Energy Technology Data Exchange (ETDEWEB)
Bailey, David H.; Borwein, Jonathan M.; Broadhurst, David; Glasser, M.L.
2008-01-06
We record what is known about the closed forms for variousBessel function moments arising in quantum field theory, condensed mattertheory and other parts of mathematical physics. More generally, wedevelop formulae for integrals of products of six or fewer Besselfunctions. In consequence, we are able to discover and prove closed formsfor c(n,k) := Int_0 inf tk K_0 n(t) dt, with integers n = 1, 2, 3, 4 andk greater than or equal to 0, obtaining new results for the even momentsc3,2k and c4,2k . We also derive new closed forms for the odd momentss(n,2k+1) := Int_0 inf t(2k+1) I_0(t) K_0n(t) dt,with n = 3, 4 and fort(n,2k+1) := Int_0 inf t(2k+1) I_02(t) K_0(n-2) dt, with n = 5, relatingthe latter to Green functions on hexagonal, diamond and cubic lattices.We conjecture the values of s(5,2k+1), make substantial progress on theevaluation of c(5,2k+1), s(6,2k+1) and t(6,2k+1) and report more limitedprogress regarding c(5,2k), c(6,2k+1) and c(6,2k). In the process, weobtain 8 conjectural evaluations, each of which has been checked to 1200decimal places. One of these lies deep in 4-dimensional quantum fieldtheory and two are probably provable by delicate combinatorics. Thereremains a hard core of five conjectures whose proofs would be mostinstructive, to mathematicians and physicists alike.
A sparse flat extension theorem for moment matrices
M. Laurent (Monique); B. Mourrain
2008-01-01
htmlabstractIn this note we prove a generalization of the flat extension theorem of Curto and Fialkow [4] for truncated moment matrices. It applies to moment matrices indexed by an arbitrary set of monomials and its border, assuming that this set is connected to 1. When formulated in a basis-free
A generalized flat extension theorem for moment matrices
M. Laurent (Monique); B. Mourrain
2009-01-01
htmlabstractIn this note we prove a generalization of the flat extension theorem of Curto and Fialkow [4] for truncated moment matrices. It applies to moment matrices indexed by an arbitrary set of monomials and its border, assuming that this set is connected to 1. When formulated in a basis-free
Score Function of Distribution and Revival of the Moment Method
Czech Academy of Sciences Publication Activity Database
Fabián, Zdeněk
2016-01-01
Roč. 45, č. 4 (2016), s. 1118-1136 ISSN 0361-0926 R&D Projects: GA MŠk(CZ) LG12020 Institutional support: RVO:67985807 Keywords : characteristics of distributions * data characteristics * general moment method * Huber moment estimator * parametric methods * score function Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.311, year: 2016
Wigner distribution moments in fractional Fourier transform systems.
Bastiaans, Martin J; Alieva, Tatiana
2002-09-01
It is shown how all global Wigner distribution moments of arbitrary order in the output plane of a (generally anamorphic) two-dimensional fractional Fourier transform system can be expressed in terms of the moments in the input plane. Since Wigner distribution moments are identical to derivatives of the ambiguity function at the origin, a similar relation holds for these derivatives. The general input-output relationship is then broken down into a number of rotation-type input-output relationships between certain combinations of moments. It is shown how the Wigner distribution moments (or ambiguity function derivatives) can be measured as intensity moments in the output planes of a set of appropriate fractional Fourier transform systems and thus be derived from the corresponding fractional power spectra. The minimum number of (anamorphic) fractional power spectra that are needed for the determination of these moments is derived. As an important by-product we get a number of moment combinations that are invariant under (anamorphic) fractional Fourier transformation.
Factorial moment -generating function and the Pascal distribution ...
African Journals Online (AJOL)
Given a distribution, the cumulants or factorial moments can be used to obtain the skewness and kurtosis which in turn are used to determine the normal approximation of the given distribution. It is shown in this paper that for the Pascal Distribution, the factorial moment generating function provides a simpler technique.
Spin Structure Moments of the Proton and Deuteron
Slifer, K; Aghalaryan, A; Ahmidouch, A; Asaturyan, R; Bloch, F; Boeglin, W; Bosted, P; Carasco, C; Carlini, R; Cha, J; Chen, J P; Christy, M E; Cole, L; Coman, L; Crabb, D; Danagulyan, S; Day, D; Dunne, J; Elaasar, M; Ent, R; Fenker, H; Frlez, E; Gaskell, D; Gan, L; Gómez, J; Hu, B; Jourdan, J; Jones, M K; Keith, C; Keppel, C E; Khandaker, M; Klein, A; Kramer, L; Liang, Y; Lichtenstadt, J; Lindgren, R; Mack, D; McKee, P; McNulty, D; Meekins, D; Mkrtchyan, H; Nasseripour, R; Niculescu, I; Normand, K; Norum, B; Pocanic, D; Prok, Y; Raue, B; Reinhold, J; Roche, J; Kiselev, D; Savvinov, N; Sawatzky, B; Seely, M; Sick, I; Smith, C; Smith, G; Stepanyan, S; Tang, L; Tajima, S; Testa, G; Vulcan, W; Wang, K; Warren, G; Wesselmann, F R; Wood, S; Yan, C; Yuan, L; Yun, J; Zeier, M; Zhu, H
2008-01-01
Moments of the spin structure functions g1 and g2 of the proton and deuteron have been measured in the resonance region at intermediate four momentum transfer. We perform a Nachtmann moment analysis of this data, along with isovector and isoscalar combinations, in order to rigorously account for target mass effects. This analysis provides the first definitive evidence for dynamic higher twists.
Space-charge electrostatic precipitation
Energy Technology Data Exchange (ETDEWEB)
Middleton, C.E.
1977-05-01
An improved electrostatic precipitator called a space charge precipitator was tested and studied. A space charge precipitator differs from a conventional model in that the fields necessary to move the particles from the gas to the collecting surfaces are provided by a cloud of charged innocuous drops, such as glycerine or water, rather than by a charged electrode system. The flow conditions, electrical equipment, and physical dimensions of the test precipitator are typical of industrial applications. Experiments using water fog at a velocity of 10 ft/sec and a residence time of 0.6 sec, for a system charged at 25 kV, show a removal of iron oxide particles of approximately 52 percent. Theoretical calculations, assuming 2 micron particles, predict a removal of 50 percent. The results with glycerine fog are comparable. Experiments at various flowrates for both water fog and glycerine fog show a trend of decreasing particle removal for increasing flowrate. An identical trend is predicted by the space charge theory. Electron micrographs verify that only particles smaller than two microns are present in the laboratory precipitator.
A Comparison of Moments-Based Logo Recognition Methods
Directory of Open Access Journals (Sweden)
Zili Zhang
2014-01-01
Full Text Available Logo recognition is an important issue in document image, advertisement, and intelligent transportation. Although there are many approaches to study logos in these fields, logo recognition is an essential subprocess. Among the methods of logo recognition, the descriptor is very vital. The results of moments as powerful descriptors were not discussed before in terms of logo recognition. So it is unclear which moments are more appropriate to recognize which kind of logos. In this paper we find out the relations between logos with different transforms and moments, which moments are fit for logos with different transforms. The open datasets are employed from the University of Maryland. The comparisons based on moments are carried out from the aspects of logos with noise, and rotation, scaling, rotation and scaling.
Apple Shape Classification Method Based on Wavelet Moment
Directory of Open Access Journals (Sweden)
Jiangsheng Gui
2014-09-01
Full Text Available Shape is not only an important indicator for assessing the grade of the apple, but also the important factors for increasing the value of the apple. In order to improve the apple shape classification accuracy rate, an approach for apple shape sorting based on wavelet moments was proposed, the image was first subjected to a normalization process using its regular moments to obtain scale and translation invariance, the rotation invariant wavelet moment features were then extracted from the scale and translation normalized images and the method of cluster analysis was used for finished the shape classification. This method performs better than traditional approaches such as Fourier descriptors and Zernike moments, because of that Wavelet moments can provide time-domain and frequency domain window, which was verified by experiments. The normal fruit shape, mild deformity and severe deformity classification accuracy is 86.21 %, 85.82 %, 90.81 % by our method.
Regional frequency analysis of extreme precipitation for Sicily (Italy)
Forestieri, Angelo; Blenkinsop, Stephen; Fowler, Hayley; Lo Conti, Francesco; Noto, Leonardo
2016-04-01
The analysis of extreme precipitation has always been included among most relevant hydrological applications because of the several important activities linked to the availability of tools for the estimation of extreme rainfall quantiles. These activities include the design of hydraulic civil structures and the evaluation and management of hydraulic and hydrological risk. In this study a frequency analysis of annual maxima precipitation measurements has been carried out for the area of Sicily (Italy). A typical hierarchical regional approach has been adopted for the parameter estimation procedure based on the L-moments method. The identification of homogeneous regions within the procedure has been pursued with a data driven procedure constituted by a principal component analysis of an ensemble of selected auxiliary variables, and a K-means cluster analysis algorithm. Auxiliary variables comprise meteo-climatic information and a representation of the average seasonal distribution of intense events. Results have been evaluated by means of a Monte Carlo experiment based on the comparison between at-site and regional fitted frequency distributions. Moreover, results have been compared with previous analyses performed for the same area. The study provides an updated tool for the modelling of extreme precipitation for the area of Sicily (Italy), with different features respect to previous tools both in terms of definition of homogeneous zones and in terms of parameters of the frequency distribution. Meteo-climatic information and the seasonality of extreme events retrieved from the dataset has been proficuously exploited in the analysis.
Geng, Haopeng; Pan, Baotian; Huang, Bo; Cao, Bo; Gao, Hongshan
2017-11-01
The mutual interrelation of orographic precipitation pattern and topography is key to understanding the competing role of tectonics and climate in landscape evolution. However, the relationship between precipitation and topography across arid to semiarid orogens has received little attention because of limited data availability. As a global successor to Tropical Rainfall Measuring Mission (TRMM), the Global Precipitation Measurement (GPM) extends precipitation measurements to mid- and high latitudes since 2014. In this study, we process one year of GPM precipitation with a spatial resolution of 0.1° × 0.1° across the arid to semiarid Qilian Shan Mountains to examine the spatial correlation between topography and precipitation. Though short, this data set provides reasonable precipitation when compared with other weather station relevant estimates. We then use nine orogen-perpendicular swath profiles to examine the influence of topography on precipitation distribution through the range. The results show that precipitation variation displays a significant elevation control with precipitation peaks in the high elevation mountain interior. We further compare the GPM precipitation with elevation and local relief within each swath extent. The results show that precipitation uniformly increases with increasing elevation for nine swaths, which is consistent with the elevation-controlled precipitation pattern. We find precipitation and local relief are positively correlated for five swaths but not for the remaining four swaths. Based on published data for uplift and erosion, we suggest that the presence or absence of such a correlation indicates whether mountains are in topographic steady state or in a transient state of relief production.
Complexing-precipitating geochemical barriers
Savenko, A. V.
2017-02-01
New types of geochemical barriers on which chemical elements are immobilized as a result of combined complex formation and precipitation of barely soluble mineral phases are examined. A significant concentration of major components (Fe, Al) forming more stable complexes than an immobilized component X in the material is a necessary condition for this type of geochemical barriers. Filtration of the solution through a geochemical barrier is accompanied by substitution of X in the complex with a major component. As a result, the activity of X in the free state increases, and one barely soluble mineral phase or another of the component X precipitates when the state of saturation is achieved.
Shorey, Ryan C; Anderson, Scott; Lookatch, Samantha; Moore, Todd M; Stuart, Gregory L
2015-01-01
A growing body of research has examined the intersection of mindfulness and substance use, and a large body of research has examined the relation between mindfulness and anxiety. Unfortunately, no research has been conducted on the relation between mindfulness and anxiety symptoms among young adults (i.e., 18-25 years old) in treatment for substance use. The purpose of the current study was to examine the relation between one facet of mindfulness, moment-to-moment attention, and anxiety (panic and generalized anxiety) among young adults in treatment for substance use. Preexisting patient records from a residential substance use treatment center for young adults were reviewed (N = 148). Patient records were examined from May 2012 to August 2013, which represented all young adult patients admitted to the residential treatment facility during this time. Findings demonstrated that moment-to-moment mindful attention was associated with symptoms of panic disorder and generalized anxiety disorder even after controlling for gender, age, education, alcohol use, drug use, and the shared variance in generalized and panic symptoms. There were no gender differences in moment-to-moment mindful attention. These findings provide preliminary evidence that moment-to-moment mindful attention is associated with panic and generalized anxiety in young adults in substance use treatment. Combined with previous research on mindfulness-based interventions among adults in substance use treatment, research should examine the efficacy of mindfulness-based interventions for young adults in substance use treatment.
Bollinger, Sarah; Kreuter, Matthew W.
2012-01-01
In a randomized experiment using moment-to-moment audience analysis methods, we compared women's emotional responses with a narrative versus informational breast cancer video. Both videos communicated three key messages about breast cancer: (i) understand your breast cancer risk, (ii) talk openly about breast cancer and (iii) get regular…
Precipitation extreme changes exceeding moisture content increases in MIROC and IPCC climate models.
Sugiyama, Masahiro; Shiogama, Hideo; Emori, Seita
2010-01-12
Precipitation extreme changes are often assumed to scale with, or are constrained by, the change in atmospheric moisture content. Studies have generally confirmed the scaling based on moisture content for the midlatitudes but identified deviations for the tropics. In fact half of the twelve selected Intergovernmental Panel on Climate Change (IPCC) models exhibit increases faster than the climatological-mean precipitable water change for high percentiles of tropical daily precipitation, albeit with significant intermodel scatter. Decomposition of the precipitation extreme changes reveals that the variations among models can be attributed primarily to the differences in the upward velocity. Both the amplitude and vertical profile of vertical motion are found to affect precipitation extremes. A recently proposed scaling that incorporates these dynamical effects can capture the basic features of precipitation changes in both the tropics and midlatitudes. In particular, the increases in tropical precipitation extremes significantly exceed the precipitable water change in Model for Interdisciplinary Research on Climate (MIROC), a coupled general circulation model with the highest resolution among IPCC climate models whose precipitation characteristics have been shown to reasonably match those of observations. The expected intensification of tropical disturbances points to the possibility of precipitation extreme increases beyond the moisture content increase as is found in MIROC and some of IPCC models.
Investigating spousal influence using moment-to-moment affect data from marital conflict.
Madhyastha, Tara M; Hamaker, Ellen L; Gottman, John M
2011-04-01
Gottman and colleagues proposed using a dynamical systems model to study dyadic interaction in marriage. In this model, each spouse's affect in each 6-s window is described as a function of an uninfluenced linear steady state and a nonlinear influence function of the partner's affect in the previous window. Recently, an alternative parameter estimation procedure for the equations of marriage was introduced, which is based on threshold autoregressive models. We apply this estimation procedure to data from a study of couples (N = 124) and newlyweds (N = 130) to compare different forms of spousal influence using the Bayesian information criterion. Although results show some statistically significant evidence for influence, this is only slightly greater than what would be expected by random association. One model of influence does not fit all couples. This suggests that for many people initial state and emotional inertia dictate the outcome of the conflict discussion far more than the moment-to-moment affect of the spouse. This latter finding is in conflict with most models of couples' interaction, which suggest that the outcome of conflict discussions are determined by the nature of the couples' mutual influence processes.
Quantitating metabolites in protein precipitated serum using NMR spectroscopy.
Nagana Gowda, G A; Raftery, Daniel
2014-06-03
Quantitative NMR-based metabolite profiling is challenged by the deleterious effects of abundant proteins in the intact blood plasma/serum, which underscores the need for alternative approaches. Protein removal by ultrafiltration using low molecular weight cutoff filters thus represents an important step. However, protein precipitation, an alternative and simple approach for protein removal, lacks detailed quantitative assessment for use in NMR based metabolomics. In this study, we have comprehensively evaluated the performance of protein precipitation using methanol, acetonitrile, perchloric acid, and trichloroacetic acid and ultrafiltration approaches using 1D and 2D NMR, based on the identification and absolute quantitation of 44 human blood metabolites, including a few identified for the first time in the NMR spectra of human serum. We also investigated the use of a "smart isotope tag," (15)N-cholamine for further resolution enhancement, which resulted in the detection of a number of additional metabolites. (1)H NMR of both protein precipitated and ultrafiltered serum detected all 44 metabolites with comparable reproducibility (average CV, 3.7% for precipitation; 3.6% for filtration). However, nearly half of the quantified metabolites in ultrafiltered serum exhibited 10-74% lower concentrations; specifically, tryptophan, benzoate, and 2-oxoisocaproate showed much lower concentrations compared to protein precipitated serum. These results indicate that protein precipitation using methanol offers a reliable approach for routine NMR-based metabolomics of human blood serum/plasma and should be considered as an alternative to ultrafiltration. Importantly, protein precipitation, which is commonly used by mass spectrometry (MS), promises avenues for direct comparison and correlation of metabolite data obtained from the two analytical platforms to exploit their combined strength in the metabolomics of blood.
Kambayashi, Atsushi; Dressman, Jennifer B
2017-10-01
The aim of the current research was to determine the precipitation kinetics of dantrolene sodium using canine biorelevant in vitro testing and to model the precipitation kinetics by appropriately coupling the data with an in silico tool adapted for dogs. The precipitation profiles of dantrolene sodium solutions were obtained with the in vitro paddle apparatus at a revolution rate of 50rpm. The in silico prediction tool was designed using STELLA software and the predicted plasma concentration profiles of dantrolene using the in vitro precipitation data were compared with the observed in vivo pharmacokinetics in beagle dogs. The plasma profiles of dantrolene, which served as a model weakly acidic drug which precipitates in the upper gastrointestinal tract, was successfully predicted using the in vitro precipitation testing coupled with the in silico modeling and simulation approach. The approach was subsequently used to forecast the effect of pharmaceutical excipients (HPMC/PG) on the ability of the drug to supersaturate in the gut and the resulting pharmacokinetics. The agreement of the simulated pharmacokinetics with the observed values confirms the ability of canine biorelevant media to predict oral performance of enhanced dosage forms in dogs. Copyright © 2017 Elsevier B.V. All rights reserved.
Luck Reveals Stellar Explosion's First Moments
2008-05-01
Through a stroke of luck, astronomers have witnessed the first violent moments of a stellar explosion known as a supernova. Astronomers have seen thousands of these stellar explosions, but all previous supernovae were discovered days after the event had begun. This is the first time scientists have been able to study a supernova from its very beginning. Seeing one just moments after the event began is a major breakthrough that points the way to unraveling longstanding mysteries about how such explosions really work. Galaxy Before Supernova Explosion NASA's Swift satellite took these images of SN 2007uy in galaxy NGC 2770 before SN 2008D exploded. An X-ray image is on the left; image at right is in visible light. CREDIT: NASA/Swift Science Team/Stefan Immler. Large Image With Labels Large Image Without Labels Galaxy After Supernova Explosion On January 9, 2008, Swift caught a bright X-ray burst from an exploding star. A few days later, SN 2008D appeared in visible light. CREDIT: NASA/Swift Science Team/Stefan Immler. Large Image With Labels Large Image Without Labels "For years, we have dreamed of seeing a star just as it was exploding," said team leader Alicia Soderberg, a Hubble and Carnegie-Princeton Fellow at Princeton University. "This newly-born supernova is going to be the Rosetta Stone of supernova studies for years to come." Theorists had predicted for four decades that a bright burst of X-rays should be produced as the shock wave from a supernova blasts out of the star and through dense material surrounding the star. However, in order to see this burst, scientists faced the nearly-impossible challenge of knowing in advance where to point their telescopes to catch a supernova in the act of exploding. On January 9, luck intervened. Soderberg and her colleagues were making a scheduled observation of the galaxy NGC 2770, 88 million light-years from Earth, using the X-ray telescope on NASA's Swift satellite. During that observation, a bright burst of X
Utilizing the Vertical Variability of Precipitation to Improve Radar QPE
Gatlin, Patrick N.; Petersen, Walter A.
2016-01-01
Characteristics of the melting layer and raindrop size distribution can be exploited to further improve radar quantitative precipitation estimation (QPE). Using dual-polarimetric radar and disdrometers, we found that the characteristic size of raindrops reaching the ground in stratiform precipitation often varies linearly with the depth of the melting layer. As a result, a radar rainfall estimator was formulated using D(sub m) that can be employed by polarimetric as well as dual-frequency radars (e.g., space-based radars such as the GPM DPR), to lower the bias and uncertainty of conventional single radar parameter rainfall estimates by as much as 20%. Polarimetric radar also suffers from issues associated with sampling the vertical distribution of precipitation. Hence, we characterized the vertical profile of polarimetric parameters (VP3)-a radar manifestation of the evolving size and shape of hydrometeors as they fall to the ground-on dual-polarimetric rainfall estimation. The VP3 revealed that the profile of ZDR in stratiform rainfall can bias dual-polarimetric rainfall estimators by as much as 50%, even after correction for the vertical profile of reflectivity (VPR). The VP3 correction technique that we developed can improve operational dual-polarimetric rainfall estimates by 13% beyond that offered by a VPR correction alone.
A Study of Moment Based Features on Handwritten Digit Recognition
Directory of Open Access Journals (Sweden)
Pawan Kumar Singh
2016-01-01
Full Text Available Handwritten digit recognition plays a significant role in many user authentication applications in the modern world. As the handwritten digits are not of the same size, thickness, style, and orientation, therefore, these challenges are to be faced to resolve this problem. A lot of work has been done for various non-Indic scripts particularly, in case of Roman, but, in case of Indic scripts, the research is limited. This paper presents a script invariant handwritten digit recognition system for identifying digits written in five popular scripts of Indian subcontinent, namely, Indo-Arabic, Bangla, Devanagari, Roman, and Telugu. A 130-element feature set which is basically a combination of six different types of moments, namely, geometric moment, moment invariant, affine moment invariant, Legendre moment, Zernike moment, and complex moment, has been estimated for each digit sample. Finally, the technique is evaluated on CMATER and MNIST databases using multiple classifiers and, after performing statistical significance tests, it is observed that Multilayer Perceptron (MLP classifier outperforms the others. Satisfactory recognition accuracies are attained for all the five mentioned scripts.
Electrostatic Precipitator (ESP) TRAINING MANUAL
The manual assists engineers in using a computer program, the ESPVI 4.0W, that models all elements of an electrostatic precipitator (ESP). The program is a product of the Electric Power Research Institute and runs in the Windows environment. Once an ESP is accurately modeled, the...
Acid Precipitation: Causes and Consequences.
Babich, Harvey; And Others
1980-01-01
This article is the first of three articles in a series on the acid rain problem in recent years. Discussed are the causes of acid precipitation and its consequences for the abiotic and biotic components of the terrestrial and aquatic ecosystems, and for man-made materials. (Author/SA)
Waste and Simulant Precipitation Issues
Energy Technology Data Exchange (ETDEWEB)
Steele, W.V.
2000-11-29
As Savannah River Site (SRS) personnel have studied methods of preparing high-level waste for vitrification in the Defense Waste Processing Facility (DWPF), questions have arisen with regard to the formation of insoluble waste precipitates at inopportune times. One option for decontamination of the SRS waste streams employs the use of an engineered form of crystalline silicotitanate (CST). Testing of the process during FY 1999 identified problems associated with the formation of precipitates during cesium sorption tests using CST. These precipitates may, under some circumstances, obstruct the pores of the CST particles and, hence, interfere with the sorption process. In addition, earlier results from the DWPF recycle stream compatibility testing have shown that leaching occurs from the CST when it is stored at 80 C in a high-pH environment. Evidence was established that some level of components of the CST, such as silica, was leached from the CST. This report describes the results of equilibrium modeling and precipitation studies associated with the overall stability of the waste streams, CST component leaching, and the presence of minor components in the waste streams.
Stochastic analysis of complex reaction networks using binomial moment equations
Barzel, Baruch; Biham, Ofer
2012-09-01
The stochastic analysis of complex reaction networks is a difficult problem because the number of microscopic states in such systems increases exponentially with the number of reactive species. Direct integration of the master equation is thus infeasible and is most often replaced by Monte Carlo simulations. While Monte Carlo simulations are a highly effective tool, equation-based formulations are more amenable to analytical treatment and may provide deeper insight into the dynamics of the network. Here, we present a highly efficient equation-based method for the analysis of stochastic reaction networks. The method is based on the recently introduced binomial moment equations [Barzel and Biham, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.106.150602 106, 150602 (2011)]. The binomial moments are linear combinations of the ordinary moments of the probability distribution function of the population sizes of the interacting species. They capture the essential combinatorics of the reaction processes reflecting their stoichiometric structure. This leads to a simple and transparent form of the equations, and allows a highly efficient and surprisingly simple truncation scheme. Unlike ordinary moment equations, in which the inclusion of high order moments is prohibitively complicated, the binomial moment equations can be easily constructed up to any desired order. The result is a set of equations that enables the stochastic analysis of complex reaction networks under a broad range of conditions. The number of equations is dramatically reduced from the exponential proliferation of the master equation to a polynomial (and often quadratic) dependence on the number of reactive species in the binomial moment equations. The aim of this paper is twofold: to present a complete derivation of the binomial moment equations; to demonstrate the applicability of the moment equations for a representative set of example networks, in which stochastic effects play an important role.
Volume in moment tensor space in terms of distance
Tape, Walter; Tape, Carl
2017-07-01
Suppose that we want to assess the extent to which some large collection of moment tensors is concentrated near a fixed moment tensor m. We are naturally led to consider the distribution of the distances of the moment tensors from m. This distribution, however, can only be judged in conjunction with the distribution of distances from m for randomly chosen moment tensors. In cumulative form, the latter distribution is the same as the fractional volume \\hat{V}(ω ) of the set of all moment tensors that are within distance ω of m. This definition of \\hat{V}(ω ) assumes that a reasonable universe {M} of moment tensors has been specified at the outset and that it includes the original collection as a subset. Our main goal in this article is to derive a formula for \\hat{V}(ω ) when {M} is the set [Λ]_{U} of all moment tensors having a specified eigenvalue triple Λ. We find that \\hat{V}(ω ) depends strongly on Λ, and we illustrate the dependence by plotting the derivative curves \\hat{V}^' }(ω ) for various seismologically relevant Λs. The exotic and unguessable shapes of these curves underscores the futility of interpreting the distribution of distances for the original moment tensors without knowing \\hat{V}(ω ) or \\hat{V}^' }(ω ). The derivation of the formula for \\hat{V}(ω ) relies on a certain ϕ σz coordinate system for [Λ]_{U}, which we treat in detail. Our underlying motivation for the paper is the estimation of uncertainties in moment tensor inversion.
Stochastic analysis of complex reaction networks using binomial moment equations.
Barzel, Baruch; Biham, Ofer
2012-09-01
The stochastic analysis of complex reaction networks is a difficult problem because the number of microscopic states in such systems increases exponentially with the number of reactive species. Direct integration of the master equation is thus infeasible and is most often replaced by Monte Carlo simulations. While Monte Carlo simulations are a highly effective tool, equation-based formulations are more amenable to analytical treatment and may provide deeper insight into the dynamics of the network. Here, we present a highly efficient equation-based method for the analysis of stochastic reaction networks. The method is based on the recently introduced binomial moment equations [Barzel and Biham, Phys. Rev. Lett. 106, 150602 (2011)]. The binomial moments are linear combinations of the ordinary moments of the probability distribution function of the population sizes of the interacting species. They capture the essential combinatorics of the reaction processes reflecting their stoichiometric structure. This leads to a simple and transparent form of the equations, and allows a highly efficient and surprisingly simple truncation scheme. Unlike ordinary moment equations, in which the inclusion of high order moments is prohibitively complicated, the binomial moment equations can be easily constructed up to any desired order. The result is a set of equations that enables the stochastic analysis of complex reaction networks under a broad range of conditions. The number of equations is dramatically reduced from the exponential proliferation of the master equation to a polynomial (and often quadratic) dependence on the number of reactive species in the binomial moment equations. The aim of this paper is twofold: to present a complete derivation of the binomial moment equations; to demonstrate the applicability of the moment equations for a representative set of example networks, in which stochastic effects play an important role.
Impact of AIRS Thermodynamic Profile on Regional Weather Forecast
Chou, Shih-Hung; Zavodsky, Brad; Jedlovee, Gary
2010-01-01
Prudent assimilation of AIRS thermodynamic profiles and quality indicators can improve initial conditions for regional weather models. AIRS-enhanced analysis has warmer and moister PBL. Forecasts with AIRS profiles are generally closer to NAM analyses than CNTL. Assimilation of AIRS leads to an overall QPF improvement in 6-h accumulated precipitation forecasts. Including AIRS profiles in assimilation process enhances the moist instability and produces stronger updrafts and a better precipitation forecast than the CNTL run.
Fantastic Learning Moments and Where to Find Them.
Sheng, Alexander Y; Sullivan, Ryan; Kleber, Kara; Mitchell, Patricia M; Liu, James H; McGreevy, Jolion; McCabe, Kerry; Atema, Annemieke; Schneider, Jeffrey I
2018-01-01
Experiential learning is crucial for the development of all learners. Literature exploring how and where experiential learning happens in the modern clinical learning environment is sparse. We created a novel, web-based educational tool called "Learning Moment" (LM) to foster experiential learning among our learners. We used data captured by LM as a research database to determine where learning experiences were occuring within our emergency department (ED). We hypothesized that these moments would occur more frequently at the physician workstations as opposed to the bedside. We implemented LM at a single ED's medical student clerkship. The platform captured demographic data including the student's intended specialty and year of training as well as "learning moments," defined as logs of learner self-selected learning experiences that included the clinical "pearl," clinical scenario, and location where the "learning moment" occurred. We presented data using descriptive statistics with frequencies and percentages. Locations of learning experiences were stratified by specialty and training level. A total of 323 "learning moments" were logged by 42 registered medical students (29 fourth-year medical students (MS 4) and 13 MS 3 over a six-month period. Over half (52.4%) intended to enter the field of emergency medicine (EM). Of these "learning moments," 266 included optional location data. The most frequently reported location was patient rooms (135 "learning moments", 50.8%). Physician workstations hosted the second most frequent "learning moments" (67, 25.2%). EM-bound students reported 43.7% of "learning moments" happening in patient rooms, followed by workstations (32.8%). On the other hand, non EM-bound students reported that 66.3% of "learning moments" occurred in patient rooms and only 8.4% at workstations (plearning cycle for our learners. In our environment, patient rooms represented the most frequent location of "learning moments," followed by physician
Characterization and Modeling of a Control Moment Gyroscope
2015-03-26
Characterization and Modeling of a Control Moment Gyroscope THESIS 2d Lt, Dylan Penn, B.S. AFIT-ENY-MS-15-M-235 DEPARTMENT OF THE AIR FORCE AIR...copyright protection in the United States. AFIT-ENY-MS-15-M-235 CHARACTERIZATION AND MODELING OF A CONTROL MOMENT GYROSCOPE THESIS Presented to the...ENY-MS-15-M-235 CHARACTERIZATION AND MODELING OF A CONTROL MOMENT GYROSCOPE THESIS 2d Lt, Dylan Penn, B.S., B.S. Mechanical Engineering Committee
The moment sum-rules for ionic liquids at criticality
Fantoni, Riccardo
2017-07-01
We discuss the first three well known moment charge-charge sum-rules for a general ionic liquid. For the special symmetric case of the Restricted Primitive Model, Das, Kim, and Fisher (2011) has recently discovered, through Monte Carlo simulations, that the Stillinger-Lovett or second-moment sum-rule fails at criticality. We critically discuss a possible explanation for this unexpected behavior. On the other hand the fourth-moment sum-rule turns out to be able to account for the results of the simulations at criticality.
Undrained Response of Bucket Foundations to Moment Loading
DEFF Research Database (Denmark)
Barari, Amin; Ibsen, Lars Bo
2012-01-01
Bucket foundation as a large cylindrical structure that is open at the base and closed at the top, is recently being used within the offshore wind turbines projects. The bearing capacity of bucket foundations to moment loading in undrained soil is of interest particularly to the offshore...... geotechnical engineers. This paper presents the experimental and numerical results of moment loading on small scale models of bucket foundations installed on Yoldia clay. The moment loading is experienced via the horizontal forces applied to features on a tower installed on bucket foundations. Different arm...
Estimation of moments of inertia of airplanes from design data
Kirschbaum, H W
1936-01-01
A method of determining the moments of inertia of an airplane from design data pertaining to the weights and locations of the component parts is described. The computations required to ascertain the center-of-gravity position are incorporated with the calculations of moments of inertia. A complete set of data and calculations for a modern airplane is given to illustrate the procedure. From a comparison between calculated values and measured values it is believed that the moments of inertia can be estimated within 10 percent by the use of this method.
A image watermark resisting geometrical attacks based on quaternion moments
Wu, Ge
2017-08-01
This paper, proposes a method that by generating a quaternion moments, which will work as the watermark by multiply the quaternion orthogonal moments. Firstly, quaternion orthogonal moments matrix is gotten from source image and watermarking image separately. Secondly extract N dimension matrix of two matrixes, multiply two matrixes to get a new matrix as the copyright information. Finally the matrix is sent to the copyright center. The watermark can be detected effectively, and it is robust against RST attacking such as rotating attack, cropping and scaling attack.
Higher moments of weighted integrals of non-Gaussian fields
DEFF Research Database (Denmark)
Mohr, Gunnar
1999-01-01
In general, the exact probability distribution of a definite integral of a given non-Gaussian random field is not known. Some information about this unknown distribution can be obtained from the 3rd and 4th moment of the integral. Approximations to these moments can be calculated by discretizing...... engineering mechanics, 1996) based on these ideas is discussed and further developed and used in a computer program which produces fairly accurate approximations to the mentioned moments with no restrictions put on the weight function applied to the field and the correlation function of the field...
Directory of Open Access Journals (Sweden)
Hamidreza Farhoudi
2016-12-01
Full Text Available This study predicts the frictional moments at the head-cup interface and frictional torques and bending moments acting on the head-neck interface of a modular total hip replacement across a range of activities of daily living. The predicted moment and torque profiles are based on the kinematics of four patients and the implant characteristics of a metal-on-metal implant. Depending on the body weight and type of activity, the moments and torques had significant variations in both magnitude and direction over the activity cycles. For the nine investigated activities, the maximum magnitude of the frictional moment ranged from 2.6 to 7.1 Nm. The maximum magnitude of the torque acting on the head-neck interface ranged from 2.3 to 5.7 Nm. The bending moment acting on the head-neck interface varied from 7 to 21.6 Nm. One-leg-standing had the widest range of frictional torque on the head-neck interface (11 Nm while normal walking had the smallest range (6.1 Nm. The widest range, together with the maximum magnitude of torque, bending moment, and frictional moment, occurred during one-leg-standing of the lightest patient. Most of the simulated activities resulted in frictional torques that were near the previously reported oxide layer depassivation threshold torque. The predicted bending moments were also found at a level believed to contribute to the oxide layer depassivation. The calculated magnitudes and directions of the moments, applied directly to the head-neck taper junction, provide realistic mechanical loading data for in vitro and computational studies on the mechanical behaviour and multi-axial fretting at the head-neck interface.
Moments and power generated by the horse (Equus caballus) hind limb during jumping.
Dutto, Darren J; Hoyt, Donald F; Clayton, Hilary M; Cogger, Edward A; Wickler, Steven J
2004-02-01
The ability to jump over an obstacle depends upon the generation of work across the joints of the propelling limb(s). The total work generated by one hind limb of a horse and the contribution to the total work by four joints of the hind limb were determined for a jump. It was hypothesized that the hip and ankle joints would have extensor moments performing positive work, while the knee would have a flexor moment and perform negative work during the jump. Ground reaction forces and sagittal plane kinematics were simultaneously recorded during each jumping trial. Joint moment, power and work were determined for the metatarsophalangeal (MP), tarsal (ankle), tibiofemoral (knee) and coxofemoral (hip) joints. The hip, knee and ankle all flexed and then extended and the MP extended and then flexed during ground contact. Consistent with our hypothesis, large extensor moments were observed at the hip and ankle joints and large flexor moments at the knee and MP joints throughout ground contact of the hind limb. Peak moments tended to occur earlier in stance in the proximal joints but peak power generation of the hind limb joints occurred at similar times except for the MP joint, with the hip and ankle peaking first followed by the MP joint. During the first portion of ground contact (approximately 40%), the net result of the joint powers was the absorption of power. During the remainder of the contact period, the hind limb generated power. This pattern of power absorption followed by power generation paralleled the power profiles of the hip, ankle and MP joints. The total work performed by one hind limb was 0.71 J kg(-1). Surprisingly, the knee produced 85% of the work (0.60 J kg(-1)) done by the hind limb, and the positive work performed by the knee occurred during the first 40% of the take-off. There is little net work generated by the other three joints over the entire take-off. Velocity of the tuber coxae (a landmark on the pelvis of the animal) was negative (downward
On the Computation of the Moments of a Polygon, with some Applications
Soerjadi, R.
1968-01-01
A general formula for moments of a polygon is derived. The concept of 'moment' is a generalization of the statical, inertial and centrifugal moment respectively of a polygon, which as such are special moments of first and second order. Moments of higher order, however, also have applications in
Miniature, Variable-Speed Control Moment Gyroscope Project
National Aeronautics and Space Administration — The overall goal of this project is to design, develop, demonstrate, and deliver a miniature, variable speed control moment gyroscope (MVS CMG) for use on small...
DETERMINATI>N OF MOMENTS OF INERTIA: A FACILITIES STUDY,
which can be accommodated by the facility. It is concluded that the amount of manual manipulacion required for moment of inertia 4easurements can be reduced by improving che usefulness of present equipment. (Author)
A Bimorph Moment/Force Actuator for Dynamic Testing
Directory of Open Access Journals (Sweden)
Hou Xiaoyan
2009-09-01
Full Text Available This paper focuses on a novel bimorph actuator which can produce pure moment or pure force to structures under testing. Due to its unique construction, this actuator is only sensitive to one translational and one rotational degree of freedom (DOF, which can be further decoupled from each other through controlling the phase of the excitation voltage supplied to the actuator. To correlate the input electrical voltage with the output moment (or force, angular velocity, linear velocity, rotational (or translational conversion functions are defined and then numerically determined. Compared with conventional twin-shaker setup to generate moment, the bimorph actuator is simple, compact, light-weight, effective and cheap. When generating moment, the usually-existing unwanted force excitation is avoided. The working frequency range of the actuator is much wider and the loading effect is greatly reduced.
A Hybrid Joint Moment Ratio Test for Financial Time Series
Groenendijk, Patrick A.; Lucas, André; Vries, de Casper G.
1998-01-01
We advocate the use of absolute moment ratio statistics in conjunctionwith standard variance ratio statistics in order to disentangle lineardependence, non-linear dependence, and leptokurtosis in financial timeseries. Both statistics are computed for multiple return horizonssimultaneously, and the
VOYAGER 1 SATURN PLASMA DERIVED ION MOMENTS 96 SEC
National Aeronautics and Space Administration — THIS DATA SET CONTAINS ESTIMATES OF THE ION MOMENT DENSITY IN THE PLS VOLTAGE RANGE (10-5950 EV/Q) AT SATURN DURING THE VOYAGER 1 ENCOUNTER. RIGID COROTATION IS...
VOYAGER 2 JUPITER PLASMA DERIVED ELECTRON MOMENTS 96 SEC
National Aeronautics and Space Administration — THIS DATA SET CONTAINS THE DERIVED VALUES FOR THE ELECTRON MOMENT DENSITY AND TEMPERATURE AT JUPITER IN THE PLS ENERGY RANGE (10-5950 EV) DURING THE VOYAGER 2...
VOYAGER 2 SATURN PLASMA DERIVED ION MOMENTS 96 SEC
National Aeronautics and Space Administration — THIS DATA SET CONTAINS ESTIMATES OF THE ION MOMENT DENSITY IN THE PLS VOLTAGE RANGE (10-5950 EV/Q) AT SATURN DURING THE VOYAGER 2 ENCOUNTER. RIGID COROTATION IS...
Momentous discoveries on Mars: science outside MEP pathways
Easter, R. W.; Delitsky, M. I.; Lamassoure, E.; Marshall, M. F.; Matthews, J. B.; Palkovic, L. A.; Wilson, T. J.
2003-01-01
The Mars Outpost Team seeks further input from the Mars community about other possible momentous discoveries that could be made, as well as ways to respond to them (types of missions, instruments, spacecraft-orbiters, landers, rovers, airplanes, etc.).
CONCENTRATION OF Pu USING AN IODATE PRECIPITATE
Fries, B.A.
1960-02-23
A method is given for separating plutonium from lanthanum in a lanthanum fluoride carrier precipitation process for the recovery of plutonium values from an aqueous solution. The carrier precipitation process includes the steps of forming a lanthanum fluoride precipi- . tate, thereby carrying plutonium out of solution, metathesizing the fluoride precipitate to a hydroxide precipitate, and then dissolving the hydroxide precipitate in nitric acid. In accordance with the invention, the nitric acid solution, which contains plutonium and lanthanum, is made 0.05 to 0.15 molar in potassium iodate. thereby precipitating plutonium as plutonous iodate and the plutonous iodate is separated from the lanthanum- containing supernatant solution.
Application of the Empirical Thresholds of Precipitation to the Debris Flows in Mexico
Cardoso-Landa, G.
2013-05-01
The debris flows are particularly dangerous for the life and the properties due to its high speeds and great destructive force, destroying houses, ways, bridges, trees and cultures, currents and ecosystems throughout its trajectory. The extraordinary precipitation events are one of the predominant physical processes that produce the genesis of the debris flows. The empirical thresholds of precipitation are based on the historical analyses of the occurrence relation precipitation/debris flow, for example statistical analyses. At the present time a limited number of this type of empirical thresholds exists and have been used different diagrams to represent them, depending on the combinations of precipitation parameters more commonly used: antecedent precipitation, duration, accumulated intensity and rain, and the most commons are that obtained by Caine and Aleotti. An analytical presentation of the concept of threshold of precipitation of a debris flow was recently introduced by Iritanno et al. (1998), who introduced the called function of mobilization Y(t), indirectly describing all the factors that contribute to trigger a process of landslides and that is dependent, in every moment of time t, the amount of water infiltrate on the ground before the time t. In the full article was applied the Iritanno's function of mobilization to the records of precipitation that produced the debris flows in the north of Puebla State, in the country of México, obtaining relationships intensity of rain-duration for these debris flows are greater from 3.43 to 2.1 times over empirical thresholds of precipitation generators of debris flows proposed by Caine and Aleotti in other regions of the world. .Intensity of precipitation for the debris flows in Mexicot;
Deterministic Dynamical Bounds on Moments of Nonstationary Stochastic Processes
Carrette, Pierre
1998-01-01
In this contribution, we deal with the deterministic dominance of the probability moments of stochastic processes. More precisely, given a positive stochastic process, we propose to dominate its probability moment sequence by the trajectory of appropriate lower and upper dominating deterministic processes. The analysis of the behavior of the original stochastic process is then transferred to the stability analysis of the deterministic dominating processes. The result is applied to a nonstatio...
Rotation invariants of vector fields from orthogonal moments
Czech Academy of Sciences Publication Activity Database
Yang, B.; Kostková, Jitka; Flusser, Jan; Suk, Tomáš; Bujack, R.
2018-01-01
Roč. 74, č. 1 (2018), s. 110-121 ISSN 0031-3203 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Vector field * Total rotation * Invariants * Gaussian–Hermite moments * Zernike moments * Numerical stability Subject RIV: JD - Computer Applications, Robotics Impact factor: 4.582, year: 2016 http:// library .utia.cas.cz/separaty/2017/ZOI/flusser-0478329.pdf
Heeling Moment Acting on a River Cruiser in Manoeuvring Motion
Directory of Open Access Journals (Sweden)
Tabaczek Tomasz
2016-01-01
Full Text Available By using fully theoretical method the heeling moment due to centrifugal forces has been determined for a small river cruiser in turning manoeuvre. The authors applied CFD software for determination of hull hydrodynamic forces, and open water characteristics of ducted propeller for estimation of thrust of rudder-propellers. Numerical integration of equations of 3DOF motion was used for prediction of ship trajectory and time histories of velocities, forces and heeling moment.
Fourth moments and the dynamics of spherical systems
Energy Technology Data Exchange (ETDEWEB)
Merrifield, M.R.; Kent, S.M. (Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA))
1990-05-01
An investigation of the fourth moment of velocity data from the globular cluster Omega Cen demonstrates that useful constraints can be obtained from a dataset of only 300 velocities. The fourth moment of this sample is shown to be inconsistent with an isotropic velocity distribution and suggests that the orbits become predominantly radial at large radii. A more complete analysis of this and other systems awaits larger and more homogeneous samples. 18 refs.
Leading Quenching Effects in the Proton Magnetic Moment
Energy Technology Data Exchange (ETDEWEB)
R.D. Young; D.B Leinweber; Anthony Thomas
2004-06-01
We present the first investigation of the extrapolation of quenched nucleon magnetic moments in quenched chiral effective field theory. We utilize established techniques in finite-range regularization and compare with standard dimensional regularization methods. Finite-volume corrections to the relevant loop integrals are also addressed. Finally, the contributions of dynamical sea quarks to the proton moment are estimated using a recently discovered phenomenological link between quenched and physical QCD.
A note on the anomalous magnetic moment of the muon
Palle, Davor
2016-01-01
The anomalous magnetic moment of the muon is an important observable that tests radiative corrections of all three observed local gauge forces: electromagnetic, weak and strong interactions. High precision measurements reveal some discrepancy with the most accurate theoretical evaluations of the anomalous magnetic moment. We show in this note that the UV finite theory cannot resolve this discrepancy. We believe that more reliable estimate of the nonperturbative hadronic contribution and the new measurements can resolve the problem.
Torsional Moment Measurement on Bucket Wheel Shaft of Giant Machine
Directory of Open Access Journals (Sweden)
Jiří FRIES
2011-06-01
Full Text Available Bucket wheel loading at the present time (torsional moment on wheel shaft, peripheral cutting force is determined from electromotor incoming power or reaction force measured on gearbox hinge. Both methods together are weighted by steel construction absorption of driving units and by inertial forces of motor rotating parts. In the article is described direct method of the torsional moment measurement, which eliminates mentioned unfavourable impacts except absorption of steel construction of bucket wheel itself.
Higher moments of Banach space valued random variables
Janson, Svante
2015-01-01
The authors define the k:th moment of a Banach space valued random variable as the expectation of its k:th tensor power; thus the moment (if it exists) is an element of a tensor power of the original Banach space. The authors study both the projective and injective tensor products, and their relation. Moreover, in order to be general and flexible, we study three different types of expectations: Bochner integrals, Pettis integrals and Dunford integrals.
Searching for the corner seismic moment in worldwide data
Energy Technology Data Exchange (ETDEWEB)
Felgueiras, Miguel; Santos, Rui; Martins, João Paulo [CEAUL Lisbon and ESTG, Polytechnic Institute of Leiria (Portugal)
2015-12-31
In this paper the existence of the corner frequency value for the seismic moment distribution is investigated, analysing worldwide data. Pareto based distributions, usually considered as the most suitable to this type of data, are fitted to the most recent data, available in a global earthquake catalog. Despite the undeniable finite nature of the seismic moment data, we conclude that no corner frequency can be established considering the available data set.
Global Precipitation Measurement (GPM) Mission: Overview and Status
Hou, Arthur Y.
2012-01-01
The Global Precipitation Measurement (GPM) Mission is an international satellite mission specifically designed to unify and advance precipitation measurements from a constellation of research and operational microwave sensors. NASA and JAXA will deploy a Core Observatory in 2014 to serve as a reference satellite to unify precipitation measurements from the constellation of sensors. The GPM Core Observatory will carry a Ku/Ka-band Dual-frequency Precipitation Radar (DPR) and a conical-scanning multi-channel (10-183 GHz) GPM Microwave Radiometer (GMI). The DPR will be the first dual-frequency radar in space to provide not only measurements of 3-D precipitation structures but also quantitative information on microphysical properties of precipitating particles. The DPR and GMI measurements will together provide a database that relates vertical hydrometeor profiles to multi-frequency microwave radiances over a variety of environmental conditions across the globe. This combined database will be used as a common transfer standard for improving the accuracy and consistency of precipitation retrievals from all constellation radiometers. For global coverage, GPM relies on existing satellite programs and new mission opportunities from a consortium of partners through bilateral agreements with either NASA or JAXA. Each constellation member may have its unique scientific or operational objectives but contributes microwave observations to GPM for the generation and dissemination of unified global precipitation data products. In addition to the DPR and GMI on the Core Observatory, the baseline GPM constellation consists of the following sensors: (1) Special Sensor Microwave Imager/Sounder (SSMIS) instruments on the U.S. Defense Meteorological Satellite Program (DMSP) satellites, (2) the Advanced Microwave Scanning Radiometer-2 (AMSR-2) on the GCOM-W1 satellite of JAXA, (3) the Multi-Frequency Microwave Scanning Radiometer (MADRAS) and the multi-channel microwave humidity sounder
What predicts the first peak of the knee adduction moment?
Schmitz, Anne; Noehren, Brian
2014-01-01
Introduction The first peak of the knee adduction moment curve during walking has been shown to be a good clinical surrogate measure of medial tibiofemoral joint loading and osteoarthritis. Defining the relative contributions of the variables that dictate the knee adduction moment, such as center of mass, center of pressure, vertical ground reaction force, and knee adduction angle (i.e. lower limb alignment), has not been formally investigated within the same cohort of individuals. Purpose Therefore, the goal of this study was to determine which of these variables is the biggest determinant of the first peak of knee adduction moment curve. Methods Instrumented gait analysis was collected for 30 individuals. Variables significantly correlated with the peak knee adduction moment were input into a stepwise multi-variable linear regression model. Results The knee adduction angle predicted 58% of the variance in the first peak knee adduction moment and the vertical ground reaction force magnitude predicted the second most variance (20%). Conclusions The most effective way to modify the peak knee adduction moment may be to change the knee adduction angle (e.g. offloader brace), followed by changing the vertical magnitude of the ground reaction force (e.g. cane use). PMID:25127390
Instrument for measuring moment of inertia with high precision
Zheng, Yongjun; Lin, Min; Guo, Bin
2010-08-01
Accurate calculation of the moment of inertia of an irregular body is made difficult by the large number of quantities. A popular method is to use a trifilar suspension system to measure the period of oscillation of the body in the horizontal plane. In this paper, an instrument for measuring the moment of inertia based on trifilar pendulum is designed; some sources of error are discussed; three metal disks with known moments of inertia are used to calibrate the instrument, the other metal disks with known moments of inertia are used to test the accuracy of the instrument. The results are consistent when compared with calculated moment of inertia of the metal disks. In addition, the instrument could be used to measure the moment of inertia of other irregular objects. The period of oscillation is acquired by the capture mode of MSP430 microprocessor, the mass is obtained by the Electronic Balance and the data is transferred to the MSP430 via serial port.
Effect of reverse shoulder design philosophy on muscle moment arms.
Hamilton, Matthew A; Diep, Phong; Roche, Chris; Flurin, Pierre Henri; Wright, Thomas W; Zuckerman, Joseph D; Routman, Howard
2015-04-01
This study analyzes the muscle moment arms of three different reverse shoulder design philosophies using a previously published method. Digital bone models of the shoulder were imported into a 3D modeling software and markers placed for the origin and insertion of relevant muscles. The anatomic model was used as a baseline for moment arm calculations. Subsequently, three different reverse shoulder designs were virtually implanted and moment arms were analyzed in abduction and external rotation. The results indicate that the lateral offset between the joint center and the axis of the humerus specific to one reverse shoulder design increased the external rotation moment arms of the posterior deltoid relative to the other reverse shoulder designs. The other muscles analyzed demonstrated differences in the moment arms, but none of the differences reached statistical significance. This study demonstrated how the combination of variables making up different reverse shoulder designs can affect the moment arms of the muscles in different and statistically significant ways. The role of humeral offset in reverse shoulder design has not been previously reported and could have an impact on external rotation and stability achieved post-operatively. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
A new online database of nuclear electromagnetic moments
Mertzimekis, Theo J.
2017-09-01
Nuclear electromagnetic (EM) moments, i.e., the magnetic dipole and the electric quadrupole moments, provide important information of nuclear structure. As in other types of experimental data available to the community, measurements of nuclear EM moments have been organized systematically in compilations since the dawn of nuclear science. However, the wealth of recent moments measurements with radioactive beams, as well as earlier existing measurements, lack an online, easy-to-access, systematically organized presence to disseminate information to researchers. In addition, available printed compilations suffer a rather long life cycle, being left behind experimental measurements published in journals or elsewhere. A new, online database (http://magneticmoments.info) focusing on nuclear EM moments has been recently developed to disseminate experimental data to the community. The database includes non-evaluated experimental data of nuclear EM moments, giving strong emphasis on frequent updates (life cycle is 3 months) and direct connection to the sources via DOI and NSR hyperlinks. It has been recently integrated in IAEA LiveChart [1], but can also be found as a standalone webapp [2]. A detailed review of the database features, as well as plans for further development and expansion in the near future is discussed.
Electric-field control of magnetic moment in Pd
Obinata, Aya; Hibino, Yuki; Hayakawa, Daichi; Koyama, Tomohiro; Miwa, Kazumoto; Ono, Shimpei; Chiba, Daichi
2015-01-01
Several magnetic properties have recently become tunable with an applied electric field. Particularly, electrically controlled magnetic phase transitions and/or magnetic moments have attracted attention because they are the most fundamental parameters in ferromagnetic materials. In this study, we showed that an electric field can be used to control the magnetic moment in films made of Pd, usually a non-magnetic element. Pd ultra-thin films were deposited on ferromagnetic Pt/Co layers. In the Pd layer, a ferromagnetically ordered magnetic moment was induced by the ferromagnetic proximity effect. By applying an electric field to the ferromagnetic surface of this Pd layer, a clear change was observed in the magnetic moment, which was measured directly using a superconducting quantum interference device magnetometer. The results indicate that magnetic moments extrinsically induced in non-magnetic elements by the proximity effect, as well as an intrinsically induced magnetic moments in ferromagnetic elements, as reported previously, are electrically tunable. The results of this study suggest a new avenue for answering the fundamental question of “can an electric field make naturally non-magnetic materials ferromagnetic?” PMID:26391306
Rowing and the same-sum problem have their moments
Barrow, John D.
2010-07-01
We consider the optimal positioning of an even number of identical crew members in a coxless racing boat so as to avoid the presence of a sideways wiggle as the boat is propelled forward through the water. We show that the traditional (alternate port and starboard) positioning always possesses an oscillating nonzero transverse moment and associated wiggling motion and that the problem of finding the zero-moment positions is related to a special case of the subset sum problem. We find the one (known) zero-moment rig for a racing Four and show that there are four possible such rigs for a racing Eight, of which only two are known. We show that only balanced boats with crew numbers that are divisible by four can have the zero-moment property and give the 29 zero-moment solutions for racing Twelves, which have zero transverse moments. Some aspects of unbalanced boats in which the numbers of port and starboard oars are unequal are also discussed.
Protein purification by affinity precipitation.
Hilbrig, Frank; Freitag, Ruth
2003-06-25
Developing the most efficient strategy for the purification of a (recombinant) protein especially at large scale remains a challenge. A typical problem of the downstream process of mammalian cell products is, for instance, the early capture of the highly diluted product from the complex process stream. Affinity precipitation has been suggested in this context. The technique is known for over 20 years, but has recently received more attention due to the development of new materials for its implementation, but also because it seems ideally suited to specific product capture at large scale. The present review gives a comprehensive overview over this technique. Besides an introduction to the basic principle and a brief summary of the historical development, the main focus is on the current state-of-art of the technique, the available materials, important recent applications, as well as process design strategies and operating procedures. Special consideration is given to affinity precipitation for product recovery at large scale.
Precipitation patterns during channel flow
Jamtveit, B.; Hawkins, C.; Benning, L. G.; Meier, D.; Hammer, O.; Angheluta, L.
2013-12-01
Mineral precipitation during channelized fluid flow is widespread in a wide variety of geological systems. It is also a common and costly phenomenon in many industrial processes that involve fluid flow in pipelines. It is often referred to as scale formation and encountered in a large number of industries, including paper production, chemical manufacturing, cement operations, food processing, as well as non-renewable (i.e. oil and gas) and renewable (i.e. geothermal) energy production. We have studied the incipient stages of growth of amorphous silica on steel plates emplaced into the central areas of the ca. 1 meter in diameter sized pipelines used at the hydrothermal power plant at Hellisheidi, Iceland (with a capacity of ca 300 MW electricity and 100 MW hot water). Silica precipitation takes place over a period of ca. 2 months at approximately 120°C and a flow rate around 1 m/s. The growth produces asymmetric ca. 1mm high dendritic structures ';leaning' towards the incoming fluid flow. A novel phase-field model combined with the lattice Boltzmann method is introduced to study how the growth morphologies vary under different hydrodynamic conditions, including non-laminar systems with turbulent mixing. The model accurately predicts the observed morphologies and is directly relevant for understanding the more general problem of precipitation influenced by turbulent mixing during flow in channels with rough walls and even for porous flow. Reference: Hawkins, C., Angheluta, L., Hammer, Ø., and Jamtveit, B., Precipitation dendrites in channel flow. Europhysics Letters, 102, 54001
Choi, Y.; Shin, D. B.; Joh, M.
2015-12-01
Numerical simulations of precipitation depend to a large degree on the assumed cloud microphysics schemes representing the formation, growth and fallout of cloud droplets and ice crystals. Recent studies show that assumed cloud microphysics play a major role not only in forecasting precipitation, especially in cases of extreme precipitation events, but also in the quality of the passive microwave rainfall estimation. Evaluations of the various Weather Research Forecasting (WRF) model microphysics schemes in this study are based on a method that was originally developed to construct the a-priori databases of precipitation profiles and associated brightness temperatures (TBs) for precipitation retrievals. This methodology generates three-dimensional (3D) precipitation fields by matching the GPM dual frequency radar (DPR) reflectivity profiles with those calculated from cloud resolving model (CRM)-derived hydrometeor profiles. The method eventually provides 3D simulated precipitation fields over the DPR scan swaths. That is, atmospheric and hydrometeor profiles can be generated at each DPR pixel based on CRM and DPR reflectivity profiles. The generated raining systems over DPR observation fields can be applied to any radiometers that are unaccompanied with a radar for microwave radiative calculation with consideration of each sensor's channel and field of view. Assessment of the WRF model microphysics schemes for several typhoon cases in terms of emission and scattering signals of GMI will be discussed.
Characteristics of summer and winter precipitation over northern China
Wen, Guang; Xiao, Hui; Yang, Huiling; Bi, Yongheng; Xu, Wenjing
2017-11-01
In this paper, the statistical properties of summer and winter precipitation over the northern China plain are investigated by using a two-dimensional video disdrometer (2DVD) and a micro-rain radar (MRR). The properties of summer precipitation presented herein are bulk properties (radar reflectivity, reflectivity-weighted fall velocity, liquid water content, and rainfall rate), raindrop fall velocity, axis ratio, and particle size distribution. Well correlations can be found among the diurnal cycles of radar reflectivity, liquid water content, and rainfall rate, whereas reflectivity-weighted fall velocity is poorly related to other bulk properties. The vertical profiles exhibit that radar reflectivity for stratiform rain is increasing with the altitude decreasing, in contrast, liquid water content and rainfall rate are reducing during the falling. These facts are useful for the radar-based rainfall rate retrieval algorithm. Axis ratio measurements are, for the first time, obtained and analyzed in northern China, which are particularly important for improving microphysical scheme in the climate models. In the constraint gamma model, the μ - Λ relation is adapted to the particle size distribution of stratiform rain, while the normalized gamma distributions for convective rain are separated to maritime-like and continental categories following the orientations and mechanisms of the storms. A new bulk-property-based algorithm is developed for the classification of convective and stratiform precipitation. For winter precipitation, radar reflectivity and snowfall rate for aggregates are calculated from the disdrometer data. The relationship of radar reflectivity and snowfall rate is obtained and validated with MRR data. The characteristics of summer and winter precipitation will be used to improve the microphysical scheme and evaluate the representation of precipitation in the climate models.
Predictibility in Nowcasting of Precipitation
Zawadzki, I.; Sourcel, M.; Berenguer, M.
2009-05-01
Present short term precipitation forecasting is based on two methods: Lagrangian persistence (nowcasting) and numerical weather prediction (NWP). An improvement over these methods is obtained by the combination of the two. The obvious shortcoming of nowcasting is its severe limitation in capturing new development or dissipation of precipitation. NWP has the ability to predict both but very imprecisely. An attempt to correct model errors by post-processing leads to some improvement in the skill of NWP, but the improvement, although significative, is not very impressive. The goal of our effort is to take a step back and to describe, in a quantitative manner, a) the nature of the uncertainties affecting Lagrangian persistence and NWP forecasts, as well as to determineb) the physical causes of the uncertainties. We quantify the uncertainties in short term forecasting due to limitation of nowcasting algorithms and NWP to capture correctly some of the physical phenomena that determine the predictability of precipitation. The first factor considered is the diurnal cycle that appears as the one physically determined factors that limit the precision of short term prediction. We study the cycle in radar mosaics over US and compare this to nowcasts and model outputs. The seasonal and geographical dependence of the diurnal cycle is quantitatively evaluated.
European climate change experiments on precipitation change
DEFF Research Database (Denmark)
Beier, Claus
Presentation of European activities and networks related to experiments and databases within precipitation change......Presentation of European activities and networks related to experiments and databases within precipitation change...
River Forecasting Center Quantitative Precipitation Estimate Archive
U.S. Geological Survey, Department of the Interior — Radar indicated-rain gage verified and corrected hourly precipitation estimate on a corrected ~4km HRAP grid. This archive contains hourly estimates of precipitation...
U.S. 15 Minute Precipitation Data
National Oceanic and Atmospheric Administration, Department of Commerce — U.S. 15 Minute Precipitation Data is digital data set DSI-3260, archived at the National Climatic Data Center (NCDC). This is precipitation data. The primary source...
Amazon River Basin Precipitation, 1972-1992
National Aeronautics and Space Administration — ABSTRACT: The precipitation data is 0.2 degree gridded monthly precipitation data based upon monthly rain data from Peru and Bolivia and daily rain data from Brazil....
Amazon River Basin Precipitation, 1972-1992
National Aeronautics and Space Administration — The precipitation data is 0.2 degree gridded monthly precipitation data based upon monthly rain data from Peru and Bolivia and daily rain data from Brazil. The...
CODA-DERIVED SOURCE SPECTRA, MOMENT MAGNITUDES, AND ENERGY-MOMENT SCALING IN THE WESTERN ALPS
Energy Technology Data Exchange (ETDEWEB)
Morasca, P; Mayeda, K; Malagnini, L; Walter, W
2004-02-03
A stable estimate of the earthquake source spectra in the western Alps is obtained using an empirical method based on coda envelope amplitude measurements described by Mayeda et al. (2003) for events ranging between M{sub W} {approx} 1.0 to {approx}5.0. We calibrated path corrections for consecutive narrow frequency bands ranging between 0.2 and 25.0-Hz using a simple 1-D model for 5 three-component stations of the Regional Seismic network of Northwestern Italy (RSNI). The 1-D assumption performs well, even though the region is characterized by a complex structural setting involving strong lateral variations in the Moho depth. For frequencies less than 1.0-Hz, we tied our dimensionless, distance-corrected coda amplitudes to an absolute scale in units of dyne-cm by using independent moment magnitudes from long-period waveform modeling for 3 moderate magnitude events in the region. For the higher frequencies, we used small events as empirical Green's functions, with corner frequencies above 25.0-Hz. For each station, the procedure yields frequency-dependent corrections that account for site effects, including those related to f{sub max}, as well as those related to S-to-coda transfer function effects. After the calibration was completed, the corrections were applied to the entire data-set composed of 957 events. Our findings using the coda-derived source spectra are summarized as follows: (1) We derived stable estimates of seismic moment, M{sub 0}, (and hence M{sub W}) as well as radiated S-wave energy, (E{sub S}), from waveforms recorded by as few as one station, for events that were too small to be waveform modeled (i.e., events less than M{sub W} {approx}3.5); (2) The source spectra were used to derive an equivalent local magnitude, M{sub L(coda)}, that is in excellent agreement with the network averaged values using direct S-waves; (3) Scaled energy, {tilde e} = E{sub R}/M{sub 0}, where E{sub R}, the radiated seismic energy, is comparable to results from
Global Precipitation Measurement (GPM) Mission: NASA Precipitation Processing System (PPS)
Stocker, Erich Franz
2008-01-01
NASA is contributing the precipitation measurement data system PPS to support the GPM mission. PPS will distribute all GPM data products including NASA s GMI data products freely and quickly. PPS is implementing no system mechanisms for restricting access to GPM data. PPS is implementing no system mechanisms for charging for GPM data products. PPS will provide a number of geographical and parameter subsetting features available to its users. The first implementation of PPS (called PPS--) will assume processing of TRMM data effective 1 June 2008. TRMM realtime data will be available via PPS- to all users requesting access
Climate change projections for precipitation in Portugal
Andrade, C.; Santos, J. A.
2013-10-01
The strong irregularity of precipitation in Portugal, which may e.g. trigger severe/extreme droughts and floods, results in a high vulnerability of the country to precipitation inter-annual variability and to its extremes. Furthermore, dryer future climates are projected for Portugal, though there has also been some growing evidence for a strengthening of precipitation extremes. Due to the central role played byprecipitation on many socio-economic sectors and environmental systems, regional climate change assessments for precipitation in Portugal are necessary. This study is focused on analyzing climate change projections for seasonal (3-month) precipitation totals and their corresponding extremes over mainland Portugal. Taking into account the strong seasonality of the precipitation regimes in Portugal, winter (DJF) and summer (JJA) are considered separately. Precipitation datasets generated by a 16-member ensemble of regional climate model experiments from the ENSEMBLES project are used. Percentile-based indices of precipitation are computed and analyzed for a recent past period (1961-2000) and for a near future period (2041-2070). Results for the R5p, R50p and R95p indices highlight significant projected changes in precipitation, with a clear distinction between northwestern Portugal and the rest of the country in both seasons. Overall, precipitation is projected to decrease in both seasons, particularly over northwestern Portugal in winter, despite some significant regional differences. Although precipitation is projected to decrease in most cases, extremely high seasonal precipitations (above the 95th percentile)areexpected to increase in winter.
Acid Precipitation and the Forest Ecosystem
Dochinger, Leon S.; Seliga, Thomas A.
1975-01-01
The First International Symposium on Acid Precipitation and the Forest Ecosystem dealt with the potential magnitude of the global effects of acid precipitation on aquatic ecosystems, forest soils, and forest vegetation. The problem is discussed in the light of atmospheric chemistry, transport, and precipitation. (Author/BT)
The weak acid nature of precipitation
John O. Frohliger; Robert L. Kane
1976-01-01
Recent measurements of the pH of precipitation leave no doubt that rainfall is acidic. Evidence will be presented that precipitation is a weak acid system. The results of this research indicate the need to establish standard sampling procedures to provide uniform sampling of precipitation
Soil water dynamics during precipitation in genetic horizons of Retisol
Zaleski, Tomasz; Klimek, Mariusz; Kajdas, Bartłomiej
2017-04-01
Retisols derived from silty deposits dominate in the soil cover of the Carpathian Foothills. The hydrophysical properties of these are determined by the grain-size distribution of the parent material and the soil's "primary" properties shaped in the deposition process. The other contributing factors are the soil-forming processes, such as lessivage (leaching of clay particles), and the morphogenetic processes that presently shape the relief. These factors are responsible for the "secondary" differentiation of hydrophysical properties across the soil profile. Both the primary and secondary hydrophysical properties of soils (the rates of water retention, filtration and infiltration, and the moisture distribution over the soil profile) determine their ability to take in rainfall, the amount of rainwater taken in, and the ways of its redistribution. The aims of the study, carried out during 2015, were to investigate the dynamics of soil moisture in genetic horizons of Retisol derived from silty deposits and to recognize how fast and how deep water from precipitation gets into soil horizons. Data of soil moisture were measured using 5TM moisture and temperature sensor and collected by logger Em50 (Decagon Devices USA). Data were captured every 10 minutes from 6 sensors at depths: - 10 cm, 20 cm, 40 cm, 60 cm and 80 cm. Precipitation data come from meteorological station situated 50 m away from the soil profile. Two zones differing in the type of water regime were distinguished in Retisol: an upper zone comprising humic and eluvial horizons, and a lower zone consisting of illuvial and parent material horizons. The upper zone shows smaller retention of water available for plants, and relatively wide fluctuations in moisture content, compared to the lower zone. The lower zone has stable moisture content during the vegetation season, with values around the water field capacity. Large changes in soil moisture were observed while rainfall. These changes depend on the volume
A Global Model for Circumgalactic and Cluster-core Precipitation
Voit, G. Mark; Meece, Greg; Li, Yuan; O'Shea, Brian W.; Bryan, Greg L.; Donahue, Megan
2017-08-01
We provide an analytic framework for interpreting observations of multiphase circumgalactic gas that is heavily informed by recent numerical simulations of thermal instability and precipitation in cool-core galaxy clusters. We start by considering the local conditions required for the formation of multiphase gas via two different modes: (1) uplift of ambient gas by galactic outflows, and (2) condensation in a stratified stationary medium in which thermal balance is explicitly maintained. Analytic exploration of these two modes provides insights into the relationships between the local ratio of the cooling and freefall timescales (I.e., {t}{cool}/{t}{ff}), the large-scale gradient of specific entropy, and the development of precipitation and multiphase media in circumgalactic gas. We then use these analytic findings to interpret recent simulations of circumgalactic gas in which global thermal balance is maintained. We show that long-lasting configurations of gas with 5≲ \\min ({t}{cool}/{t}{ff})≲ 20 and radial entropy profiles similar to observations of cool cores in galaxy clusters are a natural outcome of precipitation-regulated feedback. We conclude with some observational predictions that follow from these models. This work focuses primarily on precipitation and AGN feedback in galaxy-cluster cores, because that is where the observations of multiphase gas around galaxies are most complete. However, many of the physical principles that govern condensation in those environments apply to circumgalactic gas around galaxies of all masses.
Estimation of the characteristic energy of electron precipitation
Directory of Open Access Journals (Sweden)
C. F. del Pozo
2002-09-01
Full Text Available Data from simultaneous observations (on 13 February 1996, 9 November 1998, and 12 February 1999 with the IRIS, DASI and EISCAT systems are employed in the study of the energy distribution of the electron precipitation during substorm activity. The estimation of the characteristic energy of the electron precipitation over the common field of view of IRIS and DASI is discussed. In particular, we look closely at the physical basis of the correspondence between the characteristic energy, the flux-averaged energy, as defined below, and the logarithm of the ratio of the green-light intensity to the square of absorption. This study expands and corrects results presented in the paper by Kosch et al. (2001. It is noticed, moreover, that acceleration associated with diffusion processes in the magnetosphere long before precipitation may be controlling the shape of the energy spectrum. We propose and test a "mixed" distribution for the energy-flux spectrum, exponential at the lower energies and Maxwellian or modified power-law at the higher energies, with a threshold energy separating these two regimes. The energy-flux spectrum at Tromsø, in the 1–320 keV range, is derived from EISCAT electron density profiles in the 70–140 km altitude range and is applied in the "calibration" of the optical intensity and absorption distributions, in order to extrapolate the flux and characteristic energy maps.Key words. Ionosphere (auroral ionosphere; particle precipitation; particle acceleration
Precipitation of kidney myosin IIA and IIB by freezing.
Dias, Decivaldo dos Santos; da Cruz, Grabriel Costa Nunes; de Sousa, Marcelo Valle; Coelho, Milton Vieira
2011-03-01
Actomyosin precipitation is a critical step in the purification of myosins. In this work, the objective was to precipitate rat kidney actomyosin and isolate myosin by freezing and thawing the soluble fraction. Kidney was homogenized in imidazole buffer, centrifuged at 45000 g for 30 min, and the supernatant was frozen at -20°C for 48 h. The supernatant was thawed at 4°C, centrifuged at 45000 g for 30 min and the precipitate washed twice with imidazole buffer pH 7.0 (with and without Triton X-100, respectively). The resulting precipitate presented a polypeptide profile in SDS/PAGE characteristic of actomyosin and expressed Mg- and K/EDTA-ATPase activity. The actomyosin complex was solubilized with ATP and Mg, and the main polypeptide, p200, was purified in a DEAE-Sepharose column. p200 was marked with anti-myosin II, co-sedimented with F-actin in the absence, but not in the presence, of ATP and was identified by MS/MS with a high Mascot score for myosin IIA. The analysis identified peptides exclusive of myosin IIB, but detected no peptides exclusive of myosin IIC.
Multifractal evaluation of simulated precipitation intensities from the COSMO NWP model
Directory of Open Access Journals (Sweden)
D. Wolfensberger
2017-12-01
Full Text Available The framework of universal multifractals (UM characterizes the spatio-temporal variability in geophysical data over a wide range of scales with only a limited number of scale-invariant parameters. This work aims to clarify the link between multifractals (MFs and more conventional weather descriptors and to show how they can be used to perform a multi-scale evaluation of model data. The first part of this work focuses on a MF analysis of the climatology of precipitation intensities simulated by the COSMO numerical weather prediction model. Analysis of the spatial structure of the MF parameters, and their correlations with external meteorological and topographical descriptors, reveals that simulated precipitation tends to be smoother at higher altitudes, and that the mean intermittency is mostly influenced by the latitude. A hierarchical clustering was performed on the external descriptors, yielding three different clusters, which correspond roughly to Alpine/continental, Mediterranean and temperate regions. Distributions of MF parameters within these three clusters are shown to be statistically significantly different, indicating that the MF signature of rain is indeed geographically dependent. The second part of this work is event-based and focuses on the smaller scales. The MF parameters of precipitation intensities at the ground are compared with those obtained from the Swiss radar composite during three events corresponding to typical synoptic conditions over Switzerland. The results of this analysis show that the COSMO simulations exhibit spatial scaling breaks that are not present in the radar data, indicating that the model is not able to simulate the observed variability at all scales. A comparison of the operational one-moment microphysical parameterization scheme of COSMO with a more advanced two-moment scheme reveals that, while no scheme systematically outperforms the other, the two-moment scheme tends to produce larger extreme values
Multifractal evaluation of simulated precipitation intensities from the COSMO NWP model
Wolfensberger, Daniel; Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel; Berne, Alexis
2017-12-01
The framework of universal multifractals (UM) characterizes the spatio-temporal variability in geophysical data over a wide range of scales with only a limited number of scale-invariant parameters. This work aims to clarify the link between multifractals (MFs) and more conventional weather descriptors and to show how they can be used to perform a multi-scale evaluation of model data. The first part of this work focuses on a MF analysis of the climatology of precipitation intensities simulated by the COSMO numerical weather prediction model. Analysis of the spatial structure of the MF parameters, and their correlations with external meteorological and topographical descriptors, reveals that simulated precipitation tends to be smoother at higher altitudes, and that the mean intermittency is mostly influenced by the latitude. A hierarchical clustering was performed on the external descriptors, yielding three different clusters, which correspond roughly to Alpine/continental, Mediterranean and temperate regions. Distributions of MF parameters within these three clusters are shown to be statistically significantly different, indicating that the MF signature of rain is indeed geographically dependent. The second part of this work is event-based and focuses on the smaller scales. The MF parameters of precipitation intensities at the ground are compared with those obtained from the Swiss radar composite during three events corresponding to typical synoptic conditions over Switzerland. The results of this analysis show that the COSMO simulations exhibit spatial scaling breaks that are not present in the radar data, indicating that the model is not able to simulate the observed variability at all scales. A comparison of the operational one-moment microphysical parameterization scheme of COSMO with a more advanced two-moment scheme reveals that, while no scheme systematically outperforms the other, the two-moment scheme tends to produce larger extreme values and more
Okorie, Fidelis; Chibo, Nnamdi
2017-04-01
Atmospheric processes are dynamic with associated feedback mechanism. In other words, weather and climate processes are cyclical in nature. Both evaporation and precipitation are two weather processes which also form parts of basic components of hydrological cycle. Water is received in many parts of the world as precipitation. In many parts of the tropics for instance, the most important source of water is precipitation. Evaporation on the other hands is the reverse of precipitation in a hydrological cycle. It is also a reverse of the incoming radiation from the sun and atmosphere, and consequently an important component not only of water balance but also the energy balance. This study examined the nature of relationship existing between evaporation and precipitation in Imo State, Nigeria employing statistical method. Apparently, its curiosity is on to what extent does evaporation contribute to precipitation in the hydrological cycle? In the research, 20 years (1989-2009) evaporation data and precipitation data for Imo State was obtained and computed using Pearson's product moment correlation coefficient. The results showed a weak relationship between the two climate processes, which indicates an insignificant correlation. Thus, only about 1.83% of precipitation is influenced by evaporation in the study area. However, both components of the water cycle can influence each other irrespective of the level of their influences and they are important atmospheric processes essential for water balance of the earth.
Bergmans, Yvonne; Gordon, Evelyn; Eynan, Rahel
2017-12-01
This qualitative study aimed to capture the experience of living in the ambivalent space between life and death for adults with recurrent suicide attempts (RSA). It sought to expand upon an earlier study that explored the processes involved in transitioning away from RSA among adults, which revealed that occupying this ambivalent space is a crucial part of this process. Interpretive phenomenological analysis (IPA) was used. This methodology was designed to explore the lived experiences and meaning making and enabled interpretation of the multidimensional subjective experiences of RSA participants. In-depth semi-structured interviews were conducted with eight adult women with a history of RSA who had participated in a therapeutic intervention at the research site (Skills for Safer Living: A Psychosocial/Psychoeducational Intervention for People with Recurrent Suicide Attempts [SfSL/PISA]). The six stages of IPA were followed to analyse the interview data. Analysis revealed the superordinate theme, 'surviving moment to moment', which refers to a precarious state of making decisions about one's life and destiny on a moment-to-moment basis without clear commitment to either life or death. Two subordinate themes were identified: 'deciding not to die in the moment' when the participants were more invested in dying than living and 'deciding to live in the moment' when they were more invested in living than dying. The study illuminated the complex process of making decisions about ones' destiny on a moment-to-moment basis. It revealed the torment experienced when occupying this state, while paradoxically, also revealing how indecision about life and death provided a lifeline opportunity for those with RSA. Clinicians who recognize the subtle distinctions associated with this in-between state can tailor their interventions accordingly. Surviving moment to moment is characterized by a state of emotional flux and uncertainty about one's destiny, where the person has not fully
Gumbel Weibull distribution function for Sahel precipitation ...
African Journals Online (AJOL)
We computed the parameters using four computations methods such as: method of moments (MOM), maximum likelihood method (MLM), method of least squares (MLS) and probability weighted moments (PWM). To estimate the best method, firstly we used several good fit tests like: Kolmogorov-Smirnov (Ks), Chi-square, ...
The Diurnal Cycle of Diabatic Heating and TRMM Precipitation Estimates in West Africa
Davis, A. J.
2012-12-01
Numerous investigations have examined the diurnal cycle of convective activity in West Africa based exclusively on satellite observations. However, a unique opportunity exists to study this problem using combined in situ and satellite data thanks to the African Monsoon Multidisciplinary Analysis (AMMA)/NASA AMMA (NAMMA) field campaign that took place in 2006. In particular, a network of radiosonde launch sites was set up from June through September 2006, with the most intensive observations collected over parts of Niger, Nigeria, Benin, Togo, and Ghana. In the present study, composite vertical profiles of diabatic heating through the diurnal cycle are computed within this region of West Africa, based on the AMMA sounding data. Then, these heating profiles are placed within the context of precipitation estimates derived from several TRMM products for the same time period. In particular, the structures and timing of the heating profiles are compared with precipitation feature information provided by the TRMM database of the University of Utah Tropical Meteorology Group. This dataset includes precipitation features based on applying thresholds to data from several different instruments, including the PR, TMI, and VIRS. Differences in the composite diurnal timing of rainfall as detected by these various types of precipitation features are explored and compared with the signatures of convective and stratiform precipitation suggested by the observed diabatic heating. Alignment between the timing of the diabatic profiles and more-processed satellite products, such as 3B42 rain estimates, is also assessed.
Regional Analyses of Precipitation Annual Maxima in Washington State
Schaefer, M. G.
1990-01-01
Regional analyses of precipitation data were conducted using an index flood type methodology and probability weighted moments parameter estimates for the generalized extreme value distribution. Annual maximum series data were collected at 115 stations for durations of 2 and 6 hours and at 315 stations for the 24-hour duration. Because the climate in Washington State varies from arid to rain forest, the issues of homogeneity and region definition posed major problems. Those problems were circumvented by considering the state to be a heterogeneous superregion. Climatologically homogenous subregions within the superregion were defined in terms of mean annual precipitation (MAP) rather than geographic location. The subregional values of the coefficients of variation Cv and skew γ were found to vary systematically with MAP across the superregion. This allowed the superregional values of Cv and γ to be expressed as continuous variables instead of conventional fixed values and eliminated the boundary problems normally associated with subregion definition. The values of Cv and γ for the superregion were found to be largest for arid areas and shorter durations. Smaller values of Cv and γ were associated with humid and rain forest environments. All subregional solutions were within, or near, the extreme value type II family.
New DMSP Database of Precipitating Auroral Electrons and Ions.
Redmon, Robert J; Denig, William F; Kilcommons, Liam M; Knipp, Delores J
2017-08-01
Since the mid 1970's, the Defense Meteorological Satellite Program (DMSP) spacecraft have operated instruments for monitoring the space environment from low earth orbit. As the program evolved, so to have the measurement capabilities such that modern DMSP spacecraft include a comprehensive suite of instruments providing estimates of precipitating electron and ion fluxes, cold/bulk plasma composition and moments, the geomagnetic field, and optical emissions in the far and extreme ultraviolet. We describe the creation of a new public database of precipitating electrons and ions from the Special Sensor J (SSJ) instrument, complete with original counts, calibrated differential fluxes adjusted for penetrating radiation, estimates of the total kinetic energy flux and characteristic energy, uncertainty estimates, and accurate ephemerides. These are provided in a common and self-describing format that covers 30+ years of DMSP spacecraft from F06 (launched in 1982) through F18 (launched in 2009). This new database is accessible at the National Centers for Environmental Information (NCEI) and the Coordinated Data Analysis Web (CDAWeb). We describe how the new database is being applied to high latitude studies of: the co-location of kinetic and electromagnetic energy inputs, ionospheric conductivity variability, field aligned currents and auroral boundary identification. We anticipate that this new database will support a broad range of space science endeavors from single observatory studies to coordinated system science investigations.
New DMSP database of precipitating auroral electrons and ions
Redmon, Robert J.; Denig, William F.; Kilcommons, Liam M.; Knipp, Delores J.
2017-08-01
Since the mid-1970s, the Defense Meteorological Satellite Program (DMSP) spacecraft have operated instruments for monitoring the space environment from low Earth orbit. As the program evolved, so have the measurement capabilities such that modern DMSP spacecraft include a comprehensive suite of instruments providing estimates of precipitating electron and ion fluxes, cold/bulk plasma composition and moments, the geomagnetic field, and optical emissions in the far and extreme ultraviolet. We describe the creation of a new public database of precipitating electrons and ions from the Special Sensor J (SSJ) instrument, complete with original counts, calibrated differential fluxes adjusted for penetrating radiation, estimates of the total kinetic energy flux and characteristic energy, uncertainty estimates, and accurate ephemerides. These are provided in a common and self-describing format that covers 30+ years of DMSP spacecraft from F06 (launched in 1982) to F18 (launched in 2009). This new database is accessible at the National Centers for Environmental Information and the Coordinated Data Analysis Web. We describe how the new database is being applied to high-latitude studies of the colocation of kinetic and electromagnetic energy inputs, ionospheric conductivity variability, field-aligned currents, and auroral boundary identification. We anticipate that this new database will support a broad range of space science endeavors from single observatory studies to coordinated system science investigations.
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
Skill assessment of precipitation nowcasting in Mediterranean Heavy Precipitation Events
Bech, Joan; Berenguer, Marc
2013-04-01
Very short-term precipitation forecasting (i.e nowcasting) systems may provide valuable support in the weather surveillance process as they allow to issue automated early warnings for heavy precipitation events (HPE) as reviewed recently by Pierce et al. (2012). The need for warnings is essential in densely populated regions of small catchments, such as those typically found in Mediterranean coastal areas, prone to flash-floods. Several HPEs that occurred in NE Spain are analyzed using a nowcasting system based on the extrapolation of rainfall fields observed with weather radar following a Lagrangian approach developed and tested successfully in previous studies (Berenguer et al. 2005, 2011). Radar-based nowcasts, with lead times up to 3 h, are verified here against quality-controlled weather radar quantitative precipitation estimates and also against a dense network of raingauges. The basic questions studied are the dependence of forecast quality with lead time and rainfall amounts in several high-impact HPEs such as the 7 September 2005 Llobregat Delta river tornado outbreak (Bech et al. 2007) or the 2 November 2008 supercell tornadic thunderstorms (Bech et al. 2011) - both cases had intense rainfall rates (30' amounts exceeding 38.2 and 12.3 mm respectively) and daily values above 100 mm. Verification scores indicated that forecasts of 30' precipitation amounts provided useful guidance for lead times up to 60' for moderate intensities (up to 1 mm in 30') and up to 2.5h for lower rates (above 0.1 mm). On the other hand correlations of radar estimates and forecasts exceeded Eulerian persistence of precipitation estimates for lead times of 1.5 h for moderate intensities (up to 0.8 mm/h). We complete the analysis with a discussion on the reliability of threshold to lead time dependence based on the event-to-event variability found. This work has been done in the framework of the ProFEWS project (CGL2010-15892). References Bech J, N Pineda, T Rigo, M Aran, J Amaro, M
Moment Conditions Selection Based on Adaptive Penalized Empirical Likelihood
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Yunquan Song
2014-01-01
Full Text Available Empirical likelihood is a very popular method and has been widely used in the fields of artificial intelligence (AI and data mining as tablets and mobile application and social media dominate the technology landscape. This paper proposes an empirical likelihood shrinkage method to efficiently estimate unknown parameters and select correct moment conditions simultaneously, when the model is defined by moment restrictions in which some are possibly misspecified. We show that our method enjoys oracle-like properties; that is, it consistently selects the correct moment conditions and at the same time its estimator is as efficient as the empirical likelihood estimator obtained by all correct moment conditions. Moreover, unlike the GMM, our proposed method allows us to carry out confidence regions for the parameters included in the model without estimating the covariances of the estimators. For empirical implementation, we provide some data-driven procedures for selecting the tuning parameter of the penalty function. The simulation results show that the method works remarkably well in terms of correct moment selection and the finite sample properties of the estimators. Also, a real-life example is carried out to illustrate the new methodology.
Wavelet-based moment invariants for pattern recognition
Chen, Guangyi; Xie, Wenfang
2011-07-01
Moment invariants have received a lot of attention as features for identification and inspection of two-dimensional shapes. In this paper, two sets of novel moments are proposed by using the auto-correlation of wavelet functions and the dual-tree complex wavelet functions. It is well known that the wavelet transform lacks the property of shift invariance. A little shift in the input signal will cause very different output wavelet coefficients. The autocorrelation of wavelet functions and the dual-tree complex wavelet functions, on the other hand, are shift-invariant, which is very important in pattern recognition. Rotation invariance is the major concern in this paper, while translation invariance and scale invariance can be achieved by standard normalization techniques. The Gaussian white noise is added to the noise-free images and the noise levels vary with different signal-to-noise ratios. Experimental results conducted in this paper show that the proposed wavelet-based moments outperform Zernike's moments and the Fourier-wavelet descriptor for pattern recognition under different rotation angles and different noise levels. It can be seen that the proposed wavelet-based moments can do an excellent job even when the noise levels are very high.
τ dipole moments via radiative leptonic τ decays
Energy Technology Data Exchange (ETDEWEB)
Eidelman, S. [Budker Institute of Nuclear Physics SB RAS,Novosibirsk 630090 (Russian Federation); Novosibirsk State University,Novosibirsk 630090 (Russian Federation); Epifanov, D. [Budker Institute of Nuclear Physics SB RAS,Novosibirsk 630090 (Russian Federation); Novosibirsk State University,Novosibirsk 630090 (Russian Federation); The University of Tokyo,7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033 (Japan); Fael, M. [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics,University of Bern, CH-3012 Bern (Switzerland); Mercolli, L. [Federal Office of Public Health FOPH,CH-3003 Bern (Switzerland); Passera, M. [INFN - Sezione di Padova,I-35131 Padova (Italy)
2016-03-21
We propose a new method to probe the magnetic and electric dipole moments of the τ lepton using precise measurements of the differential rates of radiative leptonic τ decays at high-luminosity B factories. Possible deviations of these moments from the Standard Model values are analyzed in an effective Lagrangian approach, thus providing model-independent results. Analytic expressions for the relevant non-standard contributions to the differential decay rates are presented. Earlier proposals to probe the τ dipole moments are examined. A detailed feasibility study of our method is performed in the conditions of the Belle and Belle II experiments at the KEKB and Super-KEKB colliders, respectively. This study shows that our approach, applied to the planned full set of Belle II data for radiative leptonic τ decays, has the potential to improve the present experimental bound on the τ anomalous magnetic moment. On the contrary, its foreseen sensitivity is not expected to lower the current experimental limit on the τ electric dipole moment.
Quantum Interference Contribution to the Dipole Moment of Diatomic Molecules.
Oliveira de Sousa, David Wilian; Nascimento, Marco Antonio Chaer
2018-02-08
The interference energy partitioning analysis method developed by our group and used to study the nature of the chemical bond was extended to partition the electric dipole moment in quasi-classical and interference contributions. Our results show that interference participates in charge displacement in polar molecules, providing, directly or indirectly, a relevant contribution for the total dipole moment. A linear correlation was found between the interference contribution of the dipole moment from the bond electron group, μ INT (bond), and the difference of electronegativity of the atoms which form the bond, ΔX AB . This interesting result reinforces the fact that electronegativity is not a property of an atom alone, but rather a property of the atom in the molecule and that ΔX AB can only be associated with that part of the total charge displacement resulting from the formation of the chemical bond. The partitioning of the total dipole moment into quasi-classical and interference contributions provides new insights about the reasons for the failure of the ΔX AB criterion in predicting the correct orientation of the dipole moment in several molecules. The results of the present work also bring additional evidence for the previously proposed mechanism of formation of polar bonds.
'Deal with It. Name It': the diagnostic moment in film.
Jutel, Thierry; Jutel, Annemarie
2017-09-01
The moment a serious diagnosis is announced creates an important crisis for a patient, as it shifts their sense of self and of their future potential. This essay discusses the creative representation and use of this diagnostic moment in film narratives. Using Still Alice, A Late Quartet, Wit and Cléo from 5 to 7 as examples, we describe how each of these uses the diagnostic moment in relation to narrative construction and characterisation in recognisable ways. We associate the diagnostic moment with certain narrative and visual devices that are frequently implemented in films as means for character development, and for managing the audience's empathy. This is the case whether or not the diagnosis is contested or accepted, and whether the diagnostic moment is the frame for the narrative, or a closing device. By analysing its representation in film, we emphasise the cultural significance of diagnosis as a life-transforming event. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Moment arms of the muscles crossing the anatomical shoulder
Ackland, David C; Pak, Ponnaren; Richardson, Martin; Pandy, Marcus G
2008-01-01
The objective of the present study was to determine the instantaneous moment arms of 18 major muscle sub-regions crossing the glenohumeral joint during coronal-plane abduction and sagittal-plane flexion. Muscle moment-arm data for sub-regions of the shoulder musculature during humeral elevation are currently not available. The tendon-excursion method was used to measure instantaneous muscle moment arms in eight entire upper-extremity cadaver specimens. Significant differences in moment arms were reported across sub-regions of the deltoid, pectoralis major, latissimus dorsi, subscapularis, infraspinatus and supraspinatus (P shoulder muscles of broad origins into sub-regions highlighted distinct functional differences across those sub-regions. Most significantly, we found that the superior sub-region of the pectoralis major had the capacity to exert substantial torque in flexion, whereas the middle and inferior sub-regions tended to behave as a stabilizer and extensor, respectively. Knowledge of moment arm differences between muscle sub-regions may assist in identifying the functional effects of muscle sub-region tears, assist surgeons in planning tendon reconstructive surgery, and aid in the development and validation of biomechanical computer models used in implant design. PMID:18691376
Adaptive moment closure for parameter inference of biochemical reaction networks.
Schilling, Christian; Bogomolov, Sergiy; Henzinger, Thomas A; Podelski, Andreas; Ruess, Jakob
2016-11-01
Continuous-time Markov chain (CTMC) models have become a central tool for understanding the dynamics of complex reaction networks and the importance of stochasticity in the underlying biochemical processes. When such models are employed to answer questions in applications, in order to ensure that the model provides a sufficiently accurate representation of the real system, it is of vital importance that the model parameters are inferred from real measured data. This, however, is often a formidable task and all of the existing methods fail in one case or the other, usually because the underlying CTMC model is high-dimensional and computationally difficult to analyze. The parameter inference methods that tend to scale best in the dimension of the CTMC are based on so-called moment closure approximations. However, there exists a large number of different moment closure approximations and it is typically hard to say a priori which of the approximations is the most suitable for the inference procedure. Here, we propose a moment-based parameter inference method that automatically chooses the most appropriate moment closure method. Accordingly, contrary to existing methods, the user is not required to be experienced in moment closure techniques. In addition to that, our method adaptively changes the approximation during the parameter inference to ensure that always the best approximation is used, even in cases where different approximations are best in different regions of the parameter space. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Valence Topological Charge-Transfer Indices for Dipole Moments
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Francisco Torrens
2003-01-01
Full Text Available New valence topological charge-transfer indices are applied to the calculation of dipole moments. The algebraic and vector semisum charge-transfer indices are defined. The combination of the charge-transfer indices allows the estimation of the dipole moments. The model is generalized for molecules with heteroatoms. The ability of the indices for the description of the molecular charge distribution is established by comparing them with the dipole moments of a homologous series of phenyl alcohols. Linear and non-linear correlation models are obtained. The new charge-transfer indices improve the multivariable non-linear regression equations for the dipole moment. When comparing with previous results, the variance decreases 92%. No superposition of the corresponding GkÃ¢Â€Â“Jk and GkV Ã¢Â€Â“ JkV pairs is observed. This diminishes the risk of co-linearity. Inclusion of the oxygen atom in the p-electron system is beneficial for the description of the dipole moment, owing to either the role of the additional p orbitals provided by the heteroatom or the role of steric factors in the p-electron conjugation. Linear and non-linear correlations between the fractal dimension and various descriptors point not only to a homogeneous molecular structure but also to the ability to predict and tailor drug properties.
Momentous Discoveries on Mars: Science outside the MEP pathways
Easter, R. W.; Delitsky, M. L.; Lamassoure, E. S.; Mars Outpost Team
2003-05-01
The Mars Exploration Program has recently defined 4 Pathways to explore Mars in the 2009-2020 timeframe. However, some "momentous" discoveries could be made by missions now in progress that are not addressed by the pathways. In this poster, we look at 17 discoveries of different types that could be made on Mars, of varying scientific interest, and levels of "momentousness", and how future missions could be engineered to investigate these discoveries in a more urgent timeframe. Discoveries involving evidence of water, or clear signatures of ancient or extant life are those having high "momentousness". These future missions would be designed to have: 1) a more regional focus, 2) a quicker on-site response to interesting transient phenomena, or 3) longer baseline observations of the momentous phenomena observed (utilizing, for example, long-duration power sources). Also considered are discoveries that would induce or support a more accelerated human presence on Mars, such as biosignatures, resource recovery, etc. The Mars Outpost Team seeks further input from the Mars community about other possible momentous discoveries that could be made, as well as ways to respond to them (types of missions, instruments, spacecraft (orbiters, landers, rovers, airplanes, etc.))
Three-Dimensional Multi-fluid Moment Simulation of Ganymede
Wang, L.; Germaschewski, K.; Hakim, A.; Bhattacharjee, A.; Dong, C.
2016-12-01
Plasmas in space environments, such as solar wind and Earth's magnetosphere, are often constituted of multiple species. Conventional MHD-based, single-fluid systems, have additional complications when multiple fluid species are introduced. We suggest space application of an alternative multi-fluid moment approach, treating each species on equal footing using exact evolution equations for moments of their distribution function, and electromagnetic fields through full Maxwell equations. Non-ideal effects like Hall effect, inertia, and even tensorial pressures, are self-consistently embedded without the need to explicitly solve a complicated Ohm's law. Previously, we have benchmarked this approach in classical test problems like the Orszag-Tang vortex and GEM reconnection challenge problem. Recently, we performed three-dimensional two-fluid simulation of the magnetosphere of Ganymede, using both five-moment (scalar pressures) and ten-moment (tensorial pressures) models. In both models, the formation of Alfven wing structure due to subsonic inflow is correctly captured, and the magnetic field data agree well with in-situ measurements from the Galileo flyby G8. The ten-moment simulation also showed the contribution of pressure tensor divergence to the reconnecting electric field. Initial results of coupling to state-of-art global simulation codes like OpenGGCM will also be shown, which will in the future provide a rigorous way for integration of ionospheric physics.
Limnological aspects of acid precipitation
Energy Technology Data Exchange (ETDEWEB)
Hendrey, G.R. (ed.)
1978-01-01
Lakes and streams in parts of Norway, Sweden, Canada, and the United States are being severely impacted by acidic precipitation. Scientists meeting at Sagamore, New York, agreed that this is the most serious limnological problem today. The factor responsible for determining the sensitivity of surface waters to acidification is alkalinity derived by weathering of soils and bedrock in the watershed. Acidification, defined as a reduction in alkalinity, can be quantified if preacidification alkalinity data exist, but often they do not. Data on pH and Ca from surface waters in areas not affected by acid precipitation were compared to similar data from areas which receive precipitation with a weighted average hydrogen ion concentration of pH < 4.6. A semiquantitative estimation of surface water acidification can be made for lakes and streams, where earlier chemistry data are lacking, based on this analysis of pH and Ca data. Biological responses to acidification range from a reduction in numbers of species of algae and zooplankton to complete elimination of all fish life. Major biological processes such as primary production and decomposition may be altered leading to an accumulation of plant material and organic debris within lakes and streams. Increased concentrations of aluminum from the ..mu..g/l to mg/l range have been found at levels shown to be toxic to fish. These elevated levels apparently result from the exchange of H/sup +/ and Al in the watershed. There also appears to be a relationship between lake acidification and the accumulation of mercury in fish. Problems of aluminum analysis received detailed attention, and watershed mass balances, comparative watershed studies, whole lake manipulations, synoptic surveys, and the liming of acidified waters were discussed. A priority-rated list of recommendations for research was presented.
Changing precipitation extremes in Europe
van den Besselaar, E. J. M.; Klein Tank, A. M. G.; van der Schrier, G.
2010-09-01
A growing number of studies indicate trends in precipitation extremes over Europe during recent decades. These results are generally based on descriptive indices of extremes which occur on average once (or several times) each year (or season). An example is the maximum one-day precipitation amount per year. Extreme value theory complements the descriptive indices, in order to evaluate the intensity and frequency of more rare events. Trends in more rare extremes are difficult to detect, because per definition only few events exist in the observational series. Although single extreme events cannot be simply and directly attributed to anthropogenic climate change, as there is always a finite chance that the event in question might have occurred naturally, the odds may have shifted to make some of them more likely than in an unchanging climate (IPCC, 2007). In this study we focus on climate extremes defined as rare events within the statistical reference distribution of rainfall that is monitored daily at a particular place. We examine the daily precipitation series from the European Climate Assessment and Dataset (ECA&D) project. Comparisons will be made between the trends in modest extremes detected using the descriptive indices and the trends in more rare extremes determined by fitting an extreme value distribution to the data in consecutive 20-yr periods of the record. The trends in multi-year return levels are determined for groups of stations in several subregions of Europe. Because the typical record length is about 50 yr, we will assess the trends in events that occur on average up to once in 50 yr.
Recent Developments on Discontinuous Precipitation
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Zięba P.
2017-06-01
Full Text Available The discontinuous precipitation (DP belongs to a group of diffusive solid state phase transformations during which the formation of a new phase is heterogeneous and limited to a migrating reaction front (RF. The use of analytical electron microscopy provided reliable information that there is no differences in the diffusion rate at the stationary grain boundary and moving RF of DP reaction. On the other hand, the use of “in situ” transmission electron microscopy observations indicated the importance of stop-go motion or oscillatory movement of the RF.
Precipitating antibodies in mycoplasma infection.
Menonna, J; Chmel, H; Menegus, M; Dowling, P; Cook, S
1977-01-01
The effectiveness of counterimmunoelectrophoresis (CIEP) for detecting human precipitating antibodies to mcyoplasma antigen was compared with the conventional complement fixation (CF) method in a double-blind experiment. Fifty-one sera from patients suspected of having acute mycoplasma infection were tested by both techniques. Dense precipitin lines to mycoplasma antigen developed in 28 sera with CIEP. Twenty-six of 28 had elevated CF titers to this antigen. No precipitin bands were observed in sera with low antibody titers to mycoplasma. These findings indicate that the CIEP test is a specific method for reliably detecting elevated serum CF antibody levels in patients with acute or recent mycoplasma infection. PMID:328527
GPM Ground Validation Pluvio Precipitation Gauges OLYMPEX V1
National Aeronautics and Space Administration — The GPM Ground Validation Pluvio Precipitation Gauges OLYMPEX dataset contains one-minute precipitation rate and precipitation accumulation measurements, as well as...
Kells, Meredith; Rogers, Jayne; Oppenheimer, Sarah C; Blaine, Kevin; McCabe, Margaret; McGrath, Ellen; Woodring, Barbara; Geller, Alan C
2013-01-01
This article explores the topic of smoking cessation counseling for parents in the context of pediatric hospitalization. Teachable moments, a widely used concept in the literature, uses three key concepts including perception of risk, emotional response, and self-concept to precipitate change (McBride, Health Education Research, 18 [McBride, 2003], 156-170). The interweaving of these concepts with institutional systems; clinically trained personnel; parental smoking considerations; parent presence; and external supports, or collectively the novel idea of the "capturable moment", may allow for an increased rate of parental smoking cessation. Using these concepts, the authors constructed a hospital model for pediatric nursing efforts in parental smoking cessation. The pilot study built on this framework in February 2010 began enrolling parents of hospitalized pediatric patients into two intervention groups to motivate smoking cessation. Starting in September 2010, new electronic medical record-based systems of identifying parents who smoke were implemented in the hopes of enhancing enrollment numbers and streamlining recruitment. It is hoped that by introducing this process and framework, there will be increased national dialogue related to secondhand smoke (SHS) exposure, routine screening for SHS exposure, and nursing recognition of teachable moments. © 2013 Wiley Periodicals, Inc.
Impact of Aerosols on Convective Clouds and Precipitation
Tao, Wei-Kuo; Chen, Jen-Ping; Li, Zhanqing; Wang, Chien; Zhang, Chidong; Li, Xiaowen
2012-01-01
Aerosols are a critical.factor in the atmospheric hydrological cycle and radiation budget. As a major agent for clouds to form and a significant attenuator of solar radiation, aerosols affect climate in several ways. Current research suggests that aerosols have a major impact on the dynamics, microphysics, and electrification properties of continental mixed-phase convective clouds. In addition, high aerosol concentrations in urban environments could affect precipitation variability by providing a significant source of cloud condensation nuclei (CCN). Such pollution . effects on precipitation potentially have enormous climatic consequences both in terms of feedbacks involving the land surface via rainfall as well as the surface energy budget and changes in latent heat input to the atmosphere. Basically, aerosol concentrations can influence cloud droplet size distributions, the warm-rain process, the cold-rain process, cloud-top heights, the depth of the mixed-phase region, and the occurrence of lightning. Recently, many cloud resolution models (CRMs) have been used to examine the role of aerosols on mixed-phase convective clouds. These modeling studies have many differences in terms of model configuration (two- or three-dimensional), domain size, grid spacing (150-3000 m), microphysics (two-moment bulk, simple or sophisticated spectral-bin), turbulence (1st or 1.5 order turbulent kinetic energy (TKE)), radiation, lateral boundary conditions (i.e., closed, radiative open or cyclic), cases (isolated convection, tropical or midlatitude squall lines) and model integration time (e.g., 2.5 to 48 hours). Among these modeling studies, the most striking difference is that cumulative precipitation can either increase or decrease in response to higher concentrations of CCN. In this presentation, we review past efforts and summarize our current understanding of the effect of aerosols on convective precipitation processes. Specifically, this paper addresses the following topics
On the Mass Balance of Asphaltene Precipitation
DEFF Research Database (Denmark)
Andersen, Simon Ivar; Lira-Galeana, C.; Stenby, Erling Halfdan
2001-01-01
In the evaluation of experimental data as well as in calculation of phase equilibria the necessity of the application of mass balances is obvious. In the case of asphaltenes the colloidal nature of these compounds may highly affect the mass balance. In the present paper several experiments...... are performed in order to check the consistency of mass balances within asphaltene precipitation. Asphaltenes are precipitated in two step processes either by changing temperature or by changes in precipitant with increasing precipitation power. This has been performed for three different oils. The data...... indicates that in temperature experiments as well as in solvent series experiments the precipitation of heavy asphaltenes affects the following precipitation of lighter asphaltenes. In both cases the mass balance using standard separation techniques cannot be closed, as less material is precipitated...
One-Particle Measurement of the Antiproton Magnetic Moment
DiSciacca, J.; Marable, K.; Gabrielse, G.; Ettenauer, S.; Tardiff, E.; Kalra, R.; Fitzakerley, D.W.; George, M.C.; Hessels, E.A.; Storry, C.H.; Weel, M.; Grzonka, D.; Oelert, W.; Sefzick, T.
2013-01-01
The antiproton $(\\bar{p})$ magnetic moment $\\mu \\bar{p} = \\mu_{\\bar{p}} S/(\\bar{h}/2)$ is proportional to its spin $S$. A single trapped $\\bar{p}$ is used for the first time to measure the $\\bar{p}$ magnetic moment in nuclear magnetons, giving $\\mu_\\bar{p}/\\mu N = -2.792 845 \\pm 0.000 012$. The 4.4 parts per million (ppm) uncertainty is 680 times smaller than previously realized. Comparing to the proton moment $\\mu_{p} = \\mu_{p} S/\\bar{h}/2)$ measured using the same method and trap electrodes gives $\\mu_{\\bar{p}}/\\mu_{p} = -1.000 000 \\pm 0.000 005$ to 5 ppm, consistent with the prediction of the CPT theorem.
Moments of the three-parameter Fermi distribution
Zhang, L.; Gao, Y.; Zheng, H.; Huang, M. R.; Liu, X.
2017-11-01
The moments 〈rm〉 of the spherical three-parameter Fermi distribution (3pF) are presented for m = 1 to 8 as a function of the parameter w, the half-density radius c and the diffuseness parameter a through the introduced parameter β = πa/c, which can be applied to study the neutron skin in neutron rich nuclei. The general expression of the moment can be written as the combination of integrals In(k,w) with k = c/a. The errors of the analytic moments 〈rm〉 are estimated with the typical values of the parameters in 3pF compared with the numerical results.
Progress on the measurement of the francium anapole moment
Sheng, Dong; Hood, Jonathan; Lynam, Steven; Orozco, Luis; Gomez, Eduardo; Aubin, Seth; Gwinner, Gerald; Behr, John; Pearson, Matthew; Jackson, Peter; Melconian, Dan; Flambaum, Victor; Sprouse, Gene
2010-03-01
We present the current status of the experimental effort towards the measurement of the anapole moment in francium. The anapole is a parity violating, time-reversal conserving nuclear moment that arises from the weak interaction among nucleons. The anapole moment is nuclear spin dependent (nsd) and sensitive to the configuration of nuclear structure. Our experimental scheme is to perform a direct measurement of the nsd parity violation, by driving a parity forbidden E1 transition between hyperfine ground states in a series of francium isotopes inside a blue detuned dipole trap at the electric anti-node of a microwave cavity. We explore theoretical aspects and experimental requirements on the possible tests using rubidium isotopes. The experiment will be at the ISAC radioactive beam facility of TRIUMF. Work supported by NSF and DOE USA, NSERC and NRC Canada, CONACYT Mexico.
Spins, moments and charge radii beyond $^{48}$Ca
Neyens, G; Rajabali, M M; Hammen, M; Blaum, K; Froemmgen, N E; Garcia ruiz, R F; Kreim, K D; Budincevic, I
Laser spectroscopy of $^{49-54}$Ca is proposed as a continuation of the experimental theme initiated with IS484 “Ground-state properties of K-isotopes from laser and $\\beta$-NMR spectroscopy” and expanded in INTC-I-117 “Moments, Spins and Charge Radii Beyond $^{48}$Ca.” It is anticipated that the charge radii of these isotopes can show strong evidence for the existence of a sub-shell closure at N=32 and could provide a first tentative investigation into the existence of a shell effect at N=34. Furthermore the proposed experiments will simultaneously provide model-independent measurements of the spins, magnetic moments and quadrupole moments of $^{51,53}$Ca permitting existing and future excitation spectra to be pinned to firm unambiguous ground states.
Charge radii and nuclear moments around {sup 132}Sn
Energy Technology Data Exchange (ETDEWEB)
Le Blanc, F.; Cabaret, L.; Cottereau, E.; Crawford, J.E.; Essabaa, S.; Genevey, J.; Horn, R.; Huber, G.; Lassen, J.; Lee, J.K.P.; Le Scornet, G.; Obert, J.; Oms, J.; Ouchrif, A.; Pinard, J.; Roussiere, B.; Sauvage, J.; Verney, D
2004-04-05
Laser spectroscopy measurements have been carried out on the very neutron-rich tin isotopes with the COMPLIS experimental setup. Using the 5s{sup 2}5p{sup 23}P{sub 0} {yields} 5s{sup 2}5p6s {sup 3}P{sub 1} optical transition, hyperfine spectra of {sup 126-132}Sn and {sup 125m,127m,129m-131m}Sn where recorded for the first time. The variation of the mean square charge radius ({delta} < r{sup 2} >) between these nuclei and the nuclear moments of the isomers and the odd isotopes were thus measured. From the quadrupole moments values, all these nuclei appear to be spherical. The experimental magnetic moments are thus compared with the Schmidt values calculations. Moreover, the measured {delta} < r{sup 2} > are compared with several mean field calculations.
Combining minutiae triplets and quaternion orthogonal moments for fingerprint verification
Haloui, Lamyae; En-Nahnahi, Noureddine; Ouatik, Said El Alaoui
2017-05-01
We introduce a hybrid fingerprint recognition method built from minutiae and quaternion orthogonal moments. The proposed algorithm includes four steps: extraction of the minutiae triplets (m-triplets), first pass of triplets minutiae matching, validation step of these triplets by characterizing their neighboring gray-level image information through feature vectors of quaternion radial moments, and an adequate similarity measure. By boosting the local minutiae matching step, we avoid consolidation and global matching. To show the added-value of our method, several algorithms for extracting and matching m-triplets are considered and an experimental comparison is established. Experiments are carried out using all four parts of the FVC2004 dataset. Results indicate that the combination of the geometrical features and the quaternion radial moments of the m-triplets leads to an improvement in the overall fingerprint matching performance and demonstrate the expected gain of integrating a validation step in an m-triplets based fingerprint matching algorithm.
Lapped Block Image Analysis via the Method of Legendre Moments
Directory of Open Access Journals (Sweden)
El Fadili Hakim
2003-01-01
Full Text Available Research investigating the use of Legendre moments for pattern recognition has been performed in recent years. This field of research remains quite open. This paper proposes a new technique based on block-based reconstruction method (BBRM using Legendre moments compared with the global reconstruction method (GRM. For alleviating the blocking artifact involved in the processing, we propose a new approach using lapped block-based reconstruction method (LBBRM. For the problem of selecting the optimal number of moment used to represent a given image, we propose the maximum entropy principle (MEP method. The main motivation of the proposed approaches is to allow fast and efficient reconstruction algorithm, with improvement of the reconstructed images quality. A binary handwritten musical character and multi-gray-level Lena image are used to demonstrate the performance of our algorithm.
Theoretical Expectations for the Muon's Electric Dipole Moment
Feng, J L; Shadmi, Y; Feng, Jonathan L; Matchev, Konstantin T.; Shadmi, Yael
2001-01-01
We examine the muon's electric dipole moment $\\dmu$ from a variety of theoretical perspectives. We point out that the reported deviation in the muon's g-2 can be due partially or even entirely to a new physics contribution to the muon's {\\em electric} dipole moment. In fact, the recent g-2 measurement provides the most stringent bound on $\\dmu$ to date. This ambiguity could be definitively resolved by the dedicated search for $\\dmu$ recently proposed. We then consider both model-independent and supersymmetric frameworks. Under the assumptions of scalar degeneracy, proportionality, and flavor conservation, the theoretical expectations for $\\dmu$ in supersymmetry fall just below the proposed sensitivity. However, non-degeneracy can give an order of magnitude enhancement, and lepton flavor violation can lead to $\\dmu$ of order $10^{-22}$ e cm, two orders of magnitude above the sensitivity of the $\\dmu$ experiment. We present compact expressions for leptonic dipole moments and lepton flavor violating amplitudes. ...
Fluxonium-Based Artificial Molecule with a Tunable Magnetic Moment
Directory of Open Access Journals (Sweden)
A. Kou
2017-08-01
Full Text Available Engineered quantum systems allow us to observe phenomena that are not easily accessible naturally. The LEGO®-like nature of superconducting circuits makes them particularly suited for building and coupling artificial atoms. Here, we introduce an artificial molecule, composed of two strongly coupled fluxonium atoms, which possesses a tunable magnetic moment. Using an applied external flux, one can tune the molecule between two regimes: one in which the ground-excited state manifold has a magnetic dipole moment and one in which the ground-excited state manifold has only a magnetic quadrupole moment. By varying the applied external flux, we find the coherence of the molecule to be limited by local flux noise. The ability to engineer and control artificial molecules paves the way for building more complex circuits for quantum simulation and protected qubits.
Solution of the Stieltjes truncated matrix moment problem
Directory of Open Access Journals (Sweden)
Vadim M. Adamyan
2005-01-01
Full Text Available The truncated Stieltjes matrix moment problem consisting in the description of all matrix distributions \\(\\boldsymbol{\\sigma}(t\\ on \\([0,\\infty\\ with given first \\(2n+1\\ power moments \\((\\mathbf{C}_j_{n=0}^j\\ is solved using known results on the corresponding Hamburger problem for which \\(\\boldsymbol{\\sigma}(t\\ are defined on \\((-\\infty,\\infty\\. The criterion of solvability of the Stieltjes problem is given and all its solutions in the non-degenerate case are described by selection of the appropriate solutions among those of the Hamburger problem for the same set of moments. The results on extensions of non-negative operators are used and a purely algebraic algorithm for the solution of both Hamburger and Stieltjes problems is proposed.
Magnetization moment recovery using Kelvin transformation and Fourier analysis
Baratchart, L.; Leblond, J.; Lima, E. A.; Ponomarev, D.
2017-10-01
In the present work, we consider a magnetization moment recovery problem, that is finding integral of the vector function (over its compact support) whose divergence constitutes a source term in the Poisson equation. We outline derivation of explicit asymptotic formulas for estimation of the net magnetization moment vector of the sample in terms of partial data for the vertical component of the magnetic field measured in the plane above it. For this purpose, two methods have been developed: the first one is based on approximate projections onto spherical harmonics in Kelvin domain while the second stems from analysis in Fourier domain following asymptotic continuation of the data. Recovery results obtained by both methods agree and are illustrated numerically by plotting formulas for net moment components with respect to the size of the measurement area.
Seo, B. C.; Bradley, A.; Krajewski, W. F.
2015-12-01
The recent upgrade of dual-polarization with NEXRAD radars has assisted in improving the characterization of microphysical processes in precipitation and thus has enabled precipitation estimation based on the identified precipitation types. While this polarimetric capability promises the potential for the enhanced accuracy in quantitative precipitation estimation (QPE), recent studies show that the polarimetric estimates are still affected by uncertainties arising from the radar beam geometry/sampling space associated with the vertical variability of precipitation. The authors, first of all, focus on evaluating the NEXRAD hydrometeor classification product using ground reference data (e.g., ASOS) that provide simple categories of the observed precipitation types (e.g., rain, snow, and freezing rain). They also investigate classification uncertainty features caused by the variability of precipitation between the ground and the altitudes where radar samples. Since this variability is closely related to the atmospheric conditions (e.g., temperature) at near surface, useful information (e.g., critical thickness and temperature profile) that is not available in radar observations is retrieved from the numerical weather prediction (NWP) model data such as Rapid Refresh (RAP)/High Resolution Rapid Refresh (HRRR). The NWP retrieved information and polarimetric radar data are used together to improve the accuracy of precipitation type identification at near surface. The authors highlight major improvements and discuss limitations in the real-time application.
Resonances and dipole moments in dielectric, magnetic, and magnetodielectric cylinders
DEFF Research Database (Denmark)
Dirksen, A.; Arslanagic, Samel; Breinbjerg, Olav
2011-01-01
An eigenfunction solution to the problem of plane wave scattering by dielectric, magnetic, and magnetodielectric cylinders is used for a systematic investigation of their resonances. An overview of the resonances with electric and magnetic dipole moments, needed in, e.g., the synthesis of metamat......An eigenfunction solution to the problem of plane wave scattering by dielectric, magnetic, and magnetodielectric cylinders is used for a systematic investigation of their resonances. An overview of the resonances with electric and magnetic dipole moments, needed in, e.g., the synthesis...
Polynomial Approximation on Unbounded Subsets and the Markov Moment Problem
Directory of Open Access Journals (Sweden)
Octav Olteanu
2013-09-01
Full Text Available We start this review paper by recalling some known and relatively recent results in polynomial approximation on unbounded subsets. These results allow approximation of nonnegative continuous functions with compact support contained in the first quadrant by sums of tensor products of positive polynomials in each separate variable, on the positive semiaxes. Consequently, we characterize the existence of solution of a two dimensional Markov moment problem in terms of products of quadratic forms. Secondly, one proves some applications of abstract results on the extension of linear operators with two constraints to the Markov moment problem. Two applications related to this last part are considered.
Indirect Inference for Stochastic Differential Equations Based on Moment Expansions
Ballesio, Marco
2016-01-06
We provide an indirect inference method to estimate the parameters of timehomogeneous scalar diffusion and jump diffusion processes. We obtain a system of ODEs that approximate the time evolution of the first two moments of the process by the approximation of the stochastic model applying a second order Taylor expansion of the SDE s infinitesimal generator in the Dynkin s formula. This method allows a simple and efficient procedure to infer the parameters of such stochastic processes given the data by the maximization of the likelihood of an approximating Gaussian process described by the two moments equations. Finally, we perform numerical experiments for two datasets arising from organic and inorganic fouling deposition phenomena.
Quantum Electromagnetic Nonlinearity Affecting Charges and Dipole Moments
Adorno, T. C.; Gitman, D. M.; Shabad, A. E.; Shishmarev, A. A.
2017-03-01
Due to the nonlinearity of QED, a static charge becomes a magnetic dipole if placed in a magnetic field, and a magnetic monopole on the background is a combination of constant electric and magnetic fields. Already without external field, the cubic Maxwell equation for the field of a point charge has a soliton solution with a finite field energy and finite potential, the energy-momentum vector of a moving soliton being the same as that of a point massive particle. Equations are given for self-coupling dipole moments. Any theoretically found value for a multipole moment of a baryon or a meson should be subjected to nonlinear renormalization.
Small dead-time expansion in counting distributions and moments
Ackermann, J.; Hogreve, H.
2010-03-01
Considering type I counters affected by a dead-time τ, we study the τ expansion of the probabilities and moments of the underlying stochastic renewal process. For the counting distributions and probabilities we extend results from the literature and analyse their approximation properties. Our results show, in particular, that for increasing counting numbers ever larger orders of the τ expansion are required for accurate approximations. Furthermore, the τ expansion for the first and second moments are obtained; their series is proved to coincide with the respective long time asymptotics. This asymptotics is demonstrated to converge exponentially fast to the exact quantities for growing time.
Balancing in moments of vulnerability while dancing the dialectic.
Saltzberg, Christine W
2011-01-01
Questions about the existence of horizontal violence and the forms it takes dominate the literature. To move the dialogue forward, this article proffers the thesis that it is through a deeper understanding of moments of vulnerability and adult epistemological development that we may best alter the occurrence and continuance of horizontal violence in the nursing profession. The constructive development tradition has laid important groundwork for considering moments of vulnerability wherein which horizontal violence may begin and be perpetuated and explains how it has become so pervasive in the nursing field. New solutions are proposed and directions for further inquiry suggested.
Nonlinear Radon Transform Using Zernike Moment for Shape Analysis
Directory of Open Access Journals (Sweden)
Ziping Ma
2013-01-01
Full Text Available We extend the linear Radon transform to a nonlinear space and propose a method by applying the nonlinear Radon transform to Zernike moments to extract shape descriptors. These descriptors are obtained by computing Zernike moment on the radial and angular coordinates of the pattern image's nonlinear Radon matrix. Theoretical and experimental results validate the effectiveness and the robustness of the method. The experimental results show the performance of the proposed method in the case of nonlinear space equals or outperforms that in the case of linear Radon.
Electric dipole moments as a test of supersymmetric unification
Dimopoulos, Savas K; Dimopoulos, S; Hall, L J
1995-01-01
In a class of supersymmetric grand unified theories, including those based on the gauge group SO(10), there are new contributions to the electric dipole moments of the neutron and electron, which arise as a heavy top quark effect. These contributions arise from CKM-like phases, not from phases of the supersymmetry breaking operators, and can be reliably computed in terms of the parameters of the weak scale supersymmetric theory. For the expected ranges of these parameters, the electric dipole moments of the neutron and the electron are predicted to be close to present experimental limits.
A model for right-handed neutrino magnetic moments
Aparici, Alberto; Santamaria, Arcadi; Wudka, José
2010-07-01
A simple extension of the standard model providing Majorana magnetic moments to right-handed neutrinos is presented. The model contains, in addition to the standard model particles and right-handed neutrinos, just a singly charged scalar and a vector-like charged fermion. The phenomenology of the model is analysed and its implications in cosmology, astrophysics and lepton flavour violating processes are extracted. If light enough, the charged particles responsible for the right-handed neutrino magnetic moments could copiously be produced at the Large Hadron Collider.
Projection Operators and Moment Invariants to Image Blurring
Czech Academy of Sciences Publication Activity Database
Flusser, Jan; Suk, Tomáš; Boldyš, Jiří; Zitová, Barbara
2015-01-01
Roč. 37, č. 4 (2015), s. 786-802 ISSN 0162-8828 R&D Projects: GA ČR GA13-29225S; GA ČR GAP103/11/1552 Institutional support: RVO:67985556 Keywords : Blurred image * N-fold rotation symmetry * projection operators * image moments * moment invariants * blur invariants * object recognition Subject RIV: JD - Computer Applications, Robotics Impact factor: 6.077, year: 2015 http://library.utia.cas.cz/separaty/2014/ZOI/flusser-0434521.pdf
Determination of the magnetic moment of $^{140}$Pr
Kowalska, M; Kreim, K D; Krieger, A R; Litvinov, Y
We propose to measure the nuclear magnetic moment of the neutron-deficient isotope $^{140}$Pr using collinear laser spectroscopy at the COLLAPS experiment. This nuclide is one of two nuclear systems for which a modulated electron capture decay has been observed in hydrogen-like ions in a storage ring. The firm explanation of the observed phenomenon is still missing but some hypotheses suggest an interaction of the unpaired electron with the surrounding magnetic fields of the ring. In order to verify or discard these hypotheses the magnetic moment of $^{140}$Pr is required since this determines the energy of the 1s hyperfine splitting.
Valley filtering due to orbital magnetic moment in bilayer graphene
Park, Chang-Soo
2018-01-01
We investigate the effect of valley-dependent orbital magnetic moment on the transmission of quasiparticles through biased bilayer graphene npn and pnp junctions in the presence of out-of-plane magnetic field. It is shown that the valley-polarized Zeeman-like energy splitting, due to the interaction of orbital magnetic moment with magnetic field, can suppress the transmission of quasiparticles of one valley while transmitting those of the other valley. This valley-selective transmission property can be exploited for valley filtering. We demonstrate that the npn and pnp junction, respectively, filters off the K‧-valley and K-valley particles, with nearly perfect degree of filtration.
Estimation of instantaneous moment arms of lower-leg muscles.
Spoor, C W; van Leeuwen, J L; Meskers, C G; Titulaer, A F; Huson, A
1990-01-01
Muscle moment arms at the human knee and ankle were estimated from muscle length changes measured as a function of joint flexion angle in cadaver specimens. Nearly all lower-leg muscles were studied: extensor digitorum longus, extensor hallucis longus, flexor digitorum longus, flexor hallucis longus, gastrocnemius lateralis, gastrocnemius medialis, peroneus brevis, peroneus longus, peroneus tertius, plantaris, soleus, tibialis anterior, and tibialis posterior. Noise in measured muscle length was filtered by means of quintic splines. Moment arms of the mm. gastrocnemii appear to be much more dependent on joint flexion angles than was generally assumed by other investigators. Some consequences for earlier analyses are mentioned.
Hladíková, Radka
2010-01-01
Title: Data Profiling Author: Radka Hladíková Department: Department of Software Engineering Supervisor: Ing. Vladimír Kyjonka Supervisor's e-mail address: Abstract: This thesis puts mind on problems with data quality and data profiling. This Work analyses and summarizes problems of data quality, data defects, process of data quality, data quality assessment and data profiling. The main topic is data profiling as a process of researching data available in existing...
Sensitivity of the simulated precipitation to changes in convective relaxation time scale
Directory of Open Access Journals (Sweden)
S. K. Mishra
2010-10-01
Full Text Available The paper describes the sensitivity of the simulated precipitation to changes in convective relaxation time scale (TAU of Zhang and McFarlane (ZM cumulus parameterization, in NCAR-Community Atmosphere Model version 3 (CAM3. In the default configuration of the model, the prescribed value of TAU, a characteristic time scale with which convective available potential energy (CAPE is removed at an exponential rate by convection, is assumed to be 1 h. However, some recent observational findings suggest that, it is larger by around one order of magnitude. In order to explore the sensitivity of the model simulation to TAU, two model frameworks have been used, namely, aqua-planet and actual-planet configurations. Numerical integrations have been carried out by using different values of TAU, and its effect on simulated precipitation has been analyzed. The aqua-planet simulations reveal that when TAU increases, rate of deep convective precipitation (DCP decreases and this leads to an accumulation of convective instability in the atmosphere. Consequently, the moisture content in the lower- and mid- troposphere increases. On the other hand, the shallow convective precipitation (SCP and large-scale precipitation (LSP intensify, predominantly the SCP, and thus capping the accumulation of convective instability in the atmosphere. The total precipitation (TP remains approximately constant, but the proportion of the three components changes significantly, which in turn alters the vertical distribution of total precipitation production. The vertical structure of moist heating changes from a vertically extended profile to a bottom heavy profile, with the increase of TAU. Altitude of the maximum vertical velocity shifts from upper troposphere to lower troposphere. Similar response was seen in the actual-planet simulations. With an increase in TAU from 1 h to 8 h, there was a significant improvement in the simulation of the seasonal mean precipitation. The fraction
Sulfate removal from waste chemicals by precipitation.
Benatti, Cláudia Telles; Tavares, Célia Regina Granhen; Lenzi, Ervim
2009-01-01
Chemical oxidation using Fenton's reagent has proven to be a viable alternative to the oxidative destruction of organic pollutants in mixed waste chemicals, but the sulfate concentration in the treated liquor was still above the acceptable limits for effluent discharge. In this paper, the feasibility of sulfate removal from complex laboratory wastewaters using barium and calcium precipitation was investigated. The process was applied to different wastewater cases (two composite samples generated in different periods) in order to study the effect of the wastewater composition on the sulfate precipitation. The experiments were performed with raw and oxidized wastewater samples, and carried out according to the following steps: (1) evaluate the pH effect upon sulfate precipitation on raw wastewaters at pH range of 2-8; (2) conduct sulfate precipitation experiments on raw and oxidized wastewaters; and (3) characterize the precipitate yielded. At a concentration of 80 g L(-1), barium precipitation achieved a sulfate removal up to 61.4% while calcium precipitation provided over 99% sulfate removal in raw and oxidized wastewaters and for both samples. Calcium precipitation was chosen to be performed after Fenton's oxidation; hence this process configuration favors the production of higher quality precipitates. The results showed that, when dried at 105 degrees C, the precipitate is composed of hemidrate and anhydrous calcium sulfate ( approximately 99.8%) and trace metals ( approximately 0.2%: Fe, Cr, Mn, Co, Ag, Mg, K, Na), what makes it suitable for reuse in innumerous processes.
Energy Technology Data Exchange (ETDEWEB)
Matrosov, Sergey
2010-12-15
The main objective of this project was to develop, validate and apply remote sensing methods to retrieve vertical profiles of precipitation over the DOE ARM CART sites using currently available remote sensors. While the ARM Program invested very heavily into developments of remote sensing methods and instruments for water vapor and non-precipitating cloud parameter retrievals, precipitation retrievals and studies lagged behind. Precipitation, however, is a crucial part of the water cycle, and without detailed information on rainfall and snowfall, significant improvements in the atmospheric models of different scales (i.e., one of the ARM Program's main goals) is difficult to achieve. Characterization of the vertical atmospheric column above the CART sites is also incomplete without detailed precipitation information, so developments of remote sensing methods for retrievals of parameters in precipitating cloud condition was essential. Providing modelers with retrieval results was also one of the key objectives of this research project.
Tidal Love numbers and moment-Love relations of polytropic stars
Yip, Kenny L. S.; Leung, P. T.
2017-12-01
The physical significance of tidal deformation in astronomical systems has long been known. The recently discovered universal I-Love-Q relations, which connect moment of inertia, quadrupole tidal Love number and spin-induced quadrupole moment of compact stars, also underscore the special role of tidal deformation in gravitational wave astronomy. Motivated by the observation that such relations also prevail in Newtonian stars and crucially depend on the stiffness of a star, we consider the tidal Love numbers of Newtonian polytropic stars whose stiffness is characterized by a polytropic index n. We first perturbatively solve the Lane-Emden equation governing the profile of polytropic stars through the application of the scaled delta expansion method and then formulate perturbation series for the multipolar tidal Love number about the two exactly solvable cases with n = 0 and n = 1, respectively. Making use of these two series to form a two-point Padé approximant, we find an approximate expression of the quadrupole tidal Love number, whose error is less than 2.5 × 10-5 per cent (0.39 per cent) for n ∈ [0, 1] (n ∈ [0, 3]). Similarly, we also determine the mass moments for polytropic stars accurately. Based on these findings, we are able to show that the I-Love-Q relations are in general stationary about the incompressible limit irrespective of the equation of state of a star. Moreover, for the I-Love-Q relations, there is a secondary stationary point near n ≈ 0.4444, thus showing the insensitivity to n for n ∈ [0, 1]. Our investigation clearly tracks the universality of the I-Love-Q relations from their validity for stiff stars such as neutron stars to their breakdown for soft stars.
Global Precipitation Measurement (GPM) launch, commissioning, and early operations
Neeck, Steven P.; Kakar, Ramesh K.; Azarbarzin, Ardeshir A.; Hou, Arthur Y.
2014-10-01
The Global Precipitation Measurement (GPM) mission is an international partnership co-led by NASA and the Japan Aerospace Exploration Agency (JAXA). The mission centers on the GPM Core Observatory and consists of an international network, or constellation, of additional satellites that together will provide next-generation global observations of precipitation from space. The GPM constellation will provide measurements of the intensity and variability of precipitation, three-dimensional structure of cloud and storm systems, the microphysics of ice and liquid particles within clouds, and the amount of water falling to Earth's surface. Observations from the GPM constellation, combined with land surface data, will improve weather forecast models; climate models; integrated hydrologic models of watersheds; and forecasts of hurricanes/typhoons/cylcones, landslides, floods and droughts. The GPM Core Observatory carries an advanced radar/radiometer system and serves as a reference standard to unify precipitation measurements from all satellites that fly within the constellation. The GPM Core Observatory improves upon the capabilities of its predecessor, the NASA-JAXA Tropical Rainfall Measuring Mission (TRMM), with advanced science instruments and expanded coverage of Earth's surface. The GPM Core Observatory carries two instruments, the NASA-supplied GPM Microwave Imager (GMI) and the JAXA-supplied Dual-frequency Precipitation Radar (DPR). The GMI measures the amount, size, intensity and type of precipitation, from heavy-tomoderate rain to light rain and snowfall. The DPR provides three-dimensional profiles and intensities of liquid and solid precipitation. The French Centre National d'Études Spatiales (CNES), the Indian Space Research Organisation (ISRO), the U.S. National Oceanic and Atmospheric Administration (NOAA), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), and the U.S. Department of Defense are partners with NASA and
Electrostatic precipitator for air cleaning
Energy Technology Data Exchange (ETDEWEB)
Albertsson, P.; Eriksson, R.; Vlastos, A.
1981-03-31
An electrostatic precipitator is disclosed for air cleaning wherein the air passes through in two steps: first passing through a charging portion and next through a separation portion. The charging portion includes wires positioned parallel to and between parallel metal sheets, the wires having an electric potential other than that of the metal sheets. The separation portion includes plural parallel metal sheets, each of which has an electric potential other than that of adjacent metal sheets. The charging portion includes two or more wires between each pair of metal sheets, and the metal sheets of the charging portion extend through and constitute some of the metal sheets of the separation portion, between which are disposed addition metal sheets of an odd number.
Calcium precipitate induced aerobic granulation.
Wan, Chunli; Lee, Duu-Jong; Yang, Xue; Wang, Yayi; Wang, Xingzu; Liu, Xiang
2015-01-01
Aerobic granulation is a novel biotechnology for wastewater treatment. This study refined existing aerobic granulation mechanisms as a sequencing process including formation of calcium precipitate under alkaline pH to form inorganic cores, followed by bacterial attachment and growth on these cores to form the exopolysaccharide matrix. Mature granules comprised an inner core and a matrix layer and a rim layer with enriched microbial strains. The inorganic core was a mix of different crystals of calcium and phosphates. Functional strains including Sphingomonas sp., Paracoccus sp. Sinorhizobium americanum strain and Flavobacterium sp. attached onto the cores. These functional strains promote c-di-GMP production and the expression by Psl and Alg genes for exopolysaccharide production to enhance formation of mature granules. Copyright © 2014 Elsevier Ltd. All rights reserved.
Deuteron magnetic quadrupole moment from chiral effective field theory
Liu, C. -P.; de Vries, J.; Mereghetti, E.; Timmermans, R. G. E.; van Kolck, U.
2012-01-01
We calculate the magnetic quadrupole moment (MQM) of the deuteron at leading order in the systematic expansion provided by chiral effective field theory. We take into account parity (P) and time-reversal (T) violation which, at the quark-gluon level, results from the QCD vacuum angle and
Second moment method for a family of boolean CSP
Boufkhad, Yacine
2011-01-01
The estimation of phase transitions in random boolean Constraint Satisfaction Problems (CSP) is based on two fundamental tools: the first and second moment methods. While the first moment method on the number of solutions permits to compute upper bounds on any boolean CSP, the second moment method used for computing lower bounds proves to be more tricky and in most cases gives only the trivial lower bound 0. In this paper, we define a subclass of boolean CSP covering the monotone versions of many known NP-Complete boolean CSPs. We give a method for computing non trivial lower bounds for any member of this subclass. This is achieved thanks to an application of the second moment method to some selected solutions called characteristic solutions that depend on the boolean CSP considered. We apply, as an example, this method to establish that the threshold r_{k} of monotone 1-in-k-SAT is \\log k/k\\leq r_{k}\\leq\\log^{2}k/k
Precise asymptotics for complete moment convergence in Hilbert ...
Indian Academy of Sciences (India)
... Discussion Meetings · Public Lectures · Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Proceedings – Mathematical Sciences; Volume 122; Issue 1. Precise Asymptotics for Complete Moment Convergence in Hilbert Spaces. Keang Fu Juan Chen. Volume 122 Issue 1 February 2012 ...
Rovibrational matrix elements of the multipole moments and of the ...
Indian Academy of Sciences (India)
Rovibrational matrix elements of the multipole moments ℓ up to rank 10 and of the linear polarizability of the H2 molecule in the condensed phase have been computed taking into account the effect of the intermolecular potential. Comparison with gas phase matrix elements shows that the effect of solid state interactions is ...
New Experiments to Measure the Muon Anomalous Gyromagnetic Moment
Eads, M
2015-01-01
The magnetic moment is a fundamental property of particles. The measurement of these magnetic moments and the comparison with the values predicted by the standard model of particle physics is a way to test our understanding of the fundamental building blocks of our world. In some cases, such as for the electron, this comparison has resulted in confirmation of the standard model with incredible precision. In contrast, the magnetic moment of the muon has shown a long-standing disagreement in the measured and the predicted value. There is currently a tantalizing three-standard-deviation difference between the current best measurement (with a precision of 0.54 ppm) and the state-of-the-art standard model prediction. This represents one of the very few experimental hints for physics beyond the standard model. There are currently two major experimental efforts underway to improve the precision of the muon magnetic moment measurement. The first is an evolution of the E-821 experiment, originally located at Brookhave...
Geometric interpretation of the Zero-Moment Point
van Oort, Gijs; Stramigioli, Stefano
In this article we show that the concept of screws and wrenches gives us tools to geometrically establish the relation between the ground reaction wrench and the Zero-Moment Point. In order to arrive at this, we show how a wrench can be decomposed into separate components. The proposed method gives
Satellite Orbital Precessions Caused by the Octupolar Mass Moment ...
Indian Academy of Sciences (India)
2016-01-27
Jan 27, 2016 ... I consider a satellite moving around a non-spherical body of mass and equatorial radius , and calculate its orbital precessions caused by the body's octupolar mass moment 4. I consider only the effects averaged over one orbital period of the satellite. I give exact formulas, not restricted to any special ...
Rovibrational matrix elements of the multipole moments and of the ...
Indian Academy of Sciences (India)
a maximum of 2% from the free molecule matrix elements. 2. Theoretical details and method of computation. In a linear molecule, the strength of the 2 -pole moment tensor of ranki is characterized by a single (scalar) component Q , and i is necessarily even valued if the molecule is centro- symmetric like H2. If we align the ...
An Extreme Black Hole with Electric Dipole Moment
Horowitz, Gary T.; Tada, Tsukasa
1996-01-01
We construct a new extreme black hole solution in toroidally compactified heterotic string theory. The black hole saturates the Bogomol'nyi bound, has zero angular momentum, but nonzero electric dipole moment. It is obtained by starting with a higher dimensional rotating charged black hole, and compactifying one direction in the plane of rotation.
Quadrupole moments of low-lying baryons with spin
Indian Academy of Sciences (India)
... spin − 3 2 + → 1 2 + transitions. Neetika Sharma Harleen Dahiya. Research Articles Volume 80 Issue 2 February 2013 pp 237-249 ... GP parameters pertaining to the two- and three-quark contributions. It is found that the CQM is successful in giving a quantitative and qualitative description of the quadrupole moments.
Outside the Box Teaching Moments: Classroom-Tested Innovations
Whalen, D. Joel; Coker, Kesha K.
2016-01-01
The 2015 Society for Marketing Advances Teaching Moments sessions offered a wide variety of teaching interventions centered on gaining students' attention, increasing class participation, using lively student-engaging demonstrations, using props during lecture, using sales technology classroom applications, using social media, and many more.…
Atomic electric dipole moments : The Schiff theorem and its corrections
Liu, C. -P.; Ramsey-Musolf, M. J.; Haxton, W. C.; Timmermans, R. G. E.; Dieperink, A. E. L.
Searches for the permanent electric dipole moments (EDMs) of diamagnetic atoms provide powerful probes of CP-violating hadronic and semileptonic interactions. The theoretical interpretation of such experiments, however, requires careful implementation of a well-known theorem by Schiff that implies a
Pseudoclassical description of relativistic spinning particles with anomalous magnetic moment
Barducci, A.
1982-12-01
We present a completely consistent lagrangian formulation for a supersymmetric test particle with an anomalous magnetic moment in the presence of an arbitrary external electromagnetic field. We show that such a description is also possible in a supersymmetrical approach without breaking supersymmetry. On leave of absence from Istituto di Fisica Teorica dell' Università di Firenze, Lgo E. Fermi 2, 50125 Florence, Italy.
A Reflection on My Teaching Practices Using Students' Math Moments
Farren, Vanessa
2008-01-01
This paper focus on the reflection of my teaching practices using students' Math Moments. I began to invest time in the past mathematical experiences of my students to better help me understand my own teaching practices. Throughout this paper I will reflect on my own teaching practice, delve into relevant literature and will use poignant math…
Preservice Teachers' In-the-Moment Teaching Decisions in Reading
Griffith, Robin
2017-01-01
This study examines the types of in-the-moment teaching decisions 97 preservice teachers made while teaching reading and how their growing bodies of teacher knowledge influenced their abilities to think, know, feel and act like a teacher (Feiman-Nemser, 2008). Findings indicated that the teacher educator's use of "metacognitive…
Prony's method and the connected-moments expansion
Fernández, Francisco M.
2013-02-01
We show that Prony's method provides the full solution to the nonlinear equations of the connected-moments expansion (CMX). Knowledge of all the parameters in the CMX ansatz is useful for the analysis of the convergence properties of the approach. Prony's method may also be suitable for the calculation of the correlation function for simple quantum-mechanical models.
On complete moment convergence for nonstationary negatively associated random variables
Directory of Open Access Journals (Sweden)
Mi-Hwa Ko
2016-05-01
Full Text Available Abstract The purpose of this paper is to establish the complete moment convergence for nonstationary negatively associated random variables satisfying the weak mean domination condition. The result is an improvement of complete convergence in Marcinkiewicz-Zygmund-type SLLN for negatively associated random variables in Kuczmaszewska (Acta Math. Hung. 128:116-130, 2010.
The Historical and Literary Moment of Njabulo S. Ndebele ...
African Journals Online (AJOL)
Borrowing the historical construct of the “interregnum” – as understood by Italian Marxist philosopher Antonio Gramsci – Gordimer viewed the power struggle in South Africa as one between an oppressive and unjust old order outstaying its historical moment and the new order of liberty and democracy, still uncertain about its ...
Higher moments of the natural parameterization for SLE curves
Rezaei, Mohammad A.; Zhan, Dapeng
2017-02-01
In this paper, we will show that the higher moments of the natural parametrization of SLE curves in any bounded domain in the upper half plane is finite. We prove this by estimating the probability that an SLE curve gets near n given points.
Moments of Inertia of Disks and Spheres without Integration
Hong, Seok-Cheol; Hong, Seok-In
2013-01-01
Calculation of moments of inertia is often challenging for introductory-level physics students due to the use of integration, especially in non-Cartesian coordinates. Methods that do not employ calculus have been described for finding the rotational inertia of thin rods and other simple bodies. In this paper we use the parallel axis theorem and…
A calculation method of cracking moment for the high strength ...
Indian Academy of Sciences (India)
Abstract. In this study, a method is given to calculate cracking moments of high strength reinforced concrete beams under the effect of pure torsion. To determine the method, both elastic and plastic theories were used. In this method, dimensions of beam cross-section were considered besides stirrup and longitudinal ...
Transitory Moments in Infant/Toddler Play: Agentic Imagination
Ridgway, Avis; Li, Liang; Quiñones, Gloria
2016-01-01
Studying relationships in infant/toddler play, using visual narrative methodology to identify transitory moments, supports our current research on babies and toddlers. We use Vygotsky's theorisation of play to understand children's affective and intellectual aspirations in play. The theoretical discussion, using cultural-historical concepts,…
SNO results and neutrino magnetic moment solution to the solar ...
Indian Academy of Sciences (India)
Kamiokande (SK) experiments (1258 days) and also the new results that came from Sudbury Neu- trino Observatory (SNO) charge current (CC) and elastic scattering (ES) experiments considering that the solar neutrino deficit is due to the interaction of neutrino transition magnetic moment with the solar magnetic field.
Effective equations for the quantum pendulum from momentous quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Hernandez, Hector H.; Chacon-Acosta, Guillermo [Universidad Autonoma de Chihuahua, Facultad de Ingenieria, Nuevo Campus Universitario, Chihuahua 31125 (Mexico); Departamento de Matematicas Aplicadas y Sistemas, Universidad Autonoma Metropolitana-Cuajimalpa, Artificios 40, Mexico D. F. 01120 (Mexico)
2012-08-24
In this work we study the quantum pendulum within the framework of momentous quantum mechanics. This description replaces the Schroedinger equation for the quantum evolution of the system with an infinite set of classical equations for expectation values of configuration variables, and quantum dispersions. We solve numerically the effective equations up to the second order, and describe its evolution.
A Hybrid Joint Moment Ratio Test for Financial Time Series
P.A. Groenendijk (Patrick); A. Lucas (André); C.G. de Vries (Casper)
1998-01-01
textabstractWe advocate the use of absolute moment ratio statistics in conjunction with standard variance ratio statistics in order to disentangle linear dependence, non-linear dependence, and leptokurtosis in financial time series. Both statistics are computed for multiple return horizons
Knee Osteoarthritis Affects the Distribution of Joint Moments During Gait
Zeni, Joseph A; Higginson, Jill S.
2010-01-01
Alterations in lower extremity kinetics have been shown to exist in persons with knee osteoarthritis (OA), however few investigations have examined how the intersegmental coordination of the lower extremity kinetic chain varies in the presence of knee joint pathology. The objective of this study was to evaluate the how knee OA and walking speed affect total support moment and individual joint contributions to the total support moment. Fifteen healthy subjects and 30 persons with knee OA participated in 3D walking analysis at constrained (1.0 m/s), self-selected and fastest tolerable walking speeds. Individual joint contributions to total support moment were analyzed using separate ANOVAs with one repeated measure (walking speed). Linear regression analysis was used to evaluate the relationship between walking speed and joint contribution. Persons with knee OA reduced the contribution of the knee joint when walking at constrained (p=0.04) and self-selected walking speeds (p=0.009). There was a significant increase in the ankle contribution and a significant decrease in the hip contribution when walking speed was increased (Pknee OA is not responsible for the reduction in knee joint moments, rather this change is likely due to alterations in the neuromuscular strategy of the lower extremity kinetic chain in response to joint pain or muscle weakness. PMID:20510618
Precise asymptotics for complete moment convergence in Hilbert ...
Indian Academy of Sciences (India)
(Math. Sci.) Vol. 122, No. 1, February 2012, pp. 87–97. c Indian Academy of Sciences. Precise asymptotics for complete moment convergence in Hilbert spaces ... School of Statistics and Mathematics, Zhejiang Gongshang University, .... Now we start to introduce some Propositions, and the proof of our main result is based.
an evaluation of solutions to moment method of biochemical oxygen ...
African Journals Online (AJOL)
HOD
This paper evaluated selected solutions of moment method in respect to Biochemical Oxygen Demand (BOD) kinetics with the aim of ascertain error free solution. Domestic-institutional wastewaters were collected two-weekly for three months from waste-stabilization ponds in Obafemi Awolowo University, Ile-Ife.
Searches for permanent electric dipole moments in Radium isotopes
Willmann, L.; Jungmann, K.; Wilschut, H. W.
2010-01-01
Permanent electric dipole moments are uniquely sensitive to sources of T and P violation in fundamental interactions. In particular radium isotopes offer the largest intrinsic sensitivity. We want to explore the prospects for utilizing the high intense beams from HIE-ISOLDE to boost the statistical sensitivity of search for EDMs in atomic radium.
Statistical moments in superposition models and strongly intensive measures
Broniowski, Wojciech; Olszewski, Adam
2017-06-01
First, we present a concise glossary of formulas for composition of standard, cumulant, factorial, and factorial cumulant moments in superposition (compound) models, where final particles are created via independent emission from a collection of sources. Explicit mathematical formulas for the composed moments are given to all orders. We discuss the composition laws for various types of moments via the generating-function methods and list the formulas for the unfolding of the unwanted fluctuations. Second, the technique is applied to the difference of the scaled multiplicities of two particle types. This allows for a systematic derivation and a simple algebraic interpretation of the so-called strongly intensive fluctuation measures. With the help of the formalism we obtain several new strongly intensive measures involving higher-rank moments. The reviewed as well as the new results may be useful in investigations of mechanisms of particle production and event-by-event fluctuations in high-energy nuclear and hadronic collisions, and in particular in the search for signatures of the QCD phase transition at a finite baryon density.
Aesthetic Relationships and Ethics in "The Oh Fuck Moment"
Breel, Astrid
2015-01-01
This article explores the aesthetics and ethics of participatory performance through "The Oh Fuck Moment" by Hannah Jane Walker and Chris Thorpe, a performance that aesthetically explores ethically troubling material and manipulation. Ethical criticism of participatory art in recent years has focused on the way the audience member is…
Innovative Moments in Grief Therapy: Reconstructing Meaning Following Perinatal Death
Alves, Daniela; Mendes, Ines; Goncalves, Miguel M.; Neimeyer, Robert A.
2012-01-01
This article presents an intensive analysis of a good outcome case of constructivist grief therapy with a bereaved mother, using the Innovative Moments Coding System (IMCS). Inspired by M. White and D. Epston's narrative therapy, the IMCS conceptualizes therapeutic change as resulting from the elaboration and expansion of unique outcomes (or as we…
Higher moments of scattered light fields by heterodyne analysis
Harris, M.; Paerson, G. N.; Hill, C. A.; Vaughan, J. M.
1994-10-01
A simple scattering experiment employing heterodyne detection and operating in Gaussian scattering regime (with large number of illuminated independent scatterers) is shown to yield experimental values of higher-order moments of scattered light intensity distribution in agreement with theoretical predictions. This permits assessment of Gaussian behavior. Laser light scattering from a rotating glass screen is used in the study.
The Teachable Moment After Cancer Diagnosis: Perceptions From Oncology Nurses.
Karvinen, Kristina; Bruner, Brenda; Truant, Tracy
2015-11-01
To determine oncology nurses' perspectives of the receptiveness of survivors to receiving health behavior guidance, with secondary purposes to (a) explore other elements of oncology nurses' perceptions of the teachable moment and (b) examine differences in outcomes between American and Canadian nurses . Cross-sectional survey. In- and outpatient oncology nursing departments in the United States and Canada. 310 members of the Canadian Association of Nurses in Oncology (CANO/ACIO) and the Oncology Nursing Society (ONS) who currently care for patients . Oncology nurses recruited through emails distributed through the CANO/ACIO and ONS Listservs completed online investigator-developed surveys. Measures related to oncology nurses' perceptions of survivors' receptiveness to health behavior change counseling and the teachable moment (i.e., general receptiveness, perceived benefits, guidance and referral seeking, long- and short-term effectiveness, best time, and best resources). Oncology nurses reported that survivors were receptive to receiving guidance on health behaviors, particularly during teachable moments after diagnosis and during treatment. They also perceived that a fairly low percentage of survivors asked for guidance about health behavior change; relatively few made improvements to their health behaviors. Survivors are reported to be interested in receiving guidance concerning health behavior change during key teachable moments. Oncology nurses may need to initiate conversations with survivors, offer education regarding the benefits of positive health behavior change, and provide ongoing support throughout the cancer trajectory. Oncology nurses may use findings from the current study to guide their health behavior change counseling with survivors .
Searches for permanent electric dipole moments in Radium isotopes
Willmann, L.; Jungmann, K.; Wilschut, H.W.
2010-01-01
Permanent electric dipole moments are uniquely sensitive to sources of T and P violation in fundamental interactions. In particular radium isotopes offer the largest intrinsic sensitivity. We want to explore the prospects for utilizing the high intense beams from HIE-ISOLDE to boost the statistical
Masses and magnetic moments of triple heavy flavour baryons in ...
Indian Academy of Sciences (India)
The predicted masses are found to attain a saturated value with respect to variation in p beyond the power index > 1.0. Using the spin-flavour structure of the constituting quarks and by defining effective mass of the confined quarks within the baryons, the magnetic moments are computed with no additional free parameters ...
More about the moment of inertia of Mars
Kaula, William M.; Sleep, Norman H.; Phillips, Roger J.
1989-01-01
Differences between Mars and other terrestrial planets are discussed. Unlike other terrestrial planets, Mars has two nonhydrostatic components of moments of inertia that are nearly equal. The most probable value of I/MR-squared is slightly less than 0.3650.
A calculation method of cracking moment for the high strength ...
Indian Academy of Sciences (India)
In this study, a method is given to calculate cracking moments of high strength reinforced concrete beams under the effect of pure torsion. To determine the method, both elastic and plastic theories were used. In this method, dimensions of beam cross-section were considered besides stirrup and longitudinal reinforcements.
Permanent Electric Dipole Moment Search in 129Xe
Grasdijk, Jan; Bluemler, P.; Almendinger, F.; Heil, Werner; Jungmann, Klaus-Peter; Karpuk, S.; Krause, Hans-Joachim; Offenhaeuser, Andreas; Repetto, M.; Schmidt, Ulrich; Sobolev, Y.; Willmann, Lorenz; Zimmer, Stefan
2017-01-01
A permanent electric dipole moment (EDM) implies breakdown of P (parity) and T (time reversal) symmetries. Provided CPT holds, this implies CP violation. Observation of an EDM at achievable experimental sensitivity would provide unambiguous evidence for physics beyond the Standard Model and limits
The Public Health Journey: The Meaning and the Moment
Koh, Howard K.
2013-01-01
The public health journey is a remarkable one, filled with twists and turns as well as risks and rewards. Because promoting the health of others represents a mission brimming with meaning, our professional work is also profoundly personal. At this extraordinary moment in our nation's public health history, I reflect on the purpose of the…
experimental validation of optimum resistance moment of concrete ...
African Journals Online (AJOL)
user
Fibre-Reinforced Plastics (FRPs) have been suggested as suitable reinforcement for concrete structures among other solutions to combat corrosion problems in steel reinforced concrete. This paper presents the experimental validation of optimum resistance moment of concrete slabs reinforced with Carbon-Fibre ...
Experimental validation of optimum resistance moment of concrete ...
African Journals Online (AJOL)
Fibre-Reinforced Plastics (FRPs) have been suggested as suitable reinforcement for concrete structures among other solutions to combat corrosion problems in steel reinforced concrete. This paper presents the experimental validation of optimum resistance moment of concrete slabs reinforced with Carbon-Fibre ...
Cannon, Forest; Ralph, F. Martin; Wilson, Anna M.; Lettenmaier, Dennis P.
2017-12-01
Atmospheric rivers (ARs) account for more than 90% of the total meridional water vapor flux in midlatitudes, and 25-50% of the annual precipitation in the coastal western United States. In this study, reflectivity profiles from the Global Precipitation Measurement Dual-Frequency Precipitation Radar (GPM-DPR) are used to evaluate precipitation and temperature characteristics of ARs over the western coast of North America and the eastern North Pacific Ocean. Evaluation of GPM-DPR bright-band height using a network of ground-based vertically pointing radars along the West Coast demonstrated exceptional agreement, and comparison with freezing level height from reanalyses over the eastern North Pacific Ocean also consistently agreed, indicating that GPM-DPR can be used to independently validate freezing level in models. However, precipitation comparison with gridded observations across the western United States indicated deficiencies in GPM-DPR's ability to reproduce the spatial distribution of winter precipitation, likely related to sampling frequency. Over the geographically homogeneous oceanic portion of the domain, sampling frequency was not problematic, and significant differences in the frequency and intensity of precipitation between GPM-DPR and reanalyses highlighted biases in both satellite-observed and modeled AR precipitation. Reanalyses precipitation rates below the minimum sensitivity of GPM-DPR accounted for a 20% increase in total precipitation, and 25% of radar-derived precipitation rates were greater than the 99th percentile precipitation rate in reanalyses. Due to differences in the proportions of precipitation in convective, stratiform bright-band, and non-bright-band conditions, AR conditions contributed nearly 10% more to total precipitation in GPM-DPR than reanalyses.
Breast cancer diagnosis in digitized mammograms using curvelet moments.
Dhahbi, Sami; Barhoumi, Walid; Zagrouba, Ezzeddine
2015-09-01
Feature extraction is a key issue in designing a computer aided diagnosis system. Recent researches on breast cancer diagnosis have reported the effectiveness of multiscale transforms (wavelets and curvelets) for mammogram analysis and have shown the superiority of curvelet transform. However, the curse of dimensionality problem arises when using the curvelet coefficients and therefore a reduction method is required to extract a reduced set of discriminative features. This paper deals with this problem and proposes a feature extraction method based on curvelet transform and moment theory for mammogram description. First, we performed discrete curvelet transform and we computed the four first-order moments from curvelet coefficients distribution. Hence, two feature sets can be obtained: moments from each band and moments from each level. In this work, both sets are studied. Then, the t-test ranking technique was applied to select the best features from each set. Finally, a k-nearest neighbor classifier was used to distinguish between normal and abnormal breast tissues and to classify tumors as malignant or benign. Experiments were performed on 252 mammograms from the Mammographic Image Analysis Society (mini-MIAS) database using the leave-one-out cross validation as well as on 11553 mammograms from the Digital Database for Screening Mammography (DDSM) database using 2×5-fold cross validation. Experimental results prove the effectiveness and the superiority of curvelet moments for mammogram analysis. Indeed, results on the mini-MIAS database show that curvelet moments yield an accuracy of 91.27% (resp. 81.35 %) with 10 (resp. 8) features for abnormality (resp. malignancy) detection. In addition, empirical comparisons of the proposed method against state-of-the-art curvelet-based methods on the DDSM database show that the suggested method does not only lead to a more reduced feature set, but it also statistically outperforms all the compared methods in terms of
DEFF Research Database (Denmark)
Sunyer Pinya, Maria Antonia; Luchner, J.; Onof, C.
2017-01-01
The increase in extreme precipitation is likely to be one of the most significant impacts of climate change in cities due to increased pluvial flood risk. Hence, reliable information on changes in sub-daily extreme precipitation is needed for robust adaptation strategies. This study explores...... extreme precipitation over Denmark generated by the regional climate model (RCM) HIRHAM-ECEARTH at different spatial resolutions (8, 12, 25 and 50km), three RCM from the RiskChange project at 8km resolution and three RCMs from ENSEMBLES at 25km resolution at temporal aggregations from 1 to 48h......) are more consistent across all temporal aggregations in the representation of high-order moments and extreme precipitation. The biases in the spatial pattern of extreme precipitation change across temporal and spatial resolution. The hourly extreme value distributions of the HIRHAM-ECEARTH simulations...
Bera, Aindrila; Ghosh, Manas
2017-06-01
Present study examines the pattern of variation of electric dipole moment (μ) and polarizability (αp) of impurity doped GaAs quantum dots (QDs) under combined presence of hydrostatic pressure and temperature and in presence of noise. Noise term carries a Gaussian white character and it has been introduced to the system via two different pathways; additive and multiplicative. Profiles of μ and αp have been monitored against the variations of hydrostatic pressure (HP), temperature and the noise strength. Under a given condition of HP and temperature, application of noise prominently influences the above two properties. However, the extent of influence depends on the noise strength and the pathway through which noise is introduced. The findings divulge feasible routes to control the dipole moment and polarizability of doped QD system through the interplay between HP, temperature and noise.
Constraining the neutrino magnetic dipole moment from white dwarf pulsations
Energy Technology Data Exchange (ETDEWEB)
Córsico, A.H.; Althaus, L.G. [Grupo de Evolución Estelar y Pulsaciones, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, (1900) La Plata (Argentina); Bertolami, M.M. Miller [Instituto de Astrofísica La Plata, CONICET-UNLP, Paseo del Bosque s/n, (1900) La Plata (Argentina); Kepler, S.O. [Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Porto Alegre 91501-970, RS (Brazil); García-Berro, E., E-mail: acorsico@fcaglp.unlp.edu.ar, E-mail: althaus@fcaglp.unlp.edu.ar, E-mail: marcelo@MPA-Garching.MPG.DE, E-mail: kepler@if.ufrgs.br, E-mail: enrique.garcia-berro@upc.edu [Departament de Física Aplicada, Universitat Politècnica de Catalunya, c/Esteve Terrades 5, 08860, Castelldefels (Spain)
2014-08-01
Pulsating white dwarf stars can be used as astrophysical laboratories to constrain the properties of weakly interacting particles. Comparing the cooling rates of these stars with the expected values from theoretical models allows us to search for additional sources of cooling due to the emission of axions, neutralinos, or neutrinos with magnetic dipole moment. In this work, we derive an upper bound to the neutrino magnetic dipole moment (μ{sub ν}) using an estimate of the rate of period change of the pulsating DB white dwarf star PG 1351+489. We employ state-of-the-art evolutionary and pulsational codes which allow us to perform a detailed asteroseismological period fit based on fully DB white dwarf evolutionary sequences. Plasmon neutrino emission is the dominant cooling mechanism for this class of hot pulsating white dwarfs, and so it is the main contributor to the rate of change of period with time (Pidot) for the DBV class. Thus, the inclusion of an anomalous neutrino emission through a non-vanishing magnetic dipole moment in these sequences notably influences the evolutionary timescales, and also the expected pulsational properties of the DBV stars. By comparing the theoretical Pidot value with the rate of change of period with time of PG 1351+489, we assess the possible existence of additional cooling by neutrinos with magnetic dipole moment. Our models suggest the existence of some additional cooling in this pulsating DB white dwarf, consistent with a non-zero magnetic dipole moment with an upper limit of μ{sub ν} ∼< 10{sup -11} μ{sub B}. This bound is somewhat less restrictive than, but still compatible with, other limits inferred from the white dwarf luminosity function or from the color-magnitude diagram of the Globular cluster M5. Further improvements of the measurement of the rate of period change of the dominant pulsation mode of PG 1351+489 will be necessary to confirm our bound.
Constraining the neutrino magnetic dipole moment from white dwarf pulsations
Córsico, A. H.; Althaus, L. G.; Miller Bertolami, M. M.; Kepler, S. O.; García-Berro, E.
2014-08-01
Pulsating white dwarf stars can be used as astrophysical laboratories to constrain the properties of weakly interacting particles. Comparing the cooling rates of these stars with the expected values from theoretical models allows us to search for additional sources of cooling due to the emission of axions, neutralinos, or neutrinos with magnetic dipole moment. In this work, we derive an upper bound to the neutrino magnetic dipole moment (μν) using an estimate of the rate of period change of the pulsating DB white dwarf star PG 1351+489. We employ state-of-the-art evolutionary and pulsational codes which allow us to perform a detailed asteroseismological period fit based on fully DB white dwarf evolutionary sequences. Plasmon neutrino emission is the dominant cooling mechanism for this class of hot pulsating white dwarfs, and so it is the main contributor to the rate of change of period with time (Pi dot) for the DBV class. Thus, the inclusion of an anomalous neutrino emission through a non-vanishing magnetic dipole moment in these sequences notably influences the evolutionary timescales, and also the expected pulsational properties of the DBV stars. By comparing the theoretical Pi dot value with the rate of change of period with time of PG 1351+489, we assess the possible existence of additional cooling by neutrinos with magnetic dipole moment. Our models suggest the existence of some additional cooling in this pulsating DB white dwarf, consistent with a non-zero magnetic dipole moment with an upper limit of μν lesssim 10-11 μB. This bound is somewhat less restrictive than, but still compatible with, other limits inferred from the white dwarf luminosity function or from the color-magnitude diagram of the Globular cluster M5. Further improvements of the measurement of the rate of period change of the dominant pulsation mode of PG 1351+489 will be necessary to confirm our bound.
Identifying Isotropic Events Using a Regional Moment Tensor Inversion
Energy Technology Data Exchange (ETDEWEB)
Ford, S R; Dreger, D S; Walter, W R
2008-11-04
We calculate the deviatoric and isotropic source components for 17 explosions at the Nevada Test Site, as well as 12 earthquakes and 3 collapses in the surrounding region of the western US, using a regional time-domain full waveform inversion for the complete moment tensor. The events separate into specific populations according to their deviation from a pure double-couple and ratio of isotropic to deviatoric energy. The separation allows for anomalous event identification and discrimination between explosions, earthquakes, and collapses. Confidence regions of the model parameters are estimated from the data misfit by assuming normally distributed parameter values. We investigate the sensitivity of the resolved parameters of an explosion to imperfect Earth models, inaccurate event depths, and data with low signal-to-noise ratio (SNR) assuming a reasonable azimuthal distribution of stations. In the band of interest (0.02-0.10 Hz) the source-type calculated from complete moment tensor inversion is insensitive to velocity models perturbations that cause less than a half-cycle shift (<5 sec) in arrival time error if shifting of the waveforms is allowed. The explosion source-type is insensitive to an incorrect depth assumption (for a true depth of 1 km), and the goodness-of-fit of the inversion result cannot be used to resolve the true depth of the explosion. Noise degrades the explosive character of the result, and a good fit and accurate result are obtained when the signal-to-noise ratio (SNR) is greater than 5. We assess the depth and frequency dependence upon the resolved explosive moment. As the depth decreases from 1 km to 200 m, the isotropic moment is no longer accurately resolved and is in error between 50-200%. However, even at the most shallow depth the resultant moment tensor is dominated by the explosive component when the data have a good SNR.
The use of surface EMG in knee extensor moment prediction.
Cheng, C K; Hsiung, H S; Lai, J S
1994-10-01
A systematic method of EMG quantification is developed to estimate the isometric muscle moment directly from quantified surface EMG. This method includes the EMG Signals acquired from an acupuncture point Fu-Tu located on the quadriceps muscle group, an EMG smoothing scheme, an electromechanical time lag estimation, and a mathematical model with the polynomial regression function to quantify the EMG. Three subjects were asked to be tested on the CYBEX II dynamometer with a knee joint angle of 90 degree flexion and hip joint angle of also 90 degrees. They were asked to perform "two" trials of maximal voluntary contraction and "three" trials of free voluntary contraction of the isometric exercise. The first two trials were used to build up the quantification model, and the latter three trials served as data for the validation of the method. A Medelec MS92 EMG system with surface EMG electrodes was used to acquire the EMG Signals. In the determination of the regression order of the polynomial equations, the threshold value 0.0001 of the difference of the coefficient of determination values was used. The results of the polynomial regression orders are all 6 for three subjects, which reflects a tendency of nonlinear behavior of the EMG/moment relationship. A validation scheme was proposed to calculate the root mean square difference (RMSD) of the measured knee extensor moments from the CYBEX II dynamometer and estimated moments from the EMG quantification. The mean values of the RMSD of the three subjects were 0.0597, 0.0679 and 0.1080. These results demonstrate that the present approach can estimate the isometric muscle moment exerted by the quadriceps muscle group.
Improved Electronic Control for Electrostatic Precipitators
Johnston, D. F.
1986-01-01
Electrostatic precipitators remove particulate matter from smoke created by burning refuse. Smoke exposed to electrostatic field, and particles become electrically charged and migrate to electrically charged collecting surfaces. New microprocessor-based electronic control maintains precipitator power at maximum particulate-collection level. Control automatically senses changes in smoke composition due to variations in fuel or combustion and adjusts precipitator voltage and current accordingly. Also, sensitive yet stable fault detection provided.
Global Precipitation Measurement (GPM) Mission Development Status
Azarbarzin, Ardeshir Art
2011-01-01
Mission Objective: (1) Improve scientific understanding of the global water cycle and fresh water availability (2) Improve the accuracy of precipitation forecasts (3) Provide frequent and complete sampling of the Earth s precipitation Mission Description (Class B, Category I): (1) Constellation of spacecraft provide global precipitation measurement coverage (2) NASA/JAXA Core spacecraft: Provides a microwave radiometer (GMI) and dual-frequency precipitation radar (DPR) to cross-calibrate entire constellation (3) 65 deg inclination, 400 km altitude (4) Launch July 2013 on HII-A (5) 3 year mission (5 year propellant) (6) Partner constellation spacecraft.
Inter-comparison of the EUMETSAT H-SAF and NASA PPS precipitation products over Western Europe.
Kidd, Chris; Panegrossi, Giulia; Ringerud, Sarah; Stocker, Erich
2017-04-01
The development of precipitation retrieval techniques utilising passive microwave satellite observations has achieved a good degree of maturity through the use of physically-based schemes. The DMSP Special Sensor Microwave Imager/Sounder (SSMIS) has been the mainstay of passive microwave observations over the last 13 years forming the basis of many satellite precipitation products, including NASA's Precipitation Processing System (PPS) and EUMETSAT's Hydrological Satellite Application Facility (H-SAF). The NASA PPS product utilises the Goddard Profiling (GPROF; currently 2014v2-0) retrieval scheme that provides a physically consistent retrieval scheme through the use of coincident active/passive microwave retrievals from the Global Precipitation Measurement (GPM) mission core satellite. The GPM combined algorithm retrieves hydrometeor profiles optimized for consistency with both Dual-frequency Precipitation Radar (DPR) and GPM Microwave Imager (GMI); these profiles form the basis of the GPROF database which can be utilized for any constellation radiometer within the framework a Bayesian retrieval scheme. The H-SAF product (PR-OBS-1 v1.7) is based on a physically-based Bayesian technique where the a priori information is provided by a Cloud Dynamic Radiation Database (CDRD). Meteorological parameter constraints, derived from synthetic dynamical-thermodynamical-hydrological meteorological profile variables, are used in conjunction with multi-hydrometeor microphysical profiles and multispectral PMW brightness temperature vectors into a specialized a priori knowledge database underpinning and guiding the algorithm's Bayesian retrieval solver. This paper will present the results of an inter-comparison of the NASA PPS GPROF and EUMETSAT H-SAF PR-OBS-1 products over Western Europe for the period from 1 January 2015 through 31 December 2016. Surface radar is derived from the UKMO-derived Nimrod European radar product, available at 15 minute/5 km resolution. Initial results
Wilcox, Kevin R; Shi, Zheng; Gherardi, Laureano A; Lemoine, Nathan P; Koerner, Sally E; Hoover, David L; Bork, Edward; Byrne, Kerry M; Cahill, James; Collins, Scott L; Evans, Sarah; Gilgen, Anna K; Holub, Petr; Jiang, Lifen; Knapp, Alan K; LeCain, Daniel; Liang, Junyi; Garcia-Palacios, Pablo; Peñuelas, Josep; Pockman, William T; Smith, Melinda D; Sun, Shanghua; White, Shannon R; Yahdjian, Laura; Zhu, Kai; Luo, Yiqi
2017-10-01
Climatic changes are altering Earth's hydrological cycle, resulting in altered precipitation amounts, increased interannual variability of precipitation, and more frequent extreme precipitation events. These trends will likely continue into the future, having substantial impacts on net primary productivity (NPP) and associated ecosystem services such as food production and carbon sequestration. Frequently, experimental manipulations of precipitation have linked altered precipitation regimes to changes in NPP. Yet, findings have been diverse and substantial uncertainty still surrounds generalities describing patterns of ecosystem sensitivity to altered precipitation. Additionally, we do not know whether previously observed correlations between NPP and precipitation remain accurate when precipitation changes become extreme. We synthesized results from 83 case studies of experimental precipitation manipulations in grasslands worldwide. We used meta-analytical techniques to search for generalities and asymmetries of aboveground NPP (ANPP) and belowground NPP (BNPP) responses to both the direction and magnitude of precipitation change. Sensitivity (i.e., productivity response standardized by the amount of precipitation change) of BNPP was similar under precipitation additions and reductions, but ANPP was more sensitive to precipitation additions than reductions; this was especially evident in drier ecosystems. Additionally, overall relationships between the magnitude of productivity responses and the magnitude of precipitation change were saturating in form. The saturating form of this relationship was likely driven by ANPP responses to very extreme precipitation increases, although there were limited studies imposing extreme precipitation change, and there was considerable variation among experiments. This highlights the importance of incorporating gradients of manipulations, ranging from extreme drought to extreme precipitation increases into future climate change
Directory of Open Access Journals (Sweden)
Mahdi Golpayegani
2017-08-01
Full Text Available In recent years some studies have been done on the moment rredistribution in buildings and new methods offered for calculating of redistribution. Observations demonstrated that the combination of moment and shear force is important in analysis of reinforced concrete structures. But little research is done about the effect of redistribution by using moding in software. In order to study the effect of moment redistribution on the stability of RC moment resisting frame structures, four buildings with 4, 7, 10 and 13 story have been considered. In these models, the nonlinear behavior of elements (beam and column is considered by the use of interaction PMM hinges. The average plastic rotation was calculated by performing pushover analysis and storing stiffness matrix for 5 points and then the buckling coefficients were obtained by conducting buckling analysis. By the use of modal analysis natural frequency was calculated and it was attempted to be related the average plastic rotation with the buckling coefficients and the natural frequency. It could be concluded that increase in the plastic rotation reduce the buckling coefficients to about 96% which this amount of reduction is related to the average plastic rotation. Moreover, the buildings experience instability state when the average plastic rotation reached to 0.006 radian.
Enhanced diffusion of boron by oxygen precipitation in heavily boron-doped silicon
Torigoe, Kazuhisa; Ono, Toshiaki
2017-06-01
The enhanced diffusion of boron has been investigated by analyzing out-diffusion profiles in the vicinity of the interface between a lightly boron-doped silicon epitaxial layer and a heavily boron-doped silicon substrate with a resistivity of 8.2 mΩ cm and an oxide precipitate (O.P.) density of 108-1010 cm-3. It is found that the boron diffusion during annealing at 850-1000 °C is enhanced with the increase of the oxide precipitate density. On the basis of a model for boron diffusion mediated by silicon self-interstitials, we reveal that the enhanced diffusion is attributed to self-interstitials supersaturated as a result of the emission from oxide precipitates and the absorption by punched-out dislocations. In addition, the temperature dependence of the fraction of the self-interstitial emission obtained analyzing the diffusion enhancement well explains the morphology changes of oxide precipitates reported in literature.
Berne, A.D.; Delrieu, G.; Andrieu, H.
2005-01-01
The present study aims at a preliminary approach of multiradar compositing applied to the estimation of the vertical structure of precipitation¿an important issue for radar rainfall measurement and prediction. During the HYDROMET Integrated Radar Experiment (HIRE¿98), the vertical profile of
Gatsonis, Nikolaos A.; Chamberlin, Ryan E.; Averkin, Sergey N.
2013-01-01
The mathematical and computational aspects of the direct simulation Monte Carlo on unstructured tetrahedral grids (U3DSMC) with a Kinetic-Moment (KM) boundary conditions method are presented. The algorithms for particle injection, particle loading, particle motion, and particle tracking are presented. The KM method applicable to a subsonic or supersonic inflow/outflow boundary, couples kinetic (particle) U3DSMC properties with fluid (moment) properties. The KM method obtains the number density, temperature and mean velocity needed to define the equilibrium, drifting Maxwellian distribution at a boundary. The moment component of KM is based on the local one dimensional inviscid (LODI) boundary conditions method consistent with the 5-moment compressible Euler equations. The kinetic component of KM is based on U3DSMC for interior properties and the equilibrium drifting Maxwellian at the boundary. The KM method is supplemented with a time-averaging procedure, allows for choices in sampling-cell procedures, minimizes fluctuations and accelerates the convergence in subsonic flows. Collision sampling in U3DSMC implements the no-time-counter method and includes elastic and inelastic collisions. The U3DSMC with KM boundary conditions is validated and verified extensively with simulations of subsonic nitrogen flows in a cylindrical tube with imposed inlet pressure and density and imposed outlet pressure. The simulations cover the regime from slip to free-molecular with inlet Knudsen numbers between 0.183 and 18.27 and resulting inlet Mach numbers between 0.037 and 0.027. The pressure and velocity profiles from U3DSMC-KM simulations are compared with analytical solutions obtained from first-order and second-order slip boundary conditions. Mass flow rates from U3DSMC-KM are compared with validated analytical solutions for the entire Knudsen number regime considered. Error and sensitivity analysis is performed and numerical fractional errors are in agreement with theoretical
Salimbeni, S.; Pondrelli, S.; D'Amico, V.; Meletti, C.; Rovida, A.
2016-12-01
In the frame of the elaboration of a new seismic hazard model of Italy, the identification of the areas with homogeneous tectonic regime is needed as one of the objective elements for designing the seismic source zones.A collection of all seismic moment tensors available for Italy for earthquakes with magnitude greater than or equal to 4.0 since 1960 was gathered. It contains data from different catalogs or datasets, mainly populated by moment tensors computed through inversion of seismic waves (e.g. CMT, RCMT, GFZ and ETHZ MT and so on). However, for great earthquakes of the past, i.e. the 1962 Irpinia or the 1968 Belice earthquakes (both max Mw > 6.0) we used data obtained with other methods, but always considered the best available information for that time.All these data helped to find the predominant fault mechanism, considered the typical tectonic style for a region or, using regular grids, for all seismic areas of the Italian peninsula and regions around. To identify the most seismic regions, we used data from historical and recent instrumental seismicity (CPTI15, http://emidius.mi.ingv.it/CPTI15-DBMI15/ and INGV bulletins, http://iside.rm.ingv.it/) combined on a regular grid, obtaining seismic moment release maps. Overlapping cumulative moment tensors to seismic moment release maps, we identified regions clearly characterized by different tectonics. In particular, the extension is the principal type of deformation along most of the Apennines, somewhere interrupted by strike-slip mechanism. Compressive deformation appears in the eastern Alps, in the outer part of the northernmost sector of the Apennines, in several parts of the Adriatic Sea and in the off shore of Northern Sicily. We considered this tectonic style mapping to help with drawing seismic area sources for the new seismic hazard model of Italy.
Magnetospheric particle precipitation at Titan
Royer, Emilie; Esposito, Larry; Crary, Frank; Wahlund, Jan-Erik
2017-04-01
Although solar XUV radiation is known to be the main source of ionization in Titan's upper atmosphere around 1100 km of altitude, magnetospheric particle precipitation can also account for about 10% of the ionization process. Magnetospheric particle precipitation is expected to be the most intense on the nightside of the satelllite and when Titan's orbital position around Saturn is the closest to Noon Saturn Local Time (SLT). In addition, on several occasion throughout the Cassini mission, Titan has been observed while in the magnetosheath. We are reporting here Ultraviolet (UV) observations of Titan airglow enhancements correlated to these magnetospheric changing conditions occurring while the spacecraft, and thus Titan, are known to have crossed Saturn's magnetopause and have been exposed to the magnetosheath environnment. Using Cassini-Ultraviolet Imaging Spectrograph (UVIS) observations of Titan around 12PM SLT as our primary set of data, we present evidence of Titan's upper atmosphere response to a fluctuating magnetospheric environment. Pattern recognition software based on 2D UVIS detector images has been used to retrieve observations of interest, looking for airglow enhancement of a factor of 2. A 2D UVIS detector image, created for each UVIS observation of Titan, displays the spatial dimension of the UVIS slit on the x-axis and the time on the y-axis. In addition, data from the T32 flyby and from April 17, 2005 from in-situ Cassini instruments are used. Correlations with data from simultaneous observations of in-situ Cassini instruments (CAPS, RPWS and MIMI) has been possible on few occasions and events such as electron burst and reconnections can be associated with unusual behaviors of the Titan airglow. CAPS in-situ measurements acquired during the T32 flyby are consistent with an electron burst observed at the spacecraft as the cause of the UV emission. Moreover, on April 17, 2005 the UVIS observation displays feature similar to what could be a
Reconstruction of March-June precipitation from tree rings in central Liaoning, China
Wang, Yanchao; Liu, Yu
2016-12-01
A dendrochronological profile was generated from Chinese pines (Pinus tabulaeformis Carr.) in the Qianshan Mountains in northeastern China. Based on correlation analyses, the pattern of precipitation from March to June (P 36 ) was reconstructed using a simple linear model, which explained 42.7% of the total variance in observed precipitation from 1951 to 2012. The reconstructed P 36 series revealed a consistently increasing trend in precipitation during the twentieth century in the Qianshan Mountains. The reconstructed data showed trends that were similar to those in the variation in trends for March-June precipitation observed at the Shenyang station, the reconstructed January-May precipitation trends in Shenyang City, and the reconstructed average June-September relative humidity for Yiwulü Mountain. The reconstructed data also showed good agreement with the droughts reported in historical documents and recorded by meteorological stations in Liaoning. Spatial correlation analyses show that the reconstructed data reflect the variability in precipitation that occurs over much of northeastern China. In addition, our reconstruction showed a significant periodicity. The significant correlations between the reconstructed P 36 and the El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO) and sunspot numbers indicate that precipitation variability in the Qianshan Mountain region is probably driven by extensive atmosphere-sea interactions and solar activities.
Chen, Yilun; Fu, Yunfei
2018-01-01
The echo-top height observed by the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) has been used by some studies as an approximate calculation of the precipitating-cloud-top height to simulate radiative forcing or to identify overshooting convection. However, due to the low sensitivity ( 17 dBZ) of PR, the PR-echo-top height is lower than the actual precipitating-cloud-top height. Here, the echo-top heights of the tropical precipitating cloud detected by PR, the Cloud Profiling Radar (CPR), and the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) were investigated to evaluate the underestimation of the PR-echo-top height to the actual precipitating-cloud-top height. The results show that there were significant spatial variations in the underestimates of precipitating-cloud-top height by PR. The model simulation showed that these underestimates led to an underestimation of the radiative forcing of the Earth system, the relative error of which was 10% with 1-km underestimation and 20% to 80% with 7-km underestimation when the cloud optical thickness was fixed to 10. Therefore, the underestimates of precipitating-cloud-top height by PR should be taken into consideration when using PR-echo-top height.
Reconstruction of March-June precipitation from tree rings in central Liaoning, China
Wang, Yanchao; Liu, Yu
2017-11-01
A dendrochronological profile was generated from Chinese pines ( Pinus tabulaeformis Carr.) in the Qianshan Mountains in northeastern China. Based on correlation analyses, the pattern of precipitation from March to June ( P 36 ) was reconstructed using a simple linear model, which explained 42.7% of the total variance in observed precipitation from 1951 to 2012. The reconstructed P 36 series revealed a consistently increasing trend in precipitation during the twentieth century in the Qianshan Mountains. The reconstructed data showed trends that were similar to those in the variation in trends for March-June precipitation observed at the Shenyang station, the reconstructed January-May precipitation trends in Shenyang City, and the reconstructed average June-September relative humidity for Yiwulü Mountain. The reconstructed data also showed good agreement with the droughts reported in historical documents and recorded by meteorological stations in Liaoning. Spatial correlation analyses show that the reconstructed data reflect the variability in precipitation that occurs over much of northeastern China. In addition, our reconstruction showed a significant periodicity. The significant correlations between the reconstructed P 36 and the El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO) and sunspot numbers indicate that precipitation variability in the Qianshan Mountain region is probably driven by extensive atmosphere-sea interactions and solar activities.
Circulation factors affecting precipitation over Bulgaria
Nojarov, Peter
2017-01-01
The objective of this paper is to determine the influence of circulation factors on precipitation in Bulgaria. The study succeeds investigation on the influence of circulation factors on air temperatures in Bulgaria, as the focus here is directed toward precipitation amounts. Circulation factors are represented through two circulation indices, showing west-east or south-north transport of air masses over Bulgaria and four teleconnection indices (patterns)—North Atlantic Oscillation, East Atlantic, East Atlantic/Western Russia, and Scandinavian. Omega values at 700-hPa level show vertical motions in the atmosphere. Annual precipitation trends are mixed and not statistically significant. A significant decrease of precipitation in Bulgaria is observed in November due to the strengthening of the eastward transport of air masses (strengthening of EA teleconnection pattern) and anticyclonal weather (increase of descending motions in the atmosphere). There is also a precipitation decrease in May and June due to the growing influence of the Azores High. An increase of precipitation happens in September. All this leads to a redistribution of annual precipitation course, but annual precipitation amounts remain the same. However, this redistribution has a negative impact on agriculture and winter ski tourism. Zonal circulation has a larger influence on precipitation in Bulgaria compared to meridional. Eastward transport throughout the year leads to lower than the normal precipitation, and vice versa. With regard to the four teleconnection patterns, winter precipitation in Bulgaria is determined mainly by EA/WR teleconnection pattern, spring and autumn by EA teleconnection pattern, and summer by SCAND teleconnection pattern.
A critical consideration of magnetism and composition of (bcc) Cu precipitates in (bcc) Fe
Energy Technology Data Exchange (ETDEWEB)
Schober, M. [University of Leoben, Department of Physical Metallurgy and Materials Testing, Leoben (Austria); Montanuniversitaet Leoben, Department Metallkunde und Werkstoffpruefung, Leoben (Austria); Eidenberger, E.; Leitner, H. [University of Leoben, Department of Physical Metallurgy and Materials Testing, Leoben (Austria); Staron, P. [GKSS Research Centre, Institute of Materials Research, Geesthacht (Germany); Reith, D.; Podloucky, R. [University of Vienna, Department for Physical Chemistry, Vienna (Austria)
2010-06-15
Atom probe and small-angle neutron scattering (SANS) measurements were carried out in order to investigate the chemical composition of (bcc) Cu precipitates in a (bcc) Fe matrix. The ratio of nuclear and magnetic integrated intensities (R-value) found by SANS is compared to a theoretical model which is based on the chemical composition obtained from the atom probe data. Furthermore, density functional theory calculations were performed to derive the magnetic moment per atom and the lattice parameters of the Cu alloys modeled in terms of supercells. The calculated and measured R-values agree rather well suggesting that Fe atoms are incorporated in the Cu precipitates up to concentrations of about 50 at.%. (orig.)
Aluminosilicate Precipitation Impact on Uranium
Energy Technology Data Exchange (ETDEWEB)
WILMARTH, WILLIAM
2006-03-10
Experiments have been conducted to examine the fate of uranium during the formation of sodium aluminosilicate (NAS) when wastes containing high aluminate concentrations are mixed with wastes of high silicate concentration. Testing was conducted at varying degrees of uranium saturation. Testing examined typical tank conditions, e.g., stagnant, slightly elevated temperature (50 C). The results showed that under sub-saturated conditions uranium is not removed from solution to any large extent in both simulant testing and actual tank waste testing. This aspect was not thoroughly understood prior to this work and was necessary to avoid criticality issues when actual tank wastes were aggregated. There are data supporting a small removal due to sorption of uranium on sites in the NAS. Above the solubility limit the data are clear that a reduction in uranium concentration occurs concomitant with the formation of aluminosilicate. This uranium precipitation is fairly rapid and ceases when uranium reaches its solubility limit. At the solubility limit, it appears that uranium is not affected, but further testing might be warranted.
Higher moments method for generalized Pareto distribution in flood frequency analysis
Zhou, C. R.; Chen, Y. F.; Huang, Q.; Gu, S. H.
2017-08-01
The generalized Pareto distribution (GPD) has proven to be the ideal distribution in fitting with the peak over threshold series in flood frequency analysis. Several moments-based estimators are applied to estimating the parameters of GPD. Higher linear moments (LH moments) and higher probability weighted moments (HPWM) are the linear combinations of Probability Weighted Moments (PWM). In this study, the relationship between them will be explored. A series of statistical experiments and a case study are used to compare their performances. The results show that if the same PWM are used in LH moments and HPWM methods, the parameter estimated by these two methods is unbiased. Particularly, when the same PWM are used, the PWM method (or the HPWM method when the order equals 0) shows identical results in parameter estimation with the linear Moments (L-Moments) method. Additionally, this phenomenon is significant when r ≥ 1 that the same order PWM are used in HPWM and LH moments method.
Discontinuous precipitation in copper base alloys
Indian Academy of Sciences (India)
Administrator
Abstract. Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, η, has been calculated and predicted that if.
Meteorological features associated with unprecedented precipitation ...
Indian Academy of Sciences (India)
Unprecedented precipitation along with heavy falls occurred over many parts of India from 28th February to 2nd March 2015. Many of the stations of northwest and central India received an all time high 24 hr cumulative precipitation of March during this period. Even the national capital, New Delhi, broke all the previous ...
Asphaltene precipitates in oil production wells
DEFF Research Database (Denmark)
Kleinitz, W,; Andersen, Simon Ivar
1998-01-01
At the beginning of production in a southern German oil field, flow blockage was observed during file initial stage of production from the oil wells. The hindrance was caused by the precipitation of asphaltenes in the proximity of the borehole and in the tubings. The precipitates were of solid...
Calcium carbonate precipitation by different bacterial strains ...
African Journals Online (AJOL)
Bacteria are capable of performing metabolic activities which thereby promote precipitation of calcium carbonate in the form of calcite. In this study, it is shown that microbial mineral precipitation was a result of metabolic activities of some specific microorganisms. Concrete microorganisms were used to improve the overall ...
Discontinuous precipitation in copper base alloys
Indian Academy of Sciences (India)
Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, , has been calculated and predicted that if 100 > ± 0.1, DP is ...
Study of asphaltene precipitation by Calorimetry
DEFF Research Database (Denmark)
Verdier, Sylvain Charles Roland; Plantier, Frédéric; Bessières, David
2007-01-01
of experiments showed that weak forces determine precipitation. Indeed, isothermal titration calorimetry could not detect any clear signal although this technique can detect low-energy transitions such as liquid-liquid equilibrium and rnicellization. The second series of tests proved that precipitation caused...
Precipitation variability assessment of northeast China: Songhua ...
Indian Academy of Sciences (India)
Variability in precipitation is critical for the management of water resources. In this study, the research entropy base concept was applied to investigate spatial and temporal variability of the precipitation during 1964–2013 in the Songhua River basin of Heilongjiang Province in China. Sample entropy was applied on ...
Isotope fingerprinting of precipitation associated with western ...
Indian Academy of Sciences (India)
Precipitation at Jammu seems to have undergone intense evaporation while that from Uttarakhand suggest normal Rayleigh fractionation/distillation of the air mass as it moves from the source region to the precipitation site and/or orographic lifting. The d-excess of rainfall in Kashmir has a distinctly higher median value of ...
Measurement of acid precipitation in Norway
Arne Semb
1976-01-01
Since January 1972, chemical analysis of daily precipitation samples from about 20 background stations in Norway has been carried out on a routine basis. Air monitoring is carried out at six stations. The chemical analysis programme is: sulphate, pH and acidity in precipitation, sulphates and sulphur dioxide in air. In addition, more detailed chemical analysis of...
Meteorological features associated with unprecedented precipitation ...
Indian Academy of Sciences (India)
Naresh Kumar
2017-06-29
Jun 29, 2017 ... unprecedented precipitation event over India. It occurred due to the presence of an ... westerlies and easterlies caused unprecedented precipitation over India during the 1st week of March 2015. Keywords. Meteorological ... ies related to WDs that caused extreme weather over the Himalayan region and ...
Geoelectrical inference of mass transfer parameters using temporal moments
Day-Lewis, Frederick D.; Singha, Kamini
2008-01-01
We present an approach to infer mass transfer parameters based on (1) an analytical model that relates the temporal moments of mobile and bulk concentration and (2) a bicontinuum modification to Archie's law. Whereas conventional geochemical measurements preferentially sample from the mobile domain, electrical resistivity tomography (ERT) is sensitive to bulk electrical conductivity and, thus, electrolytic solute in both the mobile and immobile domains. We demonstrate the new approach, in which temporal moments of collocated mobile domain conductivity (i.e., conventional sampling) and ERT-estimated bulk conductivity are used to calculate heterogeneous mass transfer rate and immobile porosity fractions in a series of numerical column experiments. Copyright 2008 by the American Geophysical Union.
Iris Recognition Using Image Moments and k-Means Algorithm
Directory of Open Access Journals (Sweden)
Yaser Daanial Khan
2014-01-01
Full Text Available This paper presents a biometric technique for identification of a person using the iris image. The iris is first segmented from the acquired image of an eye using an edge detection algorithm. The disk shaped area of the iris is transformed into a rectangular form. Described moments are extracted from the grayscale image which yields a feature vector containing scale, rotation, and translation invariant moments. Images are clustered using the k-means algorithm and centroids for each cluster are computed. An arbitrary image is assumed to belong to the cluster whose centroid is the nearest to the feature vector in terms of Euclidean distance computed. The described model exhibits an accuracy of 98.5%.
Iris recognition using image moments and k-means algorithm.
Khan, Yaser Daanial; Khan, Sher Afzal; Ahmad, Farooq; Islam, Saeed
2014-01-01
This paper presents a biometric technique for identification of a person using the iris image. The iris is first segmented from the acquired image of an eye using an edge detection algorithm. The disk shaped area of the iris is transformed into a rectangular form. Described moments are extracted from the grayscale image which yields a feature vector containing scale, rotation, and translation invariant moments. Images are clustered using the k-means algorithm and centroids for each cluster are computed. An arbitrary image is assumed to belong to the cluster whose centroid is the nearest to the feature vector in terms of Euclidean distance computed. The described model exhibits an accuracy of 98.5%.
Moment of inertia of liquid in a tank
Directory of Open Access Journals (Sweden)
Gyeong Joong Lee
2014-03-01
Full Text Available In this study, the inertial properties of fully filled liquid in a tank were studied based on the potential theory. The analytic solution was obtained for the rectangular tank, and the numerical solutions using Green's 2nd identity were obtained for other shapes. The inertia of liquid behaves like solid in recti-linear acceleration. But under rotational acceleration, the moment of inertia of liquid becomes small compared to that of solid. The shapes of tank investigated in this study were ellipse, rectangle, hexagon, and octagon with various aspect ratios. The numerical solutions were compared with analytic solution, and an ad hoc semi-analytical approximate formula is proposed herein and this formula gives very good predictions for the moment of inertia of the liquid in a tank of several different geometrical shapes. The results of this study will be useful in analyzing of the motion of LNG/LPG tanker, liquid cargo ship, and damaged ship.
Magnetic resonance signal moment determination using the Earth's magnetic field
Fridjonsson, Einar Orn
2015-03-01
We demonstrate a method to manipulate magnetic resonance data such that the moments of the signal spatial distribution are readily accessible. Usually, magnetic resonance imaging relies on data acquired in so-called k-space which is subsequently Fourier transformed to render an image. Here, via analysis of the complex signal in the vicinity of the centre of k-space we are able to access the first three moments of the signal spatial distribution, ultimately in multiple directions. This is demonstrated for biofouling of a reverse osmosis (RO) membrane module, rendering unique information and an early warning of the onset of fouling. The analysis is particularly applicable for the use of mobile magnetic resonance spectrometers; here we demonstrate it using an Earth\\'s magnetic field system.
Measurement of nuclear moments and radii by collinear laser spectroscopy
Geithner, W R; Lievens, P; Kotrotsios, G; Silverans, R; Kappertz, S
2002-01-01
%IS304 %title\\\\ \\\\Collinear laser spectroscopy on a fast beam has proven to be a widely applicable and very efficient tool for measurements of changes in mean square nuclear charge radii, nuclear spins, magnetic dipole and electric quadrupole moments. Recent developments of extremely sensitive non-optical detection schemes enabled for some elements the extension of the measurements towards the very short-lived isotopes in the far wings of the ISOLDE production curves. The gain in sensitivity opens up new perspectives, particularly for measurements on lighter nuclei whose ground-state properties can be interpreted by large scale microscopic calculations instead of the more phenomenologic models used for heavier nuclei.\\\\ \\\\ For the sequence of argon isotopes $^{32-40}$Ar and $^{46}$Ar isotope shifts and nuclear moments were measured by optical pumping followed by state selective collisional ionization and detection of the $\\beta$-decay. Similarly, the low-background $\\alpha$-detection was used to extend earlie...
Gate-dependent orbital magnetic moments in carbon nanotubes
DEFF Research Database (Denmark)
Jespersen, Thomas Sand; Grove-Rasmussen, Kasper; Flensberg, Karsten
2011-01-01
We investigate how the orbital magnetic moments of electron and hole states in a carbon nanotube quantum dot depend on the number of carriers on the dot. Low temperature transport measurements are carried out in a setup where the device can be rotated in an applied magnetic field, thus enabling...... accurate alignment with the nanotube axis. The field dependence of the level structure is measured by excited state spectroscopy and excellent correspondence with a single-particle calculation is found. In agreement with band structure calculations we find a decrease of the orbital magnetic moment...... with increasing electron or hole occupation of the dot, with a scale given by the band gap of the nanotube....
Rotation Detection Using the Precession of Molecular Electric Dipole Moment
Ke, Yi; Deng, Xiao-Bing; Hu, Zhong-Kun
2017-11-01
We present a method to detect the rotation by using the precession of molecular electric dipole moment in a static electric field. The molecular electric dipole moments are polarized under the static electric field and a nonzero electric polarization vector emerges in the molecular gas. A resonant radio-frequency pulse electric field is applied to realize a 90° flip of the electric polarization vector of a particular rotational state. After the pulse electric field, the electric polarization vector precesses under the static electric field. The rotation induces a shift in the precession frequency which is measured to deduce the angular velocity of the rotation. The fundamental sensitivity limit of this method is estimated. This work is only a proposal and does not involve experimental results.
Nucleon electric dipole moments in high-scale supersymmetric models
Energy Technology Data Exchange (ETDEWEB)
Hisano, Junji [Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI),Nagoya University,Nagoya 464-8602 (Japan); Department of Physics, Nagoya University,Nagoya 464-8602 (Japan); Kavli IPMU (WPI), UTIAS, University of Tokyo,Kashiwa, Chiba 277-8584 (Japan); Kobayashi, Daiki; Kuramoto, Wataru; Kuwahara, Takumi [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan)
2015-11-12
The electric dipole moments (EDMs) of electron and nucleons are promising probes of the new physics. In generic high-scale supersymmetric (SUSY) scenarios such as models based on mixture of the anomaly and gauge mediations, gluino has an additional contribution to the nucleon EDMs. In this paper, we studied the effect of the CP-violating gluon Weinberg operator induced by the gluino chromoelectric dipole moment in the high-scale SUSY scenarios, and we evaluated the nucleon and electron EDMs in the scenarios. We found that in the generic high-scale SUSY models, the nucleon EDMs may receive the sizable contribution from the Weinberg operator. Thus, it is important to compare the nucleon EDMs with the electron one in order to discriminate among the high-scale SUSY models.
Molecular electric moments calculated by using natural orbital functional theory
Mitxelena, Ion
2016-01-01
The molecular electric dipole, quadrupole and octupole moments of a selected set of 21 spin-compensated molecules are determined employing the extended version of the Piris natural orbital functional 6 (PNOF6), using the triple-$\\zeta$ Gaussian basis set with polarization functions developed by Sadlej, at the experimental geometries. The performance of the PNOF6 is established by carrying out a statistical analysis of the mean absolute errors with respect to the experiment. The calculated PNOF6 electric moments agree satisfactorily with the corresponding experimental data, and are in good agreement with the values obtained by accurate ab initio methods, namely, the coupled-cluster single and doubles (CCSD) and multi-reference single and double excitation configuration interaction (MRSD-CI) methods.
Comparison of exit time moment spectra for extrinsic metric balls
DEFF Research Database (Denmark)
Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente
2012-01-01
We prove explicit upper and lower bounds for the $L^1$-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds $P^m$ in ambient Riemannian spaces $N^n$. We assume that $P$ and $N$ both have controlled radial curvatures (mean curvature and sectional curvature......, respectively) as viewed from a pole in $N$. The bounds for the exit moment spectra are given in terms of the corresponding spectra for geodesic metric balls in suitably warped product model spaces. The bounds are sharp in the sense that equalities are obtained in characteristic cases. As a corollary we also...... obtain new intrinsic comparison results for the exit time spectra for metric balls in the ambient manifolds $N^n$ themselves....
Anomalous superconductivity in the tJ model; moment approach
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Rodriguez-Nunez, J.J.
1997-01-01
By extending the moment approach of Nolting (Z, Phys, 225 (1972) 25) in the superconducting phase, we have constructed the one-particle spectral functions (diagonal and off-diagonal) for the tJ model in any dimensions. We propose that both the diagonal and the off-diagonal spectral functions...... Hartree shift which in the end result enlarges the bandwidth of the free carriers allowing us to take relative high values of J/t and allowing superconductivity to live in the T-c-rho phase diagram, in agreement with numerical calculations in a cluster, We have calculated the static spin susceptibility......, chi(T), and the specific heat, C-v(T), within the moment approach. We find that all the relevant physical quantities show the signature of superconductivity at T-c in the form of kinks (anomalous behavior) or jumps, for low density, in agreement with recent published literature, showing a generic...
Magnetic charge and moment dynamics in artificial kagome spin ice
Farhan, A.; Derlet, P. M.; Anghinolfi, L.; Kleibert, A.; Heyderman, L. J.
2017-08-01
Spin ice materials represent an intriguing class of frustrated magnetic systems which, through their geometry, admit an exponential number of approximately degenerate configurations. In this paper, the relaxation properties of a thermally active artificial kagome spin ice system are studied. Through application of an external magnetic field, an out-of-equilibrium vertex charge ordered configuration is selected and relaxed under approximate zero-field conditions. Using x-ray photo-emission electron microscopy, the magnetic moment and vertex charge degrees of freedom are followed in space and time, revealing different dynamics to that seen in past athermal equilibration protocols, and a relaxation which is well described by a point-dipolar model system. Furthermore the charge correlations are found to relax with a time scale several times smaller than that of the moment correlations.
Investigation of Asphaltene Precipitation at Elevated Temperature
DEFF Research Database (Denmark)
Andersen, Simon Ivar; Lindeloff, Niels; Stenby, Erling Halfdan
1998-01-01
In order to obtain quantitative data on the asphaltene precipitation induced by the addition of n-alkane (heptane) at temperatures above the normal boiling point of the precipitant, a high temperature/high pressure filtration apparatus has been constructed. Oil and alkane are mixed at the appropr......In order to obtain quantitative data on the asphaltene precipitation induced by the addition of n-alkane (heptane) at temperatures above the normal boiling point of the precipitant, a high temperature/high pressure filtration apparatus has been constructed. Oil and alkane are mixed...... in the extracted fraction, hence there is no room for stirring. The equipment as well as solutions to some of the problems are presented along with precipitation data from 40 to 200 degrees C. The asphaltenes separated are analyzed using FT-ir. The filtrate containing the maltenes was cooled to room temperature...
Distributionally Robust Joint Chance Constrained Problem under Moment Uncertainty
Directory of Open Access Journals (Sweden)
Ke-wei Ding
2014-01-01
Full Text Available We discuss and develop the convex approximation for robust joint chance constraints under uncertainty of first- and second-order moments. Robust chance constraints are approximated by Worst-Case CVaR constraints which can be reformulated by a semidefinite programming. Then the chance constrained problem can be presented as semidefinite programming. We also find that the approximation for robust joint chance constraints has an equivalent individual quadratic approximation form.
Electric dipole moments with and beyond flavor invariants
Christopher Smith; Selim Touati
2017-01-01
In this paper, the flavor structure of quark and lepton electric dipole moments in the SM and beyond is investigated using tools inspired from Minimal Flavor Violation. While Jarlskog-like flavor invariants are adequate for estimating CP-violation from closed fermion loops, non-invariant structures arise from rainbow-like processes. Our goal is to systematically construct these latter flavor structures in the quark and lepton sectors, assuming different mechanisms for generating neutrino mass...
Electric dipole moments with and beyond flavor invariants
Smith, Christopher; Touati, Selim
2017-01-01
In this paper, the flavor structure of quark and lepton electric dipole moments in the SM and beyond is investigated using tools inspired from Minimal Flavor Violation. While Jarlskog-like flavor invariants are adequate for estimating CP -violation from closed fermion loops, non-invariant structures arise from rainbow-like processes. Our goal is to systematically construct these latter flavor structures in the quark and lepton sectors, assuming different mechanisms for generating neutrino mas...
Influence of Whipping on Long term Vertical Bending Moment
DEFF Research Database (Denmark)
Baarholm, G. S.; Jensen, Jørgen Juncher
2004-01-01
approach. Effect of whipping is included by assuming that the whipping and wave induced response are independent, but the effect of correlation of the long term extreme value is also studied. Numerical calculations are performed using a nonlinear, hydroelastic strip theory as suggested by (Xia et al 1998......). Results are presented for the S-175 container ship, (15th & 16th ITTC Seakeeping Committee 1983). The analysis shoes that whipping increases the vertical bending moment and that the correlation is significant...
Rotation invariants from Gaussian-Hermite moments of color images
Czech Academy of Sciences Publication Activity Database
Yang, B.; Suk, Tomáš; Flusser, Jan; Shi, Z.; Chen, X.
2018-01-01
Roč. 143, č. 1 (2018), s. 282-291 ISSN 0165-1684 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Color images * Object recognition * Rotation invariants * Gaussian–Hermite moments * Joint invariants Subject RIV: JD - Computer Applications, Robotics Impact factor: 3.110, year: 2016 http:// library .utia.cas.cz/separaty/2017/ZOI/suk-0479748.pdf
Partial Generalized Probability Weighted Moments for Exponentiated Exponential Distribution
Directory of Open Access Journals (Sweden)
Neema Mohamed El Haroun
2015-09-01
Full Text Available The generalized probability weighted moments are widely used in hydrology for estimating parameters of flood distributions from complete sample. The method of partial generalized probability weighted moments was used to estimate the parameters of distributions from censored sample. This article offers new method called partial generalized probability weighted moments (PGPWMs for the analysis of censored data. The method of PGPWMs is an extended class from partial generalized probability weighted moments. To illustrate the new method, estimation of the unknown parameters from exponentiated exponential distribution based on doubly censored sample is considered. PGPWMs estimators for right and left censored samples are obtained as special cases. Simulation study is conducted to investigate performance of estimates for exponentiated exponential distribution. Comparison between estimators is made through simulation via their biases and mean square errors. An illustration with real data is provided. Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"جدول عادي"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;}
Estimation of the Handwritten Text Skew Based on Binary Moments
D. Brodić, Z. Milivojević
2012-01-01
Binary moments represent one of the methods for the text skew estimation in binary images. It has been used widely for the skew identification of the printed text. However, the handwritten text consists of text objects, which are characterized with different skews. Hence, the method should be adapted for the handwritten text. This is achieved with the image splitting into separate text objects made by the bounding boxes. Obtained text objects represent the isolated binary objects. The applica...
On moments of the integrated exponential Brownian motion
Caravelli, Francesco; Mansour, Toufik; Sindoni, Lorenzo; Severini, Simone
2016-07-01
We present new exact expressions for a class of moments of the geometric Brownian motion in terms of determinants, obtained using a recurrence relation and combinatorial arguments for the case of a Itô's Wiener process. We then apply the obtained exact formulas to computing averages of the solution of the logistic stochastic differential equation via a series expansion, and compare the results to the solution obtained via Monte Carlo.
Rayleigh-Ritz variation method and connected-moments expansions
Energy Technology Data Exchange (ETDEWEB)
Amore, Paolo [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Colima (Mexico); Fernandez, Francisco M [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Blvd 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)], E-mail: fernande@quimica.unlp.edu.ar
2009-11-15
We compare the connected-moments expansion (CMX) with the Rayleigh-Ritz variational method in the Krylov space (RRK). As a benchmark model we choose the same two-dimensional anharmonic oscillator already treated earlier by means of the CMX. Our results show that the RRK converges more smoothly than the CMX. We also discuss the fact that the CMX is size consistent while the RRK is not.
Condensation of Neutral Vector Bosons with Magnetic Moment
Angulo, Gretel Quintero; Martínez, Aurora Pérez; Rojas, Hugo Pérez
We study the equation of motion of neutral vector bosons bearing a magnetic moment (MM). The effective rest mass of vector bosons is a decreasing function of the magnetic field intensity. Consequently a diffuse condensation of the bosons appears below a critical value of the field. For typical values of densities and magnetic fields the magnetization is positive and the neutral boson system can maintain a magnetic field self-consistently. A discussion of the relevance in astrophysics is presented.
Modifying and Accelerating the Method of Moments Calculation
René Harťanský; Viktor Smieško; Michal Rafaj
2017-01-01
This manuscript deals with optimizing the numerical method called the method of moments (MoM). This method is widely utilized for field computation of 3D structures. MoM is exploited in hydraulics as well as in the electromagnetic field theory. Emphasis is put on minimizing calculations necessary for constructing a system of linear equations exploiting symmetry or similarity of elements of geometric structure. The manuscript also contains a comparison of computing times using standard MoM and...
Prediction of conformationally dependent atomic multipole moments in carbohydrates.
Cardamone, Salvatore; Popelier, Paul L A
2015-12-15
The conformational flexibility of carbohydrates is challenging within the field of computational chemistry. This flexibility causes the electron density to change, which leads to fluctuating atomic multipole moments. Quantum Chemical Topology (QCT) allows for the partitioning of an "atom in a molecule," thus localizing electron density to finite atomic domains, which permits the unambiguous evaluation of atomic multipole moments. By selecting an ensemble of physically realistic conformers of a chemical system, one evaluates the various multipole moments at defined points in configuration space. The subsequent implementation of the machine learning method kriging delivers the evaluation of an analytical function, which smoothly interpolates between these points. This allows for the prediction of atomic multipole moments at new points in conformational space, not trained for but within prediction range. In this work, we demonstrate that the carbohydrates erythrose and threose are amenable to the above methodology. We investigate how kriging models respond when the training ensemble incorporating multiple energy minima and their environment in conformational space. Additionally, we evaluate the gains in predictive capacity of our models as the size of the training ensemble increases. We believe this approach to be entirely novel within the field of carbohydrates. For a modest training set size of 600, more than 90% of the external test configurations have an error in the total (predicted) electrostatic energy (relative to ab initio) of maximum 1 kJ mol(-1) for open chains and just over 90% an error of maximum 4 kJ mol(-1) for rings. © 2015 Wiley Periodicals, Inc.
Improving Bending Moment Measurements on Wind Turbine Blades
Energy Technology Data Exchange (ETDEWEB)
Post, Nathan L.
2016-03-15
Full-scale fatigue testing of wind turbine blades is conducted using resonance test techniques where the blade plus additional masses is excited at its first resonance frequency to achieve the target loading amplitude. Because there is not a direct relationship between the force applied by an actuator and the bending moment, the blade is instrumented with strain gauges that are calibrated under static loading conditions to determine the sensitivity or relationship between strain and applied moment. Then, during dynamic loading the applied moment is calculated using the strain response of the structure. A similar procedure is also used in the field to measure in-service loads on turbine blades. Because wind turbine blades are complex twisted structures and the deflections are large, there is often significant cross-talk coupling in the sensitivity of strain gauges placed on the structure. Recent work has shown that a sensitivity matrix with nonzero cross terms must be employed to find constant results when a blade is subjected to both flap and lead-lag loading. However, even under controlled laboratory conditions, potential for errors of 3 percent or more in the measured moment exist when using the typical cross-talk matrix approach due to neglecting the influence of large deformations and torsion. This is particularly critical when considering a biaxial load as would be applied on the turbine or during a biaxial fatigue test. This presentation describes these results demonstrating errors made when performing current loads measurement practices on wind turbine blades in the lab and evaluating potential improvements using enhanced cross-talk matrix approaches and calibration procedures.
Probabilistic Precipitation Estimation with a Satellite Product
Directory of Open Access Journals (Sweden)
Nir Y. Krakauer
2015-04-01
Full Text Available Satellite-based precipitation products have been shown to represent precipitation well over Nepal at monthly resolution, compared to ground-based stations. Here, we extend our analysis to the daily and subdaily timescales, which are relevant for mapping the hazards caused by storms as well as drought. We compared the Tropical Rainfall Measuring Mission (TRMM Multi-satellite Precipitation Analysis (TMPA 3B42RT product with individual stations and with the gridded APHRODITE product to evaluate its ability to retrieve different precipitation intensities. We find that 3B42RT, which is freely available in near real time, has reasonable correspondence with ground-based precipitation products on a daily timescale; rank correlation coefficients approach 0.6, almost as high as the retrospectively calibrated TMPA 3B42 product. We also find that higher-quality ground and satellite precipitation observations improve the correspondence between the two on the daily timescale, suggesting opportunities for improvement in satellite-based monitoring technology. Correlation of 3B42RT and 3B42 with station observations is lower on subdaily timescales, although the mean diurnal cycle of precipitation is roughly correct. We develop a probabilistic precipitation monitoring methodology that uses previous observations (climatology as well as 3B42RT as input to generate daily precipitation accumulation probability distributions at each 0.25° x 0.25° grid cell in Nepal and surrounding areas. We quantify the information gain associated with using 3B42RT in the probabilistic model instead of relying only on climatology and show that the quantitative precipitation estimates produced by this model are well calibrated compared to APHRODITE.
Uncertainty in determining extreme precipitation thresholds
Liu, Bingjun; Chen, Junfan; Chen, Xiaohong; Lian, Yanqing; Wu, Lili
2013-10-01
Extreme precipitation events are rare and occur mostly on a relatively small and local scale, which makes it difficult to set the thresholds for extreme precipitations in a large basin. Based on the long term daily precipitation data from 62 observation stations in the Pearl River Basin, this study has assessed the applicability of the non-parametric, parametric, and the detrended fluctuation analysis (DFA) methods in determining extreme precipitation threshold (EPT) and the certainty to EPTs from each method. Analyses from this study show the non-parametric absolute critical value method is easy to use, but unable to reflect the difference of spatial rainfall distribution. The non-parametric percentile method can account for the spatial distribution feature of precipitation, but the problem with this method is that the threshold value is sensitive to the size of rainfall data series and is subjected to the selection of a percentile thus make it difficult to determine reasonable threshold values for a large basin. The parametric method can provide the most apt description of extreme precipitations by fitting extreme precipitation distributions with probability distribution functions; however, selections of probability distribution functions, the goodness-of-fit tests, and the size of the rainfall data series can greatly affect the fitting accuracy. In contrast to the non-parametric and the parametric methods which are unable to provide information for EPTs with certainty, the DFA method although involving complicated computational processes has proven to be the most appropriate method that is able to provide a unique set of EPTs for a large basin with uneven spatio-temporal precipitation distribution. The consistency between the spatial distribution of DFA-based thresholds with the annual average precipitation, the coefficient of variation (CV), and the coefficient of skewness (CS) for the daily precipitation further proves that EPTs determined by the DFA method
Validity conditions for moment closure approximations in stochastic chemical kinetics.
Schnoerr, David; Sanguinetti, Guido; Grima, Ramon
2014-08-28
Approximations based on moment-closure (MA) are commonly used to obtain estimates of the mean molecule numbers and of the variance of fluctuations in the number of molecules of chemical systems. The advantage of this approach is that it can be far less computationally expensive than exact stochastic simulations of the chemical master equation. Here, we numerically study the conditions under which the MA equations yield results reflecting the true stochastic dynamics of the system. We show that for bistable and oscillatory chemical systems with deterministic initial conditions, the solution of the MA equations can be interpreted as a valid approximation to the true moments of the chemical master equation, only when the steady-state mean molecule numbers obtained from the chemical master equation fall within a certain finite range. The same validity criterion for monostable systems implies that the steady-state mean molecule numbers obtained from the chemical master equation must be above a certain threshold. For mean molecule numbers outside of this range of validity, the MA equations lead to either qualitatively wrong oscillatory dynamics or to unphysical predictions such as negative variances in the molecule numbers or multiple steady-state moments of the stationary distribution as the initial conditions are varied. Our results clarify the range of validity of the MA approach and show that pitfalls in the interpretation of the results can only be overcome through the systematic comparison of the solutions of the MA equations of a certain order with those of higher orders.
Multivariate moment closure techniques for stochastic kinetic models
Energy Technology Data Exchange (ETDEWEB)
Lakatos, Eszter, E-mail: e.lakatos13@imperial.ac.uk; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H., E-mail: m.stumpf@imperial.ac.uk [Department of Life Sciences, Centre for Integrative Systems Biology and Bioinformatics, Imperial College London, London SW7 2AZ (United Kingdom)
2015-09-07
Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs.
Search for anomalous weak dipole moments of the $\\tau$ lepton
Heister, A; Barate, R; De Bonis, I; Décamp, D; Goy, C; Lees, J P; Merle, E; Minard, M N; Pietrzyk, B; Bravo, S; Casado, M P; Chmeissani, M; Crespo, J M; Fernández, E; Fernández-Bosman, M; Garrido, L; Martínez, M; Pacheco, A; Ruiz, H; Colaleo, A; Creanza, D; De Palma, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Azzurri, P; Buchmüller, O L; Cattaneo, M; Cerutti, F; Clerbaux, B; Drevermann, H; Forty, R W; Frank, M; Gianotti, F; Hansen, J B; Harvey, J; Hutchcroft, D E; Janot, P; Jost, B; Kado, M; Mato, P; Moutoussi, A; Ranjard, F; Rolandi, Luigi; Schlatter, W D; Schneider, O; Sguazzoni, G; Tejessy, W; Teubert, F; Valassi, Andrea; Videau, I; Ward, J; Badaud, F; Falvard, A; Gay, P; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Markou, C; Simopoulou, Errietta; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Rougé, A; Rumpf, M; Swynghedauw, M; Verderi, M; Videau, H L; Ciulli, V; Focardi, E; Parrini, G; Antonelli, A; Antonelli, M; Bencivenni, G; Bossi, F; Capon, G; Chiarella, V; Laurelli, P; Mannocchi, G; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Lynch, J G; Negus, P; O'Shea, V; Raine, C; Thompson, A S; Wasserbaech, S R; Cavanaugh, R J; Geweniger, C; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Stenzel, H; Tittel, K; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, P J; Girone, M; Marinelli, N; Sedgbeer, J K; Thompson, J C; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bouhova-Thacker, E; Bowdery, C K; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Pearson, M R; Robertson, N A; Jakobs, K; Kleinknecht, K; Renk, B; Sander, H G; Wachsmuth, H W; Zeitnitz, C; Bonissent, A; Coyle, P; Leroy, O; Payre, P; Rousseau, D; Talby, M; Ragusa, F; David, A; Dietl, H; Ganis, G; Hüttmann, K; Lütjens, G; Männer, W; Moser, H G; Settles, Ronald; Wolf, G; Boucrot, J; Callot, O; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacholkowska, A; Lefrançois, J; Veillet, J J; Yuan, C; Bagliesi, G; Boccali, T; Foà, L; Giammanco, A; Giassi, A; Ligabue, F; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Tenchini, Roberto; Venturi, A; Verdini, P G; Blair, G A; Cowan, G; Green, M G; Medcalf, T; Misiejuk, A; Strong, J A; Teixeira-Dias, P; Clifft, R W; Edgecock, T R; Norton, P R; Tomalin, I R; Bloch-Devaux, B; Colas, P; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Schuller, J P; Vallage, B; Konstantinidis, N P; Litke, A M; Taylor, G; Booth, C N; Cartwright, S L; Combley, F; Lehto, M H; Thompson, L F; Böhrer, A; Brandt, S; Grupen, Claus; Ngac, A; Prange, G; Giannini, G; Rothberg, J E; Armstrong, S R; Berkelman, K; Cranmer, K; Ferguson, D P S; Gao, Y; Gonzáles, S; Hayes, O J; Hu, H; Jin, S; Kile, J; McNamara, P A; Nielsen, J; Pan, Y B; Von Wimmersperg-Töller, J H; Wiedenmann, W; Wu, J; Wu Sau Lan; Wu, X; Zobernig, G; Dissertori, G
2003-01-01
The anomalous weak dipole moments of the $\\tau$ lepton are measured in a data sample collected by ALEPH from 1990 to 1995 corresponding to an integrated luminosity of 155~pb$^{-1}$. Tau leptons produced in the reaction $e^+ e^- \\rightarrow \\tau^+ \\tau^-$ at energies close to the ${\\rm Z}$ mass are studied using their semileptonic decays to $\\pi$, $\\rho$, $a_1 \\rightarrow \\pi 2\\pi^0$ or $a_1 \\rightarrow 3 \\pi$. The real and imaginary components of both the anomalous weak magnetic dipole moment and the CP-violating anomalous weak electric dipole moment, $ {\\rm Re}\\,\\mu_{\\tau}$, ${\\rm Im}\\,\\mu_{\\tau}$, ${\\rm Re}\\,d_{\\tau}$ and ${\\rm Im}\\,d_{\\tau}$, are measured simultaneously by means of a likelihood fit built from the full differential cross section. No evidence of new physics is found. The following bounds are obtained (95\\% CL): $|{\\rm Re}\\, \\mu_{\\tau} | < 1.14 \\times 10^{-3}$, $|{\\rm Im}\\, \\mu_{\\tau} | < 2.65 \\times 10^{-3}$, $|{\\rm Re}\\, d_{\\tau} | < 0.91 \\times 10^{-3}$, and $|{\\rm Im}\\, d_{\\tau} ...
Quantum oscillations of the magnetic moment of graphene and graphite
Petkovic, Ivana; Lollo, Anthony; Wang, Ke; Kim, Philip; Harris, Jack
Quantum oscillations of the magnetic moment, so called de Haas - van Alphen (dHvA) oscillations, are a powerful tool for the investigation of the Fermi surface. In graphene with a fixed carrier density, the magnetic moment is predicted to oscillate as function of increasing perpendicular field B every time the uppermost Landau level empties out, yielding the characteristic 1/B dependence. To date, it has been challenging to measure the equilibrium magnetic moment of isolated samples of graphene. In graphite a more complex oscillation sequence is observed, due to its complicated Fermi surface with both electron and hole carriers. Historically graphite was one of the first materials in which dHvA oscillations were studied, but recently interest was revived due to an observation of carriers with relativistic dynamics. We have used cantilever torque magnetometry to study diamagnetism and dHvA oscillations of isolated samples of graphene and graphite between 400 mK and 20 K. For graphite, we observe dHvA oscillations which are used to study the composition and nature of carriers. For graphene, we discuss the results in relation to relativistic dispersion and disorder.
Magnetic moments of K isomers as indicators of octupole collectivity
Energy Technology Data Exchange (ETDEWEB)
Minkov, N. [Bulgarian Academy of Sciences, Institute of Nuclear Research and Nuclear Energy, Sofia (Bulgaria); University of Surrey, Department of Physics, Guildford (United Kingdom); Walker, P.M. [University of Surrey, Department of Physics, Guildford (United Kingdom); CERN, Geneva (Switzerland)
2012-06-15
The relation between the quadrupole-octupole deformation and the structure of high-K isomers in heavy even-even nuclei is studied through a reflection asymmetric deformed shell model including a BCS procedure with constant pairing interaction. Two-quasiparticle states with K{sup {pi}} = 4 {sup -}, 5 {sup -}, 6 {sup -}, 6 {sup +} and 7 {sup -} are considered in the region of actinide nuclei (U, Pu and Cm) and rare-earth nuclei (Nd, Sm and Gd). The behaviour of two-quasiparticle energies and magnetic dipole moments of these configurations is examined over a wide range in the plane of quadrupole and octupole deformations ({beta}{sub 2} and {beta}{sub 3}). In all considered actinide nuclei, the calculations show that there is pronounced sensitivity of the magnetic moments to the octupole deformation. In the rare-earth nuclei, the calculations for {sup 154,} {sup 156}Gd show stronger sensitivity of the magnetic moment to the octupole deformation than in the other considered cases. (orig.)
Variational-moment method for computing magnetohydrodynamic equilibria
Energy Technology Data Exchange (ETDEWEB)
Lao, L.L.
1983-08-01
A fast yet accurate method to compute magnetohydrodynamic equilibria is provided by the variational-moment method, which is similar to the classical Rayleigh-Ritz-Galerkin approximation. The equilibrium solution sought is decomposed into a spectral representation. The partial differential equations describing the equilibrium are then recast into their equivalent variational form and systematically reduced to an optimum finite set of coupled ordinary differential equations. An appropriate spectral decomposition can make the series representing the solution coverge rapidly and hence substantially reduces the amount of computational time involved. The moment method was developed first to compute fixed-boundary inverse equilibria in axisymmetric toroidal geometry, and was demonstrated to be both efficient and accurate. The method since has been generalized to calculate free-boundary axisymmetric equilibria, to include toroidal plasma rotation and pressure anisotropy, and to treat three-dimensional toroidal geometry. In all these formulations, the flux surfaces are assumed to be smooth and nested so that the solutions can be decomposed in Fourier series in inverse coordinates. These recent developments and the advantages and limitations of the moment method are reviewed. The use of alternate coordinates for decomposition is discussed.
Explicit expression for effective moment of inertia of RC beams
Directory of Open Access Journals (Sweden)
K.A. Patel
Full Text Available AbstractDeflection is an important design parameter for structures subjected to service load. This paper provides an explicit expression for effective moment of inertia considering cracking, for uniformly distributed loaded reinforced concrete (RC beams. The proposed explicit expression can be used for rapid prediction of short-term deflection at service load. The explicit expression has been obtained from the trained neural network considering concrete cracking, tension stiffening and entire practical range of reinforcement. Three significant structural parameters have been identified that govern the change in effective moment of inertia and therefore deflection. These three parameters are chosen as inputs to train neural network. The training data sets for neural network are generated using finite element software ABAQUS. The explicit expression has been validated for a number of simply supported and continuous beams and it is shown that the predicted deflections have reasonable accuracy for practical purpose. A sensitivity analysis has been performed, which indicates substantial dependence of effective moment of inertia on the selected input parameters.
Multivariate moment closure techniques for stochastic kinetic models
Lakatos, Eszter; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H.
2015-09-01
Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs.
Extracting the Omega- electric quadrupole moment from lattice QCD data
Energy Technology Data Exchange (ETDEWEB)
G. Ramalho, M.T. Pena
2011-03-01
The Omega- has an extremely long lifetime, and is the most stable of the baryons with spin 3/2. Therefore the Omega- magnetic moment is very accurately known. Nevertheless, its electric quadrupole moment was never measured, although estimates exist in different formalisms. In principle, lattice QCD simulations provide at present the most appropriate way to estimate the Omega- form factors, as function of the square of the transferred four-momentum, Q2, since it describes baryon systems at the physical mass for the strange quark. However, lattice QCD form factors, and in particular GE2, are determined at finite Q2 only, and the extraction of the electric quadrupole moment, Q_Omega= GE2(0) e/(2 M_Omega), involves an extrapolation of the numerical lattice results. In this work we reproduce the lattice QCD data with a covariant spectator quark model for Omega- which includes a mixture of S and two D states for the relative quark-diquark motion. Once the model is calibrated, it is used to determine Q_Omega. Our prediction is Q_Omega= (0.96 +/- 0.02)*10^(-2) efm2 [GE2(0)=0.680 +/- 0.012].
Weibull distribution and the multiplicity moments in p p (p p¯) collisions
Pandey, Ashutosh Kumar; Sett, Priyanka; Dash, Sadhana
2017-10-01
A higher moment analysis of multiplicity distribution is performed using the Weibull description of particle production in p p (p p ¯) collisions at Super Proton Synchrotron (SPS) and LHC energies. The calculated normalized moments and factorial moments of Weibull distribution are compared to the measured data. The calculated Weibull moments are found to be in good agreement with the measured higher moments (up to fifth order) reproducing the observed breaking of Koba, Nielsen, and Olesen scaling in the data. The moments for p p collisions at √{s }=13 TeV are also predicted.
Demissie, Yonas; Dejene Demissie, Teferi; D'Odorico, Paolo; Sharma, Rishi
2013-04-01
Five years of the Tropical Rainfall Measuring Mission (TRMM) 2A25 radar reflectivity profiles and derived surface rain rates are used to describe the vertical structure of precipitation systems in boreal and austral summer rainy seasons in Africa. The continent is divided into several climatologically rather homogenous regions and those regions are characterized and contrasted. To place the composite reflectivity profiles in context, they are also contrasted against TRMM 2A25 observations over the Amazon. Precipitation systems tend to be deeper and more intense in all of tropical Africa than in the Amazon, and shallow warm-rain events are less common. Storms, in all African regions, are characterized by high echo tops, high hydro-meteor loading aloft, little indication of a radar bright band maximum at the freezing level, and evidence for low-level evaporation. The diurnal modulation is regionally variable. The amplitude of the diurnal cycle of the mean echo top height decreases from the arid margins of the zenithal rain region toward the equatorial region, and is smallest in the Amazon. A secondary predawn (0000-0600 LT) maximum occurs in the Congo, in terms of rainfall frequency, rainfall intensity, and echo tops. The difference between all African regions and the Amazon, and the relatively smaller differences between regions in Africa, can be understood in terms of the climatological humidity, CAPE, and low-level shear values.
Ginzburg, Irina
2017-01-01
The effect of the heterogeneity in the soil structure or the nonuniformity of the velocity field on the modeled resident time distribution (RTD) and breakthrough curves is quantified by their moments. While the first moment provides the effective velocity, the second moment is related to the longitudinal dispersion coefficient (kT) in the developed Taylor regime; the third and fourth moments are characterized by their normalized values skewness (Sk) and kurtosis (Ku), respectively. The purpose of this investigation is to examine the role of the truncation corrections of the numerical scheme in kT, Sk, and Ku because of their interference with the second moment, in the form of the numerical dispersion, and in the higher-order moments, by their definition. Our symbolic procedure is based on the recently proposed extended method of moments (EMM). Originally, the EMM restores any-order physical moments of the RTD or averaged distributions assuming that the solute concentration obeys the advection-diffusion equation in multidimensional steady-state velocity field, in streamwise-periodic heterogeneous structure. In our work, the EMM is generalized to the fourth-order-accurate apparent mass-conservation equation in two- and three-dimensional duct flows. The method looks for the solution of the transport equation as the product of a long harmonic wave and a spatially periodic oscillating component; the moments of the given numerical scheme are derived from a chain of the steady-state fourth-order equations at a single cell. This mathematical technique is exemplified for the truncation terms of the two-relaxation-time lattice Boltzmann scheme, using plug and parabolic flow in straight channel and cylindrical capillary with the d2Q9 and d3Q15 discrete velocity sets as simple but illustrative examples. The derived symbolic dependencies can be readily extended for advection by another, Newtonian or non-Newtonian, flow profile in any-shape open-tabular conduits. It is
Simon, Patrick; Schneider, Peter
2017-08-01
In weak gravitational lensing, weighted quadrupole moments of the brightness profile in galaxy images are a common way to estimate gravitational shear. We have employed general adaptive moments (GLAM ) to study causes of shear bias on a fundamental level and for a practical definition of an image ellipticity. The GLAM ellipticity has useful properties for any chosen weight profile: the weighted ellipticity is identical to that of isophotes of elliptical images, and in absence of noise and pixellation it is always an unbiased estimator of reduced shear. We show that moment-based techniques, adaptive or unweighted, are similar to a model-based approach in the sense that they can be seen as imperfect fit of an elliptical profile to the image. Due to residuals in the fit, moment-based estimates of ellipticities are prone to underfitting bias when inferred from observed images. The estimation is fundamentally limited mainly by pixellation which destroys information on the original, pre-seeing image. We give an optimised estimator for the pre-seeing GLAM ellipticity and quantify its bias for noise-free images. To deal with images where pixel noise is prominent, we consider a Bayesian approach to infer GLAM ellipticity where, similar to the noise-free case, the ellipticity posterior can be inconsistent with the true ellipticity if we do not properly account for our ignorance about fit residuals. This underfitting bias, quantified in the paper, does not vary with the overall noise level but changes with the pre-seeing brightness profile and the correlation or heterogeneity of pixel noise over the image. Furthermore, when inferring a constant ellipticity or, more relevantly, constant shear from a source sample with a distribution of intrinsic properties (sizes, centroid positions, intrinsic shapes), an additional, now noise-dependent bias arises towards low signal-to-noise if incorrect prior densities for the intrinsic properties are used. We discuss the origin of this
Estimation of Probable Maximum Precipitation in Korea using a Regional Climate Model
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Jeonghoon Lee
2017-03-01
Full Text Available Extreme precipitation events have been extensively applied to the design of social infra structures. Thus, a method to more scientifically estimate the extreme event is required. This paper suggests a method to estimate the extreme precipitation in Korea using a regional climate model. First, several historical extreme events are identified and the most extreme event of Typhoon Rusa (2002 is selected. Second, the selected event is reconstructed through the Weather Research and Forecasting (WRF model, one of the Regional Climate Models (RCMs. Third, the reconstructed event is maximized by adjusting initial and boundary conditions. Finally, the Probable Maximum Precipitation (PMP is obtained. The WRF could successfully simulate the observed precipitation in terms of spatial and temporal distribution (R2 = 0.81. The combination of the WRF Single-Moment (WSM 6-class graupel scheme (of microphysics, the Betts-Miller-Janjic scheme (of cumulus parameterization and the Mellor-Yamada-Janjic Turbulent Kinetic Energy (TKE scheme (of planetary boundary layer was determined to be the best combination to reconstruct Typhoon Rusa. The estimated PMP (RCM_PMP was compared with the existing PMP. The RCM_PMP was generally in good agreement with the PMP. The suggested methodology is expected to provide assessments of the existing PMP and to provide a new alternative for estimating PMP.
Kobayashi, Toshiki; Singer, Madeline L; Orendurff, Michael S; Gao, Fan; Daly, Wayne K; Foreman, K Bo
2015-10-01
The adjustment of plantarflexion resistive moment of an articulated ankle-foot orthosis is considered important in patients post stroke, but the evidence is still limited. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments in patients post stroke. Gait analysis was performed on 10 subjects post stroke under four different plantarflexion resistive moment conditions using a newly designed articulated ankle-foot orthosis. Data were recorded using a Bertec split-belt instrumented treadmill in a 3-dimensional motion analysis laboratory. The ankle and knee sagittal joint angles and moments were significantly affected by the amount of plantarflexion resistive moment of the ankle-foot orthosis. Increasing the plantarflexion resistive moment of the ankle-foot orthosis induced significant decreases both in the peak ankle plantarflexion angle (Pdorsiflexion moment of the ankle joint (Pplantarflexion resistive moment of an articulated ankle-foot orthosis. A future study should be performed to clarify their relationship further so that the practitioners may be able to use these parameters as objective data to determine an optimal plantarflexion resistive moment of an articulated ankle-foot orthosis for improved orthotic care in individual patients. Copyright © 2015 Elsevier Ltd. All rights reserved.
Munchak, S. Joseph; Meneghini, Robert; Grecu, Mircea; Olson, William S.
2016-01-01
The Global Precipitation Measurement satellite's Microwave Imager (GMI) and Dual-frequency Precipitation Radar (DPR) are designed to provide the most accurate instantaneous precipitation estimates currently available from space. The GPM Combined Algorithm (CORRA) plays a key role in this process by retrieving precipitation profiles that are consistent with GMI and DPR measurements; therefore, it is desirable that the forward models in CORRA use the same geophysical input parameters. This study explores the feasibility of using internally consistent emissivity and surface backscatter cross-sectional (sigma(sub 0)) models for water surfaces in CORRA. An empirical model for DPR Ku and Ka sigma(sub 0) as a function of 10m wind speed and incidence angle is derived from GMI-only wind retrievals under clear-sky conditions. This allows for the sigma(sub 0) measurements, which are also influenced by path-integrated attenuation (PIA) from precipitation, to be used as input to CORRA and for wind speed to be retrieved as output. Comparisons to buoy data give a wind rmse of 3.7 m/s for Ku+GMI and 3.2 m/s for Ku+Ka+GMI retrievals under precipitation (compared to 1.3 m/s for clear-sky GMI-only), and there is a reduction in bias from GANAL background data (-10%) to the Ku+GMI (-3%) and Ku+Ka+GMI (-5%) retrievals. Ku+GMI retrievals of precipitation increase slightly in light (less than 1 mm/h) and decrease in moderate to heavy precipitation (greater than 1 mm/h). The Ku+Ka+GMI retrievals, being additionally constrained by the Ka reflectivity, increase only slightly in moderate and heavy precipitation at low wind speeds (less than 5 m/s) relative to retrievals using the surface reference estimate of PIA as input.
TEMPERATURE AND PRECIPITATION CHANGES IN TÂRGU-MURES (ROMANIA FROM PERIOD 1951-2010
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O.Rusz
2012-03-01
Full Text Available Temperature and precipitation changes in Târgu Mures (Romania from period 1951-2010. The analysis was made based upon meteorological data collected at Târgu Mures meteorological station (Romania, Mures county, lat. 46°32’N, lon. 24°32’E, elevation 308 m, between 1951 and 2010. Several climatic parameters were studied (for instance, annual and monthly mean temperature, maximum precipitation in 24 hours, number of summer days, etc. Detected inhomogeneities are not related to instrumental causes or geographical relocation. Positive and statistical significant trends (Mann-Kendall test are indicated for: mean annual temperatures, mean temperatures of warm months, average of the maximum and minimum temperatures (annual and warm months data, number of days with mean temperature between 20.1-25.0 °C, number of days with precipitation ≥0 mm, and for all parameters of precipitation of September. The sequential version of Mann-Kendall test show a beginning of a trend in 1956 in the case of mean temperature (at same, the two and three parts regression denote this year like a moment of change, years 1965 and 1992 in the case of annual amount of precipitation. CUSUM charts indicate occurs of changes points at 1988, 2005, 2009 (mean temperature respectively at 1989, 2004 (precipitation, and at 1968, 1992 (daily temperature range. Tendencies of overlapped time series reveal a more important increase at the end of period (mainly for mean temperature. The analysis with RClimDex show for 5 extreme climate indices a significant trend: positive for summer days, warm nights, warm spell duration indicator and negative for cold nights and cold days.
Baisden, W Troy; Keller, Elizabeth D; Van Hale, Robert; Frew, Russell D; Wassenaar, Leonard I
2016-01-01
Predictive understanding of precipitation δ(2)H and δ(18)O in New Zealand faces unique challenges, including high spatial variability in precipitation amounts, alternation between subtropical and sub-Antarctic precipitation sources, and a compressed latitudinal range of 34 to 47 °S. To map the precipitation isotope ratios across New Zealand, three years of integrated monthly precipitation samples were acquired from >50 stations. Conventional mean-annual precipitation δ(2)H and δ(18)O maps were produced by regressions using geographic and annual climate variables. Incomplete data and short-term variation in climate and precipitation sources limited the utility of this approach. We overcome these difficulties by calculating precipitation-weighted monthly climate parameters using national 5-km-gridded daily climate data. This data plus geographic variables were regressed to predict δ(2)H, δ(18)O, and d-excess at all sites. The procedure yields statistically-valid predictions of the isotope composition of precipitation (long-term average root mean square error (RMSE) for δ(18)O = 0.6 ‰; δ(2)H = 5.5 ‰); and monthly RMSE δ(18)O = 1.9 ‰, δ(2)H = 16 ‰. This approach has substantial benefits for studies that require the isotope composition of precipitation during specific time intervals, and may be further improved by comparison to daily and event-based precipitation samples as well as the use of back-trajectory calculations.
Exact lower and upper bounds on stationary moments in stochastic biochemical systems
Ghusinga, Khem Raj; Vargas-Garcia, Cesar A.; Lamperski, Andrew; Singh, Abhyudai
2017-08-01
In the stochastic description of biochemical reaction systems, the time evolution of statistical moments for species population counts is described by a linear dynamical system. However, except for some ideal cases (such as zero- and first-order reaction kinetics), the moment dynamics is underdetermined as lower-order moments depend upon higher-order moments. Here, we propose a novel method to find exact lower and upper bounds on stationary moments for a given arbitrary system of biochemical reactions. The method exploits the fact that statistical moments of any positive-valued random variable must satisfy some constraints that are compactly represented through the positive semidefiniteness of moment matrices. Our analysis shows that solving moment equations at steady state in conjunction with constraints on moment matrices provides exact lower and upper bounds on the moments. These results are illustrated by three different examples—the commonly used logistic growth model, stochastic gene expression with auto-regulation and an activator-repressor gene network motif. Interestingly, in all cases the accuracy of the bounds is shown to improve as moment equations are expanded to include higher-order moments. Our results provide avenues for development of approximation methods that provide explicit bounds on moments for nonlinear stochastic systems that are otherwise analytically intractable.