971 resultados para colored lint
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Many efforts are currently oriented toward extracting more information from ocean color than the chlorophyll a concentration. Among biological parameters potentially accessible from space, estimates of phytoplankton cell size and light absorption by colored detrital matter (CDM) would lead to an indirect assessment of major components of the organic carbon pool in the ocean, which would benefit oceanic carbon budget models. We present here 2 procedures to retrieve simultaneously from ocean color measurements in a limited number of bands, magnitudes, and spectral shapes for both light absorption by CDM and phytoplankton, along with a size parameter for phytoplankton. The performance of the 2 procedures was evaluated using different data sets that correspond to increasing uncertainties: ( 1) measured absorption coefficients of phytoplankton, particulate detritus, and colored dissolved organic matter ( CDOM) and measured chlorophyll a concentrations and ( 2) SeaWiFS upwelling radiance measurements and chlorophyll a concentrations estimated from global algorithms. In situ data were acquired during 3 cruises, differing by their relative proportions in CDM and phytoplankton, over a continental shelf off Brazil. No local information was introduced in either procedure, to make them more generally applicable. Over the study area, the absorption coefficient of CDM at 443 nm was retrieved from SeaWiFS radiances with a relative root mean square error (RMSE) of 33%, and phytoplankton light absorption coefficients in SeaWiFS bands ( from 412 to 510 nm) were retrieved with RMSEs between 28% and 33%. These results are comparable to or better than those obtained by 3 published models. In addition, a size parameter of phytoplankton and the spectral slope of CDM absorption were retrieved with RMSEs of 17% and 22%, respectively. If these methods are applied at a regional scale, the performances could be substantially improved by locally tuning some empirical relationships.
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A reprint from the Annual report of the U. S. Department of agriculture, 1885.
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Irrigation is known to stimulate soil microbial carbon and nitrogen turnover and potentially the emissions of nitrous oxide (N2O) and carbon dioxide (CO2). We conducted a study to evaluate the effect of three different irrigation intensities on soil N2O and CO2 fluxes and to determine if irrigation management can be used to mitigate N2O emissions from irrigated cotton on black vertisols in South-Eastern Queensland, Australia. Fluxes were measured over the entire 2009/2010 cotton growing season with a fully automated chamber system that measured emissions on a sub-daily basis. Irrigation intensity had a significant effect on CO2 emission. More frequent irrigation stimulated soil respiration and seasonal CO2 fluxes ranged from 2.7 to 4.1 Mg-C ha−1 for the treatments with the lowest and highest irrigation frequency, respectively. N2O emission happened episodic with highest emissions when heavy rainfall or irrigation coincided with elevated soil mineral N levels and seasonal emissions ranged from 0.80 to 1.07 kg N2O-N ha−1 for the different treatments. Emission factors (EF = proportion of N fertilizer emitted as N2O) over the cotton cropping season, uncorrected for background emissions, ranged from 0.40 to 0.53 % of total N applied for the different treatments. There was no significant effect of the different irrigation treatments on soil N2O fluxes because highest emission happened in all treatments following heavy rainfall caused by a series of summer thunderstorms which overrode the effect of the irrigation treatment. However, higher irrigation intensity increased the cotton yield and therefore reduced the N2O intensity (N2O emission per lint yield) of this cropping system. Our data suggest that there is only limited scope to reduce absolute N2O emissions by different irrigation intensities in irrigated cotton systems with summer dominated rainfall. However, the significant impact of the irrigation treatments on the N2O intensity clearly shows that irrigation can easily be used to optimize the N2O intensity of such a system.
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For the evaluation, design, and planning of traffic facilities and measures, traffic simulation packages are the de facto tools for consultants, policy makers, and researchers. However, the available commercial simulation packages do not always offer the desired work flow and flexibility for academic research. In many cases, researchers resort to designing and building their own dedicated models, without an intrinsic incentive (or the practical means) to make the results available in the public domain. To make matters worse, a substantial part of these efforts pertains to rebuilding basic functionality and, in many respects, reinventing the wheel. This problem not only affects the research community but adversely affects the entire traffic simulation community and frustrates the development of traffic simulation in general. For this problem to be addressed, this paper describes an open source approach, OpenTraffic, which is being developed as a collaborative effort between the Queensland University of Technology, Australia; the National Institute of Informatics, Tokyo; and the Technical University of Delft, the Netherlands. The OpenTraffic simulation framework enables academies from geographic areas and disciplines within the traffic domain to work together and contribute to a specific topic of interest, ranging from travel choice behavior to car following, and from response to intelligent transportation systems to activity planning. The modular approach enables users of the software to focus on their area of interest, whereas other functional modules can be regarded as black boxes. Specific attention is paid to a standardization of data inputs and outputs for traffic simulations. Such standardization will allow the sharing of data with many existing commercial simulation packages.
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Filamentary single crystals, blades, sheets, euhedral crystals and powders may form by vapor phase condensation depending on the supersauration conditions in the vapor with respect to the condensing species [1]. Filamentary crystal growth requires the operation of an axial screw dislocation [2]. A Vapor-Liquid-Solid (VLS) mechanism may also produce filamentary single crystals, ribbons and blades. The latter two morphologies are typically twinned. Crystals grown by this mechanism do not require the presence of an axial screw dislocation. Impurities may either promote or inhibit crystal growth [3]. The VLS mechanism allows crystals to grow at small supersaturation of the vapor. Thin enstatite blades, ribbons and sheets have been observed in chondritic porous Interplanetary Dust Partics (IDP's) [4, 5]. The requisite screw dislocation for vapor phase condensation [1] has been observed in these enstatite blades [4]. Bradley et al. [4] suggest that these crystals are primary vapor phase condensates which could have formed either in the solar nebula or in presolar environments. These observations [4,5] are significant in that they may provide a demonstrable link to theoretical predictions: viz. that in the primordial solar nebula filamentary condensates could cluster into 'lint balls' and form the predecessors to comets [6].
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Previous studies have found that the lateral posterior fusiform gyri respond more robustly to pictures of animals than pictures of manmade objects and suggested that these regions encode the visual properties characteristic of animals. We suggest that such effects actually reflect processing demands arising when items with similar representations must be finely discriminated. In a positron emission tomography (PET) study of category verification with colored photographs of animals and vehicles, there was robust animal-specific activation in the lateral posterior fusiform gyri when stimuli were categorized at an intermediate level of specificity (e.g., dog or car). However, when the same photographs were categorized at a more specific level (e.g., Labrador or BMW), these regions responded equally strongly to animals and vehicles. We conclude that the lateral posterior fusiform does not encode domain-specific representations of animals or visual properties characteristic of animals. Instead, these regions are strongly activated whenever an item must be discriminated from many close visual or semantic competitors. Apparent category effects arise because, at an intermediate level of specificity, animals have more visual and semantic competitors than do artifacts.
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Phenols are well known noxious compounds, which are often found in various water sources. A novel analytical method has been researched and developed based on the properties of hemin–graphene hybrid nanosheets (H–GNs). These nanosheets were synthesized using a wet-chemical method, and they have peroxidase-like activity. Also, in the presence of H2O2, the nanosheets are efficient catalysts for the oxidation of the substrate, 4-aminoantipine (4-AP), and the phenols. The products of such an oxidation reaction are the colored quinone-imines (benzodiazepines). Importantly, these products enabled the differentiation of the three common phenols – pyrocatechol, resorcin and hydroquinone, with the use of a novel, spectroscopic method, which was developed for the simultaneous determination of the above three analytes. This spectroscopic method produced linear calibrations for the pyrocatechol (0.4–4.0 mg L−1), resorcin (0.2–2.0 mg L−1) and hydroquinone (0.8–8.0 mg L−1) analytes. In addition, kinetic and spectral data, obtained from the formation of the colored benzodiazepines, were used to establish multi-variate calibrations for the prediction of the three phenol analytes found in various kinds of water; partial least squares (PLS), principal component regression (PCR) and artificial neural network (ANN) models were used and the PLS model performed best.
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Recently Gao et al. proposed a lightweight RFID mutual authentication protocol [3] to resist against intermittent position trace attacks and desynchronization attacks and called it RIPTA-DA. They also verified their protocol’s security by data reduction method with the learning parity with noise (LPN) and also formally verified the functionality of the proposed scheme by Colored Petri Nets. In this paper, we investigate RIPTA-DA’s security. We present an efficient secret disclosure attack against the protocol which can be used to mount both de-synchronization and traceability attacks against the protocol. Thus our attacks show that RIPTA-DA protocol is not a RIPTA-DA.
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Business Process Management describes a holistic management approach for the systematic design, modeling, execution, validation, monitoring and improvement of organizational business processes. Traditionally, most attention within this community has been given to control-flow aspects, i.e., the ordering and sequencing of business activities, oftentimes in isolation with regards to the context in which these activities occur. In this paper, we propose an approach that allows executable process models to be integrated with Geographic Information Systems. This approach enables process models to take geospatial and other geographic aspects into account in an explicit manner both during the modeling phase and the execution phase. We contribute a structured modeling methodology, based on the well-known Business Process Model and Notation standard, which is formalized by means of a mapping to executable Colored Petri nets. We illustrate the feasibility of our approach by means of a sustainability-focused case example of a process with important ecological concerns.
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The mineral aerinite is an interesting mineral because it contains both silicate and carbonate units which is unusual. It is also a highly colored mineral being bright blue/purple. We have studied aerinite using a combination of techniques which included scanning electron microscopy, energy dispersive X-ray analysis, Raman and infrared spectroscopy. Raman bands at 1049 and 1072 cm−1 are assigned to the carbonate symmetric stretching mode. This observation supports the concept of the non-equivalence of the carbonate units in the structure of aerinite. Multiple infrared bands at 1354, 1390 and 1450 cm−1 supports this concept. Raman bands at 933 and 974 cm−1 are assigned to silicon–oxygen stretching vibrations. Multiple hydroxyl stretching and bending vibrations show that water is in different molecular environments in the aerinite structure.
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Take-it or leave-it offers are probably as old as mankind. Our objective here is, first, to provide a, probably subjectively colored, recollection of the initial ultimatum game experiment, its motivation and the immediate responses. Second, we discuss extensions of the standard ultimatum bargaining game in a unified framework, and, third, we offer a survey of the experimental ultimatum bargaining literature containing papers published since the turn of the century. The paper argues that the ultimatum game is a versatile tool for research in bargaining and on social preferences. Finally, we provide examples for open research questions and directions for future studies.
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Introduction Decreased water displacement following increased neural activity has been observed using diffusion-weighted functional MRI (DfMRI) at high b-values. The physiological mechanisms underlying the diffusion signal change may be unique from the standard blood oxygenation level-dependent (BOLD) contrast and closer to the source of neural activity. Whether DfMRI reflects neural activity more directly than BOLD outside the primary cerebral regions remains unclear. Methods Colored and achromatic Mondrian visual stimuli were statistically contrasted to functionally localize the human color center Area V4 in neurologically intact adults. Spatial and temporal properties of DfMRI and BOLD activation were examined across regions of the visual cortex. Results At the individual level, DfMRI activation patterns showed greater spatial specificity to V4 than BOLD. The BOLD activation patterns were more prominent in the primary visual cortex than DfMRI, where activation was localized to the ventral temporal lobe. Temporally, the diffusion signal change in V4 and V1 both preceded the corresponding hemodynamic response, however the early diffusion signal change was more evident in V1. Conclusions DfMRI may be of use in imaging applications implementing cognitive subtraction paradigms, and where highly precise individual functional localization is required.
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The theatrical censorship of the Third Reich considered the playwright's race and politics alongside the content of the drama. Given the political stigma of its "leftist" author, it is rather surprising that Hella Wuolijoki's Niskavuoren naiset opened in 1938 at the Staatliches Schauspielhaus in Hamburg. The play ran for fourteen performances before being closed by the Reichsdramaturgie, apparently at the instigation of Finnish critics. Yet this was not the end of the play's or its author's fortunes in the Third Reich, as the possibility of staging the play was raised several times over the next four years, coming to a close in 1942. Playing "Nordic" examines the ideological and theatrical background of this extended "cultural performance," as a means to reopening and reconstructing the work of the 1938 Die Frauen auf Niskavuori. Written by a Finnish, northern, "Nordic" author, and preoccupied with the dynamics of rural culture in an increasingly urbanized world, Niskavuoren naiset was understood in the Third Reich to illustrate and reinforce the racial, agri/cultural themes of Blut und Boden ("veri ja maa"). Playing "Nordic" examines this thematic relationship in three phases. The first phase uses archival materials to investigate the Reichsdramaturgie's understanding of the play and its author, and its ongoing discussion of Wuolijoki from 1937 to 1942. Play evaluator Sigmund Graff's description of Niskavuoren naiset as hamsunartig, or "Hamsun-esque," inspires the second phase of the dissertation, which first elaborates the meanings of Blut und Boden through a reading of contemporary "racial" theory and anthropology, and then assesses the representation of Finland within this discourse, one of the dominant cultural paradigms of the Third Reich. Imaging Finland for German audiences, the play stood among analogous, continued efforts to represent Finland and the rural life in the Third Reich, colored by Blut und Boden: art and agricultural exhibitions, essays and propaganda literature, mass demonstrations of the peasantry. This wider framework for the performance of "Finland" materializes the abstract or theoretical program of Blut und Boden in its everyday performed meanings; as such it provides the essential background for reading the Hamburg production of Die Frauen auf Niskavuori, which sustains the third and final phase. The German translation and the Hamburg photographic record are compared with the Helsinki premiere to assess the impact of Blut und Boden on the representation of Wuolijoki's play in the Third Reich. The journalistic critical response illuminates the effect that the dramatic complex of rural and racial values - generically identified as Bauerndrama in the Third Reich - had on the reception of the play; at the same time, both visual and critical documents also suggest possible moments of theatrical dissent in the Hamburg production. Playing "Nordic" undertakes a documentary and cultural reading of the changing theatrical meanings of Wuolijoki's Niskavuoren naiset as it crossed the frontier from Finland to the stage of the Third Reich. It also provides a model for the ways theatrical signification operates within a network of cultural and ideological meanings, suggesting the ideological work of theatrical production depends on, reinforces, and contests that tissue of values. Although Finnish criticism of Niskavuoren naiset has assumed the play's Blut und Boden resonance contributed to Wuolijoki's success in the Third Reich, this study shows a considerably more complex situation. This revealing production dramatizes the changing uses of plays in a politicized national and transnational context. As part of the framing of "Nordic" identity on the wider stage of the Third Reich, Die Frauen auf Niskavuori exemplifies the conjunction of concurrent - sometimes independent, sometimes interlocking - "racial" and national ideologies.
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Coloration in polyacrylonitrile can be induced in three distinct ways: by heat treatment, by treatment with base, or during synthesis of the polymer itself using ionic initiators at relatively higher temperatures. The present investigation employing 'H and NMR spectroscopy has revealed some common features in colored polyacrylonitrile irrespective of ita mode of coloration. All colored polyacrylonitriles give an additional peak around S 2.7 in 'H NMR spectra and, except for heat-treated polyacrylonitrile, one extra group of peaks in the region 8 12-16 in 13C NMR spectra. The former peak has been attributed to methine and/or methylene protons in branched and/or cyclized structures, while the latter peak has been attributed to methylene carbon atoms in the branched structure. Colorless polyacrylonitriles have been found to be predominantly heterotactic, while colored polyacrylonitriles have been found to have appreciable isotactic contribution.