scholarly journals Nonlinear Dynamics of Sea Clutter

2008 ◽  
Vol 2008 ◽  
pp. 1-7 ◽  
Author(s):  
Timothy R. Field ◽  
Simon Haykin
Keyword(s):  
Cross Section ◽  
Shape Parameter ◽  
Stochastic Dynamics ◽  
Nonlinear Behavior ◽  
Sea Clutter ◽  
Sea State ◽  
Theoretical Derivation ◽  
Radar Scattering ◽  
Points Of View

We review experimental evidence for the nonlinearity of sea clutter and the role of the z-parameter or Mann-Whitney rank-sum statistic in quantifying this nonlinear behavior in the context of a hybrid AM/FM model for sea clutter, viewed as a cyclostationary process. An independent theoretical derivation of the stochastic dynamics of radar scattering in a sea clutter environment, in terms of a pair of coupled stochastic differential equations for the received envelope and radar cross-section (RCS), enables the identification of nonlinearity in terms of the shape parameter for the RCS. We are led to conclude that, from both experimental and theoretical points of view, the dynamics of sea clutter are nonlinear with a consistent degree of nonlinearity that is determined by the sea state.

Oxygen K near edge structures studied with multiple scattering calculations

1988 ◽  
Vol 46 ◽  
pp. 504-505
Author(s):  
Xudong Weng ◽  
Peter Rez
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Partial Cross Section ◽  
Energy Window ◽  
Edge Structure ◽  
Fine Structures ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
Quantitative Chemical

In electron energy loss spectroscopy, quantitative chemical microanalysis is performed by comparison of the intensity under a specific inner shell edge with the corresponding partial cross section. There are two commonly used models for calculations of atomic partial cross sections, the hydrogenic model and the Hartree-Slater model. Partial cross sections could also be measured from standards of known compositions. These partial cross sections are complicated by variations in the edge shapes, such as the near edge structure (ELNES) and extended fine structures (ELEXFS). The role of these solid state effects in the partial cross sections, and the transferability of the partial cross sections from material to material, has yet to be fully explored. In this work, we consider the oxygen K edge in several oxides as oxygen is present in many materials. Since the energy window of interest is in the range of 20-100 eV, we limit ourselves to the near edge structures.

Synergistic Methodology Based on Ion Exchange and Biodegradation Mechanisms Applied for Metal Complex Dye Removal from Waste Waters

2018 ◽  
Vol 69 (1) ◽  
pp. 38-44
Author(s):  
Nicoleta Mirela Marin ◽  
Olga Tiron ◽  
Luoana Florentina Pascu ◽  
Mihaela Costache ◽  
Mihai Nita Lazar ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Synergistic Effects ◽  
Freundlich Isotherm ◽  
White Rot ◽  
White Rot Fungus ◽  
Basic Anion Exchange Resin ◽  
Km Value ◽  
Points Of View ◽  
Basic Anion

This study investigates the synergistic effects of ion exchange and biodegradation methods to remove the Acid Blue 193 also called Gryfalan Navy Blue RL (GNB) dye from wastewater. Ion exchange studies were performed using a strongly basic anion exchange resin Amberlite IRA 400. The equilibrium was characterized by a kinetic and thermodynamic points of view, establishing that the sorption of the GNB dye was subject to the Freundlich isotherm model with R2 = 0.8710. Experimental results showed that the activated resin can removed up to 93.4% when the concentration of dye solution is 5.62�10-2 mM. The biodegradation of the GNB was induced by laccase, an enzyme isolated from white-rot fungus. It was also analyzed the role of pH and dye concentration on GNB biodegradation, so 5�10-2 mM dye had a maximum discoloration efficiency of 82.9% at pH of 4. The laccase showed a very fast and robust activity reaching in a few minutes a Km value of 2.2�10-1mM. In addition, increasing the GNB concentration up to 8�10-1 mM did not triggered a substrat inhibition effect on the laccase activity. Overall, in this study we proposed a mixt physicochemical and biological approach to enhance the GNB removal and biodegradability from the wastewaters and subsequently the environment.

scholarly journals History, Colonialism, and Archival Methods in Socio-Hydrological Scholarship: A Case Study of the Boerasirie Conservancy in British Guiana

World ◽  
2020 ◽  
Vol 1 (3) ◽  
pp. 205-215
Author(s):  
Joshua Mullenite
Keyword(s):  
Environmental History ◽  
Cross Section ◽  
Science And Technology Studies ◽  
Model Development ◽  
Human Geography ◽  
Hydrological Models ◽  
British Guiana ◽  
Current Role

In this article, I review a cross-section of research in socio-hydrology from across disciplines in order to better understand the current role of historical-archival analysis in the development of socio-hydrological scholarship. I argue that despite its widespread use in environmental history, science and technology studies, anthropology, and human geography, archival methods are currently underutilized in socio-hydrological scholarship more broadly, particularly in the development of socio-hydrological models. Drawing on archival research conducted in relation to the socio-hydrology of coastal Guyana, I demonstrate the ways in which such scholarship can be readily incorporated into model development.

scholarly journals Actualized inventory of medicinal plants used in traditional medicine in Oaxaca, Mexico

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Cruz-Pérez Alejandra Lucía ◽  
Barrera-Ramos Jacqueline ◽  
Bernal-Ramírez Luis Alberto ◽  
Bravo-Avilez David ◽  
Rendón-Aguilar Beatriz
Keyword(s):  
Rural Communities ◽  
Medicinal Plants ◽  
Ethnic Groups ◽  
Traditional Knowledge ◽  
Original Data ◽  
Risk Category ◽  
Important Species ◽  
Points Of View ◽  
Almost All

Abstract Background Oaxaca is one of the most diverse states in Mexico from biological and cultural points of view. Different ethnic groups living there maintain deep and ancestral traditional knowledge of medicinal plants as well as traditional practices and beliefs about diseases/illnesses and cures. Previous ethnobotanical research in this state has helped document this knowledge, but with the addition of more studies, more records appear. We updated the inventory of medicinal knowledge between the different ethnic groups that inhabit the Oaxacan territory. Methods A database was constructed from two sources: (1) original data from a 3-year project in 84 municipalities of Oaxaca inhabited by eight ethnic groups and (2) different electronic databases. Results Records of 1032 medicinal plants were obtained; 164 families were registered, with Asteraceae, Fabaceae, and Rubiaceae being the most commonly used. A total of 770 species were reported in 14 vegetation types; the most important species came from temperate forests. Only 144 species corresponded to introduced species, and 272 were listed in a risk category. Illnesses of the digestive and genitourinary systems as well as culture-bound syndromes were treated with high numbers of medicinal plants. The Mestizo, Mixe, Mixtec, and Zapotec ethnic groups exhibited the greatest number of recorded medicinal plants. The 17 species that were used among almost all ethnic groups in Oaxaca were also used to cure the highest number of diseases. Discussion Inventories of medicinal plants confirm the persistence of traditional knowledge and reflect the need to recognize and respect this cosmovision. Many species are gathered in wild environments. The most important illnesses or diseases recorded in the present inventory are also mentioned in different studies, suggesting that they are common health problems in the rural communities of Mexico. Conclusions Medicinal plants are essential for ethnic groups in Oaxaca. It is necessary to recognize and understand the complex ancestral processes involved in the human-nature interaction and the role of these processes in the conservation of biodiversity and in the survivorship of ethnic groups that have persisted for centuries. Finally, this study serves as a wake-up call to respect those worldviews.

Los estereotipos sociales a través del filtro de la traducción

Babel ◽  
2014 ◽  
Vol 60 (2) ◽  
pp. 216-233
Author(s):  
Gemma Andújar Moreno
Keyword(s):  
Social Representations ◽  
Social Perceptions ◽  
Source Text ◽  
Additional Information ◽  
Social Stereotypes ◽  
Cultural Systems ◽  
The Social ◽  
Thought Patterns ◽  
Points Of View

Cultural referents not only designate specific realities of a given culture which do not always exist in another but they are also semantic elements which trigger social representations. By conveying values and points of view about different social groups, cultural referents become linguistic instruments to build stereotypes. These thought patterns are shared by the members of a social or cultural community and act as a filter of reality. The aim of this paper is to study the role of cultural referents in the construction of social stereotypes, focusing on the socio-cognitive universe they evoke. To this end, we have analyzed the translations techniques applied in the Spanish, Catalan and English versions of a novel which has been very successful on the French literary scene: Muriel Barbery’s L’Élégance du hérisson (2006). As show the results of this textual comparison, the explanations, descriptions and additional information observed in target texts do not trigger the same associations as cultural referents do in the source text. Translational approaches are too limited when it comes to achieve linguistic adequacy to different world visions. Therefore, translation must be conceived as an encounter between two cultural systems, in which the translator must build bridges, not so much between two linguistic systems as between the social perceptions and values of two different cultural communities.

scholarly journals Modeling plasma-based CO2conversion: crucial role of the dissociation cross section

2016 ◽  
Vol 25 (5) ◽  
pp. 055016 ◽  
Author(s):  
Annemie Bogaerts ◽  
Weizong Wang ◽  
Antonin Berthelot ◽  
Vasco Guerra
Keyword(s):  
Cross Section ◽  
Crucial Role ◽  
Dissociation Cross Section

On the Role of Nonlinearity in the Dynamic Behavior of Rubber Components

1986 ◽  
Vol 59 (5) ◽  
pp. 740-764 ◽  
Author(s):  
J. Harris ◽  
A. Stevenson
Keyword(s):  
Dynamic Behavior ◽  
Nonlinear Behavior ◽  
Material Composition ◽  
Geometrical Design ◽  
Linear Spring ◽  
Case Design

Abstract This paper has discussed the transmissibility behavior of rubber mounts with reference to nonlinearity originating from the material composition and from the geometrical design. It has been shown that in many cases, linear assumptions can be made, provided the limitations of these assumptions are understood. In this case, design can proceed as for a linear spring. Finally, there is some indication of how the nonlinear behavior can be exploited to advantage in the design of novel suspension components.

History, Politics, Law

2021 ◽  
Keyword(s):  
Cross Section ◽  
Political Thought ◽  
International Institutions ◽  
The Political ◽  
Global Order ◽  
The World ◽  
History Of ◽  
And Gender ◽  
The Many

Historians of political thought and international lawyers have both expanded their interest in the formation of the present global order. History, Politics, Law is the first express encounter between the two disciplines, juxtaposing their perspectives on questions of method and substance. The essays throw light on their approaches to the role of politics and the political in the history of the world beyond the single polity. They discuss the contrast between practice and theory as well as the role of conceptual and contextual analyses in both fields. Specific themes raised for both disciplines include statehood, empires and the role of international institutions, as well as the roles of economics, innovation and gender. The result is a vibrant cross-section of contrasts and parallels between the methods and practices of the two disciplines, demonstrating the many ways in which both can learn from each other.

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