466 resultados para Sat Khande
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The Kara Sea is an area uniquely suitable for studying processes in the river-sea system. This is a shallow sea, into which two great Siberian rivers, Yenisei and Ob, flow. From 1995 to 2003, the sea was studied by six international expeditions onboard the R/V Akademik Boris Petrov. This publication summarizes the results obtained, within the framework of this project, at the Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences. Various hydrogeochemical parameters, concentrations and isotopic composition of organic and carbonate carbon of the sediments, plankton, particulate organic matter, hydrocarbons, and dissolved CO2 were examined throughout the whole sea area at more than 200 sites. The d13C varies from -22 and -24 per mil where Atlantic waters enter the Kara Sea and in the north-eastern part of the water area to -27 per mil in the Yenisei and Ob estuaries. The value of d13C of the plankton is only weakly correlated with the d13C of the organic matter from the sediments and is lower by as much as 3-4 per mil. The paper presents the results obtained from a number of meridional river-sea profiles. It was determined from the relations between the isotopic compositions of plankton and particulate matter that the river waters carry material consisting of 70% detrital-humus matter and 30% planktonogenic material in the river part, and the material contained in the offshore waters consists of 30% terrigenous components, with the contribution of bioproducers amounting to 70%. The carbon isotopic composition of the plankton ranges from -29 to -35 per mil in the riverine part, from -28 to -27 per mil in the estuaries, and from -27.0 to -25 per mil in the marine part. The relative lightness of the carbon isotopic composition of plankton in Arctic waters is explained by the temperature effect, elevated CO2 concentrations, and long-distance CO2 supply to the sea with river waters. The data obtained on the isotopic composition of CO2 in the surface waters of the Kara Sea were used to map the distribution of d13C. The complex of hydrocarbon gases extracted from the waters included methane, C2-C5, and unsaturated C2=-C4= hydrocarbons, for which variations in the concentrations in the waters were studied along river-estuary-sea profiles. The geochemistry of hydrocarbon gases in surface fresh waters is characterized by comparable concentrations of methane (0.3-5 µl/l) and heavier hydrocarbons, including unsaturated ones. Microbiological methane with d13C from -105 to -90 per mil first occurs in the sediments at depths of 40-200 cm. The sediments practically everywhere display traces of methane oxidation in the form of a shift of the d13C of methane toward higher values and the occurrence of autogenic carbonate material, including ikaite, enriched in the light isotope. Ikaite (d13C from -25 to -60 per mil) was found and examined in several profiles. The redox conditions in the sediments varied from normal in the southern part of the sea to highly oxidized along the Novaya Zemlya Trough. Vertical sections through the sediments of the latter exemplify the complete suppression of the biochemical activity of microorganisms. Our data provide insight into the biogeochemistry of the Kara Sea and make it possible to specify the background values needed for ecological control during the future exploration operations and extraction of hydrocarbons in the Kara Sea.
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Global change is affecting marine ecosystems through a combination of different stressors such as warming, ocean acidification and oxygen depletion. Very little is known about the interactions among these factors, especially with respect to gelatinous zooplankton. Therefore, in this study we investigated the direct effects of pH, temperature and oxygen availability on the moon jellyfish Aurelia aurita, concentrating on the ephyral life stage. Starved one-day-old ephyrae were exposed to a range of pCO2 (400-4000 ppm) and three different dissolved oxygen levels (from saturated to hypoxic conditions), in two different temperatures (5 and 15 °C) for 7 days. Carbon content and swimming activity were analysed at the end of the incubation period, and mortality noted. General linearized models were fitted through the data, with the best fitting models including two- and three-way interactions between pCO2, temperature and oxygen concentration. The combined effect of the stressors was small but significant, with the clearest negative effect on growth caused by the combination of all three stressors present (high temperature, high CO2, low oxygen). We conclude that A. aurita ephyrae are robust and that they are not likely to suffer from these environmental stressors in a near future.
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For the past several years, U.S. colleges and universities have faced increased pressure to improve retention and graduation rates. At the same time, educational institutions have placed a greater emphasis on the importance of enrolling more students in STEM (science, technology, engineering and mathematics) programs and producing more STEM graduates. The resulting problem faced by educators involves finding new ways to support the success of STEM majors, regardless of their pre-college academic preparation. The purpose of my research study involved utilizing first-year STEM majors’ math SAT scores, unweighted high school GPA, math placement test scores, and the highest level of math taken in high school to develop models for predicting those who were likely to pass their first math and science courses. In doing so, the study aimed to provide a strategy to address the challenge of improving the passing rates of those first-year students attempting STEM-related courses. The study sample included 1018 first-year STEM majors who had entered the same large, public, urban, Hispanic-serving, research university in the Southeastern U.S. between 2010 and 2012. The research design involved the use of hierarchical logistic regression to determine the significance of utilizing the four independent variables to develop models for predicting success in math and science. The resulting data indicated that the overall model of predictors (which included all four predictor variables) was statistically significant for predicting those students who passed their first math course and for predicting those students who passed their first science course. Individually, all four predictor variables were found to be statistically significant for predicting those who had passed math, with the unweighted high school GPA and the highest math taken in high school accounting for the largest amount of unique variance. Those two variables also improved the regression model’s percentage of correctly predicting that dependent variable. The only variable that was found to be statistically significant for predicting those who had passed science was the students’ unweighted high school GPA. Overall, the results of my study have been offered as my contribution to the literature on predicting first-year student success, especially within the STEM disciplines.
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The data files give the basic field and laboratory data on five ponds in the northeast Siberian Arctic tundra on Samoylov. The files contain water and soil temperature data of the ponds, methane fluxes, measured with closed chambers in the centres without vascular plants and the margins with vascular plants, the contribution of plant mediated fluxes on total methane fluxes, the gas concentrations (methane and dissolved inorganic carbon, oxygen) in the soil and the water column of the ponds, microbial activities (methane production, methane oxidation, aerobic and anaerobic carbon dioxide production), total carbon pools in the different horizons of the bottom soils, soil bulk density, soil substance density, and soil porosity.
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The Southern Ocean ecosystem at the Antarctic Peninsula has steep natural environmental gradients, e.g. in terms of water masses and ice cover, and experiences regional above global average climate change. An ecological macroepibenthic survey was conducted in three ecoregions in the north-western Weddell Sea, on the continental shelf of the Antarctic Peninsula in the Bransfield Strait and on the shelf of the South Shetland Islands in the Drake Passage, defined by their environmental envelop. The aim was to improve the so far poor knowledge of the structure of this component of the Southern Ocean ecosystem and its ecological driving forces. It can also provide a baseline to assess the impact of ongoing climate change to the benthic diversity, functioning and ecosystem services. Different intermediate-scaled topographic features such as canyon systems including the corresponding topographically defined habitats 'bank', 'upper slope', 'slope' and 'canyon/deep' were sampled. In addition, the physical and biological environmental factors such as sea-ice cover, chlorophyll-a concentration, small-scale bottom topography and water masses were analysed. Catches by Agassiz trawl showed high among-station variability in biomass of 96 higher systematic groups including ecological key taxa. Large-scale patterns separating the three ecoregions from each other could be correlated with the two environmental factors, sea-ice and depth. Attribution to habitats only poorly explained benthic composition, and small-scale bottom topography did not explain such patterns at all. The large-scale factors, sea-ice and depth, might have caused large-scale differences in pelagic benthic coupling, whilst small-scale variability, also affecting larger scales, seemed to be predominantly driven by unknown physical drivers or biological interactions.
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This data report includes the analytical results of about 220 water wamples collected at 33 stations in the Fjords of Kiel ,...
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The presented thesis was written in the frame of a project called 'seepage water prognosis'. It was funded by the Federal Ministry for Education and Science (BMBF). 41 German institutions among them research institutes of universities, public authorities and engineering companies were financed for three years respectively. The aim was to work out the scientific basis that is needed to carry out a seepage water prognosis (Oberacker und Eberle, 2002). According to the Federal German Soil Protection Act (Federal Bulletin, 1998) a seepage water prognosis is required in order to avoid future soil impacts from the application of recycling products. The participants focused on the development of either methods to determine the source strength of the materials investigated, which is defined as the total mass flow caused by natural leaching or on models to predict the contaminants transport through the underlying soil. Annual meetings of all participants as well as separate meetings of the two subprojects were held. The department of Geosciences in Bremen participated with two subprojects. The aim of the subproject that resulted in this thesis was the development of easily applicable, valid, and generally accepted laboratory methods for the determination of the source strength. In the scope of the second subproject my colleague Veith Becker developed a computer model for the transport prognosis with the source strength as the main input parameter.
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The substantive legislation on which Agricultural Processing Companies is based has some notable gaps with regard to the pertinent accounting system. There are grey areas concerning compulsory accounting records and their legalization, together with the process for drawing up, checking, approving and depositing the annual accounts.Consequently, in this paper, we will look first at the corporate and accounting records for Agricultural Processing Companies, putting forward proposals in the wake of recent legislation on the legalization of generally applied corporate and accounting documents.A critical analysis will also be made of the entire process of drafting, auditing, approving and depositing the annual accounts and other documents that Agricultural Processing Companies must send each year to their respective regional registries. Legal and mercantile registries will be differentiated from administrative ones and, in this last sense, changes will be suggested with regard to the place and objective of the deposit of such documents.After thirty-four years old, the substantive legislation in economic and accounting matters of the SAT is out of step with the current law, so a review is necessary. Recent regional regulations have not been a real breakthrough in this regard. We assert the existence of a gap between the substantive rules of the SAT and general accounting rules on financial statements, which is unsustainable and it needs a quick legislative action to be canceled.
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Introdução: A qualidade da vinculação da criança aos pais é fundamental para o seu desenvolvimento sócio-emocional, na medida em que lhe permite explorar o meio envolvente, relacionar-se com outras pessoas e fazer novas aprendizagens. No que respeita ao estudo da vinculação em diferentes tipos de família, a literatura tem indicado que as crianças de famílias nucleares apresentam uma vinculação mais segura em relação às crianças de famílias monoparentais ou reconstituídas. Objectivo: Este estudo tem por objectivos investigar a qualidade da vinculação em crianças em idade escolar pertencentes a diferentes tipos de família e observar a convergência entre a percepção materna dos comportamentos de vinculação e a representação da qualidade de vinculação por parte das crianças em estudo. Metodologia: Trata-se de um estudo transversal, cuja amostra é composta por 168 crianças em idade escolar (8-11 anos) e respectivas mães. O protocolo de investigação é constituído por 3 instrumentos: Questionário sócio-demográfico, Separation Anxiety Test (SAT) e Escala de Percepção Materna do Comportamento de Vinculação da Criança (PCV-M). Resultados: Os resultados mostram não haver convergência significativa entre a percepção materna dos comportamentos de vinculação e a representação da vinculação por parte da criança. Somente nas famílias monoparentais são observáveis correlações entre a subescala Comportamento Base Segura do PCV-M (p=.001, p<.01) e a representação da vinculação da criança medida pelo SAT (seguras: M=31.614; inseguras: M=27.167). Observam-se diferenças na percepção materna do comportamento de vinculação da criança nos diferentes tipos de família (p=.022, α<.05) e são as mães de famílias reconstituídas que reconhecem mais dificuldades de auto-regulação emocional nos seus filhos (M=46.16). Por fim, o tipo de família não é preditor da qualidade da vinculação da criança (χ2(2) = .485, p < .785). Conclusão: Os resultados sugerem que a qualidade da vinculação das crianças não varia em função do tipo de família a que pertencem e revelam uma baixa convergência entre as perspectivas de mães e filhos no que respeita à qualidade da vinculação destes.
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This paper consists in a study case at the Alesat company, which aims at analyzing how the networks from the former companies Ale and Sat influence the formation of partnerships. The study was based on literature by Burt (1992), Granovetter (1973), Uzzi (1997), Contractor and Lorange (1988), Gulati (1998), Child and Faulkner (1998), and others, to verify how important the social relations were between the companies to the formation of a strategic alliance. The research method we adopted analyzed the first partnership between Ale and Sat and the last one that ended up with the merger of the companies resulting in a new company, Alesat. Semi-structured interviews were conducted in 2008 with the council board of the company. Secondary data were also collected from specific web sites from the area, such as ANP, Sindicom and Fecombustíveis, as well as from important newspapers in the market. The primary data were analyzed through the content analysis technique from Triviños (1987). The secondary data were analyzed through the documental analysis technique from Richardson (1985). This way, through the data collected, it can be concluded that the social ties between the companies were important in the partnership, and among the reasons that made the companies get together, the key one was the fact that the union would make possible to the companies act in regions in which they didn t have too much market share, making them a bigger player nationally wise
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Contemporary integrated circuits are designed and manufactured in a globalized environment leading to concerns of piracy, overproduction and counterfeiting. One class of techniques to combat these threats is circuit obfuscation which seeks to modify the gate-level (or structural) description of a circuit without affecting its functionality in order to increase the complexity and cost of reverse engineering. Most of the existing circuit obfuscation methods are based on the insertion of additional logic (called “key gates”) or camouflaging existing gates in order to make it difficult for a malicious user to get the complete layout information without extensive computations to determine key-gate values. However, when the netlist or the circuit layout, although camouflaged, is available to the attacker, he/she can use advanced logic analysis and circuit simulation tools and Boolean SAT solvers to reveal the unknown gate-level information without exhaustively trying all the input vectors, thus bringing down the complexity of reverse engineering. To counter this problem, some ‘provably secure’ logic encryption algorithms that emphasize methodical selection of camouflaged gates have been proposed previously in literature [1,2,3]. The contribution of this paper is the creation and simulation of a new layout obfuscation method that uses don't care conditions. We also present proof-of-concept of a new functional or logic obfuscation technique that not only conceals, but modifies the circuit functionality in addition to the gate-level description, and can be implemented automatically during the design process. Our layout obfuscation technique utilizes don’t care conditions (namely, Observability and Satisfiability Don’t Cares) inherent in the circuit to camouflage selected gates and modify sub-circuit functionality while meeting the overall circuit specification. Here, camouflaging or obfuscating a gate means replacing the candidate gate by a 4X1 Multiplexer which can be configured to perform all possible 2-input/ 1-output functions as proposed by Bao et al. [4]. It is important to emphasize that our approach not only obfuscates but alters sub-circuit level functionality in an attempt to make IP piracy difficult. The choice of gates to obfuscate determines the effort required to reverse engineer or brute force the design. As such, we propose a method of camouflaged gate selection based on the intersection of output logic cones. By choosing these candidate gates methodically, the complexity of reverse engineering can be made exponential, thus making it computationally very expensive to determine the true circuit functionality. We propose several heuristic algorithms to maximize the RE complexity based on don’t care based obfuscation and methodical gate selection. Thus, the goal of protecting the design IP from malicious end-users is achieved. It also makes it significantly harder for rogue elements in the supply chain to use, copy or replicate the same design with a different logic. We analyze the reverse engineering complexity by applying our obfuscation algorithm on ISCAS-85 benchmarks. Our experimental results indicate that significant reverse engineering complexity can be achieved at minimal design overhead (average area overhead for the proposed layout obfuscation methods is 5.51% and average delay overhead is about 7.732%). We discuss the strengths and limitations of our approach and suggest directions that may lead to improved logic encryption algorithms in the future. References: [1] R. Chakraborty and S. Bhunia, “HARPOON: An Obfuscation-Based SoC Design Methodology for Hardware Protection,” IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, vol. 28, no. 10, pp. 1493–1502, 2009. [2] J. A. Roy, F. Koushanfar, and I. L. Markov, “EPIC: Ending Piracy of Integrated Circuits,” in 2008 Design, Automation and Test in Europe, 2008, pp. 1069–1074. [3] J. Rajendran, M. Sam, O. Sinanoglu, and R. Karri, “Security Analysis of Integrated Circuit Camouflaging,” ACM Conference on Computer Communications and Security, 2013. [4] Bao Liu, Wang, B., "Embedded reconfigurable logic for ASIC design obfuscation against supply chain attacks,"Design, Automation and Test in Europe Conference and Exhibition (DATE), 2014 , vol., no., pp.1,6, 24-28 March 2014.
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El problema de selección de requisitos (o Next Release Problem, NRP) consiste en seleccionar el subconjunto de requisitos que se va a desarrollar en la siguiente versión de una aplicación software. Esta selección se debe hacer de tal forma que maximice la satisfacción de las partes interesadas a la vez que se minimiza el esfuerzo empleado en el desarrollo y se cumplen un conjunto de restricciones. Trabajos recientes han abordado la formulación bi-objetivo de este problema usando técnicas exactas basadas en resolutores SAT y resolutores de programación lineal entera. Ambos se enfrentan a dificultades cuando las instancias tienen un gran tamaño, sin embargo la programación lineal entera (ILP) parece ser más efectiva que los resolutores SAT. En la práctica, no es necesario calcular todas las soluciones del frente de Pareto (que pueden llegar a ser muchas) y basta con obtener un buen número de soluciones eficientes bien distribuidas en el espacio objetivo. Las estrategias de búsqueda basadas en ILP que se han utilizado en el pasado para encontrar un frente bien distribuido en cualquier instante de tiempo solo buscan soluciones soportadas. En este trabajo proponemos dos estrategias basadas en ILP que son capaces de encontrar el frente completo con suficiente tiempo y que, además, tienen la propiedad de aportar un conjunto de soluciones bien distribuido en el frente objetivo en cualquier momento de la búsqueda.
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Symbolic execution is a powerful program analysis technique, but it is very challenging to apply to programs built using event-driven frameworks, such as Android. The main reason is that the framework code itself is too complex to symbolically execute. The standard solution is to manually create a framework model that is simpler and more amenable to symbolic execution. However, developing and maintaining such a model by hand is difficult and error-prone. We claim that we can leverage program synthesis to introduce a high-degree of automation to the process of framework modeling. To support this thesis, we present three pieces of work. First, we introduced SymDroid, a symbolic executor for Android. While Android apps are written in Java, they are compiled to Dalvik bytecode format. Instead of analyzing an app’s Java source, which may not be available, or decompiling from Dalvik back to Java, which requires significant engineering effort and introduces yet another source of potential bugs in an analysis, SymDroid works directly on Dalvik bytecode. Second, we introduced Pasket, a new system that takes a first step toward automatically generating Java framework models to support symbolic execution. Pasket takes as input the framework API and tutorial programs that exercise the framework. From these artifacts and Pasket's internal knowledge of design patterns, Pasket synthesizes an executable framework model by instantiating design patterns, such that the behavior of a synthesized model on the tutorial programs matches that of the original framework. Lastly, in order to scale program synthesis to framework models, we devised adaptive concretization, a novel program synthesis algorithm that combines the best of the two major synthesis strategies: symbolic search, i.e., using SAT or SMT solvers, and explicit search, e.g., stochastic enumeration of possible solutions. Adaptive concretization parallelizes multiple sub-synthesis problems by partially concretizing highly influential unknowns in the original synthesis problem. Thanks to adaptive concretization, Pasket can generate a large-scale model, e.g., thousands lines of code. In addition, we have used an Android model synthesized by Pasket and found that the model is sufficient to allow SymDroid to execute a range of apps.
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Con el objetivo de determinar el aporte en nutrientes digestibles para cerdos de dos tipos de sorgo procesados por distintos métodos, se realizó una prueba de digestibilidad fecal aparente (DFA) con cerdos en recría. Se estudiaron seis dietas: T1: maíz molido (MM); T2: sorgo alto tanino (SAT) molido (SATM); T3: SAT extrusado (SATE); T4: silo de grano húmedo de SAT (SSAT); T5: sorgo de bajo tanino (SBT) molido (SBTM); T6: silo de grano húmedo de SBT (SSBT). Se utilizaron 18 cerdos, tres por tratamiento, con un peso promedio de 36,5 kg, alojados en jaulas de digestibilidad individuales. El periodo experimental comprendió siete días de acostumbramiento y cinco de recolección de heces. Se suministraron dos tomas diarias iguales, de una cantidad de materia seca equivalente el 6 % del peso metabólico corporal. Se realizó recolección total de heces. Se determinó la DFA de materia seca (MS), materia orgánica (MO), proteína cruda (PC) y energía bruta (EB). Se estimó el aporte en base seca de Proteína Digestible y Energía Digestible. Los resultados de DFA de MS, MO, PC y EB, en porcentaje, fueron respectivamente, MM: 90,27; 90,18; 81,65; 89,74; SATM: 89,45; 89,29; 73,31; 88,96; SATE: 90,78; 90,64; 81,94; 91,24; SSAT: 83,58; 83,41; 49,11; 83,22; SBTM: 91,23; 91,09; 72,63; 90,83; SSBT: 93,16; 93,05; 83,55; 92,78. Se concluye que el SBTM, el SSBT y el SATE tienen un valor nutritivo equivalente al maíz.