886 resultados para Relationship with educational system


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With ever increasing network speed, scalable and reliable detection of network port scans has become a major challenge. In this paper, we present a scalable and flexible architecture and a novel algorithm, to detect and block port scans in real time. The proposed architecture detects fast scanners as well as stealth scanners having large inter-probe periods. FPGA implementation of the proposed system gives an average throughput of 2 Gbps with a system clock frequency of 100 MHz on Xilinx Virtex-II Pro FPGA. Experimental results on real network trace show the effectiveness of the proposed system in detecting and blocking network scans with very low false positives and false negatives.

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This work is a continuation of our efforts to quantify the irregular scalar stress signals from the Ananthakrishna model for the Portevin-Le Chatelier instability observed under constant strain rate deformation conditions. Stress related to the spatial average of the dislocation activity is a dynamical variable that also determines the time evolution of dislocation densities. We carry out detailed investigations on the nature of spatiotemporal patterns of the model realized in the form of different types of dislocation bands seen in the entire instability domain and establish their connection to the nature of stress serrations. We then characterize the spatiotemporal dynamics of the model equations by computing the Lyapunov dimension as a function of the drive parameter. The latter scales with the system size only for low strain rates, where isolated dislocation bands are seen, and at high strain rates, where fully propagating bands are seen. At intermediate applied strain rates corresponding to the partially propagating bands, the Lyapunov dimension exhibits two distinct slopes, one for small system sizes and another for large. This feature is rationalized by demonstrating that the spatiotemporal patterns for small system sizes are altered from the partially propagating band types to isolated burst type. This in turn allows us to reconfirm that low-dimensional chaos is projected from the stress signals as long as there is a one-to-one correspondence between the bursts of dislocation bands and the stress drops. We then show that the stress signals in the regime of partially to fully propagative bands have features of extensive chaos by calculating the correlation dimension density. We also show that the correlation dimension density also depends on the system size. A number of issues related to the system size dependence of the Lyapunov dimension density and the correlation dimension density are discussed.

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Overland rain retrieval using spaceborne microwave radiometer offers a myriad of complications as land presents itself as a radiometrically warm and highly variable background. Hence, land rainfall algorithms of the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) have traditionally incorporated empirical relations of microwave brightness temperature (Tb) with rain rate, rather than relying on physically based radiative transfer modeling of rainfall (as implemented in the TMI ocean algorithm). In this paper, sensitivity analysis is conducted using the Spearman rank correlation coefficient as benchmark, to estimate the best combination of TMI low-frequency channels that are highly sensitive to the near surface rainfall rate from the TRMM Precipitation Radar (PR). Results indicate that the TMI channel combinations not only contain information about rainfall wherein liquid water drops are the dominant hydrometeors but also aid in surface noise reduction over a predominantly vegetative land surface background. Furthermore, the variations of rainfall signature in these channel combinations are not understood properly due to their inherent uncertainties and highly nonlinear relationship with rainfall. Copula theory is a powerful tool to characterize the dependence between complex hydrological variables as well as aid in uncertainty modeling by ensemble generation. Hence, this paper proposes a regional model using Archimedean copulas, to study the dependence of TMI channel combinations with respect to precipitation, over the land regions of Mahanadi basin, India, using version 7 orbital data from the passive and active sensors on board TRMM, namely, TMI and PR. Studies conducted for different rainfall regimes over the study area show the suitability of Clayton and Gumbel copulas for modeling convective and stratiform rainfall types for the majority of the intraseasonal months. Furthermore, large ensembles of TMI Tb (from the most sensitive TMI channel combination) were generated conditional on various quantiles (25th, 50th, 75th, and 95th) of the convective and the stratiform rainfall. Comparatively greater ambiguity was observed to model extreme values of the convective rain type. Finally, the efficiency of the proposed model was tested by comparing the results with traditionally employed linear and quadratic models. Results reveal the superior performance of the proposed copula-based technique.

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The sensitivity of combustion phasing and combustion descriptors to ignition timing, load and mixture quality on fuelling a multi-cylinder natural gas engine with bio-derived H-2 and CO rich syngas is addressed. While the descriptors for conventional fuels are well established and are in use for closed loop engine control, presence of H-2 in syngas potentially alters the mixture properties and hence combustion phasing, necessitating the current study. The ability of the descriptors to predict abnormal combustion, hitherto missing in the literature, is also addressed. Results from experiments using multi-cylinder engines and numerical studies using zero dimensional Wiebe function based simulation models are reported. For syngas with 20% H-2 and CO and 2% CH4 (producer gas), an ignition retard of 5 +/- 1 degrees was required compared to natural gas ignition timing to achieve peak load of 72.8 kWe. It is found that, for syngas, whose flammability limits are 0.42-1.93, the optimal engine operation was at an equivalence ratio of 1.12. The same methodology is extended to a two cylinder engine towards addressing the influence of syngas composition, especially H-2 fraction (varying from 13% to 37%), on the combustion phasing. The study confirms the utility of pressure trace derived combustion descriptors, except for the pressure trace first derivative, in describing the MBT operating condition of the engine when fuelled with an alternative fuel. Both experiments and analysis suggest most of the combustion descriptors to be independent of the engine load and mixture quality. A near linear relationship with ignition angle is observed. The general trend(s) of the combustion descriptors for syngas fuelled operation are similar to those of conventional fuels; the differences in sensitivity of the descriptors for syngas fuelled engine operation requires re-calibration of control logic for MBT conditions. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

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In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3-5 degrees C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig-pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within-tree reproductive phenology via the feedback cycle in this system. Climatic factors affecting plant reproductive traits cause biotic relationships between plants, mutualists and parasites to vary seasonally and must be accorded greater attention, especially in the context of climate change.

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We present a localization system that targets rapid deployment of stationary wireless sensor networks (WSN). The system uses a particle filter to fuse measurements from multiple localization modalities, such as RF ranging, neighbor information or maps, to obtain position estimations with higher accuracy than that of the individual modalities. The system isolates different modalities into separate components which can be included or excluded independently to tailor the system to a specific scenario. We show that position estimations can be improved with our system by combining multiple modalities. We evaluate the performance of the system in both an indoor and outdoor environment using combinations of five different modalities. Using two anchor nodes as reference points and combining all five modalities, we obtain RMS (Root Mean Square) estimation errors of approximately 2.5m in both cases, while using the components individually results in errors within the range of 3.5 and 9 m.

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We carried out a large-scale phylogenetic analysis of fejervaryan (dicroglossid frogs with `Fejervaryan lines' on the ventral side of the body) frogs, distributed in South and SE Asia, using published and newly generated sequences of unidentified individuals from the northern Western Ghats. The results corroborate the presence of a larger fejervaryan clade with a sister relationship to a clade composed of Sphaerotheca. Two sister clades could be discerned within the lager fejervaryan clade. The unidentified individuals formed a monophyletic group and showed a strong support for a sister relationship with Minervarya sahyadris. The species was found to be highly divergent (16S rRNA-4% and tyr-1%) from its sister lineage Minervarya sahyadris, and the clade composed of these two lineages were found to be deeply nested within the larger clade of Fejervarya. Based on this, the genus Minervarya Dubois, Ohler and Biju, 2001 is synonymized under the genus Fejervarya Bolkay, 1915. The unidentified lineage is recognized, based on phylogenetic position, genetic divergence and morphological divergence, as a distinct species and named here as Fejervarya gomantaki sp. nov. The presence of rictal glands was observed to be a synapomorphic character shared by the nested clade members, Fejervarya sahyadris and Fejervarya gomantaki sp. nov. Based on the presence of rictal gland and small size, Minervarya chilapata, a species from a lowland region in the Eastern Himalayas, is synonymized under Fejervarya and evidence for morphological separation from the new species, Fejervarya gomantaki sp. nov. is provided. For the fejervaryan frogs, currently three generic names (Frost, 2015) are available for the two phylogenetic subclades; the genus Fejervarya Bolkay, 1915 for the species of fejervaryan frogs having distribution in the South East Asia; the genus Zakerana Howlader, 2011 for the species of fejervaryan frogs having distribution in the South Asia and the genus Minervarya Dubois, Ohler and Biju, 2001 nested within the `Zakerana clade'. In the phylogenetic analysis Minervarya sahyadris, the new species described herein as Fejervarya gomantaki sp. nov. are nested within the `Zakerana clade', if the `Zakerana clade' for the fejervaryan frogs having distribution in the South Asia is provided a generic status the nomen `Minervarya' should be considered as per the principle of priority of the ICZN Code. Taking into consideration the overlapping distribution ranges of members of the sister clades within the larger fejervaryan clade and the absence of distinct morphological characteristics, we also synonymize the genus Zakerana Howlader, 2011, a name assigned to one of the sister clades with members predominantly distributed in South Asia, under the genus Fejervarya Bolkay, 1915. We discuss the need for additional sampling to identify additional taxa and determine the geographical ranges of the members of the sister clades within Fejervarya to resolve taxonomy within this group.

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Approximately 140 million years ago, the Indian plate separated from Gondwana and migrated by almost 90 degrees latitude to its current location, forming the Himalayan-Tibetan system. Large discrepancies exist in the rate of migration of Indian plate during Phanerozoic. Here we describe a new approach to paleo-latitudinal reconstruction based on simultaneous determination of carbonate formation temperature and delta O-18 of soil carbonates, constrained by the abundances of C-13-O-18 bonds in palaeosol carbonates. Assuming that the palaeosol carbonates have a strong relationship with the composition of the meteoric water, delta O-18 carbonate of palaeosol can constrain paleo-latitudinal position. Weighted mean annual rainfall delta O-18 water values measured at several stations across the southern latitudes are used to derive a polynomial equation: delta(18)Ow = -0.006 x (LAT)(2) - 0.294 x (LAT) - 5.29 which is used for latitudinal reconstruction. We use this approach to show the northward migration of the Indian plate from 46.8 +/- 5.8 degrees S during the Permian (269 M. y.) to 30 +/- 11 degrees S during the Triassic (248 M. y.), 14.7 +/- 8.7 degrees S during the early Cretaceous (135 M. y.), and 28 +/- 8.8 degrees S during the late Cretaceous ( 68 M. y.). Soil carbonate delta O-18 provides an alternative method for tracing the latitudinal position of Indian plate in the past and the estimates are consistent with the paleo-magnetic records which document the position of Indian plate prior to 135 +/- 3 M. y.

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In the present paper, it is shown that the zero series eigenfunctions of Reissner plate cracks/notches fracture problems are analogous to the eigenfunctions of anti-plane and in-plane. The singularity in the double series expression of plate problems only arises in zero series parts. In view of the relationship with eigen-values of anti-plane and in-plane problem, the solution of eigen-values for Reissner plates consists of two parts: anti-plane problem and in-plane problem. As a result the corresponding eigen-values or the corresponding eigen-value solving programs with respect to the anti-plane and in-plane problems can be employed and many aggressive SIF computed methods of plane problems can be employed in the plate. Based on those, the approximate relationship of SIFs between the plate and the plane fracture problems is figured out, and the effect relationship of the plate thickness on SIF is given.

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Resumen: Este artículo se inscribe en investigaciones realizadas para Conicet sobre la incidencia del surgimiento de las facultades rosarinas de la Universidad Nacional del Litoral en la conformación de un sistema regional de innovación científica, y su relación con la dinámica local y la expansión de las redes profesionales. Centra su enfoque en uno de los articuladores del mencionado proceso, el doctor Artemio Zeno, quién fuera fundador de una nueva escuela en la práctica quirúrgica, catedrático titular de la Facultad de Ciencias Médicas de Rosario, empresario de la salud, promotor de publicaciones científicas y de vinculaciones con los principales institutos de investigación internacional, al punto de publicar y dirigir la Revista de Cirugía, del Sanatorio Británico, y crear la primera Fundación médica de Latinoamérica dedicada exclusivamente a becar investigadores de los países del cono sur que quisieran especializarse en la especialidad quirúrgica.

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The article analyzes the legal regime of Euskara in the education system of the Autonomous Community of the Basque Country (capv). In the capv, the legislation recognizes the right to choose the language of study during the educational cycle. The students are separated into different classrooms based on their language preference. This system of separation (of language models) has made it possible to make great strides, although its implementation also suggests aspects which, from the perspective of a pluralistic Basque society on its way towards greater social, political and language integration, call for further reflection The general model for language planning in the capv was fashioned in the eighties as a model characterized by the guarantee of spaces of language freedom, and the educational system was charged with making the learning of the region’s autochthonous language more widespread. At this point, we already have a fair degree of evidence on which to base an analysis of the system of language models and we are in a position to conclude that perhaps the educational system was given too heavy a burden. Official studies on language performance of Basque schoolchildren show (in a way that is now fully verified) that not all the students who finish their mandatory period of schooling achieve the level of knowledge of Euskara required by the regulations. When faced with this reality, it becomes necessary for us to articulate some alternative to the current configuration of the system of language models, one that will make it possible in the future to have a Basque society that is linguistically more integrated, thereby avoiding having the knowledge or lack of knowledge of one of the official languages become a language barrier between two communities. Many sides have urged a reconsideration of the system of language models. The Basque Parliament itself has requested the Department of Education to design a new system. This article analyzes the legal foundations on which the current system is built and explores the potential avenues for legal cooperation that would make it possible to move towards a new system aimed at guaranteeing higher rates of bilingualism. The system would be sufficiently flexible so as to be able to respond to and accommodate the different sociolinguistic realities of the region.

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For a long time, the Tanzanian Fisheries Department has managed Tanzanian fisheries without incorporating other stakeholders within its management framework. On lake Victoria, the persistent use of illegal fishing gear and declining catches have led the government to realize that this system of fisheries management may no longer be viable, and have sought to incorporate fishing communities into the management structure. Through the creation of beach management units (BMUs), the Fisheries Departments have sought to persuade fishing communities to implement and enforce Tanzania's fishing regulations and to monitor the fishery. In this paper we explore a recently gathered data set that yields information on, amongst others, how Tanzanian fishing communities perceive the state of their resource base, how they view their relationship with the Fisheries Department, the efficacy of fishing regulations and other variables. We draw on a series of criteria developed by Ostron (1990) for institutional 'robustness' to explore various areas of institutional development on Lake Victoria, and to try and anticipate how the BMUs will fare. We argue there are many socio-political and economic factors that will determine how communities will receive and perceive their responsibilities towards government-imposed administrative structures at the local level, these will become 'socialized' such that they will vary from place to place. While this may bode well for problems of heterogeneity, it does not necessarily mean that fisheries management objective on Lake Victoria will be met

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Quantum computing offers powerful new techniques for speeding up the calculation of many classically intractable problems. Quantum algorithms can allow for the efficient simulation of physical systems, with applications to basic research, chemical modeling, and drug discovery; other algorithms have important implications for cryptography and internet security.

At the same time, building a quantum computer is a daunting task, requiring the coherent manipulation of systems with many quantum degrees of freedom while preventing environmental noise from interacting too strongly with the system. Fortunately, we know that, under reasonable assumptions, we can use the techniques of quantum error correction and fault tolerance to achieve an arbitrary reduction in the noise level.

In this thesis, we look at how additional information about the structure of noise, or "noise bias," can improve or alter the performance of techniques in quantum error correction and fault tolerance. In Chapter 2, we explore the possibility of designing certain quantum gates to be extremely robust with respect to errors in their operation. This naturally leads to structured noise where certain gates can be implemented in a protected manner, allowing the user to focus their protection on the noisier unprotected operations.

In Chapter 3, we examine how to tailor error-correcting codes and fault-tolerant quantum circuits in the presence of dephasing biased noise, where dephasing errors are far more common than bit-flip errors. By using an appropriately asymmetric code, we demonstrate the ability to improve the amount of error reduction and decrease the physical resources required for error correction.

In Chapter 4, we analyze a variety of protocols for distilling magic states, which enable universal quantum computation, in the presence of faulty Clifford operations. Here again there is a hierarchy of noise levels, with a fixed error rate for faulty gates, and a second rate for errors in the distilled states which decreases as the states are distilled to better quality. The interplay of of these different rates sets limits on the achievable distillation and how quickly states converge to that limit.

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[SPA] Las disciplinas artísticas siempre han sido un campo tan beneficioso como poco utilizado en educación. En esta propuesta de taller de teatro musical en educación primaria se ha indagado en el mundo de la pedagogía teatral y su relación con la música y el juego como técnicas de transmisión de valores y desarrollo de aprendizajes. La puesta en práctica mediante el diseño e implementación de un taller por parte del mediador ha logrado que los alumnos muestren avances significativos en diversos campos como el autoconocimiento corporal o el descubrimiento de nuevos géneros musicales, además de favorecer a la dinámica grupal dentro y fuera del taller. De cara al futuro, este proceso ha abierto las puertas a nuevas propuestas en el ámbito de la dramatización infantil así como al interés formativo del propio educador.