926 resultados para State-based Specifications
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merged beam technique has been used to investigate the fragmentation of the Cl ion in collisions with electrons over an energy range of 0–200 eV. We have measured absolute cross sections for detachment, detachment plus dissociation and dissociation processes. Over the energy range studied, the dominant breakup mechanism is dissociation. Dissociation is relatively enhanced in the e–+Cl collision system due to the suppression of the normally dominant detachment process, as a result of the large difference between the equilibrium internuclear distances of the Cl2 and Cl ground state potential curves. A prominent structure is observed just above the threshold in the Cl–+Cl+e– dissociation channel. It is proposed that the structure is a resonance associated with production and rapid decay of an excited state of the doubly charged Cl ion. A plausible mechanism for production of the di-anionic state based on an excitation plus capture process is suggested.
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A BSP superstep is a distributed computation comprising a number of simultaneously executing processes which may generate asynchronous messages. A superstep terminates with a barrier which enforces a global synchronisation and delivers all ongoing communications. Multilevel supersteps can utilise barriers in which subsets of processes, interacting through shared memories, are locally synchronised (partitioned synchronisation). In this paper a state-based semantics, closely related to the classical sequential programming model, is derived for distributed BSP with partitioned synchronisation.
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We show that the use of probabilistic noiseless amplification in entangled coherent state-based schemes for the test of quantum nonlocality provides substantial advantages. The threshold amplitude to falsify a Bell-CHSH nonlocality test, in fact, is significantly reduced when amplification is embedded into the test itself. Such a beneficial effect holds also in the presence of detection inefficiency. Our study helps in affirming noiseless amplification as a valuable tool for coherent information processing and the generation of strongly nonclassical states of bosonic systems.
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Raman spectra in the range of the totally symmetric stretching mode of the [PF6]− anion, νs(PF6), have been measured for 1-alkyl-3-methylimidazolium ionic liquids [CnC1im][PF6], for n = 4, 6, and 8, as a function of pressure at room temperature. The ionic liquids [C6C1im][PF6] and [C8C1im][PF6] remain in an amorphous phase up to 3.5 GPa, in contrast to [C4C1im][PF6], whichcrystallizes above ∼0.5 GPa. Equations of state based either on a group contribution model or Carnahan-Starling-van der Waals model have been used to estimate the densities of the ionic liquids at high pressures. The shifts of the vibrational frequency of νs(PF6) with density observed in [C6C1im][PF6] and in [C8C1im][PF6] have been calculated by a hard-sphere model of a pseudo-diatomic solute under short-range repulsive interactions with the neighboring particles. The stochastic model of Kubo for vibrational dephasing has been used to obtain the amplitude of vibrational frequency fluctuation, ⟨Δω 2⟩, and the relaxation time of frequency fluctuation, τ c , as a function of density by Raman band shape analysis of the νs(PF6) mode of [C6C1im][PF6] and [C8C1im][PF6].
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Inorganica Chimica Acta 356 (2003) 215-221
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Dissertação para obtenção do Grau de Doutor em Engenharia Informática
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The nonforgetting restarting automaton is a generalization of the restarting automaton that, when executing a restart operation, changes its internal state based on the current state and the actual contents of its read/write window instead of resetting it to the initial state. Another generalization of the restarting automaton is the cooperating distributed system (CD-system) of restarting automata. Here a finite system of restarting automata works together in analyzing a given sentence, where they interact based on a given mode of operation. As it turned out, CD-systems of restarting automata of some type X working in mode =1 are just as expressive as nonforgetting restarting automata of the same type X. Further, various types of determinism have been introduced for CD-systems of restarting automata called strict determinism, global determinism, and local determinism, and it has been shown that globally deterministic CD-systems working in mode =1 correspond to deterministic nonforgetting restarting automata. Here we derive some lower bound results for some types of nonforgetting restarting automata and for some types of CD-systems of restarting automata. In this way we establish separations between the corresponding language classes, thus providing detailed technical proofs for some of the separation results announced in the literature.
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A limitation of small-scale dairy systems in central Mexico is that traditional feeding strategies are less effective when nutrient availability varies through the year. In the present work, a linear programming (LP) model that maximizes income over feed cost was developed, and used to evaluate two strategies: the traditional one used by the small-scale dairy producers in Michoacan State, based on fresh lucerne, maize grain and maize straw; and an alternative strategy proposed by the LIP model, based on ryegrass hay, maize silage and maize grain. Biological and economic efficiency for both strategies were evaluated. Results obtained with the traditional strategy agree with previously published work. The alternative strategy did not improve upon the performance of the traditional strategy because of low metabolizable protein content of the maize silage considered by the model. However, the Study recommends improvement of forage quality to increase the efficiency of small-scale dairy systems, rather than looking for concentrate supplementation.
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This article considers whether, in the context of armed conflicts, certain non-refoulement obligations of non-belligerent States can be derived from the 1949 Geneva Conventions. According to Common Article 1 (CA1) thereof, all High Contracting Parties (HCPs) undertake to ‘respect and to ensure respect’ for the four conventions ‘in all circumstances’. It is contended that CA1 applies both in international armed conflicts (IACs) and in non-international armed conflicts (NIACs). In turn, it is suggested that Common Article 3 (CA3) which regulates conduct in NIACs serves as a ‘minimum yardstick’ also applicable in IACs. It is widely (though not uniformly) acknowledged that the undertaking to ‘ensure respect’ in a given armed conflict extends to HCPs that are not parties to it; nevertheless, the precise scope of this undertaking is subject to scholarly debate. This article concerns situations where, in the course of an (international or non-international) armed conflict, persons ’taking no active part in hostilities’ flee from States where violations of CA3 are (likely to be) occurring to a non-belligerent State. Based on the undertaking in CA1, the central claim of this article is that, as long as risk of exposure to these violations persists, persons should not be refouled notwithstanding possible assessment of whether they qualify as refugees based on the 1951 Refugee Convention definition, or could be eligible for complementary or subsidiary forms of protection that are regulated in regional arrangements. The analysis does not affect the explicit protection from refoulement that the Fourth Geneva Convention accords to ‘protected persons’ (as defined in Article 4 thereof). It is submitted that CA1 should be read in tandem with other obligations of non-belligerent States under the 1949 Geneva Conventions. Most pertinently, all HCPs are required to take specific measures to repress ‘grave breaches’ and to take measures necessary for the suppression of all acts contrary to the 1949 Geneva Conventions other than the grave breaches. A HCP that is capable of protecting displaced persons from exposure to risks of violations of CA3 and nonetheless refoules them to face such risks is arguably failing to take lawful measures at its disposal in order to suppress acts contrary to the conventions and, consequently, fails to ‘ensure respect’ for the conventions. KEYWORDS Non-refoulement; International Armed Conflict; Non-International Armed Conflict; Common Article 1; Common Article 3
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The aim of this preliminary work was to present a novel method, suitable to investigate the glass cooling, from melt to solid state, based on a fast, non-usual and easy microwave method. The following glass system xBaO . (100-x)B(2)O(3) (x = 0% and 40%) was selected as an example for this study. The melt was poured inside a piece of waveguide and then, its cooling was monitored by the microwave signal as a function of time. The variations in the signal can provide valuable informations about some structural changes that take place during the cooling stages, such as relaxation processes. This method can be useful to investigate the cooling and heating of other materials, opening new possibilities for investigation of dielectric behavior of materials under high temperatures. (C) 2008 Elsevier Inc. All rights reserved.
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In this paper, we consider a classical problem of complete test generation for deterministic finite-state machines (FSMs) in a more general setting. The first generalization is that the number of states in implementation FSMs can even be smaller than that of the specification FSM. Previous work deals only with the case when the implementation FSMs are allowed to have the same number of states as the specification FSM. This generalization provides more options to the test designer: when traditional methods trigger a test explosion for large specification machines, tests with a lower, but yet guaranteed, fault coverage can still be generated. The second generalization is that tests can be generated starting with a user-defined test suite, by incrementally extending it until the desired fault coverage is achieved. Solving the generalized test derivation problem, we formulate sufficient conditions for test suite completeness weaker than the existing ones and use them to elaborate an algorithm that can be used both for extending user-defined test suites to achieve the desired fault coverage and for test generation. We present the experimental results that indicate that the proposed algorithm allows obtaining a trade-off between the length and fault coverage of test suites.
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During the latest decade Somali-born women with experiences of long-lasting war followed by migration have increasingly encountered Swedish maternity care, where antenatal care midwives are assigned to ask questions about exposure to violence. The overall aim in this thesis was to gain deeper understanding of Somali-born women’s wellbeing and needs during the parallel transitions of migration to Sweden and childbearing, focusing on maternity healthcare encounters and violence. Data were obtained from medical records (paper I), qualitative interviews with Somali-born women (II, III) and Swedish antenatal care midwives (IV). Descriptive statistics and thematic analysis were used. Compared to pregnancies of Swedish-born women, Somali-born women’s pregnancies demonstrated later booking and less visits to antenatal care, more maternal morbidity but less psychiatric treatment, less medical pain relief during delivery and more emergency caesarean sections and small-for-gestational-age infants (I). Political violence with broken societal structures before migration contributed to up-rootedness, limited healthcare and absent state-based support to women subjected to violence, which reinforced reliance on social networks, own endurance and faith in Somalia (II). After migration, sources of wellbeing were a pragmatic “moving-on” approach including faith and motherhood, combined with social coherence. Lawful rights for women were appreciated but could concurrently risk creating power tensions in partner relationships. Generally, the Somali-born women associated the midwife more with providing medical care than with overall wellbeing or concerns about violence, but new societal resources were parallel incorporated with known resources (III). Midwives strived for woman-centered approaches beyond ethnicity and culture in care encounters, with language, social gaps and divergent views on violence as potential barriers in violence inquiry. Somali-born women’s strength and contentment were highlighted, and ongoing violence seldom encountered according to the midwives experiences (IV). Pragmatism including “moving on” combined with support from family and social networks, indicate capability to cope with violence and migration-related stress. However, this must be balanced against potential unspoken needs at individual level in care encounters.With trustful relationships, optimized interaction and networking with local Somali communities and across professions, the antenatal midwife can have a “bridging-function” in balancing between dual societies and contribute to healthy transitions in the new society.
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The Delaware River provides half of New York City's drinking water, is a habitat for wild trout, American shad and the federally endangered dwarf wedge mussel. It has suffered four 100‐year floods in the last seven years. A drought during the 1960s stands as a warning of the potential vulnerability of the New York City area to severe water shortages if a similar drought were to recur. The water releases from three New York City dams on the Delaware River's headwaters impact not only the reliability of the city’s water supply, but also the potential impact of floods, and the quality of the aquatic habitat in the upper river. The goal of this work is to influence the Delaware River water release policies (FFMP/OST) to further benefit river habitat and fisheries without increasing New York City's drought risk, or the flood risk to down basin residents. The Delaware water release policies are constrained by the dictates of two US Supreme Court Decrees (1931 and 1954) and the need for unanimity among four states: New York, New Jersey, Pennsylvania, and Delaware ‐‐ and New York City. Coordination of their activities and the operation under the existing decrees is provided by the Delaware River Basin Commission (DRBC). Questions such as the probability of the system approaching drought state based on the current FFMP plan and the severity of the 1960s drought are addressed using long record paleo‐reconstructions of flows. For this study, we developed reconstructed total annual flows (water year) for 3 reservoir inflows using regional tree rings going back upto 1754 (a total of 246 years). The reconstructed flows are used with a simple reservoir model to quantify droughts. We observe that the 1960s drought is by far the worst drought based on 246 years of simulations (since 1754).
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This work aimed to study the structure and dynamic of Phytoplankton and Bacterioplankton in a complete cycle of shrimp cultivation (Litopenaeus vannamei) and determine the environmental factors responsible for the structural changes of these communities. The study was realized in a saltwater shrimp farm (Macaíba, RN), between September/2005 and February/2006, and in a freshwater shrimp farm (Ceará Mirim, RN), between May/2007 and September 2007. The samplings were collected weekly in saltwater farm and every fifteen days in freshwater farm. Total phosphorus, chlorophyll a and environmental parameters (pH, dissolved oxygen, salinity, temperature, depth and water transparency) were measured. Qualitative and quantitative analysis of the phytoplankton and bacterioplankton were carried out. The Shannon-Wiener ecologic indexes of diversity and the Pielou equitability indexes were calculated to the phytoplankton. Bacterial density was determined by epifluorescence microscopy. The data were statistically analyzed by Pearson correlation and t-Test. Chlorophycea were predominat in salt water and in the captation/drainage point (24 to 99%). Diatoms had higher wealth. The species Choricystis minor had the highest occurrence (100%) and dominance (90-100%), thus showing its adaptation to the high temperatures, salinity and low water transparency conditions. Filamentous Cyanobacteria like Oscillatoria sp., Pseudoanabaena sp. and Phormidium sp. had constant levels. The negative correlation between chlorophycea and water transparency, and the positive correlation between chlorophyll a and salinity, showed that the phytoplankton was well adapted to the low transparency and to the high salinity. The bacterioplankton was negatively correlated with the total phosphorus and salinity. In freshwater, Cyanobacteria were predominant (>80%), presenting some producers of toxins species like Microcystis sp., Aphanizomenon sp., Cylindrospermopsis raciborskii e Anabaena circinalis. Cyanobacterial density and total phosphorus and chlorophyll a concentrations exceeded the maximum value allowed by legislation. The means of total phosphorus varied from 264 to 627 Wg.L-1 and the means of chlorophyll a oscillated between 22 and 182 Wg.L-1. The phytoplankton species were selected by low availability of the light, high pH, temperature and high availability of total phosphorus. The bacterioplankton showed high densities (5,13 x 107 to 8,50 x107 Bac.mL-1). The studied environments (ponds and rivers) presented a high level of trophic state based on the high concentrations of chlorophyll a and total phosphorus and cyanobacteria dominance. The composition of species in the ponds and rivers was similar, as well as high concentrations of total phosphorus and chlorophyll a, highlighting the pollution caused by the discharges of the farms in natural environment
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The administrative model of the Brazilian State, based on regulation, strives, with the application of the efficiency principle and assessment of economical costs, to give a greater effectiveness to fundamental rights by implementing public policies.The objective of this work is to analyze the role of Oil royalties in the context of the Brazilian State, considering that, being an income gap, they might work as a device that promotes intra/intergenerational justice. By means of a correct and efficient distribution and application in the national region, the royalties constitute financial resources available for implementing public policies that intend to guarantee the fundamental rights; above all, with the discovery of the Pre-salt basin and the indisputable rise in the tax revenues arising from Oil exploration. In the making of this work, the theoretical-descriptive methodology is observed, grounded in a critical-reflexive analysis about Constitutional Law and Oil Law. This work analyzes the administrative model of the Brazilian State, the theory of costs of fundamental rights and the theoretical aspects about royalties, such as: the ethical and economical fundamentals, the distribution and destination of revenues, considering the oil exploration scenario before and after the discovery of the pre-salt basin. it is verified, with the present work, the importance of the creation of a new regulatory framework, and consequently the creation of a sovereign wealth fund, which arises to re-evaluate the application of the current norms of Oil revenue distribution. Still, it is imperative that the mechanisms for controlling the application of royalties are defined in detail, so that those can fully admit the objectives of intra/intergenerational justice. Furthermore, it is emphasized that this process should develop from the efficiency principle viewpoint, as well as the principle of reducing social and regional differences, given that the Oil revenues might be used to ensure fundamental social rights, by implementing public policies that are aligned with the development recommended by the Federal Constitution