974 resultados para continuous representations
Resumo:
We describe all two dimensional unital Riesz algebras and study representations of them in Riesz algebras of regular operators. Although our results are not complete, we do demonstrate that very varied behaviour can occur even though all these algebras can be given a Banach lattice algebra norm.
Resumo:
This paper proposes a continuous time Markov chain (CTMC) based sequential analytical approach for composite generation and transmission systems reliability assessment. The basic idea is to construct a CTMC model for the composite system. Based on this model, sequential analyses are performed. Various kinds of reliability indices can be obtained, including expectation, variance, frequency, duration and probability distribution. In order to reduce the dimension of the state space, traditional CTMC modeling approach is modified by merging all high order contingencies into a single state, which can be calculated by Monte Carlo simulation (MCS). Then a state mergence technique is developed to integrate all normal states to further reduce the dimension of the CTMC model. Moreover, a time discretization method is presented for the CTMC model calculation. Case studies are performed on the RBTS and a modified IEEE 300-bus test system. The results indicate that sequential reliability assessment can be performed by the proposed approach. Comparing with the traditional sequential Monte Carlo simulation method, the proposed method is more efficient, especially in small scale or very reliable power systems.
Resumo:
Despite the numerous advantages of continuous processing, high-value chemical production is still dominated by batch techniques. In this paper, we investigate options for the continuous dehydrogenation of 1,2,3,4- tetrahydrocarbazole using a trickle bed reactor operating under realistic liquid velocities with and without the addition of a hydrogen acceptor. Here, a commercial 5 wt % Pd/Al2O3 catalyst was observed to slowly deactivate, hence proving unsuitable for continuous use. This deactivation was attributed to the strong adsorption of a byproduct on the surface of the support. Application of a base washing technique resolved this issue and a stable continuous reaction has been demonstrated. As was previously shown for the batch reaction, the addition of a hydrogen acceptor gas (propene) can increase the overall catalytic activity of the system.
Resumo:
This paper presents a multimodal analysis of online self-representations of the Elite Squad of the military police of Rio de Janeiro, the Special Police Operations Battalion BOPE. The analysis is placed within the wider context of a “new military urbanism”, which is evidenced in the ongoing “Pacification” of many of the city’s favelas, in which BOPE plays an active interventionist as well as a symbolic role, and is a kind of solution which clearly fails to address the root causes of violence which lie in poverty and social inequality. The paper first provides a sociocultural account of BOPE’s role in Rio’s public security and then looks at some of the mainly visual mediated discourses the Squad employs in constructing a public image of itself as a modern and efficient, yet at the same time “magical” police force.
Resumo:
Purpose - The purpose is to unearth managerial representations of achieving competitive advantage in relation to architectural firms operating within the United Kingdom (UK).
Design/Methodology/Approach - A sequential qualitative methodology is applied, underpinned by nine managerial interviews in five architectural practices; all of which are analysed using computer assisted qualitative data analysis software.
Findings - 108 representations are identified with highly rated concepts discussed in detail. Subsequently, the leading concepts include reputation, client satisfaction, fees and staff resources, among others.
Research Limitations/Implications - There are numerous studies conducted on this subject; however, there has been no research done to date documenting managerial representations within the UK on achieving competitive advantage in the context of architectural firms.
Practical Implications – The need for architectural firms to develop a competitive advantage within their market sector is ever more apparent, particularly during times of increased competitiveness.
Originality/Value – This paper fulfils a gap in knowledge by contributing to underlying research on the subject of competitive advantage, but focusing on the managerial representations, specifically within UK practices. The findings are of relevance to architects in both the UK and beyond, as well as perhaps forming the basis of identifying further research with the area.
Resumo:
This study evaluated the effect of an industrial scale continuous flow microwave volumetric heating system in comparison to conventional commercial scale pasteurisation for the processing of tomato juice in terms of physicochemical properties, microbial characteristics and antioxidant capacity. The effect against oxidative stress in Caco-2 cells, after in vitro digestion was also investigated. Physicochemical and colour characteristics of juices were very similar between technologies and during storage. Both conventional and microwave pasteurisation inactivated microorganisms and kept them in low levels throughout storage. ABTS+ values, but not ORAC, were higher for the microwave pasteurised juice at day 0 however no significant differences between juices were observed during storage. Juice processed with the microwave system showed an increased cytoprotective effect against H2O2 induced oxidation in Caco-2 cells. Organoleptic analysis revealed that the two tomato juices were very similar. The continuous microwave volumetric heating system appears to be a viable alternative to conventional pasteurisation.
Resumo:
Acute respiratory infections are the leading cause of global child mortality. In the developing world, nasal oxygen therapy is often the only treatment option for babies who are suffering from respiratory distress. Without the added pressure of bubble Continuous Positive Airway Pressure (bCPAP) which helps maintain alveoli open, babies struggle to breathe and can suffer serious complications, and frequently death. A stand-alone bCPAP device can cost $6,000, too expensive for most developing world hospitals. Here, we describe the design and technical evaluation of a new, rugged bCPAP system that can be made in small volume for a cost-of-goods of approximately $350. Moreover, because of its simple design--consumer-grade pumps, medical tubing, and regulators--it requires only the simple replacement of a <$1 diaphragm approximately every 2 years for maintenance. The low-cost bCPAP device delivers pressure and flow equivalent to those of a reference bCPAP system used in the developed world. We describe the initial clinical cases of a child with bronchiolitis and a neonate with respiratory distress who were treated successfully with the new bCPAP device.
Resumo:
The practical knowledge has characteristics of a process with peculiar idiosyncrasies that require disruption with preconceived ideas, dialogue, negotiation and joint action. The knowledge underlying remains unclear despite of being what informs decision making. It is academia’s responsibility to unveil and nominate knowledge and that is the reason why we conducted two studies with clinical nurses. The aim is to understand the social representation that nurses make of their knowledge about nursing and analyze their clinical practices. In one of the studies, based on the theoretical-methodological referential of social representations, we used the technique of free association of words with the stimulus “knowledge in nursing”. In another study, developed within a naturalistic context and under the “Grounded Theory” referential, we used non-participative observation and explanatory interviews. From the first study we identified the structure of social representations of knowledge in nursing, from which emerged the central core constituted by four elements (Investigation, Wisdom, help Relation, Competence) and a second periphery with one element (Reflection). With the second study we identified that decisions are made within a dynamic, systematic and continuous process of diagnostic evaluation and clinical intervention using the various types of knowledge (e.g. clinic, experiential, scientific, personal). We concluded that the various types of knowledge in nursing, represented by the expressions mentioned above, are systematically and creatively mobilized within the dynamic process of diagnostic evaluation and clinical intervention. It is therefore important to unveil and nominate the different knowledge implicit in the clinical practice and Academia should be responsible for that task.
Resumo:
UNVEILING PROFESSIONAL KNOWLEDGES: A SCOPE OF HIGHER EDUCATION The practical knowledge has characteristics of a process with peculiar idiosyncrasies that require disruption with preconceived ideas, dialogue, negotiation and joint action. The knowledge underlying remains unclear despite of being what informs decision making. It is academia’s responsibility to unveil and nominate knowledge and that is the reason why we conducted two studies with clinical nurses. The aim is to understand the social representation that nurses make of their knowledge about nursing and analyze their clinical practices. In one of the studies, based on the theoretical-methodological referential of social representations, we used the technique of free association of words with the stimulus “knowledge in nursing”. In another study, developed within a naturalistic context and under the “Grounded Theory” referential, we used non-participative observation and explanatory interviews. From the first study we identified the structure of social representations of knowledge in nursing, from which emerged the central core constituted by four elements (Investigation, Wisdom, help Relation, Competence) and a second periphery with one element (Reflection). With the second study we identified that decisions are made within a dynamic, systematic and continuous process of diagnostic evaluation and clinical intervention using the various types of knowledge (e.g. clinic, experiential, scientific, personal). We concluded that the various types of knowledge in nursing, represented by the expressions mentioned above, are systematically and creatively mobilized within the dynamic process of diagnostic evaluation and clinical intervention. It is therefore important to unveil and nominate the different knowledge implicit in the clinical practice and Academia should be responsible for that task.
Resumo:
The modulation of neural activity in visual cortex is thought to be a key mechanism of visual attention. The investigation of attentional modulation in high-level visual areas, however, is hampered by the lack of clear tuning or contrast response functions. In the present functional magnetic resonance imaging study we therefore systematically assessed how small voxel-wise biases in object preference across hundreds of voxels in the lateral occipital complex were affected when attention was directed to objects. We found that the strength of attentional modulation depended on a voxel's object preference in the absence of attention, a pattern indicative of an amplificatory mechanism. Our results show that such attentional modulation effectively increased the mutual information between voxel responses and object identity. Further, these local modulatory effects led to improved information-based object readout at the level of multi-voxel activation patterns and to an increased reproducibility of these patterns across repeated presentations. We conclude that attentional modulation enhances object coding in local and distributed object representations of the lateral occipital complex.
Resumo:
Object categorisation is linked to detection, segregation and recognition. In the visual system, these processes are achieved in the ventral \what"and dorsal \where"pathways [3], with bottom-up feature extractions in areas V1, V2, V4 and IT (what) in parallel with top-down attention from PP via MT to V2 and V1 (where). The latter is steered by object templates in memory, i.e. in prefrontal cortex with a what component in PF46v and a where component in PF46d.