115 research outputs found
Universal conductance enhancement and reduction of the two-orbital Kondo effect
We investigate theoretically the linear and nonlinear conductance through a
nanostructure with two-fold degenerate single levels, corresponding to the
transport through nanostructures such as a carbon nanotube, or double dot
systems with capacitive interaction. It is shown that the presence of the
interaction asymmetry between orbits/dots affects significantly the profile of
the linear conductance at finite temperature, and, of the nonlinear
conductance, particularly around half-filling, where the two-particle Kondo
effect occurs. Within the range of experimentally feasible parameters, the
SU(4) universal behavior is suggested, and comparison with relevant experiments
is made.Comment: 10 pages, 16 figure
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A semantic sensor web for environmental decision support applications
Sensing devices are increasingly being deployed to monitor the physical world around us. One class of application for which sensor data is pertinent is environmental decision support systems, e.g., flood emergency response. For these applications, the sensor readings need to be put in context by integrating them with other sources of data about the surrounding environment. Traditional systems for predicting and detecting floods rely on methods that need significant human resources. In this paper we describe a semantic sensor web architecture for integrating multiple heterogeneous datasets, including live and historic sensor data, databases, and map layers. The architecture provides mechanisms for discovering datasets, defining integrated views over them, continuously receiving data in real-time, and visualising on screen and interacting with the data. Our approach makes extensive use of web service standards for querying and accessing data, and semantic technologies to discover and integrate datasets. We demonstrate the use of our semantic sensor web architecture in the context of a flood response planning web application that uses data from sensor networks monitoring the sea-state around the coast of England
The implications of service quality gaps for strategy implementation
This article addresses the problem of service quality strategy implementation and
proposes three interrelated models: a static model of the organisation; a comprehensive
dynamic model of the implementation process, both synthesised from the literature; and
a mixed model, which integrates static and dynamic models. The mixed model is
combined with the service quality gaps (SQGs) model, drawn at a previous congress
paper, to propose a map of the pattern of SQGs occurring at each implementation stage;
the organisational variables that can be manipulated to eliminate SQGs; and several
implications to practising managers
The numerical renormalization group method for quantum impurity systems
In the beginning of the 1970's, Wilson developed the concept of a fully
non-perturbative renormalization group transformation. Applied to the Kondo
problem, this numerical renormalization group method (NRG) gave for the first
time the full crossover from the high-temperature phase of a free spin to the
low-temperature phase of a completely screened spin. The NRG has been later
generalized to a variety of quantum impurity problems. The purpose of this
review is to give a brief introduction to the NRG method including some
guidelines of how to calculate physical quantities, and to survey the
development of the NRG method and its various applications over the last 30
years. These applications include variants of the original Kondo problem such
as the non-Fermi liquid behavior in the two-channel Kondo model, dissipative
quantum systems such as the spin-boson model, and lattice systems in the
framework of the dynamical mean field theory.Comment: 55 pages, 27 figures, submitted to Rev. Mod. Phy
Crise de abastecimento de ågua em São Paulo e falta de planejamento estratégico
Embora a crise no abastecimento de ĂĄgua na RegiĂŁo Metropolitana de SĂŁo Paulo (RMSP) tenha se manifestado de maneira mais intensa no verĂŁo de 2013-2014, ela revela um problema crĂŽnico que vem afetando toda a RegiĂŁo nos Ășltimos dez anos. Esse problema foi gerado pela falta de um planejamento estratĂ©gico que considere questĂ”es climatolĂłgicas que podem indicar, com meses de antecedĂȘncia, problemas de recomposição dos nĂveis dos mananciais, permitindo que açÔes sejam empreendidas com razoĂĄvel antecedĂȘncia, reduzindo os impactos para a população. Este estudo mostra como Ă© possĂvel utilizar informaçÔes climĂĄticas na gestĂŁo estratĂ©gica do sistema de abastecimento da RMSP.Though the crisis in the water supplying system in the Metropolitan Region of SĂŁo Paulo (RMSP) was more intensively felt in the 2013-2014 summer, it reveals a chronic problem that has been affecting the whole RMSP for the past ten years. This problem is originated from the lack of a strategic planning that takes into consideration climate issues that could, months before, foresee problems to restore the levels of water resources, allowing measures to be implemented within a reasonable anticipation, therefore reducing the impacts on the population. This study shows how it is possible to use climate information in the strategic management of the water supply in the RMSP
âItâs Like Hating Puppies!â Employee Disengagement and Corporate Social Responsibility
Corporate social responsibility (CSR) has been linked with numerous organizational advantages, including recruitment, retention, productivity, and morale, which relate specifically to employees. However, despite specific benefits of CSR relating to employees and their importance as a stakeholder group, it is noteworthy that a lack of attention has been paid to the individual level of analysis with CSR primarily being studied at the organizational level. Both research and practice of CSR have largely treated the individual organization as a âblack box,â failing to account for individual differences amongst employees and the resulting variations in antecedents to CSR engagement or disengagement. This is further exacerbated by the tendency in stakeholder theory to homogenize priorities within a single stakeholder group. In response, utilizing case study data drawn from three multinational tourism and hospitality organizations, combined with extensive interview data collected from CSR leaders, industry professionals, engaged, and disengaged employees, this exploratory research produces a finer-grained understanding of employees as a stakeholder group, identifying a number of opportunities and barriers for individual employee engagement in CSR interventions. This research proposes that employees are situated along a spectrum of engagement from actively engaged to actively disengaged. While there are some common drivers of engagement across the entire spectrum of employees, differences also exist depending on the degree to which employees, rather than senior management, support corporate responsibility within their organizations. Key antecedents to CSR engagement that vary depending on employeesâ existing level of broader engagement include organizational culture, CSR intervention design, employee CSR perceptions, and the observed benefits of participation
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