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Benchmarking and incentive regulation of quality of service: an application to the UK electricity distribution utilities
Quality of service has emerged as an important issue in post-reform regulation of electricity distribution networks. Regulators have employed partial incentive schemes to promote cost saving, investment efficiency, and service quality. This paper presents a quality-incorporated benchmarking study of the electricity distribution utilities in the UK between 1991/92 and 1998/99. We calculate technical efficiency of the utilities using Data Envelopment Analysis technique and productivity change over time using quality-incorporated Malmquist indices. We find that cost efficient firms do not necessarily exhibit high service quality and that efficiency scores of cost-only models do not show high correlation with those of quality-based models. The results also show that improvements in service quality have made a significant contribution to the sector�s total productivity change. In addition, we show that integrating quality of service in regulatory benchmarking is preferable to cost-only approaches
Advanced control strategies toward achieving nearly-zero energy consumption in buildings
In this paper the main concept and results of the PEBBLE Project are presented: PEBBLE is an ongoing FP7
Project aiming at the development of advanced ICT tools to support the operation of nearly-zero- and positive energy buildings. In the design and operation of such buildings a pragmatic target is maximization of the actual net energy produced (NEP) by intelligently shaping demand to perform generation-consumption matching. With
the belief that maximization of the NEP for Positive-Energy Buildings is attained thru Better ControL decisions (PEBBLE), a control and optimization ICT methodology that combines model-based predictive control and cognitive-based adaptive optimization is presented. There are three essential ingredients to the PEBBLE system: a) thermal simulation models; b) sensors, actuators, and user interfaces; and c), generic control and optimization tools. The potential for energy savings using advanced control strategies is illustrated using simulation-based studies: there are significant benefits in terms of energy-performance of using advanced control strategies, compared to traditional rule-based ones. Ongoing work about demonstration and evaluation of the PEBBLE system in three real world buildings is described
Simulation-time reduction techniques for a retrofit planning tool
The design of retrofitted energy efficient buildings is
a promising option towards achieving a cost-effective
improvement of the overall building sector’s energy
performance. With the aim of discovering the best design
for a retrofitting project in an automatic manner,
a decision making (or optimization) process is usually
adopted, utilizing accurate building simulation
models towards evaluating the candidate retrofitting
scenarios. A major factor which affects the overall
computational time of such a process is the simulation
execution time. Since high complexity and prohibitive
simulation execution time are predominantly
due to the full-scale, detailed simulation, in this work,
the following simulation-time reduction methodologies
are evaluated with respect to accuracy and computational
effort in a test building: Hierarchical clustering;
Koopman modes; and Meta-models. The simplified
model that would be the outcome of these
approaches, can be utilized by any optimization approach
to discover the best retrofitting option
Influence of finite quark chemical potentials on the three flavor LOFF phase of QCD
We study in the Ginzburg-Landau approximation, the
Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of QCD with three flavors and one
plane wave, including terms of order O(1/mu). We show that the LOFF window is
slightly enlarged, and actually splits into two different regions, one
characterized by u-s and d-u pairings and the other with d-u pairs only.Comment: 8 pages, 3 figure
Ginzburg-Landau approach to the three flavor LOFF phase of QCD
We explore, using a Ginzburg-Landau expansion of the free energy, the
Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of QCD with three flavors, using
the NJL four-fermion coupling to mimic gluon interactions. We find that, below
the point where the QCD homogeneous superconductive phases should give way to
the normal phase, Cooper condensation of the pairs u-s and d-u is possible, but
in the form of the inhomogeneous LOFF pairing.Comment: 8 pages, 4 figures. Eq. (20) corrected. As a consequence figures have
been modified to show only the solution with parallel total momenta of the
us, ud pairs, as the other configurations are suppressed. Main conclusions of
the paper are unchange
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