8,627 research outputs found
On Clifford's theorem for singular curves
Let C be a 2-connected Gorenstein curve either reduced or contained in a
smooth algebraic surface and let S be a subcanonical cluster (i.e. a 0-dim
scheme such that the space H^0(C, I_S K_C) contains a generically invertible
section). Under some general assumptions on S or C we show that h^0(C, I_S K_C)
<= p_a(C) - deg (S)/2 and if equality holds then either S is trivial, or C is
honestly hyperelliptic or 3-disconnected. As a corollary we give a
generalization of Clifford's theorem for reduced curves
Masonry wall panels retrofitted with thermal-insulating GFRP-reinforced jacketing
Today there is a need to provide thermally efficient walls, while at the same time to increase the mechanical properties of old unreinforced masonry walls that will not require large amounts of energy in the retrofitting or deconstruction processes. To address this problem, this paper gives the results of shear tests carried out on masonry panels made of solid bricks retrofitted with a new technique based on the use of glass fiber-reinforced polymers (GFRP) grids inserted into a thermal insulating jacketing. This was made of different low-strength lime-based mortars. Tests were carried out in laboratory and results were used for the determination of the shear modulus and strength of the wall panels before and after the application of the GFRP reinforcement. Retrofitted panels exhibited a significant enhancement in the lateral capacity when compared to the control panels. The thermal performance of the proposed mortars was also investigated both with and without GFRP. Low values of thermal conductivity were found, especially for the samples with GFRP; a reduction of the thermal transmittance value in the 34–45 % range was also obtained by applying 45 mm layer of coating in conventional masonry walls
Multi-Criteria Optimal Planning for Energy Policies in CLP
In the policy making process a number of disparate and diverse issues such as
economic development, environmental aspects, as well as the social acceptance
of the policy, need to be considered. A single person might not have all the
required expertises, and decision support systems featuring optimization
components can help to assess policies. Leveraging on previous work on
Strategic Environmental Assessment, we developed a fully-fledged system that is
able to provide optimal plans with respect to a given objective, to perform
multi-objective optimization and provide sets of Pareto optimal plans, and to
visually compare them. Each plan is environmentally assessed and its footprint
is evaluated. The heart of the system is an application developed in a popular
Constraint Logic Programming system on the Reals sort. It has been equipped
with a web service module that can be queried through standard interfaces, and
an intuitive graphic user interface.Comment: Accepted at ICLP2014 Conference as Technical Communication, due to
appear in Theory and Practice of Logic Programming (TPLP
A SURVEY ON MACROECONOMIC DATA IN THE EUROZONE AND A CONTROL DASHBOARD MODEL BASED ON THE KAM AND NEKHOROSHEV THEOREMS AND THE HÉNON ATTRACTOR
Starting from the examination of the main macroeconomic parameters that have characterized the structure of the Eurozone in the last decade – and their systemization – our aim was to apply a model suitable for describing its dynamics. In particular, the Kolmogorov-Arnold-Moser theorem was adapted to the question, up to low level perturbations caused by negative economic conditions, the first symptoms of financial or exogenous crises, and other turbulence affecting the economy. We then applied Nekhoroshev's theorem to represent the phenomena characterized by the occurrence of stronger resonance as well as the reactions of the system to the control and recovery measures implemented by the ECB Governing Council.
The goal of the paper is to propose the adoption of a systemic stability planning and control dashboard – also suitable for the support and stimulation of growth cycles – with attention to optimal performance, which can be identified in compliance with (or restoration of) the macroeconomic trajectories determined in the model by the Hénon Attractor.
The proposed scheme may find useful application – both for evaluation and operational purposes – in the current period, characterized by the complex and compromised scenario brought about by the SARS-COVID2 pandemic emergency, which has obviously imposed structured measures to support the economy
Subgame-perfect equilibrium strategies for time-inconsistent recursive stochastic control problems
We study time-inconsistent recursive stochastic control problems. Since for
this class of problems classical optimal controls may fail to exist or to be
relevant in practice, we focus on subgame-perfect equilibrium policies. The
approach followed in our work relies on the stochastic maximum principle: we
adapt the classical spike variation technique to obtain a characterization of
equilibrium strategies in terms of a generalized second-order Hamiltonian
function defined through a pair of backward stochastic differential equations.
The theoretical results are applied in the financial field to finite horizon
investment-consumption policies with non-exponential actualization.Comment: arXiv admin note: substantial text overlap with arXiv:2105.0147
The canonical ring of a 3-connected curve
Let C be a projective curve either reduced with planar singularities or
contained in a smooth algebraic surface. We show that the canonical ring R(C,
\omega_C)= \oplus_{k \geq 0} H^0(C, \omega_C^k is generated in degree 1 if C is
3-connected and not (honestly) hyperelliptic; we show moreover that R(C,
L)=\oplus_{k \geq 0} H^0(C,L^k)$ is generated in degree 1 if C is reduced with
planar singularities and L is an invertible sheaf such that deg L_{|B} \geq
2p_a(B)+1 for every B \subseteq C
TArC: Incrementally and Semi-Automatically Collecting a Tunisian Arabish Corpus
This article describes the constitution process of the first
morpho-syntactically annotated Tunisian Arabish Corpus (TArC). Arabish, also
known as Arabizi, is a spontaneous coding of Arabic dialects in Latin
characters and arithmographs (numbers used as letters). This code-system was
developed by Arabic-speaking users of social media in order to facilitate the
writing in the Computer-Mediated Communication (CMC) and text messaging
informal frameworks. There is variety in the realization of Arabish amongst
dialects, and each Arabish code-system is under-resourced, in the same way as
most of the Arabic dialects. In the last few years, the focus on Arabic
dialects in the NLP field has considerably increased. Taking this into
consideration, TArC will be a useful support for different types of analyses,
computational and linguistic, as well as for NLP tools training. In this
article we will describe preliminary work on the TArC semi-automatic
construction process and some of the first analyses we developed on TArC. In
addition, in order to provide a complete overview of the challenges faced
during the building process, we will present the main Tunisian dialect
characteristics and their encoding in Tunisian Arabish.Comment: Paper accepted at the Language Resources and Evaluation Conference
(LREC) 202
Energy and Water Monitoring for a Large Social Housing Intervention in Northern Italy
In recent years, the awareness of the problem of the performance gap and rebound effect extends the interest in assessing the real operation of buildings, in assessing how buildings match users' needs once they are occupied, and in understanding how occupants' behavior affects the actual building performance. The paper discusses the case study and presents the results of a monitoring campaign of 2 years of occupancy of a large social housing intervention recently built near Milan, for a total of 152 flats. Data about the thermal energy consumption for heating and cooling, the domestic hot and cold water use, and the occupants' intervention on controlling devices are assessed and presented. The case study is representative of the actual design and construction of high-performing multi-family buildings in Italy. All the buildings are class A rated, very highly insulated, and ventilated with centralized mechanical ventilation systems with thermodynamic heat recovery. Centralized water-to-water heat pumps supply hot and refrigerated water for heating and cooling and domestic hot water as well. A building monitoring system is installed, able to track energy and water consumption, factors influencing the energy consumption not related to the building characteristics (weather data, operational setting) as well as the overall building performance data. The results show unexpected high energy and water consumption and moreover a large variability of the energy and water consumption pattern among the dwellings and between the years due to the significant influence of the occupants' behavior and habits
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