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A multicriteria method for a pluarality of deciders
No full textIn this technical report we present a multicriteria method for a plurality of deciders. The method is designed as a decision aiding tool to allow the deciders to rank the alternatives of a given set A according to the criteria of the set C so to define the set of the best alternatives.<br /
Relationship between wave reflection and renal damage in hypertensive patients
No full textOBJECTIVE: Arterial stiffening has harmful effects; peripheral pulse wave reflections deleteriously increase central pressure, but on the contrary they could also possibly be protective, as the pulse is transmitted to the microcirculation to a lesser extent. The aim of this study was, therefore, to explore the relationship between wave reflection and small vessel damage in the kidney.
METHODS: In 216 hypertensive patients, data on renal resistive index, obtained by Doppler ultrasound sampling of the interlobar arteries, as well as augmentation index (AIx) and carotid-to-femoral pulse wave velocity (PWV), were retrospectively analyzed. Reflection magnitude was computed through a triangular flow estimate.
RESULTS: AIx and reflection magnitude were positively correlated with resistive index; age, BMI, central pulse pressure, and cholesterol, but not AIx or reflection magnitude, were predictors of resistive index in multivariate analyses. Crossing tertiles of PWV and AIx, resistive index did not differ between patients with high AIx and low PWV (n=25; 0.632 (0.064)) and those with low AIx and high PWV (n=17; 0.645 (0.053)), despite a difference in reflection magnitude (74.9 (6.7) vs. 51.2 (7.3)%; P<0.001).
CONCLUSION: Pressure wave reflection is positively correlated with resistive index in a hypertensive population. No negative relationship was found even adjusting for confounders or when it was examined separately from the influence of arterial stiffness. These findings do not support the hypothesis of peripheral wave reflections having a significant protective role for the microcirculation of a low resistance vascular bed such as the kidney
Joint assignment, scheduling and routing models to Home Care optimization: a pattern based approach
No full textThe design of efficient Home Care Services is a quite recent and challenging problem motivated by the ever increasing age of population and the consequent need to reduce hospitalization costs. We are given a weekly planning horizon, a set of operators each characterized by a skill and a set of patients each requiring a set of visits also characterized by a skill. We propose an integrated model that jointly addresses the following problems: (i) the assignment of operators to patients guaranteeing the appropriate levels of skill; (ii) the scheduling of visits in the planning horizon; and (iii) the determination of a set of tours indicating the sequence of patients each operator must visit in every day of the week. Several variants of this model are investigated. All of them use the pattern as a key tool to formulate the problem. A pattern is an a priori given profile specifying a possible schedule for a given set of visits possibly characterized by differnt skills. Computational results on a set of real instances are analysed. They show that the selection of the pattern generation policy is crucial to solve large instances efficiently
A Condensed Representation of Almost Normal Matrices
No full textIn this paper we study the structure of almost normal matrices, that is the matrices for which there exists a rank-one matrix such that . Necessary and sufficient conditions for a matrix to belong to the class are given and a canonical representation as a block tridiagonal matrix is shown. The approach is constructive and in the paper it is explained how, starting from a or matrix we can generate almost normal matrices. Moreover, given an almost normal matrix we can compute the block tridiagonal representation with a finite procedure.<br /
Sviluppo di un sistema di fresatura elettrochimica
No full textSUMMARY eport of the work done in association with Glasgow Caledonian University and it is about designing and developing of a non‐conventional machining system aimed
on using electro chemical reactions for milling processes, called Electrochemical Milling System (ECMIL).
This represents an evolution of an existing process, never developed because of several technical problems.
The aim of the thesis is demonstrating process feasibility by experimental tests and build up bases for process improvement.
Tests had been made using a simple and cheap system comparing to the classic ECM process.
The tool had been moved in one unique direction, saving its handling on a plane for future works.
Satisfying results had been obtained, though used machining parameters are different to the calculated ones; this is mainly caused by the way the electrolyte passed through the working area, allowing a not proper current transfer.
This last aspect future works will focus on
Horizontal rotation signals detected by "G-Pisa" ring laser for the Mw=9.0, March 2011, Japan earthquake
No full textWe report the observation of the ground rotation induced by the Mw=9.0, 11th
of March 2011, Japan earthquake. The rotation measurements have been conducted
with a ring laser gyroscope operating in a vertical plane, thus detecting
rotations around the horizontal axis. Comparison of ground rotations with
vertical accelerations from a co-located force-balance accelerometer shows
excellent ring laser coupling at periods longer than 100s. Under the plane wave
assumption, we derive a theoretical relationship between horizontal rotation
and vertical acceleration for Rayleigh waves. Due to the oblique mounting of
the gyroscope with respect to the wave direction-of-arrival, apparent
velocities derived from the acceleration / rotation rate ratio are expected to
be always larger than, or equal to the true wave propagation velocity. This
hypothesis is confirmed through comparison with fundamental-mode, Rayleigh wave
phase velocities predicted for a standard Earth model
Quantum driving protocols for a two level system: from generalized Landau-Zener sweeps to superadiabatic control
No full textSUMMARY We present experimental results on the preparation of a desired quantum state
in a two-level system with the maximum possible fidelity using driving
protocols ranging from generalizations of the linear Landau-Zener protocol to
transitionless driving protocols that ensure perfect following of the
instantaneous adiabatic ground state. We also study the minimum time needed to
achieve a target fidelity and explore and compare the robustness of some of the
protocols against parameter variations simulating a possible experimental
uncertainty. In our experiments, we realize a two-level model system using
Bose-Einstein condensates inside optical lattices, but the results of our
investigation should hold for any quantum system that can be approximated by a
two-level system
Theta dependence of the deconfinement temperature in Yang-Mills theories
No full textWe determine the theta dependence of the deconfinement temperature of SU(3)
pure gauge theory, finding that it decreases in presence of a topological theta
term. We do that by performing lattice simulations at imaginary theta, then
exploiting analytic continuation. We also give an estimate of such dependence
in the limit of a large number of colors N, and compare it with our numerical
results
Bott-Chern cohomology of solvmanifolds
No full textWe study conditions under which sub-complexes of a double complex of vector
spaces allow to compute the Bott-Chern cohomology. We are especially aimed at
studying the Bott-Chern cohomology of a special class of solvmanifolds
Degree of non-Kählerianity for 6-dimensional nilmanifolds
No full textWe use Bott-Chern cohomology to measure the non-K\"ahlerianity of
6-dimensional nilmanifolds endowed with the left-invariant complex structures
in M. Ceballos, A. Otal, L. Ugarte, and R. Villacampa's classification,
[Classification of complex structures on 6-dimensional nilpotent Lie algebras,
arXiv:1111.5873v4 [math.DG]]. We investigate the existence of pluriclosed
metric in connection with such a classification