672 research outputs found
A Branch-and-Price Algorithm for the Electric Autonomous Dial-A-Ride Problem
The Electric Autonomous Dial-A-Ride Problem (E-ADARP) consists in scheduling
a fleet of electric autonomous vehicles to provide ride-sharing services for
customers that specify their origins and destinations. The E-ADARP differs from
the classical DARP in two aspects: (i) a weighted-sum objective that minimizes
both total travel time and total excess user ride time; (ii) the employment of
electric autonomous vehicles and a partial recharging policy. This paper
presents a highly-efficient labeling algorithm, which is integrated into
Branch-and-Price (B&P) algorithms to solve the E-ADARP. To handle (i), we
introduce a fragment-based representation of paths. A novel approach is invoked
to abstract fragments to arcs while ensuring excess-user-ride-time optimality.
We then construct a new graph that preserves all feasible routes of the
original graph by enumerating all feasible fragments, abstracting them to arcs,
and connecting them with each other, depots, and recharging stations in a
feasible way. On the new graph, partial recharging (ii) is tackled exactly by
tailored Resource Extension Functions (REFs). We apply strong dominance rules
and constant-time feasibility checks to compute the shortest paths efficiently.
These methods construct the first labeling algorithm that can deal with
minimizing (excess) user ride time. In the computational experiments, the B&P
algorithm achieves optimality in 71 out of 84 instances. Remarkably, among
these instances, 50 were solved optimally at the root node without branching.
We identify 26 new best solutions, improve 30 previously reported lower bounds,
and provide 17 new lower bounds for large-scale instances with up to 8 vehicles
and 96 requests. In total 42 new best solutions are generated on previously
solved and unsolved instances
ОБСЛУГОВУВАННЯ ЧИТАЧІВ У БІБЛІОТЕКАХ НАВЧАЛЬНИХ ЗАКЛАДІВ ДОРЕВОЛЮЦІЙНОГО КАТЕРИНОСЛАВА
Висвітлено історичний розвиток бібліотек навчальних закладів краю, приділена увага
процесу обслуговування читацького контингенту освітніх закладів, напрямкам, формам, та
характерним рисам. Визначено місце і роль бібліотечних працівників-викладачів.Historical development of educational institutions libraries of Yekaterinoslav region is shown,
special attentionis paidto readers’ service in national education, its trends,forms andpeculiar features.
The place and role of librarian teachers is defined
Parallax of PSR J1744-1134 and the Local Interstellar Medium
We present the annual trigonometric parallax of PSR J1744-1134 derived from
an analysis of pulse times of arrival. The measured parallax, pi = 2.8+/-0.3
mas ranks among the most precisely determined distances to any pulsar. The
parallax distance of 357+/-39 pc is over twice that derived from the dispersion
measure using the Taylor & Cordes model for the Galactic electron distribution.
The mean electron density in the path to the pulsar, n_e = (0.0088 +/- 0.0009)
cm^{-3}, is the lowest for any disk pulsar. We have compared the n_e for PSR
J1744-1134 with those for another 11 nearby pulsars with independent distance
estimates. We conclude that there is a striking asymmetry in the distribution
of electrons in the local interstellar medium. The electron column densities
for pulsars in the third Galactic quadrant are found to be systematically
higher than for those in the first. The former correlate with the position of
the well known local HI cavity in quadrant three. The excess electrons within
the cavity may be in the form of HII clouds marking a region of interaction
between the local hot bubble and a nearby superbubble.Comment: revised version accepted for publication in ApJ Letters; reanalysis
of uncertainty in parallax measure and changes to fig
Syphilis infection is associated with an increase in plasma viral load in HIV infected patients: results from the FHDH cohort — ANRS CO4
International audiencen.
Dealing Automatically with Exceptions by Introducing Specificity in ASP
Answer Set Programming (ASP), via normal logic programs, is known as a suitable framework for default reasoning since it offers both a valid formal model and operational systems. However, in front of a real world knowledge representation problem, it is not easy to represent information in this framework. That is why the present article proposed to deal with this issue by generating in an automatic way the suitable normal logic program from a compact representation of the information. This is done by using a method, based on specificity, that has been developed for default logic and which is adapted here to ASP both in theoretical and practical points of view
Risk of malignant lymphoma associated with human herpesvirus-8: a case–control study in Spain
No overall increased risk of lymphoma associated with antibodies to human herpesvirus-8 was found in 526 lymphomas and 599 controls (odds ratio (OR)=1.04, 95% confidence interval (CI)=0.62-1.75); significant increases were noted for 19 lymphoplasmacytic lymphomas (OR=4.47, 95% CI=1.34-14.85) and nine low-grade lymphoma/lymphoma B-cell NOS (OR=5.82, 95% CI=1.07-31.73)
Modelling the sigma phase
39th Edition of the Joint European Days on Equilibrium between Phases (JEEP), Nancy, FRANCE, MAR 19-21, 2013International audienceno abstrac
Antitumour necrosis factor-α therapy for hidradenitis suppurativa: results from a national cohort study between 2000 and 2013
International audienceHidradenitis suppurativa (HS) is a frequent chronic inflammatory skin disease typically characterized by recurrent painful, deep inflammatory nodules of the axillary, breast, groin and gluteal areas. European recommendations are mainly based on expert opinion. Drug treatments are heterogenous (e.g., antibiotics, corticosteroids, retinoids) and lack consensus among expert centres. The most severe disease forms or those failing to respond to conventional drugs may be associated with worsened functional prognosis. Anti-tumor necrosis factor α (anti-TNFα) drugs have been prescribed in these cases. The results of randomized controlled trials (RCTs) are discordant. Three RCTs concluded to the efficacy of adalimumab (ADA), and two others did not detect any difference between infliximab (IFX) or etanercept (ETA) and placebo. Finally, data from the literature and reported experiences do not conclude on the efficacy of anti-TNFα drugs for HS. This article is protected by copyright. All rights reserve
Dynamics of Fluid Vesicles in Oscillatory Shear Flow
The dynamics of fluid vesicles in oscillatory shear flow was studied using
differential equations of two variables: the Taylor deformation parameter and
inclination angle . In a steady shear flow with a low viscosity
of internal fluid, the vesicles exhibit steady tank-treading
motion with a constant inclination angle . In the oscillatory flow
with a low shear frequency, oscillates between or
around for zero or finite mean shear rate ,
respectively. As shear frequency increases, the vesicle
oscillation becomes delayed with respect to the shear oscillation, and the
oscillation amplitude decreases. At high with , another limit-cycle oscillation between and
is found to appear. In the steady flow, periodically rotates
(tumbling) at high , and and the vesicle shape
oscillate (swinging) at middle and high shear rate. In the
oscillatory flow, the coexistence of two or more limit-cycle oscillations can
occur for low in these phases. For the vesicle with a fixed shape,
the angle rotates back to the original position after an oscillation
period. However, it is found that a preferred angle can be induced by small
thermal fluctuations.Comment: 11 pages, 13 figure
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