Parallel drone scheduling vehicle routing problems with collective drones

We study last-mile delivery problems where trucks and drones collaborate to deliver goods to final customers. In particular, we focus on problem settings where either a single truck or a fleet with several homogeneous trucks work in parallel to drones, and drones have the capability of collaborating for delivering missions. This cooperative behaviour of the drones, which are able to connect to each other and work together for some delivery tasks, enhance their potential, since connected drone has increased lifting capabilities and can fly at higher speed, overcoming the main limitations of the setting where the drones can only work independently. In this work, we contribute a Constraint Programming model and a valid inequality for the version of the problem with one truck, namely the \emph{Parallel Drone Scheduling Traveling Salesman Problem with Collective Drones} and we introduce for the first time the variant with multiple trucks, called the \emph{Parallel Drone Scheduling Vehicle Routing Problem with Collective Drones}. For the latter variant, we propose two Constraint Programming models and a Mixed Integer Linear Programming model. An extensive experimental campaign leads to state-of-the-art results for the problem with one truck and some understanding of the presented models' behaviour on the version with multiple trucks. Some insights about future research are finally discussed

L'EVOLUZIONE DEL POTERE AEREO NEGLI SCENARI DEL TERZO MILLENNIO

2006/2007Nei 500 anni di storia che contraddistinguono la cosiddetta “Columbian Age” (1500 -1900) lo scenario geopolitico internazionale è caratterizzato in larga misura dal confronto tra potenze navali e potenze terrestri. La prevalente superiorità del potere navale, in particolare tra il XIX e l’inizio del XX Secolo, stimola, in particolar modo nella prima metà del Novecento, la nascita e l’evoluzione delle dottrine geopolitiche classiche che vedono i maggiori interpreti (Halford Mackinder, Alfred Mahan, Nicholas Spykman, Rudolf Kjellén, Karl Haushofer, Friedrich Ratzel) schierati su due fronti. E’un confronto tra mare e terra che vede nella conquista iniziale del dominio alternativamente sull’heartland o sul rimland le due differenti interpretazioni e scuole di pensiero (anglosassone e tedesca). Sono proprie queste dottrine geopolitiche che ispirano le scelte strategiche delle grandi potenze per tutto il secolo appena trascorso, condizionando le due guerre mondiali, la guerra fredda ed i maggiori conflitti che seguono il secondo dopoguerra (Corea, Vietnam, Afghanistan, Golfo Persico). All’inizio del XIX Secolo con l’impresa dei Fratelli Wright prende il via la conquista della terza dimensione. L’aeroplano, che inizialmente nella migliore delle ipotesi poteva apparire come un mezzo in grado di offrire al potere terrestre ed al potere navale solo una piccola capacità militare aggiuntiva, si sviluppa in una progressione esponenziale che non conosce precedenti nella storia dell’evoluzione della scienza e della tecnica, dove dottrina e tecnologia si rincorrono e si stimolano vicendevolmente. Con i progressi del mezzo aereo si sviluppa la dottrina che vede in Giulio Douhet il principale precursore ed ispiratore, tanto che molte delle sue intuizione restano tuttora valide. L’affermazione del potere aereo ad un livello che lo pone a pari dignità rispetto a quello delle due forze di superficie non riesce, tuttavia, a modificare o a far evolvere le teorie geopolitiche classiche. Questo non solo per una sorta di “miopia” dei più autorevoli interpreti, ma anche per questioni di approccio metodologico: il potere aereo non ha alle sue spalle una “storia” a cui attingere e fondamentalmente la geografia classica del tempo guarda solo alla dimensione piana. Lo sviluppo del potere aereo e della dottrina aerea dall’origine ai nostri giorni viene osservato attraverso sei periodi storici che caratterizzano le fasi della sua evoluzione: il periodo pionieristico dal 1880 al 1910 dove dapprima gli aerostati e poi l’aeroplano gettano le basi verso la conquista della terza dimensione; il periodo dal 1911 al 1935 che caratterizza l’esordio bellico dell’aeroplano; la fase dal ‘36 al ‘45 quando attraverso il secondo conflitto mondiale l’impiego bellico del mezzo aereo si espande, si consolida e si afferma sulla scena internazionale; il dopoguerra che contraddistingue l’intero arco della guerra fredda con le guerre per il dominio sul rimland e sull’heartland; la fase di transizione dal 1990 al 2003 che dopo la caduta del Muro di Berlino segna la trasformazione degli scenari e delle dottrine militari; e, l’ultimo periodo, dal 2003 ad oggi, sintesi di tutto quanto avvenuto in passato. Per ognuno di questi intervalli vengono evidenziati i momenti salienti che determinano l’affermazione del mezzo aereo dapprima quale supporto alle forze di superficie e poi, con la Seconda Guerra Mondiale ed il bombardamento di Hiroshima e Nagasaki come forza in grado di esprimersi in maniera autonoma sul piano strategico e persino di risolvere le sorti di un conflitto, come molti anni prima aveva predetto Douhet. Nonostante la forza delle teorie geopolitiche classiche, nei maggiori conflitti bellici del Novecento vengono premiate le potenze che meglio avevano compreso le capacità strategiche del mezzo aereo. All’evoluzione del potere aereo, racchiusa in un arco temporale relativamente breve (un secolo di storia), quando messa a confronto con quella del potere navale e terrestre, segue un’analisi delle linee di tendenza che caratterizzano la trasformazione degli scenari geopolitici. È in questi scenari che la dottrina aerea, insieme a quella terrestre e navale, deve oggi ed in futuro misurarsi. Sono gli scenari dei passato (conflitti ad alta intensità) a cui si aggiungono quelli delle operazione di pacificazione, in un contesto generale dove i riferimenti su cui poggiava il sistema westfalico dell’equilibrio delle forze sono in parte saltati. Le teorie geopolitiche classiche del XX Secolo, ispirate dalla contrapposizione tra potenze di mare e potenze di terra, sono venute meno per una serie di ragioni; tra queste ha certamente avuto un ruolo dominante l’evoluzione del potere aereo: il mezzo aereo ha di fatto annullato la dimensione geografica che un tempo rappresentava la base della competizione tra il treno e la nave per il dominio sul pianeta. Collegando l’evoluzione della dottrina aerea a quella degli scenari, è possibile giungere ad una comparazione tra potere terrestre, potere navale e potere aereo: il risultato stravolge le teorie geopolitiche classiche. Negli scenari ad alta intensità il potere aereo ha dimostrato di essere quasi sempre decisivo ed in taluni casi anche risolutivo. Il potere terrestre ed il potere navale non possono prescindere dal potere aereo, tanto che spesso comprendono organicamente segmenti di esso. Il potere aereo oltre a svolgere un ruolo di supporto essenziale per le forze di superficie, è anche in grado di operare in maniera indipendente. Si tratta quindi solo di capire in quali scenari e situazioni può effettivamente giocare questo ruolo e come deve essere utilizzato negli altri scenari.XX Cicl

Functional Role of the Third Cytoplasmic Loop in Muscarinic Receptor Dimerization

By means of the expression of two chimeric receptors, alpha2/m3 and m3/alpha2, in which the carboxyl-terminal receptor portions, containing transmembrane (TM) domains VI and VII, were exchanged between the alpha2C adrenergic and the m3 muscarinic receptor, Maggio et al. (Maggio, R., Vogel, Z., and Wess, J. (1993) Proc. Natl. Acad. Sci. U. S. A. 90, 3103-31073) demonstrated that G protein-linked receptors are able to interact functionally with each other at the molecular level to form (hetero)dimers. In the present study we tested the hypothesis that interaction between receptors might depend on the presence of a long third intracellular (i3) loop and that shortening this loop could impair the capability of receptors to form dimers. To address this question, we initially created short chimeric alpha2 adrenergic/m3 muscarinic receptors in which 196 amino acids were deleted from the i3 loop (alpha2/m3-short and m3/alpha2-short). Although co-transfection of alpha2/m3 and m3/alpha2 resulted in the appearance of specific binding, the co-expression of the two short constructs (alpha2/m3-short and m3/alpha2-short), either together or in combination, respectively, with m3/alpha2 and alpha2/m3 did not result in any detectable binding activity. In another set of experiments, a mutant m3 receptor, m3/m2(16aa), containing 16 amino acids of the m2 receptor sequence at the amino terminus of the third cytoplasmic loop, which was capable of binding muscarinic ligands but was virtually unable to stimulate phosphatidylinositol hydrolysis, was also mutated in the i3 loop, resulting in the m3/m2(16aa)-short receptor. Although co-transfection of m3/m2(16aa) with a truncated form of the m3 receptor (m3-trunc, containing an in frame stop codon after amino acid codon 272 of the rat m3 sequence) resulted in a considerable carbachol-stimulated phosphatidylinositol breakdown, the co-transfection of m3/m2(16aa)-short with the truncated form of the m3 receptor did not result in any recovery of the functional activity. Thus, these data suggest that intermolecular interaction between muscarinic receptors, involving the exchange of amino-terminal (containing TM domains I-V) and carboxyl-terminal (containing TM domains VI and VII) receptor fragments depends on the presence of a long i3 loop. One may speculate that when alternative forms of receptors with a different length of the i3 loop exist, they could have a different propensity to dimerize

The Paired Activation of the Two Components of the Muscarinic M3 Receptor Dimer Is Required for Induction of ERK1/2 Phosphorylation *

Muscarinic M(3) receptors stimulate ERK1/2, the mitogen-activated protein kinase pathway. A mutant of the muscarinic M(3) receptor in which most of the third intracellular (i3) loop had been deleted (M(3)-short) completely lost the ability to stimulate the ERK1/2 phosphorylation in COS-7 cells. This loss was evident despite the fact that the receptor was able to couple efficiently to the phospholipase C second messenger pathway. In co-transfected cells, M(3)-short greatly reduced the ability of M(3) to activate ERK1/2. In another set of experiments we tested the ability of a mutant M(3)/M(2)(16aa) receptor, in which the first 16 amino acids of the i3 loop of the M(3) receptor were replaced with the corresponding segment of the muscarinic M(2) receptor to stimulate ERK1/2 phosphorylation. This mutant is not coupled to Galpha(q), but it is weakly coupled to Galpha(i). Despite its coupling modification this receptor was able to stimulate ERK1/2 phosphorylation. Again, M(3)-short greatly reduced the ability of M(3)/M(2)(16aa) to activate ERK1/2 in co-transfected cells. Similar results were obtained in stable-transfected Chinese hamster ovary (CHO) cells lines. In CHO M(3) cells carbachol induced a biphasic increase of ERK1/2 phosphorylation; a first increase at doses as low as 0.1 microm and a second increase starting from 10 microm. In CHO M(3)-short and in double-transfected CHO M(3)/M(3)-short cells we observed only the lower doses increase of ERK1/2 phosphorylation; no further increase was observed up to 1 mm carbachol. This suggests that in double-transfected CHO cells M(3)-short prevents the effect of the higher doses of carbachol on the M(3) receptor. In a final experiment we tested the ability of co-transfected chimeric alpha(2)/M(3) and M(3)/alpha(2) receptors to activate the ERK1/2 pathway. When given alone, carbachol and, to a lesser extent, clonidine, stimulated the coupling of the co-transfected chimeric receptors to the phospholipase C second messenger pathway, but they were unable to stimulate ERK1/2 phosphorylation. On the contrary, a strong stimulation of ERK1/2 phosphorylation was observed when the two agonists were given together despite the fact that the overall increase in phosphatidylinositol hydrolysis was not dissimilar from that observed in cells treated with carbachol alone. Our data suggest that the activation of the ERK1/2 pathway requires the coincident activation of the two components of a receptor dimer

A new data-driven framework to select the optimal replenishment strategy in complex supply chains

- Part of special issue: 10th IFAC Conference on Manufacturing Modelling, Management and Control MIM 2022: Nantes, France, 22-24 June 2022. Edited by Alain Bernard, Alexandre Dolgui, Hichem Haddou Benderbal, Dmitry Ivanov, David Lemoine, Fabio Sgarbossa - Copyright © 2022 The Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)Motivated by the high variability of markets occurred in the last years, which in turns determined significant uncertainty in lead times and supply chain dynamics, this paper introduces a data-driven framework based on machine learning and metaheuristic optimization to dynamically select the most suitable replenishment strategy for a complex two-echelon (supplier-inventory-factory) supply chain (SC) problem with perishable product and stochastic lead times. Since the supplier dispatches the product (i.e., the raw material) with a fixed expiration date, the product shelf-life strictly depends on the related delivery lead time, which is subject to uncertainty. In addition, a minimum order quantity has to be fulfilled and the time between two consecutive orders cannot be less than one month. The aim of the work is to select the most suitable replenishment strategy able to minimize the average stock level, which is a surrogate cost metric, while respecting a target fill rate. Considering a smoothing order-up-to policy, the data-driven prediction-optimization framework makes use of Artificial Neural Network (ANN) and Particle Swarm Optimization (PSO) to select the best replenishment parameters (i.e., forecasting factor, proportional controller and safety stock factor) able to dynamically enhance the SC economic performance under the fill rate constraint. The ability of the framework under the predictive and the optimization perspective is assessed and a sensitivity analysis on the influence of replenishment parameters is presented as well

The properties and the formation mechanism of the stellar counter-rotating components in NGC 4191

We disentangle two counter-rotating stellar components in NGC 4191 and characterize their physical properties (kinematics, morphology, age, metallicity, and abundance ratio). We performed a spectroscopic decomposition on integral field data to separate the contribution of two stellar components to the observed galaxy spectrum across the field of view. We also performed a photometric decomposition, modelling the galaxy with a S\'ersic bulge and two exponential disks of different scale length, with the aim of associating these structural components with the kinematic components. We measured the equivalent width of the absorption line indices on the best fit that represent the kinematic components and compared our measurements to the predictions of stellar population models. We have evidence that the line-of-sight velocity distributions (LOSVDs) are consistent with the presence of two distinct kinematic components. The combined information of the intensity of the LOSVDs and photometry allows us to associate the S\'ersic bulge and the outer disk with the main kinematic component, and the inner disk with the secondary kinematic component. The two kinematic stellar components counter-rotate with respect to each other. The main component is the most luminous and massive, and it rotates slower than the secondary component, which rotates along the same direction as the ionized gas. We also found that the two kinematic components have the same solar metallicity and sub-solar abundance ratio, without the presence of significant radial gradients. On the other hand, their ages show strong negative gradients and the possible indication that the secondary component is the youngest. We interpret our results in light of recent cosmological simulations and suggest gas accretion along two filaments as the formation mechanism of the stellar counter-rotating components in NGC 4191 (Abridged).Comment: 10 pages, 10 figure. Accepted for publication in Astronomy and Astrophysic

Beam dynamics studies and emittance optimization in the CTF3 linac at CERN

Small transverse beam emittances and well-known lattice functions are crucial for the 30 GHz power production in the Power Extraction and Transfer Structure (PETS) and for the commissioning of the Delay Loop of the CLIC Test Facility 3 (CTF3). Following beam dynamics simulation results, two additional solenoids were installed in the CTF3 injector in order to improve the emittance. During the runs in 2005 and 2006, an intensive measurement campaign to determine Twiss parameters and beam sizes was launched. The results obtained by means of quadrupole scans for different modes of operation suggest emittances well below the nominal .n,rms = 100 ?Î?Êm and a good agreement with PARMELA simulations

Efficient long-pulse fully-loaded CTF3 linac operation

An efficient RF to beam energy transfer in the accelerating structures of the drive beam is one of the key points of the Compact Linear Collider (CLIC) RF power source. For this, the structures are fully beam-loaded, i.e. the accelerating gradient is nearly zero at the downstream end of each structure. In this way, about 96 % of the RF energy can be transferred to the beam. To demonstrate this mode of operation, 1.5 ..s long beam pulses are accelerated in six fully loaded structures in the CLIC Test Facility (CTF3) Linac. The final beam energy is compared to the input RF power of the structures, proving the efficient energy transfer