Experimenting sensors network for innovative optimal control of car suspensions

This paper presents an innovative electronically controlled suspension system installed on a real car and used as a test bench. The proposed setup relies on a sensor network that acquires a large real-time dataset collecting the car vibrations and the car trim and, through a new controller based on a recently proposed theory developed by the authors, makes use of adjustable semi-active magneto-rheological dampers. A BMW series 1 is equipped with such an integrated sensors-controller-actuators device and an extensive test campaign, in real driving conditions, is carried out to evaluate its performance. Thanks to its strategy, the new plant enhances, at once, both comfort and drivability of the car, as field experiments show. A benchmark analysis is performed, comparing the performance of the new control system with the ones of traditional semi-active suspensions, such as skyhook devices: the comparison shows very good results for the proposed solution

Safe and secure control of swarms of vehicles by small-world theory

The present paper investigates a new paradigm to control a swarm of moving individual vehicles, based on the introduction of a few random long-range communications in a queue dominated by short-range car-following dynamics. The theoretical approach adapts the small-world theory, originally proposed in social sciences, to the investigation of these networks. It is shown that the controlled system exhibits properties of higher synchronization and robustness with respect to communication failures. The considered application to a vehicle swarm shows how safety and security of the related traffic dynamics are strongly increased, diminishing the collision probability even in the presence of a hacker attack to some connectivity channels

Leukocyte Counts and Ratios Are Predictive of Stroke Outcome and Hemorrhagic Complications Independently of Infections.

Background: Ischemic stroke patients show alterations in peripheral leukocyte counts that may result from the sterile inflammation response as well as the occurrence of early infections. We here aimed to determine whether alterations of circulating leukocytes in acute ischemic stroke are associated with long-term functional outcome and hemorrhagic complications, independently of the occurrence of infections. Methods: Blood laboratory values of patients with acute ischemic stroke, presenting within 4.5 h from symptom onset, were collected. Leukocyte subsets were analyzed in relation to 3-month functional outcome, mortality, and parenchymal hemorrhagic transformation (PH). A multivariable logistic regression analysis, considering the occurrence of early post-stroke infections, was performed for each outcome measure. Results: Five-hundred-ten patients were included in the study. Independently of infections, good functional outcome was associated with a lower neutrophil to lymphocyte ratio (NL-R, OR 0.906 [95% CI 0.822-0.998]), a higher lymphocyte count (OR 1.547 [95% CI 1.051-2.277]), a higher eosinophil count (OR 1.027 [95% CI 1.007-1.048]), and a higher eosinophil to leukocyte ratio (EoLeu-R, OR 1.240 [95% CI 1.071-1.436]) at admission. Death within 3 months was associated with higher NL-R (OR 1.103 [95% CI 1.032-1.179]) as well as with lower eosinophil counts (OR 0.909 [95% CI 0.827-0.999]). Patients developing parenchymal hemorrhagic transformation had higher neutrophil counts (OR 1.420 [95% CI 1.197-1.684]) as well as a higher NL-R (OR 1.192 [95% IC 1.088-1.305]). Conclusion: Leukocyte subtype profiles in the acute phase of ischemic stroke represent a predictor of outcome independently of infections. Stroke-evoked sterile inflammation is a pathophysiological relevant mechanism that deserves further investigation

OPTYRE—Real time estimation of rolling resistance for intelligent tyres

The study of the rolling tyre is a problem framed in the general context of nonlinear elasticity. The dynamics of the related phenomena is still an open topic, even though few examples and models of tyres can be found in the technical literature. The interest in the dissipation effects associated with the rolling motion is justified by their importance in fuel-saving and in the context of an eco-friendly design. However, a general lack of knowledge characterizes the phenomenon, since not even direct experience on the rolling tyre can reveal the insights of the correlated different dissipation effects, as the friction between the rubber and the road, the contact kinematics and dynamics, the tyre hysteretic behaviour and the grip. A new technology, based on fibre Bragg grating strain sensors and conceived within the OPTYRE project, is illustrated for the specific investigation of the tyre dissipation related phenomena. The remarkable power of this wireless optical system stands in the chance of directly accessing the behaviour of the inner tyre in terms of stresses when a real-condition-rolling is experimentally observed. The ad hoc developed tyre model has allowed the identification of the instant grip conditions, of the area of the contact patch and allows the estimation of the instant dissipated power, which is the focus of this paper

Damping control of polodes, inertia and natural frequencies: Theory and application to automotive suspensions

This paper shows how tunable dampers can help control the instant centre of rotation of a 2D rigid body and its polode in planar motion, which in turn implies that the inertia tensor can also be controlled. For mechanisms equipped with some elasticity the results show that damping can also control their natural frequencies. The foundation of a general theory to control the polode is presented, exploring the chance of an optimal control formulation of the problem via a variational control principle, approached by the LQR (Linear Quadratic Regulator) method, after a suitable linearization. Application to automotive suspension linkages is presented that demonstrates the control of the instant roll centre and axis and consequently its instant roll vibration frequency to optimize the response, when excited by lateral inertia forces

Protein crystallization on nucleating surfaces inspired by biomineralization

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Synthetic Crysotile Nano-Crystals as a Reference Standard to Investigate Surface-Induce Serum Albumin Structural Modifications

Geoinspired synthetic chrysotile, which represents an ideal asbestos reference standard, has been utilized to investigate homomolecular exchange of bovine serum albumin (BSA), the major plasma protein, between the adsorbed and dissolved state at the interface between asbestos fibers and biological medium. FTIR spectroscopy has been used to quantify BSA structural modifications due to surface adhesion on chrysotile fibers as a function of the surface coating extent. Circular dichroism spectroscopy has been used to investigate the adsorption/desorption equilibrium through analysis of the BSA structural perturbations after protein desorption from chrysotile surface. Data results show clearly that in the solid state BSA modifications are driven by surface interaction with the substrate, following a bimodal adsorption evidenced by two different binding constants. On the other hand, BSA desorbed in solution is able to rearrange, in the lack of substrate, although keeping irreversible modifications with respect to the native species. The lack of regaining its native structure certainly affects albumin interaction with biological environment. The present investigation on the stoichiometric synthetic geoinspired chrysotile nanocrystals is the first approach toward a deeper attempt to use standard synthetic chrysotile reference samples in mimicking the behavior of asbestos fibers and allows to better understand their interaction with a biological environment

Remarks on the Messinian evaporites of Zakynthos Island (Ionian Sea, Eastern Mediterranean)

Detailed mapping of the Neogene deposits on Zakynthos Island shows that the Messinian primary evaporite basins, formed over Ionian basement, are delimited by the westernmost outcrop of the Triassic evaporitic diapirs, located west of the Kalamaki-Argasi Messinian gypsum unit. The post-Miocene external Ionian thrust is emplaced west of the Triassic diapirs. Planktonic foraminifera biostratigraphy indicates that primary evaporite accumulation took place probably during the first stage of the Messinian salinity crisis (5.96-5.60 Ma), in shallower parts of a foreland basin, formed over the Pre-Apulian and the Ionian zone basement. Establishment of these depositional environments, before the Ionian thrust emplacement, was probably due to the particularities of the foreland basin, which extended from the external Ionian to the internal Pre-Apulian zone. Field observations, borehole data and an onshore seismic profile show that the Neogene sediments over the Pre-Apulian basement correspond to the foredeep through forebulge domain of the foreland basin, as it is documented from their spatial thickness distribution. In contrast, the Neogene sediments over the Ionian basement correspond to the wedge top of the foreland basin, which was less subsiding, as it is deduced by their reduced thickness. This lower subsidence rate was the result of the concurrent diapiric movements of the Ionian Triassic evaporites. In Agios Sostis area, located over Pre-Apulian basement, the Neogene sequence is intercalated by decametre-thick resedimented blocks consisting of shallow water selenite. To the southeast, this mass-wasting Messinian gypsum passes to mainly gypsum turbidite. In Kalamaki-Argasi area, located over Ionian basement, the shallow water environment led to the deposition of the observed primary gypsum. Erosion of the primary gypsum of both forebulge and wedge top supplied the foreland basin’s depocenter with gypsum turbidites. Η λεπτομερής χαρτογράφηση των Νεογενών αποθέσεων της Ζακύνθου δείχνει ότι οι λεκάνες πρωτογενούς Μεσσήνιας εβαποριτικής απόθεσης, που σχηματίστηκαν πάνω σε Ιόνιο υπόβαθρο, οριοθετούνται από τη δυτικότερη εμφάνιση των Τριαδικών εβαποριτικών διάπειρων (δυτικά της Μεσσήνιας ενότητας γύψου Καλαμάκι-Αργάσι). Η μετα-Μειοκαινική εξωτερική Ιόνια επώθηση τοποθετείται δυτικά αυτών των Τριαδικών διάπειρων. Βιοστρωματογραφική ανάλυση των συναθροίσεων πλαγκτονικών τρηματοφόρων στα Νεογενή ιζήματα δείχνει ότι η συσσώρευση πρωτογενούς εβαπορίτη έλαβε χώρα πιθανά κατά το πρώτο στάδιο της κρίσης αλμυρότητας του Μεσσηνίου (5.96-5.60 Εκατ.χρ.), στα αβαθέστερα τμήματα της λεκάνης προχώρας, η οποία σχηματίστηκε πάνω στο Προ-Απούλιο και Ιόνιο αλπικό υπόβαθρο. Ο σχηματισμός των περιβαλλόντων ιζηματογένεσης, πριν από την Ιόνια επώθηση, πιθανά οφείλεται στις ιδιαιτερότητες της λεκάνης προχώρας, η οποία εκείνο το διάστημα εκτείνονταν από την εξωτερική Ιόνια ως την εσωτερική Προ-Απούλια ζώνη. Νέα δεδομένα υπαίθρου, σε συνδυασμό με τη βιοστρωματογραφία, τα στοιχεία γεωτρήσεων και μία διαθέσιμη σεισμική τομή δείχνουν ότι τα Νεογενή ιζήματα πάνω στο Προ-Απούλιο υπόβαθρο αντιστοιχούν στον τμήμα της λεκάνης προχώρας, από το προβύθισμα (foredeep) ως την πρόσθια ανύψωση (forebulge), όπως αυτό διαπιστώνεται από την χωρική κατανομή του πάχους τους. Αντίθετα, τα Νεογενή ιζήματα πάνω στο Ιόνιο υπόβαθρο αντιστοιχούν στο τμήμα της λεκάνης προχώρας που βρίσκεται πάνω στο μετωπικό πρίσμα της ορογένεσης (wedge top), το οποίο βυθίζονταν λιγότερο όπως συνάγεται από το ελαττωμένο πάχος των ιζημάτων. Ο μικρότερος ρυθμός βύθισης οφείλεται στις διαπειρικές κινήσεις των Τριαδικών εβαποριτών. Στη Νεογενή ακολουθία, που βρίσκεται πάνω σε Προ-Απούλιο υπόβαθρο (περιοχή Άγιος Σώστης), παρεμβάλλονται επανιζηματοποιημένα μπλοκ δεκαμετρικού πάχους αποτελούμενα από σεληνίτη μικρού βάθους απόθεσης. Προς νότο, αυτή η βαρυτικά μεταφερόμενη μάζα της Μεσσήνιας γύψου μεταπίπτει κυρίως σε τουρβιδιτική γύψο. Στην περιοχή Καλαμάκι-Αργάσι που βρίσκεται πάνω σε Ιόνιο υπόβαθρο, το αβαθές περιβάλλον οδήγησε στην απόθεση της παρατηρούμενης πρωτογενούς γύψου. Η διάβρωση της πρωτογενούς γύψου τόσο της πρόσθιας ανύψωσης όσο και του μετωπικού πρίσματος επώθησης τροφοδότησαν το προβύθισμα της λεκάνης προχώρας με τουρβιδίτες γύψου

Aneurysms of anomalous splenomesenteric trunk: clinical features and surgical management in two cases

Aneurysms of the splenic artery that anomalously arise from a splenomesenteric trunk are a rarity. Aneurysmal disease of visceral arteries is found in only 0.2% of the general population. The celiac trunk and superior mesenteric artery (SMA) are involved in less than 10% of all visceral aneurysms. Although rupture seems to occur in 20% to 22% of patients, the related mortality rate can rise as high as 100%. Anomalies of the celiac trunk and SMA, more common than previously claimed, include the splenic artery arising from the SMA, which occurs in only 1% of patients. We present two cases of young patients who had 4-cm aneurysms behind the pancreas that involved an anomalous splenic artery. The first patient required dissection of the entire splenopancreatic bloc through a transverse abdominal incision to excise the aneurysm and repair the SMA. The second patient was treated by the classic approach, through a median incision and by entering the mesenteric root. There do not seem to be reports of similar cases, except for two cases of aneurysms involving the celiomesenteric trunk. The cause of these aneurysms can be attributed to mesenchymal alterations during the embryonic formation of aortic collateral branches. A correct surgical approach to splanchnic aneurysms calls for awareness of potential vascular variations of the arteries and their collateral pathways