UN MODELLO DI STIMA DEL TRAFFICO TRAMITE LA RIPARTIZIONE TRA AEROPORTI DI UNA REGIONE (TRAFFIC ALLOCATION MODEL)

2004/2005XVIII Ciclo1978Versione digitalizzata della tesi di dottorato cartacea

From Differential Geometry of Curves to Helical Kinematics of Continuum Robots Using Exponential Mapping

Kinematic modeling of continuum robots is challenging due to the large deflections that these systems usually undergone. In this paper, we derive the kinematics of a continuum robot from the evolution of a three-dimensional curve in space. We obtain the spatial configuration of a continuum robot in terms of exponential coordinates based on Lie group theory. This kinematic framework turns out to handle robotic helical shapes, i.e. spatial configurations with constant curvature and torsion of the arm

Non-Prehensile Object Transportation via Model Predictive Non-Sliding Manipulation Control

This article proposes a model predictive non-sliding manipulation (MPNSM) control approach to safely transport an object on a tray-like end-effector of a robotic manipulator. For the considered non-prehensile transportation task to succeed, both non-sliding manipulation and the robotic system constraints must always be satisfied. To tackle this problem, we devise a model predictive controller enforcing sticking contacts, i.e., preventing sliding between the object and the tray, and assuring that physical limits such as extreme joint positions, velocities, and input torques are never exceeded. The combined dynamic model of the physical system, comprising the manipulator and the object in contact, is derived in a compact form. The associated non-sliding manipulation constraint is formulated such that the parametrized contact forces belong to a conservatively approximated friction cone space. This constraint is enforced by the proposed MPNSM controller, formulated as an optimal control problem that optimizes the objective of tracking the desired trajectory while always satisfying both manipulation and robotic system constraints. We validate our approach by showing extensive dynamic simulations using a torque-controlled 7-degree-of-freedom (DoF) KUKA LBR IIWA robotic manipulator. Finally, demonstrative results from real experiments conducted on a 21-DoF humanoid robotic platform are shown

Aging changes complexity of heart rate dynamics assessed by entropy and Lyapunov exponent analysis

In recent years, many research groups are trying to quantify the physiological signals of an individual, proposing new models to assess the complex dynamics of biological control systems. Indeed, life coincides with the good handling of the structures in the organism and of physiological control mechanisms, while disease and death coincide with the loss of structure and of coordinated functions. The homeodynamic systems which normally govern health are the same that cause pathological events when activated inadequately, or rather, when the balance between order and chaos of the elementary physiological processes is no longer effectively controlled in relation to any type of stress, both external and internal to the body. In a complex system, loss or alteration of communication between physiological signals means pathology. In this paper a signal analysis method based on Entropy (E), Lyapunov exponent (1), Median Absolute Deviation (MAD), Multiscale Entropy (MSE), is proposed to estimate the complexity of long-range temporal correlation heart rate (HR) time series for an elderly person and a young person both healthy. These new methods could improve overall understanding of the physiological system of the human organism, by adopting new models and experimental paradigms, such as those of fractality and entropy, who have the ability to direct from an organ medicine to a modern systemic medicine

Mycotoxin production in liquid culture and on plants infected with Alternaria spp. isolated from rocket and cabbage.

Fungi belonging to the genus Alternaria are common pathogens of fruit and vegetables with some species able to produce secondary metabolites dangerous to human health. Twenty-eight Alternaria isolates from rocket and cabbage were investigated for their mycotoxin production. Five different Alternaria toxins were extracted from synthetic liquid media and from plant material (cabbage, cultivated rocket, cauliflower). A modified Czapek-Dox medium was used for the in vitro assay. Under these conditions, more than 80% of the isolates showed the ability to produce at least one mycotoxin, generally with higher levels for tenuazonic acid. However, the same isolates analyzed in vivo seemed to lose their ability to produce tenuazonic acid. For the other mycotoxins; alternariol, alternariol monomethyl ether, altenuene and tentoxin a good correlation between in vitro and in vivo production was observed. In vitro assay is a useful tool to predict the possible mycotoxin contamination under field and greenhouse conditions

Static hot air and infrared rays roasting are efficient methods for aflatoxin decontamination on hazelnuts

Aflatoxins are a group of secondary metabolites produced by members of Aspergillus Section Flavi that are dangerous to humans and animals. Nuts can be potentially contaminated with aflatoxins, often over the legal threshold. Food processes, including roasting, may have different effects on mycotoxins, and high temperatures have proven to be very effective in the reduction of mycotoxins. In this work, two different roasting methods—traditional static hot air roasting and infra-red rays roasting—were applied and compared for the detoxification of hazelnuts from Italy and Turkey. At the temperature of 140 °C for 40 min of exposure, detoxification was effective for both roasting techniques. Residual aflatoxins after infra-red rays treatments were lower compared to static hot air roasting. On Italian hazelnuts, residual aflatoxins were lower than 5%, while for Turkish hazelnuts they were lower than 15% after 40 min of exposure to an infra-red rays roaster. After roasting, the perisperm was detached from the nuts and analyzed for aflatoxin contents. Residual aflatoxins in the perisperm ranged from 80% up to 100%. After roasting, the lipid profile and the nutritional quality of hazelnuts were not affected. Fatty acid methyl esters analyses showed a similar composition for Italian and Turkish hazelnuts

Nonlinear Model Predictive Control for the Stabilization of a Wheeled Unmanned Aerial Vehicle on a Pipe

This letter addresses the task of stabilizing a wheeled unmanned aerial vehicle on a pipe, which is an emerging applica- tion in oil and gas facilities for nondestructive measurements. After the derivation of the dynamic model of the system, a discrete-time nonlinear model predictive controller is designed over a finite horizon. The analysis of the asymptotic stability of the designed controller is carried out. Numerical tests show the performance and the robustness of the proposed solution

Transvaginal ultrasound evaluation of the pelvis and symptoms after laparoscopic partial cystectomy for bladder endometriosis

Objective: To evaluate transvaginal sonography (TVS) findings after laparoscopic partial cystectomy for bladder endometriosis and to correlate postsurgical ultrasound findings with symptoms. Material and Methods: A retrospective study including women who underwent laparoscopic partial cystectomy for bladder endometriosis. Within 12 months after surgery, TVS examination was conducted in all patients to evaluate the bladder morphology, and the presence of any postsurgical sonographic findings of the pelvis. Painful symptoms were assessed using a visual analogue scale. Results: A total of 40 women were included. At the follow-up visit, 25 patients were receiving medical treatment while 15 had declined post-surgical therapy and had tried to conceive. The presence of bladder deep-infiltrating endometriosis (DIE) was found in nine (22.5%), fibrotic thickening of the bladder wall was found in 15 (37.5%), and normal bladder morphology was observed in 16 (40%). There was a correlation between anterior adenomyosis and bladder DIE, and fibrotic thickening of the bladder. Patients with TVS signs of bladder DIE and anterior adenomyosis suffered more dysmenorrhea and dysuria than patients with normal bladder. Conclusion: Post-operative TVS can detect the alteration of pelvis and could explain the causes of the persistence of symptoms. (J Turk Ger Gynecol Assoc 2022; 23: 145-53

New endoscopic capsule vs upper gastrointestinal endoscopy in preoperative work-up of obese candidate for bariatric surgery: Relevance of a pilot study in the COVID-19 era

: Background and study aims  Obesity represents a major health concern; bariatric surgery is the most effective treatment reducing and maintaining weight loss. The role of a routine esophagogastroduodenoscopy (EGD) prior bariatric surgery is still debated. Moreover, in this scenario of COVID-19 pandemic, EGD is even more questionable due to the procedural risk of viral transmission. A new model of video-endoscopic capsule (VEC) recently has been introduced as a good alternative to the EGD. The aim of this study was to determine if this new capsule is an adequate diagnostic alternative to EGD in the work-up of patients selected for bariatric surgery, particularly in the setting of COVID-19. Patients and methods  From January to November 2020, 27 patients selected for bariatric surgery were enrolled in this pilot study to assess for noninferiority of VEC compared to EGD in detection of upper gastrointestinal disease. Results  VEC had sensitivity, specificity, and positive and negative predictive values in identification of significant lesions of 91.3 %, 83.33 %, 98.01 %, and 51.57 %, respectively, compared with EGD as the standard criterion. The accuracy was 90.51 % (95 % CI, 73.75 %-98.18 %) and the chi-square statistic is 0.1153 ( P  = 0.73). Conclusions  Our report confirms the diagnostic noninferiority of VEC in preoperative work-up of patients selected for bariatric surgery, compared to EGD. This is very important, particularly during the COVID-19 pandemic, given the high risk of contamination with EGD. Larger multicenter studies are required to confirm our preliminary results