Optimal Trajectories for Near-Earth-Objects Using Solar Electric Propulsion (SEP) and Gravity Assisted Maneuver

The future interplanetary missions will probably use the conventional chemical rockets to leave the sphere of influence of the Earth, and solar electric propulsion (SEP) to accomplish the other maneuvers of the mission. In this work the optimization of interplanetary missions using solar electric propulsion and Gravity Assisted Maneuver to reduce the costs of the mission, is considered. The high specific impulse of electric propulsion makes a Gravity Assisted Maneuver 1 year after departure convenient. Missions for several Near Earth Asteroids will be considered. The analysis suggests criteria for the definition of initial solutions demanded for the process of optimization of trajectories. Trajectories for the asteroid 2002TC70 are analyzed. Direct trajectories, trajectories with 1 gravity assisted from the Earth and with 2 gravity assisted from the Earth and either Mars are present. An indirect optimization method will be used in the simulations

A task-priority based control approach to distributed data-driven ocean sampling

The paper illustrates the basic ideas and relevant algorithmic developments underlying the proposal for a task-priority based control approach to distributed data-driven ocean sampling applications. This approach is deemed allowing a better formalization of the overall motion problem of the involved team of agents; that apart the ultimate mission objective, also result characterized by other different control objectives directly related with both operability and safety aspects of the entire sampling system. Also, the proposed approach, other than leading to a unifying algorithmic structure, also seems allowing to foresee good possibilities for different types of downgrading toward efficient decentralized implementations

Indirect Optimization of Satellite Deployment into a Highly Elliptic Orbit

The analysis of the optimal strategies for the deployment of a spacecraft into a highly elliptic orbit is carried out by means of an indirect optimization procedure, which is based on the theory of optimal control. The orbit peculiarities require that several perturbations are taken into account: an 8x8 model of the Earth's potential is adopted and gravitational perturbations from Moon and Sun together with solar radiation pressure are considered. A procedure to guarantee convergence and define the optimal switching structure is outlined. Results concerning mission with up to 4.5 revolutions around the Earth are given and significant features of this kind of deployment are highlighte

Distributed Task-priority Based Control in Area Coverage & Adaptive Sampling

Abstract\u2014The paper presents the first simulative results and algorithmic developments of the task-priority based control applied to a distributed sampling network in an area coverage or adaptive sampling mission scenario. The proposed approach allowing the fulfilment of a chain of tasks with decreasing priority each of which directly related to both operability and safety aspects of the entire mission. The task-priority control is presented both in the centralized and decentralized implementations showing a comparison of performance. Finally simulations of the area coverage mission scenario are provided showing the effectiveness of the proposed approac

Electric Drive Supervisor for Milling Process 4.0 Automation : A Process Analytical Approach with IIoT NIR Devices for Common Wheat

The milling industry envisions solutions to become fully compatible with the industry 4.0 technology where sensors interconnect devices, machines and processes. In this contest, the work presents an integrated solution merging a deeper understanding and control of the process due to real-time data collection by MicroNIR sensors (VIAVI, Santa Rosa, CA)\u2014directly from the manufacturing process\u2014and data analysis by Chemometrics. To the aim the sensors were positioned at wheat cleaning and at the flour blends phase and near infrared spectra (951\u20131608 nm) were collected online. Regression models were developed merging the spectra information with the results obtained by reference analyses, i.e., chemical composition and rheological properties of dough by Farinograph\uae (Brabender GmbH and Co., Duisburg, Germany), Alveograph\uae (Chopin, NG Villeneuve-la-Garenne Cedex, France) and Extensograph\uae.(Brabender GmbH and Co., Duisburg, Germany) The model performance was tested by an external dataset obtaining, for most of the parameters, RPRED higher than 0.80 and Root Mean Squares Errors in prediction lower than two-fold the value of the reference method errors. The real-time implementation resulted in optimal (100% of samples) or really good (99.9%\u201380% of samples) prediction ability. The proposed work succeeded in the implementation of a process analytical approach with Industrial Internet of Things near infrared (IIoT NIR) devices for the prediction of relevant grain and flour characteristics of common wheat at the industrial level

Characterization of the cellular damage induced by Aflatoxin B1 in sea bream (Sparus aurata Linnaeus, 1758) hepatocytes

Gilthead sea bream (Sparus aurata L.) is one of the most intensively farmed fish spe- cies in the Mediterranean, greatly studied for the relevant economic value, although its sensitivity to Aflatoxin B1 (AFB1) has to be investigated, yet. The aim of this study was to perform an in vitro evalua- tion of cytotoxic potential of AFB1 on S. aurata hepatocytes in order to grade the range of AFB1 toxicity, and the boundary between acute and long-term toxicity. Primary monolayer cultures of hepatocytes from S. aurata juveniles were treated with a wide range of concentrations from 5x103 ng/ml to 2x10 2x10-5 ng/ml of AFB1 for a different period of exposure (24, 48, 72 hours). The cytotoxic activity was characterized by MTT reduction assay. After each exposition hepatocytes were examined for morphologic alterations and apoptosis induction. AFB1 exposure significantly reduced cell viability in a dose- and time-depend- ent manner. Dose-response curves obtained after 24, 48 and 72 hrs revealed that prolonged exposure times lead to a significant increase of the toxicpotencyofAFB toxic potency of AFB AFB1. Ourresultsdemonstratethat Our results demonstrate that S. aurata hepatocytes are highly sensitive to AFB1 exposure. Such scientific findings could provide new insights to investigate the real impact of aflatoxin on marine farmed fish

Minimal inhibitory and Mutant prevention concentrations of enrofloxacin for Pasteurella multocida from rabbits affected by pasteurellosis

Pasteurella multocida is the agent of one of the most significant diseases in rabbits and it is associated with a heterogeneous clinical picture. Drugs belonging to the fluoroquinolones class are useful to control pasteurellosis. Among them, enrofloxacin is one of the most used molecules in rabbit industry and it is the only one fluoroquinolone registered for this species in Italy. Enrofloxacin adopted dosages are currently based on Minimum Inhibitory Concentration (MIC). Nevertheless, MIC is not effective against possible pathogen sub-populations with lower susceptibility that may be selectively amplified, leading to possible problems of antibiotic resistance. Mutant Prevention Concentration (MPC) could represent an approach to minimize the risk of resistance selection in pathogens. The aim of this work was to test the sensitivity to enrofloxacin of P. multocida strains isolated from rabbits affected by pasteurellosis to evaluate if MPC-based dosages can represent a valid option. The study was performed on ten strains of P. multocida isolated from rabbits from two industrial farms of Puglia, South Italy. The sensitivity to enrofloxacin has been evaluated by MIC tests by microdilution method and MPC tests performed according to Marcusson et al. (2005) with minor modifications. The results of MIC and MPC tests have revealed that MPC dosages are on average 8,4 times higher than MIC dosages. This data highlight that, although MPC-based dosages are useful to prevent the selection of potential mutant, they could be higher than MIC-based ones, leading to possible issues related to their application in field, for example the potential risk of possible toxicity for animals and residues in meat

On the Connection Between Flap Side-Edge Noise and Tip Vortex Dynamics

The goal of the present work is to investigate how the dynamics of the vortical flow about the flap side edge of an aircraft determine the acoustic radiation. A validated lattice- Boltzmann CFD solution of the unsteady flow about a detailed business jet configuration in approach conditions is used for the present analysis. Evidence of the connection between the noise generated by several segments of the inboard flap tip and the aerodynamic forces acting on the same segments is given, proving that the noise generation mechanism has a spatially coherent and acoustically compact character on the scale of the flap chord, and that the edge-scattering effects are of secondary importance. Subsequently, evidence of the connection between the kinematics of the tip vortex system and the aerodynamic force is provided. The kinematics of the dual vortex system are investigated via a core detection technique. Emphasis is placed on the mutual induction effects between the two main vortices rolling up from the pressure and suction sides of the flap edge. A simple heuristic formula that relates the far-field noise spectrum and the cross-spectrum of the unsteady vortical positions is developed