OPTIMIZATION OF PRODUCTION LINES USING ADVANCED CNC INTERPOLATION METHODS AND DISTRIBUTION OF CONTROL LOGIC

These days, information technology really makes the difference in manufacturing industry. High performance computers allow to realize control algorithms of increasing complexity and high speed reliable computer networks allows the communication between different devices and realization of advanced distributed control applications. In this thesis, we focus on the optimization of the production lines using two different approaches. First we focus on the improvement of a single workstation of the production line, then we focus on the improvement of the interactions between various stations of the production line.. A typical workstation that can be found in a production line is the machine tool for manufacturing workpieces. Advances in manufacturing technologies allow to increase quality and efficiency in production lines, but also ask for new and increasing requirements on the motion planning and control systems. The increase of CPU processing power has permitted, in traditional CNC systems, the introduction of NURBS interpolation capabilities, thus determining a further increase in machining quality and efficiency. This has posed new and still unsolved issues, such as the need to satisfy multiple opposite constraints like limiting chord error, acceleration and jerk and offering real-time guarantees. In addition, the ability of privileging the production throughput by relaxing one or more of the previous constraints in a simple way has emerged as another requirement of modern manufacturing plants. Nevertheless, none of the existing NURBS interpolators have these characteristics. In this thesis, we propose a NURBS interpolator that is able to satisfy all the manufacturing technology requirements and is able to respect, thanks to its bounded computational complexity, the position control real-time constraints. Such interpolator is easily reconfigurable, i.e. it can relax some of the constraints and can be adapted in order to include constraints that were not originally considered. Performances of the proposed algorithm have been evaluated both by simulations and by real milling experiments. However, improvements in productivity of a the machine tool can be neutralized if the various workstations of the production line are not properly synchronized. Distributed control allows to improve the coordination of different workstations but its design is challenging. The IEC 61499 standard has been developed to ease the modeling and design of distributed control systems, providing advanced concepts of software engineering (such as abstraction, encapsulation, reuse) to the world of control engineering. The introduction of such standard in already existing control environments poses challenges, since the widespread IEC 61131-3 programming standard is not compatible with the new standard. In order to solve this problem, this thesis presents an architecture that permits to integrate modules of the two standards, allowing to exploit the benefits of both. The proposed architecture is based on coexistence of control logic of both standards. Each standard interacts with some particular interfaces that encapsulate information and functionalities to be exchanged with the other standard. A methodology of integration of 61131-3 modules in a 61499 distributed solution based on such architecture is also developed, and it is described via a case study to prove feasibility and benefits

Integration of existing IEC 61131-3 systems in an IEC 61499 distributed solution

The IEC 61499 standard allows to model and design new generation control systems, providing innovative concepts of software engineering (such as abstraction, encapsulation, reuse) to the world of control engineering. The industrial reception of the standard, however, is still in an early stage, also because its introduction results in the adoption of a programming paradigm profoundly different than the widespread IEC 61131-3. This paper presents a method for the integration of the two standards, that allows to exploit the benefits of both. The proposed architecture is based on the parallel execution of both environments that interact with each other through some specific interfaces. A test implementation of the architecture is also presented to demonstrate the feasibility of the proposed solution

Can new organic cropping systems produce vegetables with lower use of resources and losses of nitrate?

To secure a sustainable production of plant foods for the future, there is a need to develop new cropping systems. These systems should have reduced needs of external resources and reduced environmental impact, while product yields are maintained at high level. Therefore, field trials were performed in Italy, Slovenia, Germany and Denmark with the aim to study new organic cropping systems for production of vegetable crops; and the systems’ effect on labor and energy consumption and the risk of losing nitrate to the water environment. The cropping systems included an in-season living mulch to exploit ecosystem services by attracting beneficial insects, suppressing weeds, and taking up excess nitrogen during production of two high-value crops of leek and cauliflower. The first year results show that high yields and quality were maintained if the living mulches were properly managed e.g. by sowing date or root pruning to control plant competition. The systems including living mulches changed the costs from +22 to -2% and total energy consumption from +14 to -4% compared to sole cropping depending on the change of management techniques in each country. The proportion between human power and fossil fuel consumption was changed. The risk of nitrate leaching was affected to a minor degree depending on the spatial layout of living mulch and crop rows. The study indicates that new cropping systems can be developed based on in-season living mulches for organic production with high yields, weed suppression and reduction of the risk of nitrate leaching. However, the management of the living mulches in terms of machinery, agronomic techniques and timing needs to be developed to optimize outcomes for food security, energy use and environmental impact. The study is part of the INTERVEG project

EFFECT OF LIVING MULCH ON PEST/BENEFICIAL INTERACTION

The aim of this study was to evaluate the effect of cover crops on pest/beneficial dynamics and to test the potential of living mulch on enhancing biological control against insect pests. The research, carried out in the frame of the InterVeg (Core Organic II) project, involved four European countries: Germany, Slovenia, Denmark and Italy. Three crops were tested: cauliflower, leek and artichoke. The preliminary results obtained in Italy on cauliflower, indicated that the living mulch did not affect the infestation of the cabbage butterfly, Pieris brassicae, showing no detrimental effect of this technique on pest dynamics. A very high level of parasitization against cabbage butterfly was detected either in the living mulch crop (88%) and in the sole one (63%). Living mulch showed to increase the spider and rove beetle activity density, while the carabid activity density was slightly higher in the sole crop

EFFECT OF LIVING MULCH ON PEST/BENEFICIAL INTERACTION

The aim of this study was to evaluate the effect of cover crops on pest/beneficial dynamics and to test the potential of living mulch on enhancing biological control against insect pests. The research, carried out in the frame of the InterVeg (Core Organic II) project, involved four European countries: Germany, Slovenia, Denmark and Italy. Three crops were tested: cauliflower, leek and artichoke. The preliminary results obtained in Italy on cauliflower, indicated that the living mulch did not affect the infestation of the cabbage butterfly, Pieris brassicae, showing no detrimental effect of this technique on pest dynamics. A very high level of parasitization against cabbage butterfly was detected either in the living mulch crop (88%) and in the sole one (63%). Living mulch showed to increase the spider and rove beetle activity density, while the carabid activity density was slightly higher in the sole crop

Search for Third Generation Vector Leptoquarks in p anti-p Collisions at sqrt(s) = 1.96 TeV

We describe a search for a third generation vector leptoquark (VLQ3) that decays to a b quark and tau lepton using the CDF II detector and 322 pb^(-1) of integrated luminosity from the Fermilab Tevatron. Vector leptoquarks have been proposed in many extensions of the standard model (SM). Observing a number of events in agreement with SM expectations, assuming Yang-Mills (minimal) couplings, we obtain the most stringent upper limit on the VLQ3 pair production cross section of 344 fb (493 fb) and lower limit on the VLQ3 mass of 317 GeV/c^2 (251 GeV/c^2) at 95% C.L.Comment: 7 pages, 2 figures, submitted to PR

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson