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Differential Geometry: Foundation of Cauchy-Riemann and Pseudohermitian Geometry (Book I-C)
No full textSearch for medium effects using jet axis decorrelation in inclusive jets from PbPb collisions at = 5.02 TeV
No full textThe jet axis decorrelation in inclusive jets is studied using lead-lead (PbPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The jet axis decorrelation is defined as the angular difference between two definitions of the jet axis. It is obtained by applying two recombination schemes on all the constituents of a given jet reconstructed by the anti-kT sequential algorithm with a distance parameter of R = 0.4. The data set, corresponding to an integrated luminosity of 0.66 nb−1, was collected in 2018 with the CMS detector at the CERN LHC. The jet axis decorrelations are examined across collision centrality selections and intervals of jet transverse momentum. A centrality dependent evolution of the measured distributions is observed, with a progressive narrowing seen in more central events. This narrowing could result from medium-induced modification of the internal jet structure or reflect color charge effects in energy loss. This new measurement probes jet substructure in previously unexplored kinematic domains and show great promise for providing new insights on the color charge dependence of energy loss to jet-quenching models
Search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV in the diphoton final state in proton-proton collisions at sqrt(s) = 13 TeV
No full textThe results of a search for a standard model-like Higgs boson decaying into two photons in the mass range between 70 and 110 GeV are presented. The analysis uses the data set collected by the CMS experiment in proton-proton collisions at s=13TeV corresponding to integrated luminosities of 36.3fb−1, 41.5fb−1 and 54.4fb−1 during the 2016, 2017, and 2018 LHC running periods, respectively. No significant excess over the background expectation is observed and 95% confidence level upper limits are set on the product of the cross section and branching fraction for decays of an additional Higgs boson into two photons. The maximum deviation with respect to the background is seen for a mass hypothesis of 95.4 GeV with a local (global) significance of 2.9 (1.3) standard deviations. The observed upper limit ranges from 15 to 73 fb
Surface roughness of thermally modified and unmodified selected wood species after sanding
Get PDFThe paper aims to determine by measuring whether the Thermo-Vacuum modification of selected types of wood causes an increase or decrease in surface roughness after its sanding using drum sander. The roughness change is explained more comprehensively with respect to the change in density and hardness. The surface roughness was measured with a Keyence VHX-7000 digital microscope. The measured data showed that the Thermo-Vacuum modification reduced the surface roughness of beech wood. On the other hand, pine, oak, and chestnut wood increased in roughness probably due to a decrease in their hardness. This caused deeper grooves to be cut in the sanding process. The paper thus answers the question of whether wood modification helps the woodworking processes to achieve lower surface roughness or, on the contrary, increases it, which will require further surface treatments
Photography, Image Agency, and Visual Ecocriticism: Henri Cartier-Bresson’s Lucania
No full textDuring the post-war years, within the reflection on the Southern question, Carlo Levi’s Christ Stopped at Eboli (1945) crystallized Lucania into a form of eternal damnation, permeated by misery and disease, as the symbolic negative pole of a rigidly divided Italy where the north was instead idealized as the healthy, strong, and productive part of the country. Against this backdrop, Cartier-Bresson’s photography reveals a more open and receptive perspective, free from ideological and symbolic constraints. The authenticity and intense vitality of the French photographer’s work still resonates today, making it capable of signifying and acting in contemporaneity. This essay takes its cue from the Cartier-Bresson collection held at the Rocco Scotellaro Documentation Center in Tricarico (Matera), which houses the photographs taken by the French photographer during his two reportages in Lucania, in 1951-1952 and in 1972-1973 respectively. Analyzing Cartier-Bresson’s work and those of other photographers who centered their works on Basilicata during those years (such as David Seymour, Arturo Zavattini, and Franco Pinna), the essay focuses on the question of image agency (Mitchell 2005; Bredekamp 2010) in relation to the environmental issue and visual ecocriticism
Feasibility and effectiveness of metaheuristic algorithms in optimizing valve placement for Water Distribution Networks optimization
Get PDFIn Italy, the majority of municipalities are small towns, with 70% of them having a population of less than 5,000 inhabitants. These small towns often face more complex challenges compared to larger cities, both due to limited economic resources and less developed infrastructure. This disparity is also evident in the water services sector, where management companies tend to focus more on the networks of larger cities. The latter are generally prioritized in the planning and execution of interventions, whether for renovation or maintenance, due to their higher population density and greater economic returns. Conversely, small towns are often overlooked, resulting in limited funding and modernization of their water distribution networks. This insufficient funding barely allows small towns to keep their water distribution networks operational in day-to-day management, making it almost impossible to invest in essential renovation and modernization efforts. The absence of monitoring, detection, and metering devices within the network prevents managers from gaining a comprehensive understanding of its current conditions, often leading to inefficient management. Such inefficiency is evident in the lack of awareness regarding the location of leaks, the unsystematic approach to pipes maintenance and replacement, the increased management and maintenance costs, and delays in the allocation of financial resources for these purposes. It is also reflected in the reliance on a reactive, post-intervention policy rather than a proactive, preventive approach, which could considerably reduce the financial burden on the system. During drought periods, small towns often rely on emergency measures, such as using water tankers to deliver water to residents. Such reliance stresses their vulnerability and weakens their resilience compared to larger cities. All these factors exacerbate the deteriorating condition of the WDN in small towns, rendering it less resilient, reliable, and effective. Basilicata region is no exception with 75% of its municipalities are small towns and leakage rate accounts for 60%, the highest in Italy. The mountainous terrain of the region makes small towns more isolated and dispersed, complicating the renovation and maintenance of the WDN and increasing associated costs.
Considering these challenges, small towns with limited financial resources must face significant issues such as reducing water and energy losses ensuring networks are resilient to climate change impacts. The introduction of technologies for pressure regulation and monitoring can significantly improve the management of water distribution networks, such as those analysed in this study.
Pressure monitoring and control provide several immediate advantages: on the one hand, optimal pressure management helps reduce water losses; on the other, a substantial improvement in informational capabilities enables the implementation of alert systems, allowing for timely interventions in case of malfunctions. This approach enhances infrastructure resilience, avoiding costly structural modifications. Despite its clear potential, small-scale entities often face challenges in adopting such solutions due to management complexities and high initial investment requirements. To address these challenges, this thesis focuses on the application of the Green Valve System (GVS), an integrated device that combines monitoring, pressure control, communication systems into a single solution that is fully energy self-sufficient. this study proposes a methodology to optimize the placement of devices within the network. Although the problem may appear theoretically straightforward, optimizing valve placement is a complex, nonlinear, and non-convex problem. For example, considering a network of 150 pipes, placing five PRVs would require evaluating over 591,600,030 possible combinations, not including the subsequent optimization of valve settings, which would further increase the number of combinations. This large search space highlights the importance of developing and applying advanced optimization methodologies capable of identifying practical and efficient solutions to enhance the sustainability and efficiency of water networks in small towns. In this regard, there are two main approaches to optimization: deterministic and metaheuristic methods. The deterministic approach, such as linear programming (LP) and nonlinear programming (NLP), guarantees finding the optimal solution. However, it requires prior knowledge of the problem and the relationships between its parameters. Additionally, it is characterized by slow convergence and is computationally expensive. These disadvantages have led to the emergence of metaheuristics, which are problem-independent, much faster, and computationally less costly.
In the contrary to blind Pure Random Search, the metaheuristic algorithms use the randomness in an intelligent and biased way (Stützle 1999). They do not guarantee the optimal solution, though, they offer a practical and near-optimal solution. Metaheuristics expands the exploration over new regions in the search space and find a balance between the exploitation and exploration capability over the search space (Blum and Roli 2003).
These algorithms have been widely used in many engineering fields to solve different optimization problems, thanks to their flexibility and capability of finding a near optimal solution for complex problem, where the full enumeration of feasible solutions is beyond the practical objectives.
The objective of this thesis is to reduce water losses and promote the sustainability of water distribution networks in small towns through the use of metaheuristic optimization algorithms and the implementation of green valves. The proposed approach has been validated on benchmark networks and applied to real water networks in two municipalities in the Basilicata region, southern Italy.
The thesis is structured as follows:
• Chapter 1: examines the challenges facing water distribution networks and describes innovative solutions to improve their efficiency, sustainability, and resilience.
• Chapter 2: provides a literature review of metaheuristic algorithms, highlighting their advantages in addressing complex optimization problems.
• Chapter 3: details the adopted methodology and the characteristics of the study area.
• Chapter 4: discusses the results obtained and their implications.
• Conclusions: summarizes the main findings of the research and offers perspectives for future developments
On the approximation properties of generalized Gamma-type operators in several function spaces
No full textIn the present paper we study a class of integral operators of probabilistic type, which are constructed by means of the generalized Gamma distribution. In particular, we discuss their approximation properties in weighted continuous functions spaces and Lp-spaces, providing some estimates of the rate of convergence by means of different moduli of smoothness as well as an asymptotic formula. The paper concludes with some illustrative examples