A covering problem over finite rings

AbstractGiven a finite commutative ring with identity A, define c(A,n,R) as the minimum cardinality of a subset H of An which satisfies the following property: every element in An differs in at most R coordinates from a multiple of an element in H. In this work, we determine the numbers c(Zm,n,0) for all integers m≥2 and n≥1. We also prove the relation c(S×A,n,1)≤c(S,n−1,0)c(A,n,1), where S=Fq or Zq and q is a prime power. As an application, an upper bound is obtained for c(Zpm,n,1), where p is a prime

Applications of String Theory: Non-perturbative Effects in Flux Compactifications and Effective Description of Statistical Systems

In this paper, which is a revised version of the author's PhD thesis, we analyze two different applications of string theory. In the first part, we focus on four dimensional compactifications of Type II string theories preserving N=1 supersymmetry, in presence of intersecting or magnetized D-branes. We show, through world-sheet methods, how the insertion of closed string background fluxes may modify the effective interactions on Dirichlet and Euclidean branes. In particular, we compute flux-induced fermionic masses. The generality of our results is exploited to determine the soft terms of the action on the instanton moduli space. Finally, we investigate how fluxes create new non-perturbative superpotential terms in presence of gauge and stringy instantons in SQCD-like models. The second part is devoted to the description of statistical systems through effective string models. In particular, we focus our attention on (d-1)-dimensional interfaces, present in particular statistical systems defined on compact d-dimensional spaces. We compute their exact partition function by resorting to standard covariant quantization of the Nambu-Goto theory, and we compare it with Monte Carlo data. Then, we propose an effective model to describe interfaces in 2d space and test it against the dimensional reduction of the Nambu-Goto description of the 2d interface.Comment: 159 pages, PhD thesi

14th CIRIAF National Congress – Energy, Environment and Sustainable Development

CIRIAF (Inter-University Research Center on Pollution and Environment “Mauro Felli” is a research center, based at the University of Perugia, which promotes interdisciplinary research activities in the fields of environmental pollution and its health and socio-economic effects, sustainable development, renewable and alternative energy, energy planning, and sustainable mobility. One hundred professors from fourteen different Italian universities are involved in the activities of the center. The CIRIAF National Congress (e.g., the fourteenth one in 2014), has become, over time, an important event for researchers and experts (engineers, physicists, chemists, architects, doctors, and economists). These individuals are not simply academics; they also hail from ministries, environmental agencies, and local authorities. The annual meeting in Perugia is an opportunity to discuss the issues related to energy, environment and sustainable development. After some editions were devoted to panel discussions and workshops, the 14th Congress, which took place in Perugia from 4-5 April 2014, returned to the formula of parallel technical sessions. The Congress was quite successful. Seventy-nine papers were presented during the Congress; these were divided into the following eight Sessions, in line with the congress tradition. The session topics are of great contemporary interest: Built Environment Quality and Indoor Pollution Energy and Environmental Certification of Buildings Artworks Preservation and Museum Plants Renewable and Alternative Energy Sources and Systems Pollution from Physical Agents (noise, vibrations, electromagnetic fields) Air and Water Pollution Sustainable Mobility Energy Planning and Environmental Impact As usual, the ceremony of the “Mauro Felli” award took place during the Congress. The award, established to honor the memory of the founder and first Director of CIRIAF, is intended for young graduates, Ph.D. students or researchers who have carried out research activities in the fields concerning pollution originating from physical agents, the effects of environmental pollution on humans or related issues. Thanks to an agreement with the international publishing house MDPI, I am happy to introduce to you a special issue of SUSTAINABILITY, which contains the best papers presented at the Congress. The Special Issue will include the best papers presented at the Congress. These were selected by the Scientific Committee with the help of the various Chairmen of the Sessions. The papers cover all the various aspects of sustainability, from an interdisciplinary point of view, with a strong emphasis on the link between energy production, use and conservation, and environmental impact

Management of bone defects with Bio-oss

Introduction: The defects in the alveolar bone might appear as a result of congenital malformations, traumatic injuries, periodontal disease, surgical traumas, chronic periapical changes and tumors from benign or malignant origin. The aim of this study was to provide solid and healthy area with application of Bio-Oss in the defect. Materials and methods: Based on the clinical diagnosisestablished by previously taken history, clinical examination and radiographic images oral-surgery interventions was made. To realize the aim of this work, augmentative material was implicated in the bone defects made in the patients after removal of follicular cyst, chronic periapical lesion, and parodontopathia. During the first and seventh day of the interventions, the patients have been followed through from aspect of possible development of local and general complications after the oral-surgery intervention. After period of one, three and six mount control x-ray was made. Results: Obtained results confirmed that: volume of the socket and defect of the bone was kept, fast revascularization was achieved, bone formation and slow resorption of the augmentative material was achieved, and period of normal healing without infection was also achieved. Conclusions: The augmentative materials used for treatment of bone defects besides their basic chemical and physical characteristics referring to their solubility in the body fluids, the transformation, modulation and resorption must be completely safe or secure, i.e. not to bring any risk of infection, immunological risk, physiological intolerance or inhibition of the process of restitutio ad integrum. In our study Bio-Oss was confirmed as augmentative material who had this characteristics. Keywords: bone defect, resorption of the bone, augmentative material, Bio-Os

Creating Through Mind and Emotions

The texts presented in Proportion Harmonies and Identities (PHI) Creating Through Mind and Emotions were compiled to establish a multidisciplinary platform for presenting, interacting, and disseminating research. This platform also aims to foster the awareness and discussion on Creating Through Mind and Emotions, focusing on different visions relevant to Architecture, Arts and Humanities, Design and Social Sciences, and its importance and benefits for the sense of identity, both individual and communal. The idea of Creating Through Mind and Emotions has been a powerful motor for development since the Western Early Modern Age. Its theoretical and practical foundations have become the working tools of scientists, philosophers, and artists, who seek strategies and policies to accelerate the development process in different contexts

Intelligence, Creativity and Fantasy

UID/HIS/04666/2019 This is the 2nd volume of PHI series, published by CRC Press, the 4th published by CRC Press and the 5th volume of PHI proceedings.The texts presented in Proportion Harmonies and Identities (PHI) - INTELLIGENCE, CREATIVITY AND FANTASY were compiled with the intent to establish a multidisciplinary platform for the presentation, interaction and dissemination of research. The aim is also to foster the awareness and discussion on the topics of Harmony and Proportion with a focus on different visions relevant to Architecture, Arts and Humanities, Design, Engineering, Social and Natural Sciences, and their importance and benefits for the sense of both individual and community identity. The idea of modernity has been a significant motor for development since the Western Early Modern Age. Its theoretical and practical foundations have become the working tools of scientists, philosophers, and artists, who seek strategies and policies to accelerate the development process in different contexts.authorsversionpublishe