90 research outputs found
Pottery from Old Dongola (14th-18th century CE)
No full textThe files saved in .ods format present the results of the pottery studies carried out in the framework of the ERC Starting Grant "UMMA-Urban Metamorphosis of the Community of a Medieval African Capital City" in Old Dongola, Sudan. They were obtained during the pottery processing according to the protocol accepted for the Late Christian and Islamic pottery in Old Dongola (Wodzińska 2022). The project studied the transformations during the Christian and Islamic occupations of Old Dongola, a key political center in the Middle Nile Valley. It focused on pottery analysis to understand changes in vessel production and use, as well as their role in the region's socio-economic landscape.The file "DongolaPottery_ContextLogin" contains general information about the pottery recorded for each archaeological context, such as season, sector, square, context, unit (if applicable), dating, bag number (if applicable), inventory number (if applicable). The pottery is organized with quantity and weight data for sherds (total per context), handmade, wheel-made, and redeposited pottery fragments. The following fields contain remarks, date of processing and entry's author.The DongolaPottery_DiagnosticLog file is a detailed log of all diagnostic vessels recorded for each archaeological context. It contains all the information about the archaeological context as the other file. Description of each diagnostic pottery fragment includes class, type, vessel part, quantity, production technique, and fabric type. Decoration (type, place, color) and glaze, potmark descriptions occur if applicable. The following fields contain dimensions, weight, traces of use (if applicable), remarks, date of processing, and entry's author. The typology used in this dataset is based on Danys 2022 and a forthcoming publication by the same author.</p
Autonomous Approach and Landing Algorithms for Unmanned Aerial Vehicles
No full textIn recent years, several research activities have been developed in order to increase the autonomy features in Unmanned Aerial Vehicles (UAVs), to substitute human pilots in dangerous missions or simply in order to execute specific tasks more efficiently and cheaply. In particular, a significant research effort has been devoted to achieve high automation in the landing phase, so as to allow the landing of an aircraft without human intervention, also in presence of severe environmental disturbances. The worldwide research community agrees with the opportunity of the dual use of UAVs (for both military and civil purposes), for this reason it is very important to make the UAVs and their autolanding systems compliant with the actual and future rules and with the procedures regarding autonomous flight in ATM (Air Traffic Management) airspace in addition to the typical military aims of minimizing fuel, space or other important parameters during each autonomous task.
Developing autolanding systems with a desired level of reliability, accuracy and safety involves an evolution of all the subsystems related to the guide, navigation and control disciplines. The main drawbacks of the autolanding systems available at the state of art concern or the lack of adaptivity of the trajectory generation and tracking to unpredicted external events, such as varied environmental condition and unexpected threats to avoid, or the missed compliance with the guide lines imposed by certification authorities of the proposed technologies used to get the desired above mentioned adaptivity.
During his PhD period the author contributed to the development of an autonomous approach and landing system considering all the indispensable functionalities like: mission automation logic, runway data managing, sensor fusion for optimal estimation of vehicle state, trajectory generation and tracking considering optimality criteria, health management algorithms.
In particular the system addressed in this thesis is capable to perform a fully adaptive autonomous landing starting from any point of the three dimensional space. The main novel feature of this algorithm is that it generates on line, with a desired updating rate or at a specified event, the nominal trajectory for the aircraft, based on the actual state of the vehicle and on the desired state at touch down point. Main features of the autolanding system based on the implementation of the proposed algorithm are: on line trajectory re-planning in the landing phase, fully autonomy from remote pilot inputs, weakly instrumented landing runway (without ILS availability), ability to land starting from any point in the space and autonomous management of failures and/or adverse atmospheric conditions, decision-making logic evaluation for key-decisions regarding possible execution of altitude recovery manoeuvre based on the Differential GPS integrity signal and compatible with the functionalities made available by the future GNSS system.
All the algorithms developed allow reducing computational tractability of trajectory generation and tracking problems so as to be suitable for real time implementation and to still obtain a feasible (for the vehicle) robust and adaptive trajectory for the UAV.
All the activities related to the current study have been conducted at CIRA (Italian Aerospace Research Center) in the framework of the aeronautical TECVOL project whose aim is to develop innovative technologies for the autonomous flight. The autolanding system was developed by the TECVOL team and the author’s contribution to it will be outlined in the thesis.
Effectiveness of proposed algorithms has been then evaluated in real flight experiments, using the aeronautical flying demonstrator available at CIRA
Caminhando e cantando e seguindo a canção: o triste itinerário cantante do campesinato rumo ao Templo
No full textO presente artigo tem por objetivo analisar o Salmo 126 pela plataforma histórico-social. Tendo em vista que o material fora escrito em época do Segundo Templo, em torno de 350-300 a.E.C., ele carrega elementos que ajudam a identificar a luta do campesinato na história do povo de Israel ao retornar do exílio na Babilônia em época do domínio persa. Os versos registram as memórias dos deportados que se uniram aos demais no campo. Dois estágios negativos são observados a partir do verso 4: a) o sofrimento com o período de estiagem e; b) a política (econômica) persa, onde Judá deveria se concentrar na produção de vinho e azeite (como outros povos subjugados haveriam de focar em diferentes cultivos na terra) – o que prejudicaria os que viviam da cultura do cereal. No primeiro momento, a relação com a teologia do Templo, em que Iahweh seria responsável pela seca; no segundo momento, a relação entre o Templo e a política persa, cujo tema faz sobressaltar no verso 6: a canção da resistência do camponês/peregrino
Some problems in irregular ordinary differential equations
No full textWe study the non-autonomous ordinary differential equation x = f (t, x) in the
situation when the vector field f is of limited regularity, typically belonging to
a space LP (O,T; Lq (JRn)). Such equations arise naturally when switching from an
Eulerian to a Lagrangian viewpoint for the solutions of partial differential equations.
We discuss some measurability issues in the foundations of the theory of regular
Lagrangian flow solutions. Further, we examine the sensitivity of the choice of
representative vector field f on solutions of the ordinary differential equation and,
in particular, we demonstrate that every vector field can be altered on a set of
measure zero to introduce non-uniqueness of solutions.
We develop some geometric tools to quantify the behaviour of solutions,
notably a non-autonomous version of subset avoidance and the r-codimension print
that encodes the dimension of a subset S c JRn x [0, T] while distinguishing between
the spatial and temporal detail of S. We relate this notion of dimension to the more
familiar box-counting dimensions, for which we prove some new inequalities.
Finally, motivated by the issues with measurability that can arise with irregular
vector fields we prove some fundamental results in the theory of Bochner
integration in order to be able to manipulate the representatives of the equivalence
classes in LP (O,T; Lq (JRn))
: École d’été 2015 - Théorie géométrique de la mesure et calcul des variations : théorie et applications
No full textA celebrated theorem of Almgren shows that every integer rectifiable current which minimizes (locally) the area is a smooth submanifold except for a singular set of codimension at most 2. Almgren’s theorem is sharp in codimension higher than 1, because holomorphic subvarieties of Cn are area-minimizing. In fact the typical singularity of a 2-dimensional area-minimizing current is modelled by branch points of holomorphic curves. These singularities are rather difficult to analyze because they might be very high order phenomena.Take for instance the holomorphic curveΓ={(z,w)∈C2 :(z−w2)2 =w2015}.The origin is a singular point but in any neighborhood of it Γ is extremely close to two copies of the smooth submanifold {(z,w) : z = w2}: the “singular” behavior can be seen clearly only after we “mod out” such regular part.The most involved part of Almgren’s proof is the construction, for a general area- minimizing current, of what he calls the “center manifold”: a C3,α submanifold which approximates with a very high degree of precision the regular part of an area-minimizing current in a neighborhood of a singular point. A very interesting corollary of this construction is that we can conclude directly C3,α regularity around regular points: in contrast the “classical proof” shows first C1,α regularity and then boostraps using Schauder estimates.The construction of the center manifold is undoubtedly the most difficult part of Almgren’s proof and it alone takes more than 500 pages in his original monograph [1]. A much shorter derivation of the existence of a center manifold has been proposed recently by the author and Emanuele Spadaro in [3]. In this series of lectures I will highlight why one needs such an object and I will give some of the details of its construction in the simplified situation of regular points, following a self-contained account given in [2]. References[1] Frederick J. Almgren, Jr. Almgren’s big regularity paper, volume 1 of World Scientific Monograph Series in Mathematics. World Scientific Publishing Co. Inc., River Edge, NJ, 2000.[2] Camillo De Lellis and Emanuele Spadaro. Center manifold: a case study. Discrete Contin. Dyn. Syst., 31(4):1249–1272, 2011.[3] Camillo De Lellis and Emanuele Spadaro. Regularity of area-minimizing currents II: center manifold. Preprint, 2013.
O Templo de Salomão (IURD) como projeto de nova gestão identitária
No full textConsiderando a construção do Templo de Salomão (TdS) no bairro do Brás, na cidade de São Paulo, como o novo mo(vi)mento da Igreja Universal do Reino de Deus (IURD), o presente artigo tem por interesse analisar essa construção identitária que se utiliza de mecanismos do Primeiro Testamento. Numa linguagem que aqui é relacionada com a formação de um projeto de controle social (Platão / Marcel Detienne), o mito é apresentado como sua mais efetiva ferramenta e que se desenvolve a partir de uma hierarquia. Uma cidade defendida por mitólogos, com leis e discursos criados a fim de uniformizar seus cidadãos, serviria como um modelo teórico para se pensar o recente projeto (TdS) da IURD, quando regras bem distintas dos outros templos são determinadas e um projeto de controle (ou gestão) é formado diante de seus membros/frequentadores a fim de se aproximar do modelo do Primeiro Testamento, formando, assim, uma (possível) identidade neo-judaica
"Os Ungidos”, de Thomas Sowell. Relevância de sua publicação no Brasil para um debate sobre identitarismo
No full textResenha do livro:
SOWELL, Thomas. Os ungidos: a fantasia das políticas sociais progressistas. Tradução: Felipe Ahmed. São Paulo, LVM Editora, 2022. 344 p.
 
Os protestantismos (des)encarnados no Brasil: a relação com a política ontem e hoje
No full textResenha
“O PRESIDENTE PODE MISTURAR POLÍTICA E RELIGIÃO?” O SISTEMA POLÍTICO-TEOLÓGICO DO MESSIAS A PARTIR DA SÉRIE JOÃO 8:32
No full textIniciou-se, em 2019, uma série de postagens nas redes sociais do presidente Jair Messias Bolsonaro denominada “Da série João 8:32”, baseada no texto bíblico “E conhecereis a verdade e a verdade vos libertará”. O objetivo era legitimar as ações, decisões e opiniões políticas a partir do verso sagrado, também adotado em sua campanha presidencial. À luz da teoria dos sistemas políticos, de David Easton, este artigo propõe desenvolver como o presidente filtra (gatekeeper) os valores religiosos e outras informações e os devolve (feedback) para a sociedade (in-put), obtendo, assim, reações que ora legitimam seus atos somando apoios, ora fazendo-o reconsiderar tais decisões ou discursos
A Proof of Onsager\u27s Conjecture
No full textFor any due to [Eyink] and [Constantin, E, Titi], solves Onsager\u27s conjecture that the exponent marks the threshold for conservation of energy for weak solutions in the class . The previous best results were solutions in the class for , due to the author, and in the class for due to Buckmaster, De Lellis and Székelyhidi, both based on the method of convex integration developed for the incompressible Euler equations by De Lellis and Székelyhidi. The present proof combines the method of convex integration and a new gluing approximation technique. The convex integration part of the proof relies on the Mikado flows introduced by [Daneri, Székelyhidi] and the framework of estimates developed in the author\u27s previous work.References improved. Modified in response to referee
- …
