29 research outputs found
Theoretical results of one class of multiderivative methods through order stars
Order stars are applied to Brown (K,L) methods. They are displayed pictorially for a selection of methods and are used to provide succinct proofs of existing results. Asymptotic results concerning their stability are also presented
DESENVOLVIMENTO DE UMA PLATAFORMA DE SOFTWARE PARA A MODELAGEM DIGITAL DE TERRENOS BASEADA EM TIN
Superfícies topográficas podem ser representadas com um bom grau de precisão pormeio de mapas. No entanto, estes nem sempre são as melhores ferramentas para acompreensão de relevos mais complexos. Nesse sentido, a maior contribuição dessetrabalho é a especificação e implementação da arquitetura de uma plataforma desoftware opensource voltado para a representação de modelos digitais de terrenosbaseado em TIN (Triangular Irregular Network), segundo os paradigmas daprogramação orientada a objetos e programação genérica e que possibilitaram aintegração de várias ferramentas de linguagem aberta (opensource), tais comoGDAL, OGR, OpenGL, OpenSceneGraph e Qt. Além disso, o núcleo derepresentação da arquitetura tem a capacidade de trabalhar com múltiplas estruturasde dados topológicas que permitem extrair em tempo constante, todas as relações deconectividade entre as entidades vértices, arestas e faces, presentes numa subdivisãoplanar triangular, facilitando enormemente a implementação de aplicações de temporeal. Esta capacidade é muito importante, por exemplo, na utilização de dados delevantamentos a laser (Lidar, ALS, TLS), possibilitando a geração de modelos demalhas triangulares da ordem de milhões de pontos
Results of pars plana vitrectomy after complicated phacoemulsification surgery
Purpose: To identify the causes and outcomes of pars plana vitrectomy (PPV) in patients undergoing phacoemulsification with intraoperative complication and to analyze whether the interval between phacoemulsification and PPV interferes with best-corrected final visual acuity. Methods: This descriptive and retrospective analytical study was conducted in Paraná Eye Hospital in 2013. Data were collected from medical records of 38 patients who underwent complicated phacoemulsification and also required PPV. Results: The most frequent complication as a result of phacoemulsification was posterior capsule rupture, observed in 35 patients (92.10%), followed by capsular bag detachment, in three patients (7.89%). Twenty-eight patients (73.68%) had cortical fragments that were removed during PPV. Twelve patients (31.57%) had their intraocular lens repositioned. PPV was performed on the same day of phacoemulsification in one patient (2.63%), within 1 week in 15 patients (39.47%), between 1 week and 1 month in 13 patients (34.21%), and 1 month after phacoemulsification in 9 patients (23.68%). Conclusion: This study is in agreement with worldwide literature, asserting that major complications of phacoemulsification are posterior capsule rupture and capsular bag detachment, and in addition, there is an improvement in the final visual acuity in almost half the cases, even when there are complications during modern cataract surgery, when complementary appropriate treatment is provided
Transport analytics in action: a cloud-based decision support system for efficient city bus transportation
Optimising city bus transport operations helps conserve fuel by providing the urban transport service as efficiently as possible. This study develops a Cloud-based Decision Support System (C-DSS) for transport analytics. The C-DSS is based on an intelligent model on location of depots for opening new depots and/or closing a few existing depots and allocation of city-buses to depots. The C-DSS is built on the Cloud Computing architecture with three layers and includes an efficient and simple greedy heuristic algorithm. Using modern information and communications technology tools, the proposed C-DSS minimizes the cost of city bus transport operations and in turn to reduce fuel consumption and CO2 emissions in urban passenger transport. The proposed C-DSS is demonstrated for its workability and evaluated for its performance on 25 large scale pseudo data generated based on the observation from Bangalore Metropolitan Transport Corporation (BMTC) in India
A THEORETICAL RESULT ON PHASE-LAG
We prove a Theoretical result which relates phase-lag to the error constant of a numerical method for periodic problem y'' = f(x, y)
Desenvolvimento de uma plataforma de software para a modelagem digital de terrenos baseada em TIN
Topographical surfaces can be represented with a good degree of accuracy by means of maps. However these are not always the best tools for the understanding of more complex reliefs. In this sense, the greatest contribution of this work is to specify and to implement the architecture of an opensource software system capable of representing TIN (Triangular Irregular Network) based digital terrain models. The system implementation follows the object oriented programming and generic paradigms enabling the integration of various opensource tools such as GDAL, OGR, OpenGL, OpenSceneGraph and Qt. Furthermore, the representation core of the system has the ability to work with multiple topological data structures from which can be extracted, in constant time, all the connectivity relations between the entities vertices, edges and faces existing in a planar triangulation what helps enormously the implementation for real time applications. This is an important capability, for example, in the use of laser survey data (Lidar, ALS, TLS), allowing for the generation of triangular mesh models in the order of millions of points.Superfícies topográficas podem ser representadas com um bom grau de precisão por meio de mapas. No entanto, estes nem sempre são as melhores ferramentas para a compreensão de relevos mais complexos. Nesse sentido, a maior contribuição desse trabalho é a especificação e implementação da arquitetura de uma plataforma de software opensource voltado para a representação de modelos digitais de terrenos baseado em TIN (Triangular Irregular Network), segundo os paradigmas da programação orientada a objetos e programação genérica e que possibilitaram a integração de várias ferramentas de linguagem aberta (opensource), tais como GDAL, OGR, OpenGL, OpenSceneGraph e Qt. Além disso, o núcleo de representação da arquitetura tem a capacidade de trabalhar com múltiplas estruturas de dados topológicas que permitem extrair em tempo constante, todas as relações de conectividade entre as entidades vértices, arestas e faces, presentes numa subdivisão planar triangular, facilitando enormemente a implementação de aplicações de tempo real. Esta capacidade é muito importante, por exemplo, na utilização de dados de levantamentos a laser (Lidar, ALS, TLS), possibilitando a geração de modelos de malhas triangulares da ordem de milhões de pontos
Palindromic and perturbed polynomials: zeros location
We give necessary and sufficient conditions for all zeros of the palindromic polynomial R(z)=1+lambda(z+z (2)+aEuro broken vertical bar+z (n-1))+z (n) , , to be on the unit circle and we find for which S(z)=R(z)+gamma z (n) , n natural, has all its zeros in the closed unit disc.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP