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Wiskundecollega Dirk Danckaert ontdekte onlangs een merkwaardig filmpje op het internet (https://www.youtube.com/user/numberphile) waarin Ed Copland een gedachte-experiment uitlegt waarmee hij de decimalen van \(\pi\) berekent aan de hand van twee botsende ballen. De proef is in realiteit moeilijk uitvoerbaar omdat de massaverhouding van de twee puntmassa's zeer groot moet zijn en omdat de botsingen ook volledig elastisch moeten zijn. De verklaring van Copland voor dit fenomeen trok me sterk aan omdat ze een link legt met lineaire transformaties in vectorruimten, met eigenwaarden en met eigenvectoren. Aangemoedigd door de eenvoud van het eindresultaat van deze afleiding, ging Dirk Danckaert op zoek naar een compactere verklaring. Die vond hij door de vectorruimte van Ed Copland uit te breiden tot een inproductruimte.

Ehsan Ullah's CV

Handouts should be made to complement serious presentations. The purpose of this handout is to summarize the Edward Tufte lecture on June 16th, 2016 in Chicago. Tufte began and ended his lecture wordlessly with a clip from the Music Animation Machine project and it is one of the metaphors used for the beautiful potential of clarity in information display. Relatively large amounts of information are displayed in context; the data contains the past, present, and future, and in a short matter of time, the viewer can predict the duration, pitch and sound of the notes heard based on the visual experience of the data. This is a beautiful metaphor for the potential of immediate visual context in multiscale imaging.

A study tool. Equations are mostly listed without a description of what they represent. Topics are detailed based on problems. Usage: To prepare for the Calculus BC exam, go through topics one at a time and mentally describe the problem, process, and equations involved. If you get stuck - look up the answer and start again from the top. When you can get through the entire sheet - you're ready! Do the same with the equation list - describing exactly what type of problems you might need the equation for. Do not use notes in conjunction with the review sheet. Look up the answer - close the book and start again! You can thank me later.

Em um cenário onde a execução dos processos são altamente dependentes de recursos de Tecnologia da Informação (TI), a forma de entrega dos acessos é elemento vital para garantia da proteção e confiabilidade das informações que viabilizam a execução das tarefas desses processos. Neste contexto, o sistema ERP de uma organização é item de configuração chave, demandando de sólido gerenciamento do controle de acesso, manipulação e armazenamento das informações. Este artigo aborda, no contexto de uma organização brasileira de capital aberto, o método de controle de acesso aplicado em conjunto com o processo de gestão de riscos, que juntos proporcionam uma visão singular sobre riscos diversos que podem ser até mesmo de fraudes financeiras. O acumulo de permissões, ou ainda, a concessão de acessos sem prévia análise dos riscos de segregação de função (SoD - Segregation of Duties) podem trazer consequências graves à organização. Neste intento, buscou-se uma contextualização de acordo com a legislação vigente, processos necessários, tomando como exemplo um sub processo da área financeira de uma organização fictícia que utiliza o sistema SAP.

With the aim to develop more efficient aircraft configurations, the Blended-Wing-Body (BWB) unmanned aerial vehicles have grown attention in recent years. Compare to conventional aircraft configurations, the BWB structure has several advantages in aerody- namics and fuel efficiency. Topology optimization (TO) is also a relatively new structure optimization approach which has applied successfully in automotive industry for a consid- erable time. In this paper, topology optimization method will be applied on a special BWB structure UAV called BITU on both 2D and 3D models in ABAQUS. The optimization goal is to minimize compliance energy under specified loading and boundary conditions which will be computed in modeling and simulation section. Finally, optimized result compared to initial design will demonstrate TO is a rational and efficient design tool for structure optimization, especially in Aircraft industry.

Resume in LuaLatex Resume in LuaLatex using json sources. Work in progress on HTML page based on the same json sources.

Presentation for Final Project - Theory of Computation

A new algorithm can speed up searching anything as a generalization of B/R-Trees