Search for: structured-tree
0.008 seconds

    Numerical and One Dimensional Modeling of Cardiovascular System Along with Lumped Parameter Modeling of the Heart

    , M.Sc. Thesis Sharif University of Technology Salehi, Sarah (Author) ; Firoozabadi, Bahar (Supervisor) ; Saidi, Mohammad Saeed (Co-Advisor)
    Cardiovascular diseases are major causes of morbidity and mortality in the world. In order to prevent or reduce these diseases, engineers and scientists are concerned to find solutions. In this way, it is important to know about the blood flow and its changes in various diseases. By using simulation methods, diagnosis can be very easier. In this study, a system of arterial tree consisting of 93 systemic arteries along with 7 pulmonary arteries is considered. In other words, this model contains 100 systemic and pulmonary arteries that encompass central and peripheral arteries. Other parts of this model are cerebral vasculature and coronary arteries. Cerebral arteries, also called circle of... 

    Numerical and 1-D modeling of pulmonary circulation along with lumped parameter modeling of the heart

    , Article 2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013 ; December , 2013 , Pages 93-97 Salehi, S. S ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
    IEEE Computer Society  2013
    A one dimensional model of the pulmonary arterial network along with systemic circulation was introduced to quantify the human pulmonary artery hemodynamics. A lumped parameter model of the right ventricle was used as the inlet boundary condition. A time varying elastance related the volume and pressure of the right ventricle was imposed in the model. By using a four element Windkessel model, blood flow rate throughout the right ventricle was in hand. An asymmetric structured tree was chosen as the outlet boundary conditions. Simulation was based on solving one-dimensional equations of conservation of mass and momentum by using finite volume method. Blood flow rate, pressure and velocity... 

    Numerical and 1-D modeling of systemic circulation along with cerebral vasculature

    , Article 2012 19th Iranian Conference of Biomedical Engineering, ICBME 2012 ; 2012 , Pages 17-21 ; 9781467331302 (ISBN) Salehi, S. S ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
    The brain is one of the vital organs in the body. The main cerebral distribution center of blood flow in the brain is the circle of Willis (CoW). In more than 50% of healthy brains and in more than 80% of dysfunctional ones, at least one artery of the circle of Willis is absent or underdeveloped. These variations reduce the collateral flow availability and increase the risk of stroke and transient ischemic attack in patients with atherosclerosis. Thus it is essential to simulate the circle of Willis and investigate the effects of stenosis. In this work the systemic arteries along with the circle of Willis are simulated using the finite volume method and one-dimensional equations of... 

    1 + ϵ approximation of tree edit distance in quadratic time

    , Article 51st Annual ACM SIGACT Symposium on Theory of Computing, STOC 2019, 23 June 2019 through 26 June 2019 ; 2019 , Pages 709-720 ; 07378017 (ISSN); 9781450367059 (ISBN) Boroujeni, M ; Ghodsi, M ; Hajiaghayi, M ; Seddighin, S ; Sharif University of Technology
    Association for Computing Machinery  2019
    Edit distance is one of the most fundamental problems in computer science. Tree edit distance is a natural generalization of edit distance to ordered rooted trees. Such a generalization extends the applications of edit distance to areas such as computational biology, structured data analysis (e.g., XML), image analysis, and compiler optimization. Perhaps the most notable application of tree edit distance is in the analysis of RNA molecules in computational biology where the secondary structure of RNA is typically represented as a rooted tree. The best-known solution for tree edit distance runs in cubic time. Recently, Bringmann et al. show that an O(n2.99) algorithm for weighted tree edit... 

    Tree-Based method for classifying websites using extended hidden markov models

    , Article 13th Pacific-Asia Conference on Knowledge Discovery and Data Mining, PAKDD 2009, Bangkok, 27 April 2009 through 30 April 2009 ; Volume 5476 LNAI , 2009 , Pages 780-787 ; 03029743 (ISSN); 3642013066 (ISBN); 9783642013065 (ISBN) Yazdani, M ; Eftekhar, M ; Abolhassani, H ; National Electronics and Computer Technology Center (NECTEC); Thailand Convention and Exhibition Bureau (TCEB); Air Force Office of Scientific Research,; Asian Office of Aerospace Research and Development (AFOSR/AOARD) ; Sharif University of Technology
    One important problem proposed recently in the field of web mining is website classification problem. The complexity together with the necessity to have accurate and fast algorithms yield to many attempts in this field, but there is a long way to solve these problems efficiently, yet. The importance of the problem encouraged us to work on a new approach as a solution. We use the content of web pages together with the link structure between them to improve the accuracy of results. In this work we use Naïve-bayes models for each predefined webpage class and an extended version of Hidden Markov Model is used as website class models. A few sample websites are adopted as seeds to calculate...