IA Scholar Query: Planar Map Graphs.
https://scholar.archive.org/
Internet Archive Scholar query results feedeninfo@archive.orgSat, 31 Dec 2022 00:00:00 GMTfatcat-scholarhttps://scholar.archive.org/help1440Area-Optimal Simple Polygonalizations: The CG Challenge 2019
https://scholar.archive.org/work/ecyawviv5fapxkan7qzuh7u7fe
We give an overview of theoretical and practical aspects of finding a simple polygon of minimum ( Min-Area ) or maximum ( Max-Area ) possible area for a given set of n points in the plane. Both problems are known to be NP -hard and were the subject of the 2019 Computational Geometry Challenge, which presented the quest of finding good solutions to more than 200 instances, ranging from n = 10 all the way to n = 1, 000, 000.Erik D. Demaine, Sndor P. Fekete, Phillip Keldenich, Dominik Krupke, Joseph S. B. Mitchellwork_ecyawviv5fapxkan7qzuh7u7feSat, 31 Dec 2022 00:00:00 GMTCHRONOLOGY OF EVENTS
https://scholar.archive.org/work/wvsabzssobfcrhggspmfh7zagu
In this chronology we list the most impor tant publications and events that are featured in this volume. Harvard College ( later, Harvard University) is founded in Cambridge, Mas sa chu setts. The Collegiate School ( later, Yale University) is founded near New Haven, Connecticut. Leonhard Euler solves the Königsberg bridges prob lem. The College of New Jersey ( later, Prince ton University) is founded in New Jersey. Euler states his "polyhedron formula", F + V = E + 2. 1812-13 Simon-Antoine-Jean L'Huilier extends Euler's formula to orientable surfaces. King's College ( later, the University of Toronto) is founded. Gustav R. Kirchhoff writes on electrical networks and introduces spanning trees. Francis Guthrie poses the four color prob lem for maps. Thomas P. Kirkman and William R. Hamilton investigate "Hamiltonian cycles" on polyhedra. Arthur Cayley writes his first paper on trees. The Mas sa chu setts Institute of Technology (MIT) is founded in Boston. The first doctoral degrees are awarded, at Yale College. Johann B. Listing discusses "spatial complexes" in topology. The Morrill Act is passed, allowing for expansion in higher education. Cayley enumerates certain chemical molecules. xiv CHRONOLOGY OF EVENTS Now begin "The First Hundred Years" that are the focus of this book Johns Hopkins University is founded in Baltimore, Mary land, and James Joseph Sylvester is appointed the first professor of mathe matics. The American Journal of Mathe matics is launched. Arthur Cayley introduces "Cayley color graphs" and revives the four color prob lem at a meeting of the London Mathematical Society. James Joseph Sylvester writes on the "new atomic theory" and introduces the word "graph". Cayley shows that the four color prob lem can be restricted to cubic maps. Alfred B. Kempe proposes a proof of the four color theorem in the American Journal of Mathe matics, and William E. Story comments on Kempe's paper. Peter Guthrie Tait reformulates the four color prob lem in terms of coloring the bound aries of a cubic map. Tait conjectures that every cubic polyhedron has a Hamiltonian cycle. The New York Mathematical Society is founded. Cayley pre sents his n n − 2 result on the number of labeled trees. The University of Chicago is founded. Percy J. Heawood points out the error in Kempe's proof of the four color theorem, proves the five color theorem, and discusses the coloring of maps on orientable surfaces. Lothar Heffter investigates the coloring of maps on orientable surfaces, and points out the omission in Heawood's paper, leading to the "Heawood conjecture". Julius Petersen discusses the factorization of regular graphs. The New York Mathematical Society is renamed "The American Mathematical Society". Gaston Tarry pre sents a method for tracing a maze.work_wvsabzssobfcrhggspmfh7zaguSat, 31 Dec 2022 00:00:00 GMTLearning Unsupervised Hierarchies of Audio Concepts
https://scholar.archive.org/work/gojab4eqqrf35csqhposiyl27y
Music signals are difficult to interpret from their low-level features, perhaps even more than images: e.g. highlighting part of a spectrogram or an image is often insufficient to convey high-level ideas that are genuinely relevant to humans. In computer vision, concept learning was therein proposed to adjust explanations to the right abstraction level (e.g. detect clinical concepts from radiographs). These methods have yet to be used for MIR.In this paper, we adapt concept learning to the realm of music, with its particularities. For instance, music concepts are typically non-independent and of mixed nature (e.g. genre, instruments, mood), unlike previous work that assumed disentangled concepts.We propose a method to learn numerous music concepts from audio and then automatically hierarchise them to expose their mutual relationships. We conduct experiments on datasets of playlists from a music streaming service, serving as a few annotated examples for diverse concepts. Evaluations show that the mined hierarchies are aligned with both ground-truth hierarchies of concepts -- when available -- and with proxy sources of concept similarity in the general case.Darius Afchar, Romain Hennequin, Vincent Guiguework_gojab4eqqrf35csqhposiyl27ySun, 04 Dec 2022 00:00:00 GMTTowards a predictive multi-phase model for alpine mass movements and process cascades
https://scholar.archive.org/work/ckh43oqgjjanjgntl3spacckuy
Alpine mass movements can generate process cascades involving different materials including rock, ice, snow, and water. Numerical modelling is an essential tool for the quantification of natural hazards. Yet, state-of-the-art operational models are based on parameter back-calculation and thus reach their limits when facing unprecedented or complex events. Here, we advance our predictive capabilities for mass movements and process cascades on the basis of a three-dimensional numerical model, coupling fundamental conservation laws to finite strain elastoplasticity. In this framework, model parameters have a true physical meaning and can be evaluated from material testing, thus conferring to the model a strong predictive nature. Through its hybrid Eulerian-Lagrangian character, our approach naturally reproduces fractures and collisions, erosion/deposition phenomena, and multi-phase interactions, which finally grant accurate simulations of complex dynamics. Four benchmark simulations demonstrate the physical detail of the model and its applicability to real-world full-scale events, including various materials and ranging through five orders of magnitude in volume. In the future, our model can support risk-management strategies through predictions of the impact of potentially catastrophic cascading mass movements at vulnerable sites.Alessandro Cicoira, L Blatny, X Li, B Trottet, J Gaumework_ckh43oqgjjanjgntl3spacckuyThu, 01 Dec 2022 00:00:00 GMTLoss of the Bardet-Biedl protein Bbs1 alters photoreceptor outer segment protein and lipid composition
https://scholar.archive.org/work/etptrggjizhrbcovlretf7iqau
Primary cilia are key sensory organelles whose dysfunction leads to ciliopathy disorders such as Bardet-Biedl syndrome (BBS). Retinal degeneration is common in ciliopathies, since the outer segments (OSs) of photoreceptors are highly specialized primary cilia. BBS1, encoded by the most commonly mutated BBS-associated gene, is part of the BBSome protein complex. Using a bbs1 zebrafish mutant, we show that retinal development and photoreceptor differentiation are unaffected by Bbs1-loss, supported by an initially unaffected transcriptome. Quantitative proteomics and lipidomics on samples enriched for isolated OSs show that Bbs1 is required for BBSome-complex stability and that Bbs1-loss leads to accumulation of membrane-associated proteins in OSs, with enrichment in proteins involved in lipid homeostasis. Disruption of the tightly regulated OS lipid composition with increased OS cholesterol content are paralleled by early functional visual deficits, which precede progressive OS morphological anomalies. Our findings identify a role for Bbs1/BBSome in OS lipid homeostasis, suggesting a pathomechanism underlying retinal degeneration in BBS.Markus Masek, Christelle Etard, Claudia Hofmann, Andreas J Hülsmeier, Jingjing Zang, Masanari Takamiya, Matthias Gesemann, Stephan C F Neuhauss, Thorsten Hornemann, Uwe Strähle, Ruxandra Bachmann-Gagescuwork_etptrggjizhrbcovlretf7iqauThu, 01 Dec 2022 00:00:00 GMTMOLECULAR STRUCTURE, NBO AND TD-DFT ANALYSIS OF 4-METHYL-3-FURALDEHYDE BASED ON DFT CALCULATIONS
https://scholar.archive.org/work/jl42orhukzckrp5tyx72iryiey
In this study, molecular structure of 4-methyl-3-furaldehyde (4M3F) was analyzed using density functional theory (DFT) with level of B3LYP/6-311G++(d,p). As a result of the scanning of the CCC=O dihedral angle, two conformers (trans and cis) were found at minimum energy and the trans was more stable than the cis at ca. 6.4 kJ mol-1. Time dependent DFT (TD-DFT) calculations have been used to calculate the low-energy excited states energies and oscillator strengths. As a result of calculations, it was found that the highest transition probability and most effective oscillator strength were in the S0→S3 singlet state for both conformers. This excitation energy corresponds to 5.9 eV for the trans conformer, while it is around 5.6 eV for the cis conformer. The change in electron density in bonding-antibonding orbitals and their interactions as well as stabilization energies E(2) and natural atomic charges were calculated by Natural Bond Orbital (NBO) analysis. Electronic properties were analyzed using HOMO and LUMO energies.Nihal Kuswork_jl42orhukzckrp5tyx72iryieyThu, 01 Dec 2022 00:00:00 GMTHoneycomb Tessellations and Graded Permutohedral Blades
https://scholar.archive.org/work/duhevmby4ncszjj7wjhflwhgh4
We initiate the study of certain cyclically skewed tropical hyperplanes, called permutohedral blades by A. Ocneanu, and we make connections matroid theory, tropical geometry, moduli spaces and scattering amplitudes. We study two families of piecewise constant functions on ℝ^n-1 taking values in {0,1} and n ={1,2,...,n}, called respectively characteristic functions and graduated functions. We show that their codimension-one level sets exactly permutohedral blades. Using ring-theoretic arguments we show that a blade decomposes as a Minkowski sum of tripods and one-dimensional subspaces. For each triangulation of a cyclically oriented polygon there exists such a factorization. In the language of tropical geometry, this constructs a tropical hypersurface as a Minkowski sum of tropical lines. We use the principle of inclusion/exclusion to construct a collection of piecewise constant functions of blades which we enumerate by the dimension of the support of the function. On the induced ℚ-vector space one has an induced grading; this grading is compatible with various quotient spaces appearing in algebra, topology and scattering amplitudes. This vector space maps homomorphically onto the so-called Δ-algebra, which appears in the study of non-planar MHV leading singularities, leading to non-planar analogs of the square move for plabic graphs for G(2,n), called sphere moves. We give a closed formula for the graded dimension of the basis. It is shown in an Appendix by Donghyun Kim that the coefficients appearing in the numerator of the generating function for the graded dimension are symmetric, and that they sum to (2j)!/j!.Nick Earlywork_duhevmby4ncszjj7wjhflwhgh4Wed, 30 Nov 2022 00:00:00 GMTSmart Cities and Architectural Structures: Communicational and Informational Space
https://scholar.archive.org/work/cbbp3g3255en3kvyflybpyig4y
The expectations for shaping the urban landscape toward the ethical and aesthetic values of democracy are seen as the main challenge of an intelligent environment, made possible via information and communication technologies. Consequently, architecture's tendency to embrace digital media strives to create innovative and sustainable infrastructure. This approach aims for an argumentative theoretical analysis of aesthetics and communication sciences. The focus is on the context that continuously evolves living traditions persuaded by innovation that modifies and facilitates the evolution of society. The approach is also supposed to be a constantly evolving practice that engenders interaction between past, present, and future, configuring a unique urban landscape. The goal is about the metropolis as a collective achievement, seeking innovation through technologies while preserving tradition. Therefore, the convergence between architecture, technology, and new media requires the consideration of two viewpoints in this analysis. The first is the adopted architectural spatial models. The second is the transformative structure through new media, creating realities, intelligent environments, and interactive communities. Under these two directions, the artificial environment and imagined configuration through digital media are discussed, considering that technology overcame natural boundaries: the leitmotif of human cultural development.Christiane Wagnerwork_cbbp3g3255en3kvyflybpyig4yTue, 29 Nov 2022 00:00:00 GMTVisual SLAM: What Are the Current Trends and What to Expect?
https://scholar.archive.org/work/ehqztjcdebgv3cx3xbbv273bb4
In recent years, Simultaneous Localization and Mapping (SLAM) systems have shown significant performance, accuracy, and efficiency gain. In this regard, Visual Simultaneous Localization and Mapping (VSLAM) methods refer to the SLAM approaches that employ cameras for pose estimation and map reconstruction and are preferred over Light Detection And Ranging (LiDAR)-based methods due to their lighter weight, lower acquisition costs, and richer environment representation. Hence, several VSLAM approaches have evolved using different camera types (e.g., monocular or stereo), and have been tested on various datasets (e.g., Technische Universität München (TUM) RGB-D or European Robotics Challenge (EuRoC)) and in different conditions (i.e., indoors and outdoors), and employ multiple methodologies to have a better understanding of their surroundings. The mentioned variations have made this topic popular for researchers and have resulted in various methods. In this regard, the primary intent of this paper is to assimilate the wide range of works in VSLAM and present their recent advances, along with discussing the existing challenges and trends. This survey is worthwhile to give a big picture of the current focuses in robotics and VSLAM fields based on the concentrated resolutions and objectives of the state-of-the-art. This paper provides an in-depth literature survey of fifty impactful articles published in the VSLAMs domain. The mentioned manuscripts have been classified by different characteristics, including the novelty domain, objectives, employed algorithms, and semantic level. The paper also discusses the current trends and contemporary directions of VSLAM techniques that may help researchers investigate them.Ali Tourani, Hriday Bavle, Jose Luis Sanchez-Lopez, Holger Vooswork_ehqztjcdebgv3cx3xbbv273bb4Tue, 29 Nov 2022 00:00:00 GMTAn Exact Hypergraph Matching algorithm for posture identification in embryonic C. elegans
https://scholar.archive.org/work/qobmv5tq7za2jdaja5fs6ywayu
The nematode Caenorhabditis elegans (C. elegans) is a model organism used frequently in developmental biology and neurobiology [White, (1986), Sulston, (1983), Chisholm, (2016) and Rapti, (2020)]. The C. elegans embryo can be used for cell tracking studies to understand how cell movement drives the development of specific embryonic tissues. Analyses in late-stage development are complicated by bouts of rapid twitching motions which invalidate traditional cell tracking approaches. However, the embryo possesses a small set of cells which may be identified, thereby defining the coiled embryo's posture [Christensen, 2015]. The posture serves as a frame of reference, facilitating cell tracking even in the presence of twitching. Posture identification is nevertheless challenging due to the complete repositioning of the embryo between sampled images. Current approaches to posture identification rely on time-consuming manual efforts by trained users which limits the efficiency of subsequent cell tracking. Here, we cast posture identification as a point-set matching task in which coordinates of seam cell nuclei are identified to jointly recover the posture. Most point-set matching methods comprise coherent point transformations that use low order objective functions [Zhou, (2016) and Zhang, (2019)]. Hypergraphs, an extension of traditional graphs, allow more intricate modeling of relationships between objects, yet existing hypergraphical point-set matching methods are limited to heuristic algorithms which do not easily scale to handle higher degree hypergraphs [Duchenne, (2010), Chertok, (2010) and Lee, (2011)]. Our algorithm, Exact Hypergraph Matching (EHGM), adapts the classical branch-and-bound paradigm to dynamically identify a globally optimal correspondence between point-sets under an arbitrarily intricate hypergraphical model. EHGM with hypergraphical models inspired by C. elegans embryo shape identified posture more accurately (56%) than established point-set matching methods (27%), correctly identifying twice as many sampled postures as a leading graphical approach. Posterior region seeding empowered EHGM to correctly identify 78% of postures while reducing runtime, demonstrating the efficacy of the method on a cutting-edge problem in developmental biology.Andrew Lauziere, Ryan Christensen, Hari Shroff, Radu Balanwork_qobmv5tq7za2jdaja5fs6ywayuTue, 29 Nov 2022 00:00:00 GMTConstructive proofs for localized radial solutions of semilinear elliptic systems on ℝ^d
https://scholar.archive.org/work/t2jkhvqwere73cigkog5wk23ei
Ground state solutions of elliptic problems have been analyzed extensively in the theory of partial differential equations, as they represent fundamental spatial patterns in many model equations. While the results for scalar equations, as well as certain specific classes of elliptic systems, are comprehensive, much less is known about these localized solutions in generic system of nonlinear elliptic equations. In this paper we present a general method to prove constructively the existence of localized radially symmetric solutions of elliptic systems on ℝ^d. Such solutions are essentially described by systems of non-autonomous ordinary differential equations. We study these systems using dynamical systems theory and computer-assisted proof techniques, combining a suitably chosen Lyapunov-Perron operator with a Newton-Kantorovich type theorem. We demonstrate the power of this methodology by proving specific localized radial solutions of the cubic Klein-Gordon equation on ℝ^3, the Swift-Hohenberg equation on ℝ^2, and a three-component FitzHugh-Nagumo system on ℝ^2. These results illustrate that ground state solutions in a wide range of elliptic systems are tractable through constructive proofs.Jan Bouwe van den Berg, Olivier Hénot, Jean-Philippe Lessardwork_t2jkhvqwere73cigkog5wk23eiTue, 29 Nov 2022 00:00:00 GMTTridendriform algebras on hypergraph polytopes
https://scholar.archive.org/work/coup5svwtjddjfbx27luh5c5bm
We extend the works of Loday-Ronco and Burgunder-Ronco on the tridendriform decomposition of the shuffle product on the faces of associahedra and permutohedra, to other families of hypergraph polytopes (or nestohedra), including simplices, hypercubes and some new families. We also extend the shuffle product to take more than two arguments, and define accordingly a new algebraic structure, that we call polydendriform, from which the original tridendriform equations can be crisply synthesized.Pierre-Louis Curien, Bérénice Delcroix-Oger, Jovana Obradovićwork_coup5svwtjddjfbx27luh5c5bmTue, 29 Nov 2022 00:00:00 GMTStable capillary hypersurfaces and the partitioning problem in balls with radial weights
https://scholar.archive.org/work/bdwo6siq7jd4hfrtznqy36b2xa
In a round ball B⊂ℝ^n+1 endowed with an O(n+1)-invariant metric we consider a radial function that weights volume and area. We prove that a compact two-sided hypersurface in B which is stable capillary in weighted sense and symmetric about some line containing the center of B is homeomorphic to a closed n-dimensional disk. When combined with Hsiang symmetrization and other stability results this allows to deduce that the interior boundary of any isoperimetric region in B for the Gaussian weight is a closed n-disk of revolution. For n=2 we also show that a compact weighted stable capillary surface in B of genus 0 is a closed disk of revolution.César Rosaleswork_bdwo6siq7jd4hfrtznqy36b2xaTue, 29 Nov 2022 00:00:00 GMTThe human digital twin brain in the resting state and in action
https://scholar.archive.org/work/5eedqhtevzhplhv4x53oi2bg54
We simulate the human brain at the scale of up to 86 billion neurons, i.e., digital twin brain (DTB), which mimics certain aspects of its biological counterpart both in the resting state and in action. A novel routing communication layout between 10,000 GPUs to implement simulations and a hierarchical mesoscale data assimilation method to be capable to achieve more than trillions of parameters from the estimated hyperparameters are developed. The constructed DTB is able to track its resting-state biological counterpart with a very high correlation (0.9). The DTB provides a testbed for various "dry" experiments in neuroscience and medicine and illustrated in two examples: exploring the information flow in our brain and testing deep brain stimulation mechanisms. Finally, we enable the DTB to interact with environments by demonstrating some possible applications in vision and auditory tasks and validate the power of DTB with achieving significant correlation with the experimental counterparts.Wenlian Lu, Qibao Zheng, Ningsheng Xu, Jianfeng Feng, DTB Consortiumwork_5eedqhtevzhplhv4x53oi2bg54Tue, 29 Nov 2022 00:00:00 GMTGeneralizing Downsampling from Regular Data to Graphs
https://scholar.archive.org/work/4du632ar35ayhdnw6gswsfna5m
Downsampling produces coarsened, multi-resolution representations of data and it is used, for example, to produce lossy compression and visualization of large images, reduce computational costs, and boost deep neural representation learning. Unfortunately, due to their lack of a regular structure, there is still no consensus on how downsampling should apply to graphs and linked data. Indeed reductions in graph data are still needed for the goals described above, but reduction mechanisms do not have the same focus on preserving topological structures and properties, while allowing for resolution-tuning, as is the case in regular data downsampling. In this paper, we take a step in this direction, introducing a unifying interpretation of downsampling in regular and graph data. In particular, we define a graph coarsening mechanism which is a graph-structured counterpart of controllable equispaced coarsening mechanisms in regular data. We prove theoretical guarantees for distortion bounds on path lengths, as well as the ability to preserve key topological properties in the coarsened graphs. We leverage these concepts to define a graph pooling mechanism that we empirically assess in graph classification tasks, providing a greedy algorithm that allows efficient parallel implementation on GPUs, and showing that it compares favorably against pooling methods in literature.Davide Bacciu, Alessio Conte, Francesco Landolfiwork_4du632ar35ayhdnw6gswsfna5mMon, 28 Nov 2022 00:00:00 GMTConnecting the Dots: Floorplan Reconstruction Using Two-Level Queries
https://scholar.archive.org/work/i54di3mkprantplf4amyvuwbyq
We address 2D floorplan reconstruction from 3D scans. Existing approaches typically employ heuristically designed multi-stage pipelines. Instead, we formulate floorplan reconstruction as a single-stage structured prediction task: find a variable-size set of polygons, which in turn are variable-length sequences of ordered vertices. To solve it we develop a novel Transformer architecture that generates polygons of multiple rooms in parallel, in a holistic manner without hand-crafted intermediate stages. The model features two-level queries for polygons and corners, and includes polygon matching to make the network end-to-end trainable. Our method achieves a new state-of-the-art for two challenging datasets, Structured3D and SceneCAD, along with significantly faster inference than previous methods. Moreover, it can readily be extended to predict additional information, i.e., semantic room types and architectural elements like doors and windows. Our code and models will be available at: https://github.com/ywyue/RoomFormer.Yuanwen Yue, Theodora Kontogianni, Konrad Schindler, Francis Engelmannwork_i54di3mkprantplf4amyvuwbyqMon, 28 Nov 2022 00:00:00 GMTGeneralizations of planar contact manifolds to higher dimensions
https://scholar.archive.org/work/uhfpiu2gezcqbczcqh2vucr7eu
Iterated planar contact manifolds are a generalization of three dimensional planar contact manifolds to higher dimensions. We study some basic topological properties of iterated planar contact manifolds and discuss several examples and constructions showing that many contact manifolds are iterated planar. We also observe that for any odd integer m > 3, any finitely presented group can be realized as the fundamental group of some iterated planar contact manifold of dimension m. Moreover, we introduce another generalization of three dimensional planar contact manifolds that we call projective. Finally, building symplectic cobordisms via open books, we show that some projective contact manifolds admit explicit symplectic caps.Bahar Acu, John B. Etnyre, Burak Ozbagciwork_uhfpiu2gezcqbczcqh2vucr7euMon, 28 Nov 2022 00:00:00 GMTClosures of T-homogeneous braids are real algebraic
https://scholar.archive.org/work/nmk7ucdytbgj3b4eopsdmqomfi
A link in S^3 is called real algebraic if it is the link of an isolated singularity of a polynomial map from ℝ^4 to ℝ^2. It is known that every real algebraic link is fibered and it is conjectured that the converse is also true. We prove this conjecture for a large family of fibered links, which includes closures of T-homogeneous (and therefore also homogeneous) braids and braids that can be written as a product of the dual Garside element and a positive word in the Birman-Ko-Lee presentation. The proof offers a construction of the corresponding real polynomial maps, which can be written as semiholomorphic functions. We obtain information about their polynomial degrees.Benjamin Bodework_nmk7ucdytbgj3b4eopsdmqomfiMon, 28 Nov 2022 00:00:00 GMT2021
https://scholar.archive.org/work/ggji2kgovvhtlh6nq7bk7mukh4
Module 2 Interaction of radiation with matter -Absorption-Spontaneous emission -Stimulated emission-Einstein's coefficients (expression for energy density). Requisites of a Laser system. Condition for laser action. Principle, Construction and working of He-Ne laser. Propagation mechanism in optical fibers. Angle of acceptance. Numerical aperture. Types of optical fibers-Step index and Graded index fiber. Modes of propagation-Single mode and Multimode fibers. Attenuation-Attenuation mechanisms. Teaching Methodology: Chalk and talk method: Interaction of radiation with matter -Absorption-Spontaneous emission -Stimulated emission-Einstein's coefficients (expression for energy density). Requisites of a Laser system. Condition for laser action. Propagation mechanism in optical fibers. Angle of acceptance. Numerical aperture. Powerpoint presentation: Types of optical fibers-Step index and Graded index fiber. Modes of propagation-Single mode and Multimode fibers. Video: Construction and working of He-Ne laser. Self-study material: Attenuation-Attenuation mechanisms. 9 Hours Module 3 Temperature dependence of resistivity in metals and superconducting materials. Effect of magnetic field (Meissner effect). Isotope effect -Type I and Type II superconductors-Temperature dependence of critical field. BCS theory (qualitative). High temperature superconductors-Josephson effect -SQUID-Applications of superconductors-Maglev vehicles (qualitative). Magnetic dipole-dipole moment-flux density-magnetic field intensity-Intensity of magnetization-magnetic permeability-susceptibility-relation between permeability and susceptibility. Classification of magnetic materials-Dia, Para, Ferromagnetism. Hysteresis-soft and hard magnetic materials. Teaching Methodology: Chalk and talk method: Temperature dependence of resistivity in metals and superconducting materials. Effect of magnetic field (Meissner effect). Isotope effect -Type I and Type II superconductors-Temperature dependence of critical field. BCS theory (qualitative). High temperature superconductors-Powerpoint presentation: Josephson effect -SQUID-Applications of superconductors. Magnetic dipole-dipole moment-flux density-magnetic field intensity-Intensity of magnetization-magnetic permeability-susceptibility-relation between permeability and susceptibility. Hysteresis-soft and hard magnetic materials. Video: Maglev vehicles (qualitative). Self-study material: Classification of magnetic materials-Dia, Para, Ferromagnetism 9 Hours Module 4 Amorphous and crystalline materials-Space lattice, Bravais lattice-Unit cell, primitive cell. Lattice parameters. Crystal systems. Direction and planes in a crystal. Miller indices -Determination of Miller indices of a plane. Expression for inter -planar spacing. Atoms per unit cell -Co-ordination number. Relation between atomic radius and lattice constant -Atomic packing factors (SC, FCC, BCC). Bragg's law. Determination of crystal structure using Bragg's X-ray diffractometer -X-ray spectrum. Teaching Methodology: Chalk and talk method: Direction and planes in a crystal. Miller indices -Determination of Miller indices of a plane. Powerpoint presentation: Atoms per unit cell -Co-ordination number. Relation between atomic radius and lattice constant -Atomic packing factors (SC, FCC, BCC). Bragg's law. Determination of crystal structure using Bragg's X-ray diffractometer -X-ray spectrum. Self-study material: Amorphous and crystalline materials-Space lattice, Bravais lattice-Unit cell, primitive cell. Lattice parameters. Crystal systems. 9 Hours Module 5 Interference of light -Superposition of two coherent waves-Constructive and destructive interference. Interference in thin films -Wedge shaped thin film-Air wedge -Application to find the diameter of a thin wire. Newton's rings -Application to find the refractive index of a liquid. Diffraction of light -Classes of diffraction -Fresnel and Fraunhofer diffraction. Fresnel theory of half period zone -Zone plate. Diffraction grating -Grating element -Grating equation -Construction of grating-Reflection and transmission grating. Teaching Methodology: Chalk and talk method: Interference of light -Superposition of two coherent waves-Constructive and destructive interference. Powerpoint presentation: Interference in thin films -Wedge shaped thin film-Air wedge -Application to find the diameter of a thin wire. Newton's rings -Application to find the refractive index of a liquid. Fresnel theory of half period zone -Zone plate. Diffraction grating -Grating element -Grating equation -Construction of grating-Reflection and transmission grating. Self-study material: Diffraction of light -Classes of diffraction -Fresnel and Fraunhofer diffraction. 9 Hours C PROGRAMMING Subject Code 21SCS12 IA Marks 50 Number of Lecture Hours/Week 2 (L) + 2 (T) Exam Marks 50 Total Number of Lecture Hours 45 Total Marks 100 Credits 03 Exam Hours 2 Course Objectives: 1. To understand the various steps in program development. 2. To learn the syntax and semantics of C programming language. 3. To learn the usage of structured programming approach in solving problems. Course Outcomes: CO1: On completion of this course students will be able to write algorithms and to draw flowcharts for solving problems. CO2: On completion of this course students will be able to convert the algorithms/flowcharts to C programs. CO3: Students will be able to code and test a given logic in C programming language. CO4: Students will be able to decompose a problem into functions and to develop modular reusable code. CO5: Students will be able to use arrays, pointers, strings and structures to write C programs. Module 1 Introduction to Algorithms: Steps to solve logical and numerical problems. Representation of Algorithm, Flowchart/Pseudo code with examples, Program design and structured programming Introduction to C Programming Language: variables, Syntax and Logical Errors in compilation, object and executable code, Operators, expressions and precedence, Expression evaluation, Storage classes, type conversion, The main method and command line arguments. Bitwise operations: Bitwise AND, OR, XOR and NOT operators. Conditional Branching and Loops: Writing and evaluation of conditionals and consequent branching with if, if-else, switch-case, ternary operator, goto, Iteration with for, while, do-while loops I/O: Simple input and output with scanf and printf, formatted I/O, Introduction to stdin, stdout and stderr. Command line arguments. Teaching Methodology: Chalk and talk using PPT and Demo to explain the concept. 9 Hours Module 2 Arrays, Strings, Structures and Pointers: Arrays: one and two-dimensional arrays, creating, accessing and manipulating elements of arrays. Strings: Introduction to strings, handling strings as array of characters, basic string functions available in C (strlen, strcat, strcpy, strstr etc.), arrays of strings. Structures: Defining structures, initializing structures, unions, Array of structures. Pointers: Idea of pointers, Defining pointers, Pointers to Arrays and Structures, Use of Pointers in self referential structures, usage of self referential structures in linked list (no implementation) Enumeration data type. Teaching Methodology: Chalk and talk using PPT and Demo to explain the concept. Module 3 9 Hours Preprocessor and File handling in C: Preprocessor: Commonly used Preprocessor commands like include, define, undef, if, ifdef, ifndef Files: Text and Binary files, Creating and Reading and writing text and binary files, Appending data to existing files, Writing and reading structures using binary files, Random access using fseek, ftell and rewind functions. Teaching Methodology: Chalk and talk using PPT and Demo to explain the concept. 9 Hours Module 4 Function and Dynamic Memory Allocation: Functions: Designing structured programs, Declaring a function, Signature of a function, Parameters and return type of a function, passing parameters to functions, call by value, Passing arrays to functions, passing pointers to functions, idea of call by reference, Some C standard functions and libraries Recursion: Simple programs, such as Finding Factorial, Fibonacci series etc., Limitations of Recursive functions. Dynamic memory allocation: Allocating and freeing memory, Allocating memory for arrays of different data types. Teaching Methodology: Chalk and talk using PPT and Demo to explain the concept. 9 Hours Module 5 C PROGRAMMING LABORATORY Subject Code 21SCSL12 IA Marks 25 Number of Practical Hours/Week 1 (T) + 2 (L) Exam Marks 25 Total Number of Practical Hours 36 Total Marks 50 Credits 02 Exam Hours 3 Course Objectives: 1. To describe the basics of computer and understand the problem-solving aspect. 2. To demonstrate the algorithm and flow chart for the given problem. 3. To introduce students to the basic knowledge of programming fundamentals of C language. 4. To impart writing skill of C programming to the students and solving problems. 5. To impart the concepts like looping, array, functions, pointers, file, structure. Course Outcomes: CO1: Understand the problem solving to write efficient algorithms to solve real time problems. CO2: Understand and use various constructs of the programming language such as conditionals, iteration, and recursion. CO3: Implement your algorithms to build programs in the C programming language. CO4: Use data structures like arrays, linked lists, and stacks to solve various problems. CO5: Understand and use file handling in the C programming language. EXPERIMENTS: Implement the following programs with WINDOWS / LINUX platform using appropriate C compiler. Course Objectives: 1. To provide basic concepts D.C circuits and circuit analysis techniques 2. To provide knowledge on A.C circuit fundamental techniques 3. To understand construction and operation of BJT and Junction FET 4. Explain the different modes of communications from wired to wireless and the computing involved. 5. To provide fundamental knowledge of Digital Logic. Course Outcomes: CO1: Understand concepts of electrical circuits and elements. CO2: Apply basic electric laws in solving circuit problems. CO3: Analyze simple circuits containing transistors CO4: Understand concept of cellular wireless networks. CO5: Understand Number systems and design basic digital circuits.BTECH.MECHwork_ggji2kgovvhtlh6nq7bk7mukh4Mon, 28 Nov 2022 00:00:00 GMTBoundary Graph Neural Networks for 3D Simulations
https://scholar.archive.org/work/nf2n4z4rhfajrimbxvt2faa52u
The abundance of data has given machine learning considerable momentum in natural sciences and engineering, though modeling of physical processes is often difficult. A particularly tough problem is the efficient representation of geometric boundaries. Triangularized geometric boundaries are well understood and ubiquitous in engineering applications. However, it is notoriously difficult to integrate them into machine learning approaches due to their heterogeneity with respect to size and orientation. In this work, we introduce an effective theory to model particle-boundary interactions, which leads to our new Boundary Graph Neural Networks (BGNNs) that dynamically modify graph structures to obey boundary conditions. The new BGNNs are tested on complex 3D granular flow processes of hoppers, rotating drums and mixers, which are all standard components of modern industrial machinery but still have complicated geometry. BGNNs are evaluated in terms of computational efficiency as well as prediction accuracy of particle flows and mixing entropies. BGNNs are able to accurately reproduce 3D granular flows within simulation uncertainties over hundreds of thousands of simulation timesteps. Most notably, in our experiments, particles stay within the geometric objects without using handcrafted conditions or restrictions.Andreas Mayr, Sebastian Lehner, Arno Mayrhofer, Christoph Kloss, Sepp Hochreiter, Johannes Brandstetterwork_nf2n4z4rhfajrimbxvt2faa52uMon, 28 Nov 2022 00:00:00 GMT