Patterns in Nature
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Glossary Physics (I-Introduction)
1 Glossary Physics (I-introduction) - Efficiency: The percent of the work put into a machine that is converted into useful work output; = work done / energy used [-]. = eta In machines: The work output of any machine cannot exceed the work input (<=100%); in an ideal machine, where no energy is transformed into heat: work(input) = work(output), =100%. Energy: The property of a system that enables it to do work. Conservation o. E.: Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes. Equilibrium: The state of an object when not acted upon by a net force or net torque; an object in equilibrium may be at rest or moving at uniform velocity - not accelerating. Mechanical E.: The state of an object or system of objects for which any impressed forces cancels to zero and no acceleration occurs. Dynamic E.: Object is moving without experiencing acceleration. Static E.: Object is at rest.F Force: The influence that can cause an object to be accelerated or retarded; is always in the direction of the net force, hence a vector quantity; the four elementary forces are: Electromagnetic F.: Is an attraction or repulsion G, gravit. const.6.672E-11[Nm2/kg2] between electric charges: d, distance [m] 2 2 2 2 F = 1/(40) (q1q2/d ) [(CC/m )(Nm /C )] = [N] m,M, mass [kg] Gravitational F.: Is a mutual attraction between all masses: q, charge [As] [C] 2 2 2 2 F = GmM/d [Nm /kg kg 1/m ] = [N] 0, dielectric constant Strong F.: (nuclear force) Acts within the nuclei of atoms: 8.854E-12 [C2/Nm2] [F/m] 2 2 2 2 2 F = 1/(40) (e /d ) [(CC/m )(Nm /C )] = [N] , 3.14 [-] Weak F.: Manifests itself in special reactions among elementary e, 1.60210 E-19 [As] [C] particles, such as the reaction that occur in radioactive decay. -
Title: Fractals Topics: Symmetry, Patterns in Nature, Biomimicry Related Disciplines: Mathematics, Biology Objectives: A. Learn
Title: Fractals Topics: symmetry, patterns in nature, biomimicry Related Disciplines: mathematics, biology Objectives: A. Learn about how fractals are made. B. Think about the mathematical processes that play out in nature. C. Create a hands-on art project. Lesson: A. Introduction (20 minutes) Fractals are sets in mathematics based on repeated processes at different scales. Why do we care? Fractals are a part of nature, geometry, algebra, and science and are beautiful in their complexity. Fractals come in many types: branching, spiral, algebraic, and geometric. Branching and spiral fractals can be found in nature in many different forms. Branching is seen in trees, lungs, snowflakes, lightning, and rivers. Spirals are visible in natural forms such as hurricanes, shells, liquid motion, galaxies, and most easily visible in plants like flowers, cacti, and Romanesco Figure 1: Romanesco (Figure 1). Branching fractals emerge in a linear fashion. Spirals begin at a point and expand out in a circular motion. A cool demonstration of branching fractals can be found at: http://fractalfoundation.org/resources/what-are-fractals/. Algebraic fractals are based on surprisingly simple equations. Most famous of these equations is the Mandelbrot Set (Figure 2), a plot made from the equation: The most famous of the geometric fractals is the Sierpinski Triangle: As seen in the diagram above, this complex fractal is created by starting with a single triangle, then forming another inside one quarter the size, then three more, each one quarter the size, then 9, 27, 81, all just one quarter the size of the triangle drawn in the previous step. -
Test of Self-Organization in Beach Cusp Formation Giovanni Coco,1 T
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 108, NO. C3, 3101, doi:10.1029/2002JC001496, 2003 Test of self-organization in beach cusp formation Giovanni Coco,1 T. K. Burnet, and B. T. Werner Complex Systems Laboratory, Cecil and Ida Green Institute of Geophysics and Planetary Physics, University of California, San Diego, La Jolla, California, USA Steve Elgar Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA Received 4 June 2002; revised 6 November 2002; accepted 13 November 2002; published 29 March 2003. [1] Field observations of swash flow patterns and morphology change are consistent with the hypothesis that beach cusps form by self-organization, wherein positive feedback between swash flow and developing morphology causes initial development of the pattern and negative feedback owing to circulation of flow within beach cusp bays causes pattern stabilization. The self-organization hypothesis is tested using measurements from three experiments on a barrier island beach in North Carolina. Beach cusps developed after the beach was smoothed by a storm and after existing beach cusps were smoothed by a bulldozer. Swash front motions were recorded on video during daylight hours, and morphology was measured by surveying at 3–4 hour intervals. Three signatures of self- organization were observed in all experiments. First, time lags between swash front motions in beach cusp bays and horns increase with increasing relief, representing the effect of morphology on flow. Second, differential erosion between bays and horns initially increases with increasing time lag, representing the effect of flow on morphology change because positive feedback causes growth of beach cusps. Third, after initial growth, differential erosion decreases with increasing time lag, representing the onset of negative feedback that stabilizes beach cusps. -
Quartz Crystal Division of Seiko Instruments Inc
(1) Quartz Crystal Division of Seiko Instruments Inc. and affiliates, which is responsible for manufacturing the products described in this catalogue, holds ISO 9001 and ISO 14001 certification. (2) SII Crystal Technology Inc. Tochigi site holds IATF 16949 certification. Quartz Crystal Product Catalogue Electronic Components Sales Head Office 1-8, Nakase, Mihamaku, Chiba-shi, Chiba 261-8507, Japan Telephone:+81-43-211-1207 Facsimile:+81-43-211-8030 E-mail:[email protected] <Manufacturer> SII Crystal Technology Inc. 1110, Hirai-cho, Tochigi-shi, Tochigi 328-0054, Japan Released in February 2019 No.QTC2019EJ-02C1604 Creating Time - Optimizing Time - Enriching Time Seiko Instruments Inc. (SII), founded in 1937 as a member of the Seiko Group specializing in the manufacture of watches, has leveraged its core competency in high precision watches to create a wide range of new products and technologies. Over the years SII has developed high-precision processed parts and machine tools that pride themselves on their sub-micron processing capability, quartz crystals that came about as a result of our quartz watch R&D, and electronic components such as micro batteries. Optimizing our extensive experience and expertise, we have since diversified into such new fields as compact, lightweight, exceedingly quiet thermal printers, and inkjet printheads, a key component in wide format inkjet printers for corporate use. SII, in the years to come, will maintain an uncompromised dedication to its time-honored technologies and innovations of craftsmanship, miniaturization, and efficiency that meet the needs of our changing society and enrich the lives of those around us. SEIKO HOLDINGS GROUP 1881 1917 1983 1997 2007 K. -
WHAT IS...A Quasicrystal?, Volume 53, Number 8
?WHAT IS... a Quasicrystal? Marjorie Senechal The long answer is: no one is sure. But the short an- diagrams? The set of vertices of a Penrose tiling does— swer is straightforward: a quasicrystal is a crystal that was known before Shechtman’s discovery. But with forbidden symmetry. Forbidden, that is, by “The what other objects do, and how can we tell? The ques- Crystallographic Restriction”, a theorem that confines tion was wide open at that time, and I thought it un- the rotational symmetries of translation lattices in two- wise to replace one inadequate definition (the lattice) and three-dimensional Euclidean space to orders 2, 3, with another. That the commission still retains this 4, and 6. This bedrock of theoretical solid-state sci- definition today suggests the difficulty of the ques- ence—the impossibility of five-fold symmetry in crys- tion we deliberately but implicitly posed. By now a tals can be traced, in the mineralogical literature, back great many kinds of aperiodic crystals have been to 1801—crumbled in 1984 when Dany Shechtman, a grown in laboratories around the world; most of them materials scientist working at what is now the National are metals, alloys of two or three kinds of atoms—bi- Institute of Standards and Technology, synthesized nary or ternary metallic phases. None of their struc- aluminium-manganese crystals with icosahedral sym- tures has been “solved”. (For a survey of current re- metry. The term “quasicrystal”, hastily coined to label search on real aperiodic crystals see, for example, the such theretofore unthinkable objects, suggests the website of the international conference ICQ9, confusions that Shechtman’s discovery sowed. -
Claus Kahlert and Otto E. Rössler Institute for Physical and Theoretical Chemistry, University of Tübingen Z. Naturforsch
Chaos as a Limit in a Boundary Value Problem Claus Kahlert and Otto E. Rössler Institute for Physical and Theoretical Chemistry, University of Tübingen Z. Naturforsch. 39a, 1200- 1203 (1984); received November 8, 1984 A piecewise-linear. 3-variable autonomous O.D.E. of C° type, known to describe constant- shape travelling waves in one-dimensional reaction-diffusion media of Rinzel-Keller type, is numerically shown to possess a chaotic attractor in state space. An analytical method proving the possibility of chaos is outlined and a set of parameters yielding Shil'nikov chaos indicated. A symbolic dynamics technique can be used to show how the limiting chaos dominates the behavior even of the finite boundary value problem. Reaction-diffusion equations occur in many dis boundary conditions are assumed. This result was ciplines [1, 2], Piecewise-linear systems are especially obtained by an analytical matching method. The amenable to analysis. A variant to the Rinzel-Keller connection to chaos theory (Smale [6] basic sets) equation of nerve conduction [3] can be written as was not evident at the time. In the following, even the possibility of manifest chaos will be demon 9 ö2 — u u + p [- u + r - ß + e (ii - Ö)], strated. o t oa~ In Fig. 1, a chaotic attractor of (2) is presented. Ö The flow can be classified as an example of "screw- — r = - e u + r , (1) 0/ type-chaos" (cf. [7]). A second example of a chaotic attractor is shown in Fig. 2. A 1-D projection of a where 0(a) =1 if a > 0 and zero otherwise; d is the 2-D cross section through the chaotic flow in a threshold parameter. -
Bubble Raft Model for a Paraboloidal Crystal
Syracuse University SURFACE Physics College of Arts and Sciences 9-17-2007 Bubble Raft Model for a Paraboloidal Crystal Mark Bowick Department of Physics, Syracuse University, Syracuse, NY Luca Giomi Syracuse University Homin Shin Syracuse University Creighton K. Thomas Syracuse University Follow this and additional works at: https://surface.syr.edu/phy Part of the Physics Commons Recommended Citation Bowick, Mark; Giomi, Luca; Shin, Homin; and Thomas, Creighton K., "Bubble Raft Model for a Paraboloidal Crystal" (2007). Physics. 144. https://surface.syr.edu/phy/144 This Article is brought to you for free and open access by the College of Arts and Sciences at SURFACE. It has been accepted for inclusion in Physics by an authorized administrator of SURFACE. For more information, please contact [email protected]. Bubble Raft Model for a Paraboloidal Crystal Mark J. Bowick, Luca Giomi, Homin Shin, and Creighton K. Thomas Department of Physics, Syracuse University, Syracuse New York, 13244-1130 We investigate crystalline order on a two-dimensional paraboloid of revolution by assembling a single layer of millimeter-sized soap bubbles on the surface of a rotating liquid, thus extending the classic work of Bragg and Nye on planar soap bubble rafts. Topological constraints require crystalline configurations to contain a certain minimum number of topological defects such as disclinations or grain boundary scars whose structure is analyzed as a function of the aspect ratio of the paraboloid. We find the defect structure to agree with theoretical predictions and propose a mechanism for scar nucleation in the presence of large Gaussian curvature. Soft materials such as amphiphilic membranes, diblock any triangulation of M reads copolymers and colloidal emulsions can form ordered structures with a wide range of complex geometries and Q = X(6 ci)+ X (4 ci)=6χ , (1) − − topologies. -
Crystal Structures and Symmetry 1 Crystal Structures and Symmetry
PHYS 624: Crystal Structures and Symmetry 1 Crystal Structures and Symmetry Introduction to Solid State Physics http://www.physics.udel.edu/∼bnikolic/teaching/phys624/phys624.html PHYS 624: Crystal Structures and Symmetry 2 Translational Invariance • The translationally invariant nature of the periodic solid and the fact that the core electrons are very tightly bound at each site (so we may ignore their dynamics) makes approximate solutions to many-body problem ≈ 1021 atoms/cm3 (essentially, a thermodynamic limit) possible. Figure 1: The simplest model of a solid is a periodic array of valance orbitals embedded in a matrix of atomic cores. Solving the problem in one of the irreducible elements of the periodic solid (e.g., one of the spheres in the Figure), is often equivalent to solving the whole system. PHYS 624: Crystal Structures and Symmetry 3 From atomic orbitals to solid-state bands • If two orbitals are far apart, each orbital has a Hamiltonian H0 = εn, where n is the orbital occupancy ⇐ Ignoring the effects of electronic corre- lations (which would contribute terms proportional to n↑n↓). + +++ ... = Band E Figure 2: If we bring many orbitals into proximity so that they may exchange electrons (hybridize), then a band is formed centered around the location of the isolated orbital, and with width proportional to the strength of the hybridization PHYS 624: Crystal Structures and Symmetry 4 From atomic orbitals to solid-state bands • Real Life: Solids are composed of elements with multiple orbitals that produce multiple bonds. Now imagine what happens if we have several orbitals on each site (ie s,p, etc.), as we reduce the separation between the orbitals and increase their overlap, these bonds increase in width and may eventually overlap, forming bands. -
Crystal Symmetry Groups
X-Ray and Neutron Crystallography rational numbers is a group under Crystal Symmetry Groups multiplication, and both it and the integer group already discussed are examples of infinite groups because they each contain an infinite number of elements. ymmetry plays an important role between the integers obey the rules of In the case of a symmetry group, in crystallography. The ways in group theory: an element is the operation needed to which atoms and molecules are ● There must be defined a procedure for produce one object from another. For arrangeds within a unit cell and unit cells example, a mirror operation takes an combining two elements of the group repeat within a crystal are governed by to form a third. For the integers one object in one location and produces symmetry rules. In ordinary life our can choose the addition operation so another of the opposite hand located first perception of symmetry is what that a + b = c is the operation to be such that the mirror doing the operation is known as mirror symmetry. Our performed and u, b, and c are always is equidistant between them (Fig. 1). bodies have, to a good approximation, elements of the group. These manipulations are usually called mirror symmetry in which our right side ● There exists an element of the group, symmetry operations. They are com- is matched by our left as if a mirror called the identity element and de- bined by applying them to an object se- passed along the central axis of our noted f, that combines with any other bodies. -
Chapter 16: Fourier Series
Chapter 16: Fourier Series 16.1 Fourier Series Analysis: An Overview A periodic function can be represented by an infinite sum of sine and cosine functions that are harmonically related: Ϧ ͚ʚͨʛ Ɣ ͕1 ƍ ȕ ͕) cos ͢!*ͨ ƍ ͖) sin ͢!*ͨ Fourier Coefficients: are)Ͱͥ calculated from ͕1; ͕); ͖) ͚ʚͨʛ Fundamental Frequency: ͦ_ where multiples of this frequency are called !* Ɣ ; ͢! * harmonic frequencies Conditions that ensure that f(t) can be expressed as a convergent Fourier series: (Dirichlet’s conditions) 1. f(t) be single-values 2. f(t) have a finite number of discontinuities in the periodic interval 3. f(t) have a finite number of maxima and minima in the periodic interval 4. the integral /tͮ exists Ȅ/ |͚ʚͨʛ|ͨ͘; t These are sufficient conditions not necessary conditions; therefore if these conditions exist the functions can be expressed as a Fourier series. However if the conditions are not met the function may still be expressible as a Fourier series. 16.2 The Fourier Coefficients Defining the Fourier coefficients: /tͮ 1 ͕1 Ɣ ǹ ͚ʚͨʛͨ͘ ͎ /t /tͮ 2 ͕& Ɣ ǹ ͚ʚͨʛ cos ͟!*ͨ ͨ͘ ͎ /t /tͮ 2 ͖& Ɣ ǹ ͚ʚͨʛ sin ͟!*ͨ ͨ͘ ͎ / t Example 16.1 Find the Fourier series for the periodic waveform shown. Assessment problems 16.1 & 16.2 ECEN 2633 Spring 2011 Page 1 of 5 16.3 The Effects of Symmetry on the Fourier Coefficients Four types of symmetry used to simplify Fourier analysis 1. Even-function symmetry 2. Odd-function symmetry 3. -
Branching in Nature Jennifer Welborn Amherst Regional Middle School, [email protected]
University of Massachusetts Amherst ScholarWorks@UMass Amherst Patterns Around Us STEM Education Institute 2017 Branching in Nature Jennifer Welborn Amherst Regional Middle School, [email protected] Wayne Kermenski Hawlemont Regional School, [email protected] Follow this and additional works at: https://scholarworks.umass.edu/stem_patterns Part of the Biology Commons, Physics Commons, Science and Mathematics Education Commons, and the Teacher Education and Professional Development Commons Welborn, Jennifer and Kermenski, Wayne, "Branching in Nature" (2017). Patterns Around Us. 2. Retrieved from https://scholarworks.umass.edu/stem_patterns/2 This Article is brought to you for free and open access by the STEM Education Institute at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Patterns Around Us by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Patterns Around Us: Branching in Nature Teacher Resource Page Part A: Introduction to Branching Massachusetts Frameworks Alignment—The Nature of Science • Overall, the key criterion of science is that it provide a clear, rational, and succinct account of a pattern in nature. This account must be based on data gathering and analysis and other evidence obtained through direct observations or experiments, reflect inferences that are broadly shared and communicated, and be accompanied by a model that offers a naturalistic explanation expressed in conceptual, mathematical, and/or mechanical terms. Materials: -
Coating Provides Infrared Camouflage
COURTESY OF PATRICK RONEY, ALIREZA SHAHSAFI AND MIKHAIL KATS February 1, 2020 Coating Provides Infrared Camouflage February 1, 2020 Coating Provides Infrared Camouflage About this Guide This Guide, based on the Science News article “Coating provides infrared camouflage,” asks students to explore the physics and potential technological applications of a material, discuss the various types of electromagnetic radiation, analyze infrared images and research how infrared imaging is used across a range of fields. This Guide includes: Article-based Comprehension Q&A — These questions, based on the Science News article “Coating provides infrared camouflage,” Readability: 12.7, ask students to explore the physics and potential technological applications of a material. Related standards include NGSS-DCI: HS-PS4; HS-PS3; HS-PS2; HS-ETS1. Student Comprehension Worksheet — These questions are formatted so it’s easy to print them out as a worksheet. Cross-curricular Discussion Q&A — Students will watch a NASA video about the electromagnetic spectrum to learn about properties of the various types of radiation. Then, students will explore and discuss technologies that use specific types of electromagnetic radiation. Related standards include NGSS- DCI: HS-PS4; HS-PS3; HS-PS2. Student Discussion Worksheet — These questions are formatted so it’s easy to print them out as a worksheet. Activity: Seeing in Infrared Summary: In this activity, students will analyze infrared images and then explore how infrared imaging is used across a range of fields of work. Skills include researching, evaluating, synthesizing and presenting information. Related standards include NGSS-DCI: HS-PS4; HS-PS3; HS-ETS1. Approximate class time: 1 class period to complete the discussion, research, presentations and debriefing as a class.