Found 7 PDF associated with tag : Academic
Is the Internet for Porn? An Insight Into the Online Adult Industry Gilbert Wondracek1 , Thorsten Holz1 , Christian Platzer1 , Engin Kirda2 , and Christopher Kruegel3 Secure Systems Lab, Technical University Vienna Abstract University of California, Santa Barbara Apparently, even roughly estimating the size of the Internet porn industry is non-trivial, as different sources [2, 10, 28] indicate a yearly total revenue that ranges from 1 to 97 billion USD. Yet, even the lowest of these estimates hints at the economic signiﬁcance of this market. Interestingly, however, to the best of our knowledge, no study has yet been published that analyzes the economical and technological structure of this industry from a security point of view. In this work, we aim at answering the following questions: Which economic roles exist in the online adult industry? Our analysis shows that there is a broad array of economic roles that web sites in this industry can assume. Apart from the purpose of selling pornographic media over the Internet, there are much less obvious and visible business models in this industry, such as trafﬁc trading web sites or cliques of business competitors who cooperate to increase their revenue. We identify, in this paper, the main economic roles of the adult industry and show the associated revenue models, organizational structures, technical features and interdependencies with other economic actors.
Physics 251.3: Relativistic Mechanics and Quantum Physics Box approximations for quantum wells, quantum wires and quantum dots A particle in three dimensions which can move freely in two directions, but is conﬁned in one direction, is said to be conﬁned in a quantum well. A particle which can move freely only in one direction but is conﬁned in two directions is conﬁned in a quantum wire. Finally, a particle which is conﬁned to a small region of space is conﬁned to a quantum dot. We will discuss energy levels and wavefunctions of particles in all three situations in the approximation of conﬁnement to rectangular (box-like) regions. For the quantum well this means that our particle will be conﬁned to the region 0 < x < L1 , but it can move freely in y and z direction. The particle in the quantum wire is conﬁned in x and y direction to 0 < x < L1 , 0 < y < L2 , but it can move freely in the z direction. Finally, box approximation for a quantum dot means that the particle is conﬁned to the box 0 < x < L1 , 0 < y < L2 , 0 < z < L3 . In the allowed regions, the particle will not feel a potential, U(x) = 0, i.e. in the allowed regions
Mesoscopic Fractional Quantum in Soft Matter W. Chen Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Division Box 26, Beijing 100088, P. R. China (firstname.lastname@example.org) Abstract. - Soft matter (e.g., biomaterials, polymers, sediments, oil, emulsions) has become an important bridge between physics and diverse disciplines. Its fundamental physical mechanism, however, is largely obscure. This study made the first attempt to connect fractional Schrodinger equation and soft matter physics under a consistent framework from empirical power scaling to phenomenological kinetics and macromechanics to mesoscopic quantum mechanics. The original contributions are the fractional quantum relationships, which show Lévy statistics and fractional Brownian motion are essentially related to momentum and energy, respectively. The fractional quantum underlies fractal mesostructures and many-body interactions of macromolecules in soft matter and is experimentally testable. The frequency scaling power law of fractional order appears universal in physical behaviors of soft matter (1-5) and is considered “anomalous” compared with those of the ideal solids and fluids. For instance, Jonscher (4) concluded that a fractional frequency power law was “the universal dielectric response” in soft matter. It is also well-known (5, 6) that acoustic wave propagation through soft matters (Fig. 1, reproduced from Ref. 5) obeys frequency power law dissipation. The standard mathematical modeling approach using integer-order time-space derivatives can not accurately reflect fractional frequency power law, while the fractional derivatives are instead found an irreplaceable modeling approach. In particular, anomalous diffusion equation has been recognized as a master
Topics covered Basic concepts of quantum physics Particles as waves and waves as particles Wave packets Uncertainty principle and Fourier transform Wave function of a quantum particle Probability interpretation, superposition, entanglement, qubits Schrödinger equation Time-independent Schrödinger equation, stationary states Free particle, infinite square well (1D-3D) Numerical (finite-difference) solution of the time-independent Schrödinger equation Potential barriers, tunneling Harmonic and anharmonic oscillator Semiconductor crystal structure, Miller indices for cubic crystals Photonic analogues: photonic crystals Electronic wave functions and band structure of solids Quasiparticles in solids Effective mass, density of states Thermal energy distribution: Fermi-Dirac and Maxwell-Boltzmann Band diagrams and operation of common electronic devices Semiconductor quantum wells (square and triangular) Examples of carriers in semiconductor quantum wells: Quantum well laser Two-dimensional electron gas (2DEG) in HEMTs and MOSFETs Single electron transistor (SET) Quantum Hall effect Quantum wire and quantum dot structures Superconductivity Superconducting electronics : Josephson Junction, SQUID Spintronics Molecular Electronics
Physics Orientation PHYS 1000 Physics: Purpose and Practice Observation Measurement Synthesis Verification Generalization Experiment and Theory Experimental Method Development of Theory Experimental-Theory Interaction Areas of Classical Physics Mechanics Electromagnetism Statistical Mechanics Optics Areas of Modern Physics Special Relativity – General Relativity Quantum Mechanics – Field Theory Atomic Physics Condensed Matter Physics Quantum Optics – Laser Physics Nuclear Physics – Elementary Particle Physics Nonlinear Dynamics and Chaos Astrophysics – Cosmology Physics and Society Research – Development – Implementation Transportation Energy Environment
The Paradoxes of Quantum Mechanics1 The early successes of physics, starting with the work of Galileo, Kepler and Newton, and continuing up to the beginning of the twentieth century, dealt primarily with things that were at least large enough to see and handle. This is the world of our intuition and common sense. Everyone who has learned to play billiards, for example, knows instinctively the Newtonian concepts of force, impulse, momentum, and energy. He or she may not be able to express these ideas mathematically, but in fact the equations only express in a quantitative mathematical way those things that every billiard player knows intuitively and physiologically. The physics of things that are very small, on the other hand, such as atoms, molecules and elementary particles, was developed more recently starting with the work of Niels Bohr, Erwin Schrodinger, Werner Heisenberg and others during the 1920’s. We call this body of theory quantum mechanics; and by now it has been veriﬁed in so many ways that its validity is virtually beyond question. At least as a paradigm for doing precise numerical calculations that can be tested experimentally, quantum mechanics is as accurate and unambiguous as any man made theory is ever likely to be. There is no controversy about this; but when we ask just what this theory is telling us about the ultimate nature of reality, the answers are so strange and counterintuitive that physicists have been arguing about them without any consensus ever since the ﬁrst principles were formulated almost eighty years ago.
PH3410 is the first course in a year-long sequence devoted to the study of elementary quantum mechanics. The course begins with a review of the properties of particles, waves and probability distributions. Quantum theory is then introduced through the investigation of the discoveries and ideas of the early twentieth century that culminated in the development of quantum mechanics. These discoveries and ideas include particle-like properties of radiation, the “old” quantum theory of Bohr, wave-like properties of matter and Schrödinger’s wave equation. Schrödinger’s equations will be used to study the infinite square well, the harmonic oscillator, and the potential step and barrier. When topics of interest are governed by either partial differential equations or unfamiliar ordinary differential equations, the necessary mathematics will be developed. Course Objectives The principal course objectives are for you to build a solid base in quantum mechanics by learning the fundamental concepts of the subject and developing the problem-solving skills needed to apply those fundamentals. The objectives are not properly served by a mere survey of factual information; the course will have sufficient depth to explicate the basic concepts. A worthy secondary objective of the course is to strengthen your analytical abilities with exposure to new mathematics.
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