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6.006 Introduction to Algorithms, Fall 2011 by Massachusetts Institute of Technology, 6.006 course staff Lecture 10: Hashing III: Open Addressing by
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Unsigned lecture notes issued by the Massachusetts Institute of Technology and hosted by MIT OpenCourseWare. Fall 2011 dates the course offering; no PDF publication or revision date or individual author byline is established.
6.006 Introduction to Algorithms, Fall 2011 by Massachusetts Institute of Technology, 6.006 course staff Lecture 17: Shortest Paths III: Bellman-Ford by
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Lecture notes in 6.006 Introduction to Algorithms, Fall 2011 by Massachusetts Institute of Technology, 6.006 course staff. Massachusetts Institute of Technology issues the notes; MIT OpenCourseWare hosts them. No individual note-author byline is established. Fall 2011 dates the course offering; no separate PDF publication or revision date is verified.
Chapter 15 in 18.03 Supplementary Notes by Haynes Miller. Authorship inherits the explicitly verified collection credit to Haynes Miller; it is not inferred from course instructor credits. No separate chapter publication date is verified.
Supplementary course notes issued by Massachusetts Institute of Technology and hosted by MIT OpenCourseWare. No individual note author is independently verified. The final-page course imprint gives Fall 2010; this identifies the course term.
Wave propagation is the evolution of a disturbance through space and time under the medium's dynamical equations. In a uniform nondispersive one-dimensional model,the wave equation admits rightward and leftward profiles . Each profile travels at wave speed without changing shape, so a measured delay over a known distance can determine .
A real medium can alter this simple picture through dispersion, wave absorption, wave reflection and wave scattering. Phase velocity follows a fixed wave phase, while group velocity describes a narrowband wave packet's envelope in a regime where that approximation holds. Neither should be identified automatically with every signal's arrival speed. Specifying an initial disturbance and suitable boundary conditions determines which of the possible propagation patterns occurs.
Wave reflection returns part of an incident wave into the medium from which it arrived, as a consequence of an interface or spatial variation of material properties. An amplitude reflection coefficient compares the reflected and incident waves; its squared modulus gives their wave intensity ratio when both use the same medium and normalization. Reflected energy has not necessarily undergone wave absorption.
A chirp is an oscillation whose instantaneous frequency changes with time. For , with a smoothly increasing wave phase , the instantaneous frequency is . A linear chirp hasThe chirp rate has units of hertz per second; positive and negative values give increasing and decreasing frequency over intervals where the stated interpretation applies.
A swept tone can probe the response of a coupled oscillator over a band, although a rapid sweep need not reproduce the steady response at each frequency. In radar or sonar, comparing a returned chirp with the transmitted signal supports pulse compression: a long transmitted signal can be processed into a narrow delay peak. A finite-duration chirp occupies a range of frequencies, even though its local wave phase supplies a well-defined instantaneous rate.
A waveguide confines a wave transversely while allowing propagation along a longitudinal direction. Material properties and boundary conditions select transverse normal modes, whose longitudinal dispersion relations may have cutoffs even when the bulk material is nondispersive. Examples include an optical fiber, a hollow electromagnetic waveguide, and a membrane waveguide. Guiding reduces geometric spreading along the chosen route but does not eliminate absorption, scattering or leakage.
A bacteriophage is a virus that infects bacteria. The Luria-Delbrück experiment uses a bacteriophage challenge to reveal resistant biological colonies.
The characteristic impedance is the voltage-to-current ratio of a single forward travelling wave on a uniform transmission line. For real and a real load resistance , the voltage-wave reflection coefficient is and the power accepted by the load is the incident power times .
A distributed transmission line with per-unit-length series resistance , series inductance , shunt conductance and shunt capacitance obeys the displayed coupled first-order equations by applying Kirchhoff's voltage law and Kirchhoff's current law to a short element. With , both voltage and current satisfy a wave equation with speed and characteristic impedance . The quantities are distributed parameters, not a single lumped resistor or capacitor.
Two perfectly conducting wide strips of width and separation , filled with a homogeneous nonmagnetic dielectric of absolute permittivity , support a transverse electromagnetic mode. Ignoring edge fields, their distributed capacitance is and distributed external inductance is . The magnetic-energy integral gives the latter. Their characteristic impedance is and propagation speed is . These parameters are per unit length, distinct from a lumped capacitor and inductor.
On a uniform lossless transmission line, incident and reflected sinusoidal waves give voltage maxima and minima . Their ratio is the voltage standing wave ratio, , where is the voltage-wave reflection coefficient. A matched termination gives one, while perfect reflection gives an infinite ratio. These expressions assume a common real characteristic impedance and no propagation attenuation between the compared extrema.
Magnetizing reactance and reflected resistance in a transformer by
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For an ideal electrical transformer with turns ratio , the secondary load appears at the primary as , while a source resistance appears at the secondary as . A finite magnetizing inductance contributes a parallel branch at the primary; its magnitude must greatly exceed the reflected load for the loaded input to be approximately resistive. The corresponding unloaded secondary self-reactance is . That reactance is distinct from the source's transformed output resistance. A specification that simultaneously calls the loaded input matched to a small resistance and calls the primary impedance very large must distinguish these two branches.
A Thévenin equivalent represents a network at two terminals by a voltage source in series with its Thévenin resistance. It reproduces the terminal relation under the assumptions of Thévenin's theorem.
At fixed pressure, the temperature derivative of a reaction or transformation enthalpy is the corresponding difference in heat capacity at constant pressure:Use a consistent molar or mass basis and retain each phase's range of stability when applying the relation. A latent enthalpy evaluated along a pressure-dependent phase coexistence curve can also have a pressure-variation contribution; the fixed-pressure derivative must not automatically be identified with that full derivative.
Radio communication conveys information using radio waves coupled into and out of space by antennas. Amplitude modulation and frequency modulation vary a carrier wave; wireless telegraphy can instead encode symbols in transmission intervals. The useful separation is between the rapid electrical oscillation and the slower message timing. A receiver needs both frequency selection and a way to turn its selected signal into a readable output.
Telegraphy represents written symbols by agreed sequences of distinguishable signals. In wireless telegraphy, a key can select short and long transmission intervals; a receiver must recover their timing, rather than reproduce every rapid electrical oscillation as a visible mark.
The convention used here chooses units in which the numerical values of the reduced Planck constant, electron mass, elementary charge and times the vacuum permittivity are one.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.Figure 3. Visual Studio Code extension installation.Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. - Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact





