Envelope

An envelope is a common packaging item, usually made of thin flat material. It is designed to contain a flat object, such as a letter or card.

Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a short-arm cross, or a kite. These shapes allow for the creation of the envelope structure by folding the sheet sides around a central rectangular area. In this manner, a rectangle-faced enclosure is formed with an arrangement of four flaps on the reverse side.

Overview

When the folding sequence is such that the last flap to be closed is on a short side it is referred to in commercial envelope manufacture as a pocket - a format frequently employed in the packaging of small quantities of seeds. Although in principle the flaps can be held in place by securing the topmost flap at a single point (for example with a wax seal), generally they are pasted or gummed together at the overlaps. They are most commonly used for enclosing and sending mail (letters) through a prepaid-postage postal system.

Envelope (mathematics)

In geometry, an envelope of a family of curves in the plane is a curve that is tangent to each member of the family at some point. Classically, a point on the envelope can be thought of as the intersection of two "adjacent" curves, meaning the limit of intersections of nearby curves. This idea can be generalized to an envelope of surfaces in space, and so on to higher dimensions.

Envelope of a family of curves

Let each curve C_t in the family be given as the solution of an equation f_t(x, y)=0 (see implicit curve), where t is a parameter. Write F(t, x, y)=f_t(x, y) and assume F is differentiable.

The envelope of the family C_t is then defined as the set of points for which

for some value of t, where is the partial derivative of F with respect to t.

Note that if t and u, t≠u are two values of the parameter then the intersection of the curves C_t and C_u is given by

or equivalently

Letting u→t gives the definition above.

An important special case is when F(t, x, y) is a polynomial in t. This includes, by clearing denominators, the case where F(t, x, y) is a rational function in t. In this case, the definition amounts to t being a double root of F(t, x, y), so the equation of the envelope can be found by setting the discriminant of F to 0.

Synthesizer

A sound synthesizer (usually abbreviated as "synthesizer" or "synth", also spelled "synthesiser") is an electronic musical instrument that generates electric signals that are converted to sound through instrument amplifiers and loudspeakers or headphones. Synthesizers may either imitate the still existing sounds (instruments, vocal, natural sound, etc.), or generate new electronic timbres not existing before. They are often played with a musical keyboard, but they can be controlled via a variety of other input devices, including music sequencers, instrument controllers, fingerboards, guitar synthesizers, wind controllers, and electronic drums. Synthesizers without built-in controllers are often called sound modules, and are controlled via MIDI or CV/Gate using a controller device.

Synthesizers use various methods to generate signal. Among the most popular waveform synthesis techniques are subtractive synthesis, additive synthesis, wavetable synthesis, frequency modulation synthesis, phase distortion synthesis, physical modeling synthesis and sample-based synthesis. Other less common synthesis types (see #Types of synthesis) include subharmonic synthesis, a form of additive synthesis via subharmonics (used by mixture trautonium), and granular synthesis, sample-based synthesis based on grains of sound, generally resulting in soundscapes or clouds.

Overdrive (album)

Overdrive is the second full-length album from Surrey based alternative rock band Fastlane. It was released in May 2007 by Punktastic Recordings.

Track listing

All music composed by Great Cynics.

Personnel

References

External links

Overdrive (Shonen Knife album)

Overdrive is the 19th studio album by pop punk trio Shonen Knife. It was released in 2014 on April 14 (U.K. and Europe), April 15 (North America), April 16 (Japan), and April 18 (Australia and New Zealand). The CD album artwork was created by Masahiko Ohno who is known as "Solmania" and there are three different colors for Japan, North America, and U.K./Europe.

The album received moderately positive reviews from critics. Many applauded the band's dabbling in more harder rock, whereas others were critical of the album's musical and lyrical simplicity.

Production

While Shonen Knife's usual sound is Ramones-inspired pop punk, for Overdrive, the band branched out musically and listened to harder rock bands—such as Black Sabbath, Thin Lizzy, Bad Company, Deep Purple, Judas Priest, Boston, ZZ Top, and The Doobie Brothers—for inspiration. I Am Tuned Up has described the album's sound as a combination of "edgy guitar riffs with psychedelic 70s-esque enchanting nostalgia."Naoko Yamano reasoned that, because that Free Time (2010) was heavily influenced by punk rock, and Pop Tune (2012) explored a more pop-oriented sound, Overdrive represented an opportunity for the band to explore harder rock. In fact, the album's name is a reference to the overdrive pedal, which, in Yamano's mind, conjured up images of 1970s rock music.

Overdrive (comics)

Overdrive is a fictional comic book supervillain, appearing in books published by Marvel Comics, usually as an enemy of Spider-Man. Created by Dan Slott, and Phil Jimenez, Overdrive first appeared in Amazing Spider-Man: Swing Shift (May 2007), a Free Comic Book Day issue set after the events of the Spider-Man: One More Day storyline.

Publication history

Overdrive was created by Dan Slott and Phil Jimenez and first appeared in Free Comic Book Day 2007.

Something of a throwaway joke character, Overdrive made a few inconsequential appearances throughout Dan Slott's run on The Amazing Spider-Man. As part of Marvel NOW! and the Superior Spider-Man relaunch, Overdrive joined the Sinister Six and features as one of the main characters in Superior Foes of Spider-Man.

Fictional character biography

Overdrive was hired by Mister Negative to steal an artifact from a museum, but was unable to deliver it because of interference from Spider-Man. Overdrive led Spider-Man on a high-speed chase through the streets of Manhattan. When Spider-Man smashed the windshield of Overdrive's car, it revealed dozens of pieces of Spider-Man-related merchandise such as bobble-heads, air-fresheners, and action figures. Overdrive declared that he was Spider-Man's "biggest fan", even asking for an autograph as Spider-Man was trying to stop him.