Tracker

Tracker may refer to:

Technology (excluding computers)

Computers

List of G.I. Joe: A Real American Hero characters (S–Z)

This is an alphabetical List of G.I. Joe: A Real American Hero characters whose code names start with the letters S-Z.

Salvo

Salvo is the G.I. Joe Team's Anti-Armor Trooper. His real name is David K. Hasle, and he was born in Arlington, Virginia. Salvo was first released as an action figure in 1990, and again in 2005. Both versions have the T-shirt slogan 'The Right of Might'.

Salvo's primary military specialty is anti-armor trooper. He also specializes in repairing "TOW/Dragon" missiles. Salvo expresses a deep distrust of advanced electronic weaponry. He prefers to use mass quantities of conventional explosives to overwhelm enemy forces.

In the Marvel Comics G.I. Joe series, he first appeared in issue #114. There, he fights as part of a large scale operation against Cobra forces in the fictional country of Benzheen. Steeler, Dusty, Salvo, Rock'N'Roll and Hot Seat get into vehicular based combat against the missile expert Metal-Head He is later part of the Joe team on-site who defends G.I. Joe headquarters in Utah against a Cobra assault.

Tracker (comics)

Tracker is a joint comic book venture of Top Cow Productions and Heroes and Villains Entertainment. It was written by Jonathan Lincoln and has art done by Francis Tsai, Derek Donovan, and Abhishek Malsuni.

History

Tracker premiered at the San Diego Comic-Con International Convention in 2009. Tracker is a five issue comic book mini series written by Jonathan Lincoln with art by Francis Tsai, Derec Donovan and Abhishek Malsuni.

Plot

Tracker tells the story of an FBI agent named Alex O’Roark, whose pursuit of a serial killer leads him to unexplored territory when it is revealed the killer is also a werewolf.

Tracker #1: "Survivor"

FBI Agent Jezebel Kendall is called to the scene of a grisly murder - all passengers on the Blue Line bus have been killed. Jezebel thinks this is the work of Herod, a psychopath killer the FBI has been tracking. Amongst the bodies she finds her partner, Agent Alex O'Roark, barely breathing. Alex miraculously survives, but only with fragmented memories of the incident. He's approached by a mysterious doctor, Cyril Tucker, who tells Alex to contact him once his memory returns. Alex goes back to work; with the help of Agent Isaiah Grant, commander of the FBI's SWAT team, Alex and Jezebel anticipate Herod's next move. Herod kills the only other survivor of the bus attack; Alex tracks him down, but soon loses him. Alex's obsession with the case takes a toll on his personal life. He suddenly loses his temper, has a fight with his girlfriend, Tory Reyes, and storms out. He goes to a bar and leaves a message for Dr. Tucker. After downing shot after shot, yet still unable to wind down, Alex goes looking for trouble, which he finds in the form of a gang threatening a girl. Instead of showing them his badge, he decides to fight them. As the gang swarms over him, Alex transforms into a half-man, half-beast creature and tears the gang apart.

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.

Envelope detector

An envelope detector is an electronic circuit that takes a high-frequency signal as input and provides an output which is the envelope of the original signal. The capacitor in the circuit stores up charge on the rising edge, and releases it slowly through the resistor when the signal falls. The diode in series rectifies the incoming signal, allowing current flow only when the positive input terminal is at a higher potential than the negative input terminal.

Most practical envelope detectors use either half-wave or full-wave rectification of the signal to convert the AC audio input into a pulsed DC signal. Filtering is then used to smooth the final result. This filtering is rarely perfect and some "ripple" is likely to remain on the envelope follower output, particularly for low frequency inputs such as notes from a bass guitar. More filtering gives a smoother result, but decreases the responsiveness; thus, real-world designs must be optimized for the application.

Definition of the envelope