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  2. Position weight matrix - Wikipedia

    en.wikipedia.org/wiki/Position_weight_matrix

    A PWM has one row for each symbol of the alphabet (4 rows for nucleotides in DNA sequences or 20 rows for amino acids in protein sequences) and one column for each position in the pattern. In the first step in constructing a PWM, a basic position frequency matrix (PFM) is created by counting the occurrences of each nucleotide at each position.

  3. Pulse-width modulation - Wikipedia

    en.wikipedia.org/wiki/Pulse-width_modulation

    The PWM switching frequency can vary greatly depending on load and application. For example, switching only has to be done several times a minute in an electric stove; 100 or 120 Hz (double of the utility frequency ) in a lamp dimmer ; between a few kilohertz (kHz) and tens of kHz for a motor drive; and well into the tens or hundreds of kHz in ...

  4. Random pulse-width modulation - Wikipedia

    en.wikipedia.org/wiki/Random_pulse-width_modulation

    In RPWM, one of the switching parameters of the PWM signal, such as switching frequency, pulse position and duty cycle are varied randomly in order to spread the energy of the PWM signal. Hence, depending on the parameter which is made random, RPWM can be classified as random frequency modulation (RFM), random pulse-position modulation (RPPM ...

  5. Motor constants - Wikipedia

    en.wikipedia.org/wiki/Motor_constants

    On the other hand, if the motor is driven as a generator, the no-load voltage between terminals is perfectly proportional to the RPM and true to the of the motor/generator. The terms K e {\displaystyle K_{\text{e}}} , [ 2 ] K b {\displaystyle K_{\text{b}}} are also used, [ 4 ] as are the terms back EMF constant , [ 5 ] [ 6 ] or the generic ...

  6. Pulse generator - Wikipedia

    en.wikipedia.org/wiki/Pulse_generator

    Pulse generators are generally voltage sources, with true current pulse generators being available only from a few suppliers. Pulse generators may use digital techniques, analog techniques, or a combination of both techniques to form the output pulses. For example, the pulse repetition rate and duration may be digitally controlled but the pulse ...

  7. Function generator - Wikipedia

    en.wikipedia.org/wiki/Function_generator

    Frequency stability of 0.1 percent per hour for analog generators [5] or 500 ppm for a digital generator. Maximum sinewave distortion of about 1% (accuracy of diode shaping network) for analog generators. [6] Arbitrary waveform generators may have distortion less than -55 dB below 50 kHz and less than -40 dB above 50 kHz.

  8. Digital pattern generator - Wikipedia

    en.wikipedia.org/wiki/Digital_pattern_generator

    A digital pattern generator is a piece of electronic test equipment or software used to generate digital electronic stimuli. Digital electronics stimuli are a specific kind of electrical waveform varying between two conventional voltages that correspond to two logic states ("low state" and "high state", "0" and "1").

  9. Signal generator - Wikipedia

    en.wikipedia.org/wiki/Signal_generator

    A signal generator is one of a class of electronic devices that generates electrical signals with set properties of amplitude, frequency, and wave shape. These generated signals are used as a stimulus for electronic measurements, typically used in designing, testing, troubleshooting, and repairing electronic or electroacoustic devices, though it often has artistic uses as well.