enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Subset sum problem - Wikipedia

    en.wikipedia.org/wiki/Subset_sum_problem

    SSP can also be regarded as an optimization problem: find a subset whose sum is at most T, and subject to that, as close as possible to T. It is NP-hard, but there are several algorithms that can solve it reasonably quickly in practice. SSP is a special case of the knapsack problem and of the multiple subset sum problem.

  3. Proportional–integral–derivative controller - Wikipedia

    en.wikipedia.org/wiki/Proportional–integral...

    Many PID loops control a mechanical device (for example, a valve). Mechanical maintenance can be a major cost and wear leads to control degradation in the form of either stiction or backlash in the mechanical response to an input signal. The rate of mechanical wear is mainly a function of how often a device is activated to make a change.

  4. Technique for human error-rate prediction - Wikipedia

    en.wikipedia.org/wiki/Technique_for_human_error...

    Below is an example of an event tree that represents a system fire: Under the condition that all of a task’s sub-tasks are fully represented within an HRAET and the failure probability for each sub-task is known it is possible to calculate the final reliability for the task.

  5. Halstead complexity measures - Wikipedia

    en.wikipedia.org/wiki/Halstead_complexity_measures

    The difficulty measure is related to the difficulty of the program to write or understand, e.g. when doing code review. The effort measure translates into actual coding time using the following relation, Time required to program: = seconds

  6. Shamir's secret sharing - Wikipedia

    en.wikipedia.org/wiki/Shamir's_secret_sharing

    The following example illustrates the basic idea. Note, however, that calculations in the example are done using integer arithmetic rather than using finite field arithmetic to make the idea easier to understand. Therefore, the example below does not provide perfect secrecy and is not a proper example of Shamir's scheme.

  7. Propagation of uncertainty - Wikipedia

    en.wikipedia.org/wiki/Propagation_of_uncertainty

    Any non-linear differentiable function, (,), of two variables, and , can be expanded as + +. If we take the variance on both sides and use the formula [11] for the variance of a linear combination of variables ⁡ (+) = ⁡ + ⁡ + ⁡ (,), then we obtain | | + | | +, where is the standard deviation of the function , is the standard deviation of , is the standard deviation of and = is the ...

  8. Algorithms for calculating variance - Wikipedia

    en.wikipedia.org/wiki/Algorithms_for_calculating...

    Algorithms for calculating variance play a major role in computational statistics.A key difficulty in the design of good algorithms for this problem is that formulas for the variance may involve sums of squares, which can lead to numerical instability as well as to arithmetic overflow when dealing with large values.

  9. Sample entropy - Wikipedia

    en.wikipedia.org/wiki/Sample_entropy

    Like approximate entropy (ApEn), Sample entropy (SampEn) is a measure of complexity. [1] But it does not include self-similar patterns as ApEn does. For a given embedding dimension, tolerance and number of data points, SampEn is the negative natural logarithm of the probability that if two sets of simultaneous data points of length have distance < then two sets of simultaneous data points of ...