In some process monitoring situations, consecutive measurements are spaced widely apart in time, making monitoring process aim and spread difficult. This study uses three cases to compare the effectiveness of two such monitoring schemes, i.e., the X chart alone (X-only chart) and the Individuals and Moving Range Chart Combination (X/MR chars), in terms of Average Run Length (ARL) after designin...

Article history: Received 18 November 2011 Accepted 15 October 2012 Available online 5 November 2012

A new feature set derived from the fractal geometry, called the random threshold vector (RTV) is proposed for texture analysis. The RTV is computed for different run length entropy dimensions. The run length entropy dimensions are calculated based on different thresholds. To test the rotationally invariant feature, the run length entropies are calculated in different directions. The experimenta...

We present a new CuSum chart for monitoring shifts in the mean of autocorrelated data. The monitoring statistic is the plain cumulative sum of differences between the observations and the target value, and the control limits are a function of the asymptotic variance constant and target in-control average run length. Our method uses a variety of non-parametric techniques that are popular in the ...

The paper studies the optimal production run length for a deteriorating production system. The optimal warranty cost is determined by a balance between the warranty cost of the manufacturer and the buyer during its warranty period. It is assumed that the elapsed time until the production process shift is age dependent and arbitrarily distributed. The objective is to minimize the total cost per ...

In reality, the process observations are away from the assumption that are normal distributed. The observations could be skew distributions which should use an asymmetric chart rather than symmetric chart. Consequently, this research aim to study the robustness of the asymmetric Tukey’s control chart for skew and non-skew distributions as Lognormal and Laplace distributions. Furthermore, the pe...

Parameterized matching between two strings occurs when it is possible to reduce the first one to the second by a renaming of the alphabet symbols. We present an algorithm for searching for parameterized occurrences of a patten in a textstring when both are given in run-length encoded form. The proposed method extends to alphabets of arbitrary yet constant size with O (|rp| × |rt|) time bounds, ...

Surveillance can be based, in some change-point detection problems, on a sequence of invariant statistics. Gordon and Pollak (1997) prove that, under certain conditions, the Average Run Length (ARL) to false alarm of invariance-based Shiryayev-Roberts detection schemes is asymptotically the same as that of the dual classical scheme that is based on the original sequence of observations. In this...

Bounds on the capacity of constrained two-dimensional (2-D) codes are presented. The bounds of Calkin and Wilf apply to first-order symmetric constraints. The bounds are generalized in a weaker form to higher order and nonsymmetric constraints. Results are given for constraints specified by run-length limits or a minimum distance between pixels of a given value.

We show that there is no batch-means estimation procedure for consistently estimating the asymptotic variance when the number of batches is held fixed as the run length increases. This result suggests that the number of batches should increase as the run length increases for sequential stopping rules based on batch means.