The EWMA chart for the standard deviation is a useful tool for monitoring the variability of a process quality characteristic. The performance of this chart is usually evaluated under the assumption of known parameters. However, in practice, process parameters are estimated from an in-control Phase I data set. A modified EWMA control chart is proposed for monitoring the standard deviation when ...

We report our progress in scaling deductive synthesis and repair of recursive functional Scala programs in the Leon tool. We describe new techniques, including a more precise mechanism for encoding the space of meaningful candidate programs. Our techniques increase the scope of synthesis by expanding the space of programs we can synthesize and by reducing the synthesis time in many cases. As a ...

Two strings x and y are said to be Abelian equivalent if x is a permutation of y, or vice versa. If a string z satisfies z = xy with x and y being Abelian equivalent, then z is said to be an Abelian square. If a string w can be factorized into a sequence v1, . . . , vs of strings such that v1, . . . , vs−1 are all Abelian equivalent and vs is a substring of a permutation of v1, then w is said t...

A repetitive sequence collection is one where portions of a base sequence of length n are repeated many times with small variations, forming a collection of total length N . Examples of such collections are version control data and genome sequences of individuals, where the differences can be expressed by lists of basic edit operations. This paper is devoted to studying ways to store massive se...

Gallager and Van Voorhis have found optimal prefix-free codes κ(K) for a random variable K that is geometrically distributed: Pr[K = k] = p(1 − p) for k ≥ 0. We determine the asymptotic behavior of the expected length Ex[#κ(K)] of these codes as p → 0: Ex[#κ(K)] = log2 1 p + log2 log 2 + 2 + f ( log2 1 p + log2 log 2 )

In this paper, an approach based on the U statistic is first proposed to eliminate the effect of between profile autocorrelation of error terms in Phase-II monitoring of general linear profiles. Then, a control chart based on the adjusted parameter estimates is designed to monitor the parameters of the model. The performance of the proposed method is compared with the ones of some existing meth...

A general method of constructing run-length limited ( , ) constrained codes from arbitrary sequences is introduced. This method is then combined with the method of guided scrambling for constructing a class of weakly constrained codes. The proposed codes are analyzed for the case of = 0 and are shown to give results which are better or comparable to those of the best available codes, however, a...

A new technique for determining carrier diffusion lengths in direct gap semiconductors by cathodoluminescence measurement is presented. Ambipolar diffusion lengths are determined for GaAs quantum well material, bulk GaAs, and AlzGa1-zAs with x up to 0.38. A large increase in the diffusion length is found as x approaches 0.38 and is attributed to an order of magnitude increase in lifetime.

In this paper, we consider a multi-server queuing system in which additional servers are allowed for a longer queue to reduce the customer’s balking and reneging behavior. The customers are assumed to arrive in Poisson fashion and their service- times follow exponential distribution. The number of servers in long run depends on the queue-length. We obtain equilibrium queue size distribution. Th...