the binary and ternary codes spanned by the rows of the point by block incidence matrices of some 2-designs and their complementary and orthogonal designs are studied. a new method is also introduced to study optimal codes.

Nanoporous carbons (CMK-3) were prepared and have been used as a fiber coating for headspace solid phase microextraction (HS-SPME). The prepared materials were characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and N2 adsorption/desorption isotherms. The efficiency of the fiber was evaluated using a gas chromatography (GC) system for the extraction of benzene (B) and c...

Orthogonal arrays are widely used in industrial experiments for factor screening. Suppose only a few of the factors in the experiments turn out to be important. An orthogonal array can be used not only for screening factors but also for detecting interactions among a subset of active factors. In this article, a set of optimality criteria is proposed to assess the performance of designs for fact...

A (symmetric) nested orthogonal array is a symmetric orthogonal array OA(N, k, s, g) which contains an OA(M,k, r, g) as a subarray, where M < N and r < s. In this communication, some methods of construction of nested symmetric orthogonal arrays are given. Asymmetric nested orthogonal arrays are defined and a few methods of their construction are described.