Background: Enzymatic hydrolysis of lactose is one of the most important biotechnological processes in the food industry, which is accomplished by enzyme β-galactosidase (β-gal, β-D-galactoside galactohydrolase, EC 3.2.1.23), trivial called lactase. Orthogonal arrays design is an appropriate option for the optimization of biotechnological processes for the production of microbial...

Chitinase production by newly isolated Serratia marcescens B4A was optimized following Taguchi’sarray methods. Twenty-three bacterial isolates were screened from shrimp culture ponds in the South ofIran. A chitinase-producing bacterium was isolated based on it’s ability to utilize chitin as the sole carbonsource. The isolate designated as B4A, was identified as Serratia marces...

To date very few results are known on the critical sets for a set of Mutually Orthogonal Latin Squares(MOLS). In this paper, we consider Orthogonal Array OA(n, k + 2, n, 2) constructed from k mutually orthogonal cyclic latin squares of order n and obtain bounds on the possible sizes of the minimal critical sets. In particular, for n = 7 we exhibit a critical set, thereby improving the bound rep...

In this paper, we relate the problem of generating all 2-level orthogonal arrays of given dimension and force, i.e. elements in OA(n, m), where n is the number of factors and m the force, to the solution of an Integer Programming problem involving rational convex cones. We do not restrict the number of points in the array, i.e. we admit any number of replications. This problem can be theoretica...

background: xanthomonas citri subsp. citri (xcc), the causative agent of bacterial citrus canker, has affected citriculture worldwide. varieties of means have been used to minimize its devastating effects, but no attention has been given to bacteriocins.objectives: here and for the first time, we report the isolation and characterization of two novel bacteriocins.materials and methods: secretom...

multiple input multiple output (mimo) radars are new generation of array radars that employ orthogonal waveforms for their transmit probing signals. despite of several advantages, this strategy results in transmission of uniform power in all angle of array’s viewing field. therefore, possibility of transmit beamforming and achieving coherent processing gain will be lost. many efforts have been ...

The concept of a linear ordered orthogonal array is introduced, and its equivalent geometrical configuration is determined when its strength is 3 and 4. Existence of such geometrical configurations is investigated. They are also useful in the study of (T, M, S)-nets.

(say) is called symmetric, otherwise, the array is said to be asymmetric. Several methods of construction of symmetric as well as asymmetric OAs are available in the literature. Some important methods will be discussed here. One of the principal applications of the OAs is in the selection of level combinations for fractional factorial experiments. An OA of strength t is equivalent to an orthogo...

We consider the problem of existence perfect 2-colorings (equitable 2-partitions) Hamming graphs with given parameters. start conditions on parameters and colorings that are necessary for their existence. Next we observe known constructions propose some new ones giving At last, deduce which covered by these give tables admissible in H ( n , q ) small q. Using connection colorings, construct an ...

Due to run size constraints, near-orthogonal arrays (near-OAs) and supersaturated designs, a special case of near-OA, are considered good alternatives to OAs. This paper shows (i) a combinatorial relationship between a mixed-level array and a nonresolvable incomplete block design (IBD) with varying replications (and its dual, a resolvable IBD with varying block sizes); (ii) the relationship bet...