We have developed and implemented in the QPORTRAIT program a qualitative simulation based method to construct phase portraits for a significant class of systems of two coupled first order autonomous differential equations, even in the presence of incomplete, qualitative knowledge. Differential equation models are important for reasoning about physical systems. The field of nonlinear dynamics ha...

We have developed a qualitative method to assay for the presence of 2-deoxystreptamine in hydrolysates of crude aminoglycoside preparations using a 2-deoxystreptamine-requiring idiotrophic mutant. The assay involves (i) incubation of a 2-deoxystreptamine-requiring mutant with 1 mg of a hydrolyzed preparation from a crude unknown antibiotic mixture per ml, and (ii) examination of the resultant i...

Mixed methods, defined as one complete method (as the core project) plus a different simultaneous and sequential supplemental strategy, have been well explicated for combining the most difficult designs—that is, qualitative and quantitative methods. However, experts in qualitative inquiry have relatively ignored the issues that occur while describing qualitative simultaneous and sequential desi...

1. The communication model Communication is not simply just information processing from a sender to a recipient. It is an interactive process that has its own specific dynamics by which the communicators themselves become entangled in the topic of the communication. The meaning of any message results from the context in which it is placed and can be understood on three different levels. Take a ...

The Focus Group (FG) has been actually employed by marketing, and is becoming importanct also in other areas; such as, education, health, management, decision-making, and information systems, among others. Depending on the research objective, the Focus Group can be used alone or in conjunction with other methods. The results obtained from the FG application are particularly effective in supplyi...