PubMed Health⌕ Search

Biomedical subjects

S L Hardt

Publications and source records attributed to S L Hardt.

3 recordsLinked to original sources

Computer assisted psychiatric diagnosis: experiments in software design.

The process of psychiatric diagnosis involves the real-time utilization of large amounts of knowledge to maintain and test multiple hypotheses. Therefore, the development of an on-line computerized assistant that can aid a clinician performing psychiatric diagnoses presents challenging problems in data-base organization and retrieval. We have developed the DUNE (Diagnostic Understanding of Natural Events) system architecture that organizes the knowledge around processing structures. The system was designed as a shell for expert-systems that aid diagnoses and assessment tasks in ill-structured domains in general. These domains have previously proven unfeasible for traditional expert-systems such as rule based systems. Currently, DUNE contains sufficient knowledge to aid the diagnosis of anxiety and affective disorders. Among DUNE's advantages: a large degree of tolerance to clinician errors, and flexibility at run time. In this paper, we discuss the general specifications for a program that can aid psychiatric diagnoses, and then describe DUNE and its capabilities.

Adolescent↗

Rates of diffusion controlled reactions in one, two and three dimensions.

The dimensionality of diffusion may markedly affect the rate and economy of diffusion controlled reactions. Moreover, the degree of dependence of the steady state rate of these reactions on the concentration of each of the two reacting species is also dictated by the dimensionality and it ranges from linear dependence in the three dimensional case to a nearly square dependence in the one dimensional case. These theoretical observations emerge from a direct analysis of the steady state diffusion controlled rates which are derived here using a simple straightforward approach. This approach is based on the conjecture that in the steady state the rate of diffusional encounters between the two reaction partners equals to the sum of the encounter rates of two independent processes which are obtained by alternately immobilizing one of the reaction partners while the other partner diffuses freely. Unlike Smoluchowski's classical approach, the presented point of view permits to obtain in a unified fashion reaction rates for all dimensionalities.

Journal Article↗