A word w is called synchronizing (recurrent, reset, directed) word of a deterministic finite automaton (DFA) if w sends all states of the automaton on a unique state. Jan Černy had found in 1964 a sequence of n-state complete DFA with shortest synchronizing word of length (n − 1). He had conjectured that it is an upper bound for the length of the shortest synchronizing word for any n-state comp...

Cytospin-enhanced direct fluorescent-antibody assay (DFA) detected 49 (92.5%) and rapid membrane enzyme-linked immunosorbent assay (ELISA) detected 40 (75.5%) of 53 influenza virus A-positive samples. All 15 positive nasopharyngeal aspirates from children were detected by both tests. In contrast, 34 of 38 (89.5%) positive swabs from adults were detected by DFA, but only 25 (66%) were detected b...

A cytotoxicity assay with Chinese hamster ovary cells (CHO) capable of detecting 750 pg of pertussis toxin was assessed for use as a rapid test for the diagnosis of pertussis and compared with direct immunofluorescence (DFA). With pure bacterial cultures and simulated clinical specimens, the CHO assay detected as few as two colonies of Bordetella pertussis; no cytotoxicity occurred with other r...

The laboratory diagnosis of varicella-zoster virus (VZV) infection was reevaluated by direct immunofluorescent-antibody staining (DFA) and centrifugation culture with newly available murine monoclonal antibodies. Specimen smears were examined by DFA using monoclonal antibodies to VZV and to herpes simplex virus types 1 and 2. Specimens were also inoculated into shell vials for centrifugation cu...

This paper presents a novel face detection method by applying discriminating feature analysis (DFA) and support vector machine (SVM). The novelty of our DFA–SVM method comes from the integration of DFA, face class modeling, and SVM for face detection. First, DFA derives a discriminating feature vector by combining the input image, its 1-D Haar wavelet representation, and its amplitude projectio...

Cloud storage, and more specifically the encryption of file contents to protect them in the cloud, can interfere with access to these files by partially trusted third-party service providers and customers. To support such access for pattern-matching applications (e.g., malware scanning), we present a protocol that enables a client authorized by the data owner to evaluate a deterministic finite ...

Learning Deterministic Finite Automata (DFA) is a hard task that has been much studied within machine learning and evolutionary computation research. This paper presents a new method for evolving DFAs, where only the transition matrix is evolved, and the state labels are chosen to optimize the fit between final states and training set labels. This new procedure reduces the size and in particula...