OBJECTIVE We designed this study to evaluate the simplicity of the user interface in modern-generation mechanical ventilators. We hypothesized that different designs in the user interface could result in different rates of operational failures. SETTING A laboratory in a tertiary teaching hospital. DESIGN Crossover design. SUBJECTS Twenty-one medical resident physicians who did not possess...

Principal component analysis (PCA) was applied to datasets gathering morphological, physiological and reactor performance information, from three toxic shock loads (SL1 - 1.6 mg(detergent)/L; SL2 - 3.1mg(detergent)/L; SL3 - 40 mg(solvent)/L) applied in an expanded granular sludge bed (EGSB) reactor. The PCA allowed the visualization of the main effects caused by the toxics, by clustering the sa...

This paper presents an effective decision making system for leak detection based on multiple generalized linear models and clustering techniques. The training data for the proposed decision system is obtained by setting up an experimental pipeline fully operational distribution system. The system is also equipped with data logging for three variables; namely, inlet pressure, outlet pressure, an...

This paper provides new evidence for the relationship between the nature of banking relationships, managerial ownership and operational performance in supporting reciprocal effects between these variables in the context of small and medium enterprises (SMEs). A simultaneous equations model was applied to a sample of 4,163 Portuguese SMEs and to cross-section data. Evidence was found that these ...

This paper proposes an approach to examining how testing affects the operational behavior of aging software systems. Such an approach requires models for the testing phase and the operational phase that explicitly account for crash failures due to both aging-related and non-aging-related bugs. We develop appropriate semi-Markov models and derive expressions for computing the respective transien...

Compiled knowledge, which allows macro inference steps through an explanation space, can enable explanation-based learning (EBL) systems to reason efficiently in complex domains. Without this knowledge, the explanation of goal concepts is not generally feasible; moreover, the problem of finding the most general operational concept definition is intractable. Unfortunately, the use of compiled kn...

A constraint satisfaction problem (CSP) requires a value, selected from a given ®nite domain, to be assigned to each variable in the problem, so that all constraints relating the variables are satis®ed. Many combinatorial problems in operational research, such as scheduling and timetabling, can be formulated as CSPs. Researchers in arti®cial intelligence (AI) usually adopt a constraint satisfac...