Hierarchical approaches for systems modeling in cardiac development

Dynamic prediction modeling approaches for cardiac surgery.

BACKGROUND The calibration of several cardiac clinical prediction models has deteriorated over time. We compare different model fitting approaches for in-hospital mortality after cardiac surgery that adjust for cross-sectional case mix in a heterogeneous patient population. METHODS AND RESULTS Data from >300 000 consecutive cardiac surgery procedures performed at all National Health Service a...

Modeling Approaches in the Early Phases of Information Systems Development

Modelling the real life plays a significant role in Information Systems Development (ISD). There are several approaches that can be utilized, with different emphases on methods and notations. Some of them are well-known, like the traditional process modelling approach, while some newer ones are not widely known, like the Activity Driven Approach. In this paper we study modelling approaches in t...

Modeling Approaches in Embryo Development

Fuzzy Hierarchical Location-Allocation Models for Congested Systems

There exist various service systems that have hierarchical structure. In hierarchical service networks, facilities at different levels provide different types of services. For example, in health care systems, general centers provide low-level services such as primary health care services, while the specialized hospitals provide high-level services. Because of demand congestion in service networ...

Modeling of hierarchical fuzzy systems

A new kind of mapping rule base scheme is proposed to get the fuzzy rules of hierarchical fuzzy systems. The algorithm of this scheme is developed such that one can easily design the involved fuzzy rules in the middle layers of the hierarchical structure. In contrast with the conventional single layer fuzzy controller, the present method has approximate performance using the same scaling factor...