Programs and Communities

Hybrid system models - those devised from two or more disparate sub-system models - provide a number of benefits in terms of conceptualization, development, and assessment of dynamical systems. The decomposition approach helps to formulate complex interactions that are otherwise difficult or impractical to express. However, hybrid model development and usage can introduce complexity that emerges from the composition itself.

To improve assurance of model correctness, sub-systems using disparate modeling formalisms must be integrated above and beyond just the data and control level; their composition must have model specification and simulation execution aspects as well. Poly-formalism composition is one approach to composing models in this manner.

This dissertation describes a poly-formalism composition between a Discrete EVent System specification (DEVS) model and a Cellular Automata (CA) model types. These model specifications have been chosen for their broad applicability in important and emerging domains. An agent-environment domain exemplifies the composition approach. The inherent spatial relations within a CA make it well-suited for environmental representations. Similarly, the component-based nature of agents fits well within the hierarchical component structure of DEVS.

This composition employs the use of a third model, called an interaction model, that includes methods for integrating the two model types at a formalism level, at a systems architecture level, and at a model execution level. A prototype framework using DEVS for the agent model and GRASS for the environment has been developed and is described. Furthermore, this dissertation explains how the concepts of this composition approach are being applied to a real-world research project.

This dissertation expands the tool set modelers in computer science and other disciplines have in order to build hybrid system models, and provides an interaction model for an on-going research project. The concepts and models presented in this dissertation demonstrate the feasibility of composition between discrete-event agents and discrete-time cellular automata. Furthermore, it provides concepts and models that may be applied directly, or used by a modeler to devise compositions for other research efforts.

Professional nurse involvement in shaping the electronic health record continues to be minimal in spite of the presence of shared governance models. The redundancies and nurse dissatisfaction with the electronic health record requires a new approach. The advancement of a shared governance model to a professional governance model has resulted in an increase in professional role involvement in four areas:

1. Accountability.
2. Professional obligation.
3. Collateral relationships.
4. Decision-making.

Increased professional nurse involvement results in, nurses more actively engaged in problem solving to improve nurse satisfaction with the electronic health record. Evidence reflects a positive impact on nurse satisfaction when a professional shared governance structure is in place and guides the professional practice of nurses specific to autonomy and accountability. Additionally, evidence also revealed that nurses have a desire to be included in the quality of design, implementation and sustainability of electronic documentation.

The human papillomavirus (HPV) is the most commonly spread sexually transmitted infection in the United States. Although the HPV vaccine protects against transmission of the most common strains of HPV that cause genital warts and numerous urogenital cancers, uptake in the United States remains suboptimal. Failure to vaccinate leaves individuals vulnerable to the virus and subsequent complications of transmission. The evidence demonstrates that provider recommendation alone increases rates of vaccine uptake. The literature does not suggest a specific method for provider recommendation delivery; however, best practice alerts (BPAs) were correlated with increased vaccination rates.

These findings have directed a proposed project that includes an electronic health record (EHR) change prompting internal medicine, family practice and women’s health providers to educate and recommend the HPV vaccine at a Federally Qualified Health Center (FQHC) in the Southwest United States. The project demonstrates that after the implementation of a practice change of a HPV BPA in the EHR, HPV vaccination rates increased. Practice settings pre and post were similar, making the increase clinically significant.

The strengths of this project include an increase in HPV vaccination rates, a sustainable intervention, and an intervention that can easily be replicated into other health maintenance tasks. There were some limitations including the BPA alert only catching the HPV 9 vaccine series and the BPA did not always capturing historical data. Despite these technical barriers the HPV BPA delivered an increase in the HPV vaccine to protect more individuals from the HPV virus, increased provider adherence to national guidelines, and provides a platform for BPAs to be utilized for other vaccines.