Model-based development

Current pharmacometrics practices and available techniques for model-based development are heavily constrained by a vision of model-based development as a subsidiary development process in an empirical development paradigm. Many of the symptoms of the less than optimal functioning of pharmacometrics in this setting are the result of a failure to appreciate the true needs and requirements of the pharmacometrics group. In this chapter, we use the term pharmacometrics enterprise to denote the need to transform the current pharmacometrics analysis process to an interdependent enterprise capable of managing the growing complexity of the critical upstream and downstream implications of a fully functional and accountable service. The design of a pharmacometrics enterprise that embodies the required elements is a novel and complex endeavor that can overtax the experience and... 

Rigorous techniques for technical effectiveness and performance measurement exist and have been used for years and must be mined for applicable lessons and directions for the pharmacometrics enterprise. The development of an integrated solution to these strategic and technical challenges is a particularly difficult, but nonetheless crucial, effort that will define the level of performance achievable by a pharmacometrics service in model-based development. 

RTCA/DO-331, 2011. Model-based Development and Verification Supplement to DO-178C and DO-278A. RTCA Inc., Washington, DC. 

Changing the view from a user of products to a developer of variant products and focusing on a V-Model based development the variability problem arises in every development stage as illustrated in Fig. 17.1 (see also Chap. 9). 

TCs derived from non-formal specifieations by testers with thorough domain knowledge model-based development with SCADE (MiUus and Steinke 2010). 

The model-based development and verification supplement has proved to be the most contentious of all the supplements. At the time of writing, it had still not been approved by plenary. 

A model is an abstract representation of a system. In software development, models ean be used to capture software requirements and/or software designs. Code ean often be generated automatically from a design model. Examples of model-based development and verification tools include Simulink and SCADE. 

Model-based development and verification promises many advantages for safety-critical software development ... 

However, model-based development and verification also presents a number of challenges ... 

A key principle encapsulated in the model-based development and verification supplement is that every model must be verified against the requirements from which it was developed. 

Rusch K, Maletic B, Chatteijee D, Bauknecht M, Kneifel A, Niemeyer J (2012) Model-Based Development of an SCR System for Railcars. Paper presented at the 5th International CTI Conference Emission Reduction for Off-Highway Applications, Lindau, Germany, 26-27 Sep 2012... 

Model-based development of software has become more and more common over the years. Software can be designed and verified using behavioral models developed in e.g. Simulink [1], which is one of the most popular tools for this purpose. For safety-related software developed in Simulink, compliance with recommendations from functional safety standards may be required. For example, if the international standards lEC 61508 [2] or ISO 26262 [3] are used, they require that systems shall be able to handle faults, and fault injection is either recommended or mandatory according to these standards. Fault injection is an experimental method to exercise and evaluate error detection and recovery mechanisms, and it can also be used in an iterative manner to improve software robustness. 

The cross-domain safety assurance process outlined in Sec. 3 is applicable to any development process or methodology, since none of the process steps directly include a reference to the system development. Hence, our approach may be used along with state-of-the-art approaches in system/software engineering such as component-based and model-based development as well as software-product-lines. 

Choi, Y. Jang, H. (2010). Reverse engineering abstract components for model-based development and verification of embedded software, 12th IEEE International Symposium on High-Assurance Systems Engineering (HASE IO) pp. 122-131. 

Model-based development of software systems, and of interactive computing systems in particular, promotes a development life cycle in which models guide the development process, and are iteratively refined xmtil the source code of the system is obtained. Models can be used to capture, not only the envisaged design, but also its rational, thus documenting the decision process xmdertook during development. Hence, they provide valuable information for the maintenance and evolution of the systems. 

Keywords Safety Case, Dependability Case, Argiunent structures, Argument Assessment, Quality models, Model-based development. 

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