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Total Lifecycle Management, Program Manager, Light-Armored Vehicles, United States Marine Corps
We are developing and enacting an approach to requirements engineering and design for highly distributed planning and decision making applications with complex data source requirements. The target system is intended to provide total life cycle management (TLCM) support to Marine Corps planners for combat ground vehicles. The objective of the TLCM project is to provide Marine Corps planners with information technology to help increase weapon system asset visibility, improve system readiness and sustainment, and reduce overall system lifecycle costs. At the heart of the approach is the use of scenarios as the fundamental unit of analysis in requirements engineering, design, and evaluation. Scenario-based design and scenario-based evaluation allow us to focus all analysis, design, and evaluation activity on the actual use context of the envisioned, rather than on abstract statements about a system's desired properties. Scenarios act as a focusing mechanism for understanding how a particular system supports actual human activity and how it fits into the technical, psychological, and organizational environment for which it is intended. The general approach we propose to take to TLCM-AT data requirements analysis is scenario-based design and related analysis techniques, including claims analysis. The essence of scenario-based methods is that system design and evaluation should be grounded in the concrete use scenarios for which design is intended. Scenarios are narratives that describe details of a user interaction with a system or application. In addition to the main scenario narrative, a scenario unit also includes an identified actor (user and/or stakeholder), which may be a specified individual but typically is represented as a prototypical role; a setting describing the context in which the scenario occurs; task goals describing the motivation behind performing a scenario; and claims, which are statements about the effects or consequences of providing system support for the scenario. Claims are a critical component of the evaluation approach. Claims are the mechanism by which system designers or analysts reflect on the design to consider what is 'right' (positive claims) and what is 'wrong' (negative claims) with respect to system support for a given scenario. One of the key attributes of the SBD/CA technique is its relative simplicity and the focus on a single representation, claims, for capturing design reasoning and design knowledge. Scenario-based design and claims analysis is a relatively simple technique for designers to pick up and use with minimal training, though their relative lack of structure places significant demands on computational services that attempt to manipulate the data they produce. One approach suggested to help structure claims data with additional classifying information is to create claims taxonomies representing the underlying objectives, environment, and constraints of the specific claims analysis effort. The concept diagram below shows the overall process including an example claims taxonomy for the TLCM effort.
TLCM Method Concept |
