The Information Source for Systems Testability and Diagnostics

Systems Engineering Terminology

Assembly – Two or more parts or subassemblies joined together to form a complete unit, structure, or other article.

Assessment – An estimate or determination of the value of a process against a scale of "goodness".

Baseline – A configuration identification document or a set of such documents, formally designated and fixed at a specific time during a configuration item's life cycle.

Bill of Materials – A listing of all subassemblies, intermediate parts, and raw materials that are needed to produce one unit of a finished product.

Block Diagram – A diagram of a system, computer, or device in which the principal parts are represented by suitably annotated geometrical figures to show both the functions of the parts and their functional relationships. (IEEE 610.12-1990)

Bottom-Up – Pertaining to a method or procedure that starts at the lowest level of abstraction and proceeds towards the highest level.

Case Study – A study designed to study intensely one set (or unit) of something as a distinct whole, with the goal of understanding the set as a distinct whole in its particular context.

Certification – The process of confirming that a system or component complies with its specified requirements and is acceptable for operational use.

Compatibility – (1) The ability of two or more systems or components to perform their required functions while sharing the same hardware or software environment.(2) The ability of two or more systems or components to exchange information.

Component – One of the parts that make up a system.

Concept Phase – The identification and exploration of alternative solutions or solution concepts to satisfy a validated need.

Concurrent Engineering – The application of multiple engineering disciplines to develop requirements in several different but related areas at the same time so the requirements and solutions are coordinated and mutually supportive.

Configuration Item (CI) – An item under development that is designated for configuration management.

Configuration Management (CM) – The process of evaluating, approving or disapproving and coordinating changes to configuration items.

Configuration Management Plan (CMP) – The document defining how configuration management will be implemented (including policies and procedures) for a particular acquisition or program.

Commerical Off-the-Shelf (COTS) – A special case of non-developmental item (NDI) that has been developed to meet a commercial strategy and is available for general purchase.

Concept of Operations Document (CONOPS) - A document identifying the ways in which a system or piece of equipment will operate, including any limitations, restrictions, safety factors, reporting capabilities, etc.

Concurrent Engineering – An approach to product development that fosters a unified, collaborative effort by and integrates inputs from business, engineering, manufacturing, and management specialists across the traditionally segregated phases of product development.

Contract Data Requirements List (CDRL) – A form used as the sole list of data and information which the contractor will be obligated to deliver under the contract.

Cost as an Independent Variable (CAIV) – An engineering approach in which analyses center around the ability to meet stated cost objectives.

Cost of Ownership (COO) – The purchase price of equipment plus the cost of operating this equipment over its projected life span .

Critical Design Review (CDR) – A review conducted to determine that the detailed design satisfies the performance and engineering requirements of the development specification.

Data Requirements List (DRL) – A list of data and information to which completion of an engineering effort is judged.

Design Phase – The period of time during which the designs for architecture, components, interfaces, and data are created, documented, and verified to satisfy requirements.

Design Review – A determination of the technical adequacy of the systems engineering and design efforts in meeting system requirements.

Design for Test (DFT) – The practice of adding hardware hooks to integrated circuits in order to facilitate effective, inexpensive testing.

Design for Testability – The aspects of the product design process whose goal is to ensure that the testability of the end product is competently and sufficiently developed.

Engineering and Manufacturing Development (EMD) – That phase of acquisition during which the concepts validated in the previous phase are transformed to system and manufacturing process design.

Fault Management – Those aspects of the system design which cover fault monitoring (detection), fault response, fault storage and fault annunciation, for both operational and maintenance purposes.

Functional Analysis – The process of identifying and determining performance of the functions necessary to achieve mission requirements. Also, the process of examining the characteristics of a defined function to identify all of the sub-functions necessary to the accomplishment of that function.

Life Cycle Cost (LCC) – The total cost of acquisition, operation, maintenance, and support of an item throughout its useful life, and including the cost of dispersal.  

Military Off the Shelf – an existing item designed and in service in other military projects. Also called Non-Developmental Item.

Non-Developmental Item (NDI) – an existing item designed and in service in other military projects. Also called Military Off-the-Shelf.

Reliability, Availability & Maintainability (RAM) – A requirement imposed on acquisition systems to ensure they are operationally ready for use when needed, will successfully perform assigned functions, and can be economically operated and maintained within the scope of logistics concepts and policies.

Request for Proposal (RFP) – A formal process by which the government asks contractors to submit proposals for satisfying a procurement or acquisition requirement.

Systems Engineering – The process of transforming user needs and requirements into an integrated system design solution through concurrent considerations of all life cycle needs including development, test and integration, production, operation and full integration support. Cost and risk reduction are an integral part of Systems Engineering.

Trade Study – A structured process which compares options using predefined performance criteria, to result in the selection of the best design that satisfies all requirements. Trade studies are highly iterative and are used during all development phases to ensure that all factors which might impact a function or requirement are considered.