Midterms Flashcards
From the Greek word “systema”, meaning an organized whole
System
Came into being though natural processes
Natural Systems
Those that have been developed by human beings
Man-Made Systems
Made up of real components occupying space
Physical Systems
An organization of ideas, a set of specification and plans
Conceptual Systems
Those that have structure, but without activity
Static Systems
One that combines structural components with activity
Dynamic Systems
relatively self-contained and does not significantly interact with its environment
Closed System
Interact with their environment
Ex. Support Capability
Open-Loop System
A collection of components systems that produce results unachievable by the individual systems alone.
System of Systems (SOS)
Parts of the System, elements of which the system is composed
Components
Properties of the individual components
Attributes
Between (pairs of) components so that the components interact to support the system’s functionality (common purpose)
Relationships
Values of the attributes and relationships at a particular moment
State
A type of components that is static
Structural Components
Dynamic Components which “do the work”
Operating Components
Things which change, such as information, energy or material
Flow Components
Color, strength, size, weight, and power
Attribute of Components
if 2 hierarchical levels are involved in a given system, the lower is conveniently called subsystem
Systems and subsystems
Anything outside the system of the boundaries of the system is considered ___
Environment
An interdisciplinary approach and means to enable the realization of successful systems (INCOSE)
Systems Engineering
Defined as a methodical, multi-disciplinary approach for the design, realization, technical management, operations, and retirement of a system
Systems Engineering
That is, we say that a project is delivering a system, or is delivering a product
System as a product
Systems are much more than just the aggregation of hardware or software products
System as a Capability
A capability (in systems engineering) is created through the proper and effective interaction of people, process and technology
Capability System
A logical description of a system, the system’s mission is broken down into a hierarchical structure of its major functions - to form a functional hierarchy
Logical (Functional) Hierarchy
Here we can use a simple 4 - layer (common) representation of a system
Physical Hierarchy
Phase where the life cycle begins with the ________ phase with an idea for a system being generated as a result of a business planning
Pre-Acquisition Phase
This phase is focused on bringing the systems into being and into the service of the organization
Acquisition Phase
The system is operated (also supported) during the _____
Utilization phase
This phase could also be a mark of another life cycle
Retirement Phase
A Phase where design is the formal transition from the business world to the project world, i.e. from the mission statement to complete logical description of the system of interest
Conceptual Design Phase
Articulated and confirmed by the business management
Business Needs and Requirements (BNR)
BNR are elaborated by the stakeholders at the business operations level into a set of ______
Stakeholders Needs and Requirements
SNR are elaborated by requirements engineering into system requirements in the ________
System Requirements Specifications (SyRS)
BNR, SNR, and the SyRS are the key elements to establishing the _________
Functional Baseline (BSL)
Conceptual Design ends with the ______
Systems Design Review (SDR)
Converts the logical architecture of the initial FBL into descriptions of the physical subsystems (upper-level physical architecture) that will meet system requirements.
Preliminary Design Phase
Uses engineering disciplines to develop the individual subsystems, assemblies
Detailed Design & Development
Review at the end of this activity is called the ________
Critical Design Review (CDR)
Components are produced in accordance with the PBL specifications
Construction and/or Production
Major activities in the phase are:
- Operational use
- System support
Utilization and Retirement Phase
A linear and sequential approach where each phase (e.g., requirements, design, implementation, testing, deployment) is completed before the next one begins.
The Waterfall Model
(an extension of the Waterfall model) where development stages are paired with corresponding testing stages
“V” Model
Well-suited for projects where requirements are expected to evolve over time, and where feedback and refinement are critical to achieving the desired outcomes.
The Iterative Model
Emphasizes iterative development, strong focus on risk management and flexibility
Spiral Model
Completed and accurate definition is fundamental to project success.
Requirements Engineering
is required so that design decisions can be traced from any given system-level requirements down to a detailed design decision
Forward Traceablity
any lower-level requirement is associated with at least one higher level requirements
Backward traceability
Assures the customer that all requirements can be accounted for in the design at any stage
Traceability
Systems Engineering maintains a life-cycle focus as decisions are made
Life Cycle Focus
Systems Engineering is looking for optimal system-level performance.
System Optimization and Balance
Systems Engineering integrates a diverse range of technical disciplines and specializations
Integration of Specializations/Disciplines
Systems Engineering clearly has a technical role but also needs to have a very important management role.
Management
We concentrate on the intent and main aim of each application of this foundation process
Systems Engineering Processes
Oversees the systems engineering process
Systems Engineering Management
Tools are available to help managers and process people undertake their tasks
Systems Engineering Tools
Technical and non-technical disciplines are related to systems engineering
Related Disciplines
Systems Engineering relies on the continual application of the simple problem-solving process of ______, _______, and ________
Synthesis, Analysis, and Evaluation
Commences with the perceived need for the system
Analysis
the “design” and “creation” functions
Synthesis
________ is performed throughout its life-cycle:
Evaluation
The basic analysis - synthesis - evaluation loop is applied iteratively throughout the system life cycle
Systems Engineering Process
Elements are attributed to the source and are normally gathered via interview or workshop
Elicitation
Entails breaking a higher-level requirements into those lower-level requirements that are explicitly required by it.
Decomposition
Requirements engineering drawing some inference. The stakeholder did not mention the req’t directly but the derived req’t is necessary part of the system design if one or more directly stated requirements is to be met
Derivation
_______ and ________ are not for novices and require requirements engineers (or business analysis) to understand
Elicitation/Elaboration
A the result of the formal transformation of one or more needs into an agreed-to obligation from an entity to perform some function or possess some quality (within specified constraints)
Requirements
Something that the system should do or provide
Functional Requirement
Some property, quality or attribute, that the system must possess, a condition that must be met, or a constraint under which is must operate or be developed
Non-functional requirement
The first and most important phase of the system design and development process
Conceptual System Design
Given that identified need for a system, the next stage of system planning and architecting can be initiated called the Program Management Plan (PMP)
System Planning and Architecting
Identify various system-level design alternatives that could be pursued in response to the need
System Design and Feasibility Analysis
Once the need and technical approach have been defined, it is necessary to translate this into some form of “operational scenario” or a set of operational requirements
System Operational Requirements
Identification of the prime and secondary (alternative) missions of the system
Mission Definition
Definition of the operating characteristics and functions (size, weight, speed, range, accuracy, flow rate, capacity, transmit, receive, throughput etc.)
Performance and Physical Parameters
Identification of the quantity of equipment, software, personnel, facilities, (and so on) and the expected geographical location to include transportation and mobility requirements
Operational Deployment and Distribution
Anticipated time that the system will be in operational use
Operational life cycle (horizon)
Anticipated usage of the system and its elements
Utilization requirements
System requirements specified as figures-of-merit (FoMs)
Effectiveness factors
Definition of the environment in which the system is expected to operate
Environmental factors
The prime system elements must be designed in such a way that they can be efficiently and effectively supported through the entire system life cycle and the maintenance and support infrastructure must be responsive to this requirement
System Maintenance and Support
Include corrective and preventive maintenance
Levels of maintenance
dictate that an item (in the event of failure) is nonrepairable, partially repairable, or fully repairable.
Repair Policies
may be responsibility of the customer, producer (supplier), or a third-party
Organizational responsibilities
Criteria must be established for the various elements of maintenance support
Maintenance Support Elements
Consist of the effectiveness factors associated with the support capability
Effectiveness requirements
This includes temperature, shock and vibration, humidity noise, arctic vs tropical environment, mountainous vs flat terrain, shipboard vs ground conditions
Environment
The objective here is to derive the overall performance goals (and be clear) as to which the system must be designed.
Technical Performance Measures
Team approach to help ensure that the voice of customer is reflected in the ultimate design
Quality Function Deployment
Functional analysis is the iterative process of breaking down requirements from the system-level, to the subsystem, and so on to identify input design criteria
Functional Analysis and Identification
At this point, decisions must be made regarding:
System Trade off Analysis
The results from the previous activities are used to establish the specific “design-to” requirements for the system (the ultimate objective of this stage)
System Specifications
Design information is released and reviewed for compliance with the basic system-equipment requirements.
Conceptual Design Review
Causality driven, holistic approach to describing the interactive relationships between components inside a system as well as influences from outside the system
Systems Thinking
Methodology used to study the behavior of complex systems over time
System Dynamics
Refers to how key variables in a system change over time
System Behavior
When an initial quantity of something starts to grow, and the rate of growth increases
Exponential Growth
When the quantity of interest starts either above or below a goal level and over time moves towards the goal
Goal-seeking behavior
When initial exponential growth is followed by goal-seeking behavior, which results in the variable leveling off
S-shaped Growth
When the quantity of interest fluctuates around some level
Oscillation
Snapshot of all relationship that matter
Causal Loop Diagrams
Components of system that can change overtime
Variables
Links between variables are the verbs in the system
Links
Reinforcing loop is a loop that amplifies changes in system
Feedback loop
Shows relationship among variables which have the potential to change overtime
Stocks and Flow Diagrams
Accumulation of stuff, either concrete, such as dollars or groundwater that can increase or decrease overtime
Stock
Describes actions or processes that transport stuff
Flow
Holds information about the system that affects rate of flows or affects value of another converter
Converter
Moves information from one elements to another
Connector
Can be represented within flow/rate equations or as a distinct item in stocks and flow diagram
Constant
Stocks that lie outside of the model’s boundary
Sources and links
Commonly occurring combination of reinforcing and balancing feedback
System Archetypes
A focused methodology for carefully listening to the voice of the customer (VOC)
Quality Function Deployment