MADE 3.9.1 User Manual > Glossary
Glossary
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| Term | Acronym | Synonym / Symbol | Definition | Location in MADE |
|---|---|---|---|---|
| Accuracy | ACC | - | Proportion of sensor predictions that are correct. The probability that the sensor will correctly identify any response (either a failure mode or nominal).. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Active Editor | - | - | The Active Editor is the main section of the screen (e.g. System Model or Failure Diagram) currently selected by the user. Tabs of Active editors appear dark blue while inactive editors appear grey. | MADE, RAM, PHM Modules |
| Ambiguity Group | - | Ambiguity Group Size, Fraction of Faults Isolatable, FFI | An ambiguity group displays two or more indistinguishable failure responses of flow properties (Functional Failure Modes) from multiple components. These ambiguous failure modes cannot be distinguished by a sensor or sensor set. The percentage coverage of the sensor set and criticality of the ambiguity group is also displayed. | Ambiguity Group (PHM Module) |
| Ambiguous Failures | - | Ambiguity Group Size | The degree to which the origin of a failure mode can be located and isolated within a system, in terms of the number of suspect items in the group. | Ambiguity Group (PHM Module) |
| Amplitude | - | - | A perturbation variable added to or subtracted from a perturbation value at the time of perturbation for a source or sink. | Response Simulation (Bond Modelling, MADE Module) |
| Amplitude (FCM Simulation) | - | - | Amplitude is a variable added to or subtracted from the Functional Flow Property value at the time of perturbation when conducting a FCM Response Simulation. | Response Simulation (FCM Modelling, MADE Module) |
| Assumption | - | - | A statement, principle, and/or premises offered without proof. | Functional Diagram (All Modules), Functional Hazard Assessment (Project Preferences) |
| Availability | - | - | The proportion of time the system will be operational or capable of fulfilling a stated function to the satisfaction of the user. Availability is usually expressed as a percentage or decimal fraction (0 ≤ n ≤ 1). | ABD & RCM (RAM Module) |
| Back-Fit Reliability Centered Maintenance | B-RCM | Back-Fit RCM | Backfit RCM validates existing maintenance tasks by using information from operations and maintenance in a streamlined analysis, and adjusting task intervals and task content where appropriate. | RCM (RAM Module) |
| Balanced Accuracy | BACC | - | Average of proportion of sensor predictions that correctly identify a failure mode and the proportion of sensor predictions that correctly identify a nominal response. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Bivalent | - | - | A linear graph that can produce two different outputs i.e. nominal(0), and low(-1)/high(1). | Criticality, FCM Threshold (Project Preferences) |
| Bivalent Sigmoid | - | - | A sigmoid is a mathematical function that relates to an S-shaped curve (sigmoid curve). A bivalent sigmoid is capable of providing outputs within the range of 0(low) to 1/-1(high). | Criticality, FCM Threshold (Project Preferences) |
| Breakdown Maintenance | - | - | Maintenance performed on equipment that has broken down and is unusable. It is based on a breakdown maintenance trigger and may be either planned or unplanned. | RCM (RAM Module) |
| Capacitance Factor | - | Capacitance | A perturbation variable multiplied to or divided from a perturbation value at the time of perturbation for a capacitor. | Properties View (Bond Modelling, MADE Module) |
| Causal Strength | - | Strength | Either a hard value between 1 and 10 or a fuzzy value between very low and very high which defines the likelihood or frequency of which a cause (or input flow) generates or perturbs the effect (or target functional output flow) positively or negatively. | Functions Editor & Properties View (All Modules) |
| Cause | - | Root Cause, Failure Cause | An abnormal reason, event or condition which leads to physical degradation or a process leading to a failure mode. A cause can relate to design, manufacture, environmental, operational or maintenance actions or an input flow that exceeds specified limits. | Failure Concepts View (MADE & RAM Modules) |
| Characteristics | - | Part Characteristics, Pair Characteristics | A terms used to define the loading, motion or connection types of equipment. | System Model (MADE & RAM Modules) |
| Characteristic Life | - | Scale Parameter | For a Weibull distribution, this corresponds to a time value when 63.2% of a batch of items have failed. This value is used in conjunction with duration to change the slope of the Weibull curve i.e. a higher characteristic life lowers the probability of failure for a given duration of operation. An increase in the characteristic life of an item will result in an increase of the effective MTTF of that item. Characteristic life for Weibull is most comparable to the MTTF parameter in an exponential distribution. | Criticality & Reliability editor (MADE & RAM Modules) |
| Classic Reliability Centred Maintenance | RCM | Classic RCM | Classic RCM is a maintenance methodology whose objective is to maintain the inherent reliability of the system or equipment design with preventative maintenance, recognizing that changes in inherent reliability may be achievable only through design changes. | Criticality & Reliability editor (MADE & RAM Modules) |
| Compensating Provision | - | Compensating Action, Remedial Action, Operator Action, Corrective Action | Actions that can be taken to negate or mitigate the effect of a failure on a system. | RCM, Component Properties (MADE & RAM Modules) |
| Complex Group | - | - | A RBD or ABD group type which allows an item be assigned as a key item. The group can then be analysed for reliability or availability when the key item is designated as either operation or non-operational. | RBD, ABD (RAM Module) |
| Component | - | [Image: componentLarge.png] | A model item that performs a function and forms part of a larger system. | System Model (All modules) |
| Condition Based Maintenance | CBM | - | A maintenance strategy that monitors the actual condition of the system to decide what maintenance needs to be done i.e. maintenance based on objective evidence of need. | RCM (RAM Module) |
| Connection | - | Interface | A line representing an energy, material or signal flow which connects the function flow of system elements in the system model. | System Model (All Modules) |
| Controllability | C | - | For ISO 26262, controllability describes the ability to avoid a specified harm or damage through timely reactions of the persons involved, possibly with support from external measures. | Criticality Editor (MADE & RAM Modules) |
| Control Measure | - | - | A Control Measure is a concept that is implemented to reduce risk in the system. | Functional Diagram (All Modules) |
| Control Measure Set | - | - | A set of Control Measures applied to Failure Condition to reduce risk in the system. | Functional Diagram (All Modules) |
| Corrective Action | - | Corrective Maintenance, Maintenance Action | A documented design, process, or maintenance procedure implemented in order to correct or mitigate a failure or design deficiency. | Component Properties, RCM (MADE & RAM Modules) |
| Coverage | - | Sensor Coverage, Fraction of Faults Detectable, FFD | The proportion of failures that can be detected and identified by the sensor set under consideration, expressed as a percentage | Sensor Sets Groups, Component Test Points (PHM Module) |
| Criticality | - | - | A measure of the relative risk, consequences and frequency of occurrence of a failure mode, used for the criticality analysis section of a FMECA. Criticality is assigned to each failure mode in order to prioritise corrective or compensating actions to eliminate the failure mode or mitigate its potential effects on the system. | Failure Diagram, Criticality & Reliability editor, FMECA (MADE & RAM Modules) |
| Criticality Analysis | - | - | A procedure by which each potential failure mode is ranked according to priority (e.g. severity or probability of occurrence). Multiple analysis methods include Risk Priority Number (RPN), Criticality Matrix, Failure Assessment Index (FAI), Fuzzy, and Risk Priority Category (RPC). Priority rankings are usually based on the risk of the failure mode, for example in terms of occurrence, severity and detectability. | FMECA analysis and reporting (MADE & RAM Modules) |
| Criticality Number, Failure Mode | - | Cm | The overall, calculated criticality value of a failure mode based on a combination of crisp criticality parameters from a failure path. | Criticality Editor, Reporting (MADE & RAM Modules) |
| Criticality Number, Item | - | Cr | The overall, calculated criticality value of an item based on the summation of all failure mode criticality numbers for a specific component. | Criticality Editor, Reporting (MADE & RAM Modules) |
| Degradation | - | - | An undesirable and gradual decrease of material properties or characteristics of an item, inhibiting its ability to perform a function. | Failure Concepts (All Modules) |
| Delay Time | - | - | That element of down time during which no maintenance is being accomplished on the item because of either supply or administrative delay. | Reliability Editor (RAM Module) |
| Detection Method | - | Method of Detection | The means by which the existence of a failure mode becomes known to relevant personnel. | Component Properties (MADE & RAM Modules) |
| Diagnostic Rule | - | - | A display type which sequentially arranges phrases to describe failure modes based on the most efficient sensor configuration to detect flow type(s). | Diagnostic Sets (PHM Module) |
| Diagnostic Sets Table | - | - | A table displaying the diagnostic properties of a sensor set. These properties include functional flow failures, flow property, failure type, failure response, allocated sensor, sensor reliability, and its assigned component. | Sensor Sets Group (PHM Module) |
| Difficulty of Detection | D | Detectability | A relative measure of the ability to detect the existence of a failure mode used for criticality analysis in a FMECA. Usually measured by a numerical value from 1 to 10 or a fuzzy scale. | Failure Diagram, Criticality & Reliability editor (MADE & RAM Modules) |
| Dmitri Threshold | - | - | A threshold option used in FCM criticality to display an option of 5 different fuzzy values: Very Low, Low, Moderate, High and Very High. | Criticality, Project Preferences |
| Duration of Operation | DurOp | Mission Duration | A time duration in which an item (subsystem, component, part) will be in active operation. In MADE, this value is taken from the item advanced properties or automatically drawn from the Mission Profile if available. | MPD, Criticality & Reliability editor (MADE & RAM Modules) |
| Duty Cycle | - | - | The cycle of operation of a machine or other device which operates intermittently rather than continuously. | MPD, Criticality & Reliability editor, RCM (MADE & RAM Modules) |
| Element | - | Item, Model Item, System Element | A generic term for any sub-system, component, part contained in a system model. | System Model (All Modules) |
| End Effect | - | System Level Effect | The consequence(s) a failure mode has on the operation, functional output of the system at the highest indenture level. | FMEA, FMECA, Fault Injection & Propagation (MADE & RAM Modules) |
| Environment | - | Operational Environment, Operating Conditions | Conditions, circumstances, influences, stresses and combinations surrounding & affecting systems or equipment during storage, handling, transportation, testing, installation, and use in standby status and mission operation. This includes external or internal, man-made or self-induced environments that affect the function, performance, reliability or survival of an item. | MPD (MADE & RAM Modules) |
| Environmental Condition | - | - | The expected environment in which the system is operating at a given moment. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Environmental Event | - | - | An environmental occurrence that is considered abnormal for the system. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Environmental Loading Factor | ELF | - | Environmental Loading Factor represents a ratio between baseline operating environment and applied operating environment. It is used to adjust MTTF values in the MCE analysis as a means to scale cost | Environment Library (All Modules) |
| Environmental Parameters | - | - | A measurable characteristic of the environment surrounding a system or model element. Parameters in MADE include temperature, pressure, humidity, contamination, vibration, shock et al. | MPD (MADE & RAM Modules) |
| Equal Allocation | - | - | Equal Allocation Method calculates Reliability Allocation based on an evenly distributed approach where items in a level of indenture are allocated equal reliability in order to satisfy the target reliability of the parent item. | Reliability Allocation (RAM Module) |
| Exclusion Group | - | - | An exclusion group is created for components that are disregarded in a reliability grouping analysis. | ABD & RBD (RAM Module) |
| Exclusive Path | - | - | A reporting output option that enables the inclusion of the largest failure path within a set of paths. Disabling this option will only include failure path subsets from cause to failure | Reporting (MADE & RAM Modules) |
| Failure | - | - | The event or inoperable state in which any item or part of an item does not or would not perform as previously specified. | All modules |
| Failure Analysis | - | - | The process of collecting and analyzing data to determine the cause of a failure, often with the goal of determining corrective actions or liability. | System Model, Failure Diagram (MADE & SRA Modules) |
| Failure Cause | - | Root Cause | The abnormal state of input, loading or environment that leads to the degradation of an item. | Failure Concepts, Failure Diagram (MADE & RAM Modules) |
| Failure Concept | - | - | An element of a failure mode that defines its cause, progression, state or losses associated with the failure. | Failure Diagram viewer & editor (All Modules) |
| Failure Condition | - | - | A Failure Condition describes the behaviour of a failure mode and its potential effects. | Failure Concepts, Failure Diagram (MADE & RAM Modules) |
| Failure Detection | - | Fault Detection, Detection Methods | The process or method by which occurrence of a failure mode is detected by the operator. Methods Failure detection include visual or audible warning devices, automatic sensing devices, sensing instrumentation, or other unique indications. | Advanced properties (RCM & PHM Modules) |
| Failure Distribution, Exponential | - | - | The exponential failure distribution is a lifetime distribution used for modelling the failure characteristics of items with a constant (or random) failure rate. Electronic components are typically modelled with an exponential failure distribution as they experience little to no predictable physical wear. | Reliability Editor (RAM Module) |
| Failure Distribution, Weibull | - | - | The Weibull failure distribution is a flexible lifetime distribution used for modelling the failure characteristics of items prone to age induced wear. A Weibull distribution approximates three distinct portions of a typical bathtub curve depending on the parameters entered into the Weibull equation. | Reliability Editor (RAM Module) |
| Failure Effect | - | - | The consequence(s) of a failure mode on the functional output of a component, sub-system or system level. Failure effects are classified as Local , Next higher level, and End effects. | FMECA, Fault Injection (MADE & RAM Modules) |
| Failure Identification | FI | - | The process of identifying a specific failure mode that has occurred. | FMECA, FMEA (All Modules) |
| Failure Isolation | - | Fault Isolation | The process of limiting/separating the identified failure from affecting upstream/downstream flows. | PHM Module |
| Failure Localisation | - | Fault Localisation | The process of determining the location of a fault. | PHM Module |
| Failure Mode | FFM | Functional Failure Mode | The observable manner in which a system or system element fails to fulfil its function, expressed in terms of the deviation of its output flow from the specified or nominal limits. | Failure Diagram, FMECA, FMEA (MADE & RAM Modules) |
| Failure Modes and Effects Analysis | FMEA | - | A procedure by which each potential failure mode in a system is identified and analysed to determine its results or effects on the system. | Reporting (MADE & RAM Modules) |
| Failure Mode, Effects and Criticality Analysis | FMECA | - | An extension of FMEA that examines failure mode effects and classifies each failure mode according to its criticality factors (occurrence, severity, difficulty of detection). There are many methods of assessing criticality e.g. RPN, Criticality Number. | Reporting (MADE & RAM Modules) |
| Failure Mode Ratio | FMR | - | The failure mode ratio represents the probability expressed as a decimal fraction that an item will fail in the identified failure mode with respect to other failures. In MADE, failure mode ratio is applied to each failure response of functional failure modes or faults if present in the item failure diagram. MADE normalises all failure mode ratios across all item failure paths. | Failure Diagram (MADE & RAM Modules) |
| Failure Path | - | - | A causal chain of events starting at the initial failure event and ending at the end effect. | Failure Diagram (MADE & RAM Modules) |
| Failure Predictability | - | - | The failure predictability column represents the methods or ability to determine a failure based on symptoms observed. This column captures all symptoms and symptom narratives associated with a failure path. | Failure Diagram, FMECA Maintainability Report (MADE Module) |
| Failure Probability Distribution | - | Reliability Distribution, Life Distribution | A statistical description of the probability of an item failing across a period of time by using cumulative probability distributions. | Criticality & Reliability editor (MADE & RAM Modules) |
| Failure Rate | - | Part Failure Rate | The total number of failures within an item population, divided by the total number of life units expended by that population, during a particular measurement interval under stated conditions. It is a statistical measure of the reliability of a system element, expressed as failures per million hours. The failure rate is assumed to be constant over a given operational scenario. | Criticality & Reliability editor (MADE & RAM Modules) |
| Failure Response | - | Functional Response, system response, Functional Failure Symptom | The changes to functional output flow properties generated in response to the failure propagated from another system element. | Propagation Table (MADE & RAM Modules) |
| False Alarm Rate / False Positive Rate | FAR, FPR | - | Proportion of negatives that not identified as such. The probability that a nominal response when present, will be incorrectly identified as a failure mode (high or low response). | Component Test Point, Sensor Set Groups (PHM Module) |
| False Positive | - | False Alarm | Sensor signalling a failure mode when no failure mode is present. A failure mode, being a non-nominal (high or low) flow property response. | Component Test Point, Sensor Set Groups (PHM Module) |
| False Negative | - | Miss | Sensor signalling no failure mode when a failure mode is present. No failure mode, being a nominal flow property response. | Component Test Point, Sensor Set Groups (PHM Module) |
| False Negative Rate | FNR | Miss rate | Proportion of positives that not identified as such. The probability that a failure mode (high or low response) when present, will be incorrectly identified as nominal. | Component Test Point, Sensor Set Groups (PHM Module) |
| Fault Tree Analysis | FTA | - | A top down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events. | Fault Tree Analysis (MADE, SRA & RAM Modules) |
| Fault | - | - | The physically degraded state of a system element or a change in its behaviour which will result in a failure mode or the inability to carry out its function. | Failure Concepts, Failure Diagram (MADE & RAM Modules) |
| Features | - | - | Specific physical aspects of a part that are the targets of characteristics or origin of failures. | System Model (MADE & RAM Modules) |
| Flow | - | Functional Flow, Input Flow, Output Flow, Flow Type | A change in material, energy or signal with respect to time, expressed as the object of a function. | Function editor (All Modules) |
| FMECA-Maintainability information | - | - | A procedure by which each potential failure is analysed to determine how the failure is detected and the actions to be taken to repair the failure. This analysis is an extension of the FMEA and is dependent upon FMEA generated information. | Reporting (MADE & RAM Modules) |
| Functional Hazard Assessment | FHA | - | A systematic, comprehensive examination of functions to identify and classify Failure Conditions of those functions according to their severity. | Functional Diagram (All Modules) |
| Functional Model | FBD | FBD Model | The representation of a system in which the system elements are defined primarily in term of their functions. | System Model (All Modules) |
| Function | - | - | A description of an operation to be performed by a device, artifact or item, expressed as a verb. | System Model (All Modules) |
| Functional Failure | - | - | The inability of a system to fulfill one or more intended function(s) to a standard of performance that is acceptable to the user of the system. | System Model (All Modules) |
| Fuzzy Criticality | - | - | A criticality analysis method combining fuzzy (non-numerical) rankings of occurrence, severity and difficulty of detection taken from concepts within a failure path to produce a qualitative criticality value. | Properties View, Criticality & Reliability editor (MADE & RAM Modules) |
| Fuzzy Cognitive Mapping | FCM | - | A graphical representation of the knowledge about or the perception of a given system. | System Model (MADE Modules) |
| Hazard | - | - | A source or a situation with potential harm to the system. | Functional Diagram (All Modules), Functional Hazard Assessment (Project Preferences) |
| Hazard Risk Index | HRI | - | The HRI provides a measure of the level of risk, which in turn is used to decide upon the acceptability of that risk and to establish failure prioritisation in a criticality analysis. | FMECA, Reporting (MADE & RAM Modules) |
| Hierarchy Level / Level of Indenture | LOI | System Hierarchy, Indenture Level, Level of Indenture | A method of subdividing and organising the elements of a system model according to the relative complexity of assembly or function of a level. The levels progress from complex (system, subsystem) to simpler (component, part) divisions. | System Model, Reporting (MADE & RAM Modules) |
| In-line | - | - | Simple probes or measuring devices that are placed directly into a process stream. They are used to measure flow properties e.g. pH, temperature, pressure, density, flow etc. | Component Test Point, Sensor Allocation (PHM Module) |
| Incipient Fault | - | - | A defect or physical flaw that is currently developing in a component which can evolve into a failure mode. Incipient Fault terminology can be found in the tool-tip when a fault is highlighted in the failure concepts viewer. | Failure Concepts, Failure Diagrams (MADE & RAM Modules) |
| Induced Failure Mode | IFFM | Induced Functional Failure Mode | Induced failures result either from a physical degradation process within the system or system element or as a result of an erroneous input flow received from another failed system or system element. | Failure Diagram, FMECA, FMEA (MADE & RAM Modules) |
| Inherent Availability | - | - | The probability that, when used under stated conditions in an ideal support environment without consideration for preventive action, a system will operate satisfactorily at any time. | Reliability Block Diagrams (RAM Module) |
| Inherent Reliability | - | - | The reliability of the system without considering critical items. | FCM Reliability (RAM Module) |
| Initial Failure Event | - | - | The first active failure concept node within a failure path that has criticality properties assigned to it. An initial failure event can be a Failure Cause, Fault or Functional Failure Mode (FFM) but is never a Failure Mechanism. | Failure Concepts, Failure Diagram, Criticality Editor (MADE & RAM Modules) |
| Inspection Interval | - | - | The number of operational units (e.g. rounds, miles, hours) between preventive maintenance derived as an outcome of RCM analysis. | RCM, MCE, Advanced Properties (MADE & RAM Modules) |
| Interfaces | - | - | The channels through which systems or system elements interact by the exchange of functional flows. | System Model (MADE & RAM Modules) |
| Level of Indenture | LOI | Hierarchy Level, System Hierarchy, Indenture Level | An item's position in the system hierarchy relative to the top level item. | System Model (All Module) |
| Likelihood Ratio Positive | LRP, LR+ | Positive Likelihood Ratio | Measure of whether the sensor aids in determining if a failure mode is present. The ratio between the probability of a sensor correctly identifying a failure mode and the probability of the sensor misdiagnosing a nominal response as a failure mode. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Likelihood Ratio Negative | LRN, LR- | Negative Likelihood Ratio | Measure of whether the sensor aids in determining if a nominal response is present. The ratio between the probability of a sensor misdiagnosing a failure mode as a nominal response and the probability of a sensor correctly identifying a nominal response. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Line Replaceable Unit | LRU | Line Removable Unit | A unit or essential support item (made up of one or more components) which is removed and replaced at field level to restore the end item to an operationally ready condition. Conversely, a non-LRU is a part, component or assembly used in the repair of a LRU, when the LRU has failed and has been removed from the end item for repair. | Properties View, System Model (MADE Module) |
| Line Replaceable Module | LRM | - | An LRM is an item that can be removed and replaced, typically in the field, at a level lower than a LRU. | Properties View, System Model (MADE Module) |
| Logistics Control Number | LCN | - | The Logistic Control Number (LCN) structure represents a top down physical or functional breakdown of hardware and software for use within Logistics Support Analysis (LSA). | Properties View |
| Local effect | - | - | The consequence(s) of a failure mode on the operation, function or status of the system or system element being analysed. | FMECA, FMEA, Reporting |
| Logical Sensor | - | - | The capability to indirectly detect a failure at one location by combining the outputs of sensors at other locations. | Sensor Analysis Options (PHM Module) |
| Loss | - | Symptom | Material or energy that is emitted from a system element and is not a functional output flow, for example heat loss due to friction. | System Model (All Modules) |
| Maintenance | - | - | All actions necessary for an item to be retained or restored to a specified condition. These actions are performed by personnel having specified skill levels, using prescribed procedures and resources at each prescribed level of maintenance and repair. | RCM, Advanced Properties (MADE & RAM Modules) |
| Maintenance Action | - | - | The combination of all technical and administrative actions, intended to retain an item in or restore it to a state in which it can perform its required function. | RCM, Advanced Properties (MADE & RAM Modules) |
| Maintenance Aware Design Ecosystem | MADE | - | An integrated suite of software tools designed to meet the system engineering requirements for Design, RAMS and PHM aspects of the engineering life cycle. | - |
| Maintenance Interval | - | - | The number of operational units (e.g. rounds, miles, hours) between preventive maintenance derived as an outcome of RCM analysis. | RCM, MCE, Advanced Properties (MADE & RAM Modules) |
| Malfunction | - | - | A condition where the operation of a function is different than intended, excluding the loss of function. | Functional Diagram (All Modules) |
| Matthews Correlation Coefficient | MCC | - | Overall measure of sensor. Where a value of 1 represents perfect predictive ability, 0 represents random predictive ability, and -1 represents total disagreement between prediction and true response. | PHM Module |
| Mean Time To Failure | MTTF | - | Equivalent to MTBF for non-repairable items. In the context of an exponential reliability distribution the MTTF is the inverse of part failure rate. | Criticality & Reliability editor, RCM |
| Mean Time To Repair | MTTR | - | The average time required to repair a failed item. | Criticality & Reliability editor, RCM |
| Mechanism | - | Failure Mechanism | The chemical, electrical, mechanical or software processes which cause physical degradation of a system element and results in a fault. | Failure Concepts, Failure Diagram (MADE & RAM Modules) |
| Mean Time Between Maintenance | MTBM | - | Meantime between maintenance is defined as the average time between Maintenance Actions, including time taken for maintenance to be conducted. | RCM (RAM Module) |
| Mean Time To Failure | MTTF | - | The average time an item will function or perform within their specified limits under stated conditions before failure. For exponential reliability distributions the MTTF is expressed as the inverse of part failure rate. Although MTTF is used for non-repairable items, it is assignable for both repairable and non-repairable items in the MADE system model. | Mission Profile Definitions (All Modules), Advanced Properties (MADE & RAM Modules) |
| Mean Time To Repair | MTTR | - | The meantime to repair represents the average time required to repair a failed item. | Reliability Editor (RAM Module) |
| Minimum Safety Criteria | - | - | A description of minimum benchmark to ensure safety of the system. | Functional Diagram (All Modules), Functional Hazard Assessment (Project Preferences) |
| Mission | - | System Mission | An exercise involving sequential and/or concurrent operations that have been planned in order to achieve one or more stated objectives. | Mission Profile Definitions (All Modules) |
| Mission Event | - | - | An event that occurred/can occur during the Mission Phase. For example, it can be categorised as Operational Event, and Environmental Event. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Mission Profile | MPD | Mission Profile Definition | A time-phased description of the events and environments an item experiences from initiation to completion of a specified Mission which includes mission success criteria or mission critical failures. Mission profiles includes the operating modes of each item in functional terms. | Mission Profile Definitions (All Modules) |
| Mission Time | - | Mission Duration | The total time required to perform a stated mission profile. | Mission Profile Definitions, Advanced Properties (MADE & RAM Modules) |
| Model-based Diagnostics | MBD | - | The process of interpreting sensor output of a system to identify failure modes by comparing the response to the simulated response of a dynamic system model and applying the diagnostic rules developed for the model. | PHM Module |
| Model-based Reasoning | MBR | - | The use of a knowledge-based model of a system application and 'expert'-based decision making rules to assess the response of a system in order to detect and identify a failure mode. | Diagnostic Sets (PHM Module) |
| Negative Predictive Value | NPV | - | Proportion of identified nominal responses that are truly nominal responses. The probability a nominal response will be present when the sensor signals that a nominal response is present. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Next effect | - | Next higher level effect | The consequence(s) of a failure mode on the operation, function, or status of the items in the next higher level of system hierarchy/indenture above the system element from which the failure mode originated. | FMECA, FMEA, Reporting (MADE & RAM Modules) |
| Nominal Path | - | - | A reporting output option that enables the inclusion of causes that do not lead to an end-effect response. | Reporting (MADE & RAM Modules) |
| Non-Detectable Failure | NDF | Undetectable Failure | Failures at the part, component, subsystem or system level that are identifiable by analysis but cannot be identified through periodic testing or in-line sensors. | PHM Module |
| Occurrence | O | - | A relative measure of the frequency of which a failure concept is expected to occur, in either a crisp (1 to 10 ranking) or fuzzy (linguistic e.g. high , very high etc.) value. A higher occurrence will result in a higher criticality value. | Criticality Editor, Mission Profile Definitions & Functional Diagram (All Modules) |
| Occurrence, Apparent | App. O | - | The overall likelihood or frequency of a failure path occurring and resulting an end-effect. It is calculated using a combination of two fuzzy (linguistic) parameters, Failure Cause probability and a causal connection strength along the failure path to an End-effect. | Criticality editor, Failure Concepts (MADE & RAM Modules) |
| Off-line | - | - | Typically laboratory instruments designed to be in an environmentally controlled location, used by trained personnel. These instruments are used when a large variety of test methods are required and result turnaround time is not critical. These instruments offer greater versatility of analysis methods compared to "In-Line" sensors but required manpower to perform analyses and retrieve resilts. This method of sensing has the longest results turnaround time. | Component Test Point, Sensor Allocation (PHM Module) |
| On-line | - | - | Fully automated systems used to closely monitor concentrations of analytes critical to the production process. On-line sensors are able to control external devices such as pumps or valves as part of their analysis sequences. As the results are exported automatically the analyser can also control external devices based on their analysis results e.g. turning on/off dosing pumps. This method of sensing employs a sensor which is plumbed directly into the sample stream with one instrument able to monitor multiple samples. | Component Test Point, Sensor Allocation (PHM Module) |
| Operating Context Availability | A o | Operational Availability | The period of time a system maintains its operational capability based on probabilistic values derived from system reliability. Availability calculations are based on parameters including delay time, turnaround time and spares on hand. | FCM Reliability, Spares Optimisation (RAM Modules) |
| Operating Context Reliability | - | Operational Reliability | The reliability of a system (represented as a decimal fraction) taking into account non-system failures (Is Failure?). This term was introduced exclusively for a spares optimisation tool. | FCM Reliability, Spares Optimisation (RAM Modules) |
| Operational Condition | - | - | A description of the expected state (weight, speed, accelerations, altitude, attitude, etc) of the system. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Operational Event | - | - | A significant modification in the Operational Conditions of a Mission Phase or Specialized Phase in reaction to a distinct occurrence (which may or may not result from failures). | Mission Profile Definitions, Functional Diagram (All Modules) |
| Overall Effect | - | - | The overall Failure Effect resulting from the Failure Mode with respect to a Failure Condition. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Pair | - | [Image: pair.png] | The combination of two parts, created by assigning a physical connection between them. A pair possesses functions and failures, and may be connected up to the functional failure mode of a component. | Project Explorer, System Model (MADE & RAM Modules) |
| Parallel Group | - | - | A parallel group indicates a redundant system. As long as one item within the parallel group is operational the system is regarded as operating. | Reliability/Availability Block Diagram (MADE & RAM Modules) |
| Part | - | [Image: partLarge.png] | The lowest possible level of hierarchy in the MADE system model. A part on its own does not perform a function however its physical characteristics and environmental factors can be defined. | Project Explorer, System Model (MADE & RAM Modules) |
| Part-level model | - | Hardware model | The representation of a system in which the system elements are defined in primarily in terms of the equipment used and their physical properties. | System Model (MADE & RAM Modules) |
| Perturb Response Margin | - | - | Perturb Response Margin is the threshold applied to determine whether a component response (transient, steady state) has deviated from nominal. The margin is calculated as a percentage of the nominal response value at the same time step. | Propagation Table, Response Simulation, System Model (MADE & RAM Modules) |
| Perturbation | - | Deviation | A deviation of a system, moving object, or process from its regular or normal state or path, caused by an outside influence. In MADE this refers to a deviation (high or low) of a flow response from its nominal condition. | Propagation Table, Response Simulation, System Model (MADE & RAM Modules) |
| Polarity | - | - | Defines whether an increase in cause increases the effect (positive) or decreases the effect (negative). | Functions Editor, Failure Diagram (MADE & RAM Modules) |
| Positive Predictive Value | PPV | Precision | Proportion of identified failure modes that are truly failure modes. The probability a failure mode will be present when the sensor signals that a failure mode is present. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Power Bond Modelling | - | Bond Modelling | An energy model of a dynamic system that represents bi-directional exchange of energy. | MADE Module |
| Probability of Detection | POD | Sensitivity, True Positive Rate, Recall | Proportion of positives that are correctly identified. The probability that a failure mode (high or low flow response) when present, will be correctly identified as such. | PHM Module |
| Prognostics and Health Management | PHM | - | Prognostics and Health Management is the discipline of linking the monitoring of failure mechanisms to the life-cycle management of the system in order to minimise system down-time and supportability costs. | PHM Module |
| Progression Rate | Pr | - | A fuzzy value that defines how quickly a mechanism generates a fault. The progression rate is assigned to the causal connection between mechanism and fault. | Failure Diagram (MADE & RAM Modules) |
| Propagation Table | - | Failure Propagation Table | The Propagation Table shows the flow responses of items (table columns) in the system that occur due to each functional failure (table rows). | Propagation Table Functional/Simulation (MADE & RAM Modules) |
| Redundancy | - | - | The existence of more than one means for accomplishing a given function where each means need not necessarily be identical. Redundancy can be either active (items activated only on the failure of the primary item(s) performing the function) or standby (items running only when required). | Reliability/Availability Block Diagram, Item Properties>Compensating Provisions, Reliability-Centered Maintenance (RAM Modules) |
| Redundancy Group, K/N | - | - | In a K/N redundancy group it is assumed all items are operating. The group as a whole is made up of N number of items and will be considered functional as long as K number of items have not failed. When the number of non-failed items drops below K the group is considered failed. | Reliability Block Diagrams (RAM Module) |
| Reliability | R(t) | - | (a)The duration of probability of failure-free performance under stated conditions. (b)The probability that an item can perform its intended function for a specified interval under stated conditions. | Reliability/Availability Block Diagram, Reliability-Centered Maintenance, Maintenance Cost Estimates (RAM Module) |
| Reliability Allocation | - | - | A method of apportioning a system target reliability amongst system, sub-system and component items. | Reliability Allocation editor (RAM Module) |
| Reliability Block Diagram | RBD | - | A RBD maps the way items contribute to the operation of a system and calculates the reliability of the whole system using the reliabilities of constituent items and reliability groupings. | Reliability Block Diagram (RAM Module) |
| Resistance Factor | - | - | When a resistor is perturbed, the value at time of the perturbation is added to or subtracted by this factor, depending on the direction of the perturbation (i.e. up or down). | Simulation Analysis (MADE & RAM Modules) |
| Risk Priority Category | RPC | - | The Risk Priority Category uses the same method as Risk Priority Number but instead of providing a crisp number as an output, a fuzzy category is used. The Risk Priority Category will appear as Very Low, Low, Moderate, High or Very High based on the RPN. | Criticality Analysis, Critical Item Analysis, Chart Analysis, Sensor Analysis (MADE & RAM Modules) |
| Risk Priority Number | RPN | - | Risk Priority Number is a criticality method that is typically used in the commercial sector for evaluating the risk or criticality of a failure mode. The RPN uses three variables Occurrence, Severity and Detectability (Difficulty of Detection in the MADE taxonomy) to determine the Risk Priority Number on a scale between 1 and 10. The Risk Priority Number is a multiplication of the above variables and may range from 1 to 1000. | Criticality Analysis, Critical Item Analysis, Chart Analysis, Sensor Analysis (MADE & RAM Modules) |
| Safety Criteria | - | - | A description of benchmark to ensure safety of the system. | Functional Diagram (All Modules), Functional Hazard Assessment (Project Preferences) |
| Safety & Risk Assessment | SRA | - | A module for conducting safety and criticality analyses to identify risks associated with identifying failure concepts e.g. functional failure mode of an item. | Sensor Sets (PHM Module) |
| Scheduled Maintenance | - | Preventative Maintenance | A maintenance approach conducted at a specific and regular time interval. | Maintenance Actions, RCM (RAM Module) |
| Sensed Test Points | - | FDI Coverage | The proportion of failure modes that have been selected for monitoring that can be detected and identified by the sensor set under consideration. | Sensor Sets (PHM Module) |
| Sensitivity | POD | Probability of Detection | Proportion of positives that are correctly identified. The probability that a failure mode (high or low flow response) when present, will be correctly identified as such. This is calculated as the True Positives as a proportion of all positive conditions. | Sensor Analysis, Sensor Parameters (PHM Module) |
| Series Group | - | - | A series group indicates no redundancy. If an entire system is in series, any failure will stop the operation of the system. | Reliability/Availability Block Diagram (RAM Module) |
| Severity | S | - | The consequences of a failure mode, defined in terms of either a crisp (1 to 10 ranking) or fuzzy (linguistic e.g. high, very high etc.) value. Severity considers the worst potential consequence of a failure, determined by the degree of injury, property damage, or system damage at the level of indenture at which it occurs. | Criticality Editor (MADE & RAM Modules) |
| Severity, Apparent | App. S | - | The severity of the end-effect considering the relative rate at which the initial failure develops and progresses to the end-effect. It is calculated as a Fuzzy combination of severity of end-effect and rate at which the physical mechanism of failure occurred (progression rate). | Criticality Editor (MADE & RAM Modules) |
| Shop Replaceable Unit | SRU | - | A unit or essential support item for which one or more maintenance actions cannot be performed in the field, forcing the system to return to a maintenance facility. | System Module (MADE & RAM Modules) |
| Slope | - | Shape Parameter, β | The slope of the line in the probability plot. It determines which family of Weibull distributions provide the best fit for the reliability data provided. As on the defining parameters for a Weibull distribution, it indicates which class of failure is present (infant mortality, random failures, wear out failures). | Reliability Editor, RBD Analysis, Maintenance Cost Estimates (MADE & RAM Modules) |
| Software Control | - | - | For MIL-STD-882E, this describes the degree of control that software exercises over hardware and is used to derive a software control category. | Criticality Editor (MADE & RAM Modules) |
| Software Control Category | - | - | An assignment of the degree of autonomy, command and control authority, and redundant fault tolerance of a software function in context with its system behaviour. Indicates the degree of control that software exercises over hardware. | Criticality Editor (MADE & RAM Modules) |
| Software Criticality Index | - | - | The Sofware Criticality Index (SwCI) assigns a Level of Rigor and a corresponding Task to define each cell in the Software Safety Criticality Matrix (SSCM). The SSCM compares Software Control Category against Severity to associate both SwCI and Risk Level of a given potential hazardous outcome. | Criticality Editor (MADE & RAM Modules) |
| Spares Cost Factor | Ns | - | The factor to multiply acquisition cost (Ca) to determine the cost of spares. This value is set to 0 for repair-based maintenance types. | Maintenance Cost Estimates (RAM Module) |
| Spares on Hand | - | - | Number of replacement spares available for the system, component or part. | Reliability Editor (RAM Module) |
| Specialized Phase | - | - | A phase of mission that is not part of typical expected operation but that might be experienced regularly by a particular system in the fleet or by a particular operator. | Mission Profile Definitions, Functional Diagram (All Modules) |
| Specificity | - | True Negative Rate | Proportion of negatives that are correctly identified. The probability that a nominal response when present, will be correctly identified as such. | Sensor Parameters (PHM Module) |
| Standard Deviation (Characteristic Life) | - | - | A value that determines the amount of variation from the average characteristic life. This value is only used for Monte Carlo analyses. | Reliability Editor, Monte Carlo (MADE & RAM Modules) |
| Standard Deviation (Failure Rate) | - | - | A value that determines the amount of variation from the average failure rate. This value is only used for Monte Carlo analyses. | Reliability Editor, Monte Carlo (MADE & RAM Modules) |
| Standby Redundancy Group | - | - | Standby redundancy assumes a set number of items (K) are required to be functional for the group (made up of N items) to be considered non-failed. In standby redundancy items are assumed not to be operational until required and as such do not accumulate life until operational. | Reliability/Availability Block Diagram (RAM Module) |
| Substantiation Action | - | - | All of the activities performed to produce evidence that an FHA is complete and correct. | Functional Diagram (All Modules), Functional Hazard Assessment (Project Preferences) |
| Subsystem | - | [Image: subsystemlarge.png] | A grouping of components, sub-systems or parts that work together to fulfil a common function. | Project Explorer, System Model (All Module) |
| Symptom | - | - | A detectable manifestation of a failure, or fault. A symptom is an indication that a fault or failure has occurred, and may be used in monitoring applications. | Failure Diagram, Reliability-centred Maintenance, PHM (All Modules) |
| System | - | [Image: assembly.png] | A grouping of sub-systems, components and parts which interact to fulfil a common function. A system is the highest level of indenture within a MADE project. | Project Explorer, System Model (All Modules) |
| Target Reliability | - | - | A value of reliability that a system must meet. This value is used to apportion reliability targets for components in a system during reliability allocation. | Reliability Allocation Editor, Reliability Allocation Analysis (MADE & RAM Modules) |
| Test Point | - | Built-In-Test | Locations in the system where sensor equipment is used to detect failure modes within a component by calculated probability of detection. | System Model (PHM Module) |
| Threshold Reliability | - | - | The value that corresponds to a particular reliability value that must be met. This value is used to determine the MTBF for items with an age related dominant failure mode. | Maintenance Cost Estimates (MADE & RAM Modules) |
| Transient Load | - | - | A Transient Load refers to any loading that occurs in an irregular cycle, or does not follow a continuous behaviour. | System Model (MADE Module) |
| Transformer / Gyrator Factor | - | - | When a transformer or gyrator is perturbed, the value at time of the perturbation is multiplied or divided by this factor, depending on the direction of the perturbation (i.e. up or down). | Simulation Analysis (MADE & RAM Modules) |
| Trivalent | - | - | A linear graph that can produce three different outputs, -1 (low), 0(nominal) and 1(high). | Fuzzy Cognitive Maps (MADE & RAM Modules) |
| Trivalent Sigmoid | - | - | A sigmoid is a mathematical function that relates to an "S" shaped curve (sigmoid curve). A trivalent sigmoid is capable of providing outputs within the range of -1(low) to 1(high). | Fuzzy Cognitive Maps (MADE & RAM Modules) |
| True Positive | TP | - | Sensor correctly signalling (predicting) a failure mode when a failure mode is present. A failure mode, being a non-nominal (high or low) flow property response. | Component Test Point, Sensor Set Groups (PHM Module) |
| True Negative | TN | - | Sensor correctly signalling no failure mode when no failure mode is present. No failure mode, being a nominal flow property response. | Component Test Point, Sensor Set Groups (PHM Module) |
| Turn Around Time | - | - | The period of time required to fully shutdown and then restart system to operational state due to planned/scheduled downtime. | Reliability Editor (RAM Module) |
| Useful Life | - | - | The age at which there is a rapid increase in the probability of failure (not to be confused with 'average life'). | Maintenance Cost Estimates, Reliability-Centered Maintenance (MADE & RAM Modules) |
| Weighted Allocation | - | - | Weighted Allocation Method calculates Reliability Allocation based on a weighted distribution amongst items in a level of indenture to satisfy the Target Reliability of the parent item. Calculations used depend on the type of RBD groups present. | Reliability Allocation editor (RAM Module) |
Source: Local MADE 3.9.1 installation: com.phm.made.help.plugin/documents/help/html/MADeHelp/01-Glossary.html · retrieved 2026-07-09