Template:Time-to-failure data - Revision history

Richard House: Redirected page to RGA Data Types

2012-08-24T01:05:34Z

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	~~===Time-to-Failure Data===~~		#REDIRECT [[RGA_Data_Types]]
	Time-to-failure (continuous) data is the most commonly observed type of reliability growth data. It involves recording the times-to-failure for the unit(s) under test. Time-to-failure data can be applied to a single unit or system or to multiple units or systems. There are multiple data entry schemes for this data type and each is presented next.
	~~{{failure times data}}~~


	~~{{grouped failure times}}~~

	~~{{multiple systems (known operating times)}}~~

	~~{{multiple systems (concurrent operating times)}}~~

	~~{{multiple systems (concurrent operating times)-using dates}}~~

	~~{{multiple systems with event codes}}~~

	~~====Models for Time-to-Failure (Continuous) Data====~~
	~~The following models can be used to analyze time-to-failure (continuous) data sets. Models and examples using the different data types are discussed in later chapters.~~

	~~<br>~~
	~~:1)~~ [[~~RGA Chapter 4\|Duane~~]]

	~~:2) [[RGA Chapter 5\|Crow-AMSAA (NHPP)]]~~

	~~:3) [[RGA Chapter 9\|Crow Extended]]~~

	~~:4) [[RGA Chapter 10\|Crow Extended - Continuous Evaluation]]~~
	~~<br>~~

Athanasios Gerokostopoulos: /* Models for Time-to-Failure (Continuous) Data */

2012-06-06T20:06:10Z

Models for Time-to-Failure (Continuous) Data

← Older revision		Revision as of 20:06, 6 June 2012
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	<br>		<br>
	:1) [[RGA Chapter 4\|Duane]]		:1) [[RGA Chapter 4\|Duane]]
	~~<br>~~
	:2) [[RGA Chapter 5\|Crow-AMSAA (NHPP)]]		:2) [[RGA Chapter 5\|Crow-AMSAA (NHPP)]]
	~~<br>~~
	:3) [[RGA Chapter 9\|Crow Extended]]		:3) [[RGA Chapter 9\|Crow Extended]]
	~~<br>~~
	:4) [[RGA Chapter 10\|Crow Extended - Continuous Evaluation]]		:4) [[RGA Chapter 10\|Crow Extended - Continuous Evaluation]]
	<br>		<br>

Athanasios Gerokostopoulos: /* Models for Time-to-Failure (Continuous) Data */

2012-06-06T20:05:43Z

Models for Time-to-Failure (Continuous) Data

← Older revision		Revision as of 20:05, 6 June 2012
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	====Models for Time-to-Failure (Continuous) Data====		====Models for Time-to-Failure (Continuous) Data====
	The following models can be used to analyze time-to-failure (continuous) data sets. Models and examples using the different data types are discussed in later chapters.		The following models can be used to analyze time-to-failure (continuous) data sets. Models and examples using the different data types are discussed in later chapters.

	<br>		<br>
	:1) ~~Duane (~~Chapter 4)		:1) [[RGA Chapter 4\|Duane]]
	<br>		<br>
	:2) Crow-AMSAA (NHPP) ~~(Chapter 5)~~		:2) [[RGA Chapter 5\|Crow-AMSAA (NHPP)]]
	<br>		<br>
	:3) Crow Extended ~~(Chapter 9)~~		:3) [[RGA Chapter 9\|Crow Extended]]
	<br>		<br>
	:4) Crow Extended - Continuous Evaluation ~~(Chapter 10)~~		:4) [[RGA Chapter 10\|Crow Extended - Continuous Evaluation]]
	<br>		<br>

Nicolette Young at 18:04, 5 January 2012

2012-01-05T18:04:30Z

← Older revision		Revision as of 18:04, 5 January 2012
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	{{multiple systems with event codes}}		{{multiple systems with event codes}}

	{{models ~~for~~ time-to-failure (continuous) data}}		====Models for Time-to-Failure (Continuous) Data====
			The following models can be used to analyze time-to-failure (continuous) data sets. Models and examples using the different data types are discussed in later chapters.
			<br>
			:1) Duane (Chapter 4)
			<br>
			:2) Crow-AMSAA (NHPP) (Chapter 5)
			<br>
			:3) Crow Extended (Chapter 9)
			<br>
			:4) Crow Extended - Continuous Evaluation (Chapter 10)
			<br>

Nicolette Young: /* Models for Time-to-Failure (Continuous) Data */

2012-01-05T18:03:52Z

Models for Time-to-Failure (Continuous) Data

← Older revision		Revision as of 18:03, 5 January 2012
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	{{multiple systems with event codes}}		{{multiple systems with event codes}}

	~~====Models~~ for ~~Time-to-Failure (Continuous) Data====~~		{{models for time-to-failure (continuous) data}}
	~~The following models can be used to analyze~~ time-to-failure (continuous) data ~~sets. Models and examples using the different data types are discussed in later chapters.~~
	~~<br>~~
	~~:1) Duane (Chapter 4)~~
	~~<br>~~
	~~:2) Crow-AMSAA (NHPP) (Chapter 5)~~
	~~<br>~~
	~~:3) Crow Extended (Chapter 9)~~
	~~<br>~~
	~~:4) Crow Extended - Continuous Evaluation (Chapter 10)~~
	~~<br>~~

Nicolette Young: /* Multiple Systems with Event Codes */

2012-01-05T18:03:19Z

Multiple Systems with Event Codes

← Older revision		Revision as of 18:03, 5 January 2012
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	{{multiple systems (concurrent operating times)-using dates}}		{{multiple systems (concurrent operating times)-using dates}}

	~~====Multiple Systems with Event Codes====~~		{{multiple systems with event codes}}
	The Multiple Systems with Event Codes data type is used to analyze the failure data from a reliability growth test in which a number of systems are tested concurrently and the implemented fixes are tracked during the test phase. With this data type, all of the systems ~~under test are assumed to have the same system hours at any given time. Figure Figdvancedultipleventodes shows an example of this type of data.~~

	~~<br>~~
	~~[[Image:rga3.10.png\|thumb\|center\|400px\|Advanced view for Multiple Systems~~ with ~~Event Codes]]~~

	====Models for Time-to-Failure (Continuous) Data====		====Models for Time-to-Failure (Continuous) Data====

Nicolette Young: /* Multiple Systems (Concurrent Operating Times) - Using Dates */

2012-01-05T18:02:50Z

Multiple Systems (Concurrent Operating Times) - Using Dates

← Older revision		Revision as of 18:02, 5 January 2012
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	{{multiple systems (concurrent operating times)}}		{{multiple systems (concurrent operating times)}}

	~~====Multiple Systems~~ (~~Concurrent Operating Times~~) - ~~Using Dates====~~		{{multiple systems (concurrent operating times)-using dates}}
	This is similar to the previous data type except that dates are utilized along with operating hours. This assumes noncontinuous usage and the software computes equivalent (average) usage rates. Figure fignormviewdates shows an example of this in RGA.



	~~[[Image:rga3.9.png\|thumb\|center\|400px\|Normal view for Concurrent Operating Times for Multiple Systems data with~~ dates]]

	====Multiple Systems with Event Codes====		====Multiple Systems with Event Codes====

Nicolette Young: /* Multiple Systems (Concurrent Operating Times) */

2012-01-05T18:02:12Z

Multiple Systems (Concurrent Operating Times)

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 {{multiple systems (known operating times)}}
-====Multiple Systems (Concurrent Operating Times)====
+{{multiple systems (concurrent operating times)}}
 ====Multiple Systems (Concurrent Operating Times) - Using Dates====

Nicolette Young: /* Multiple Systems (Known Operating Times) */

2012-01-05T18:01:35Z

Multiple Systems (Known Operating Times)

← Older revision		Revision as of 18:01, 5 January 2012
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	{{grouped failure times}}		{{grouped failure times}}

	~~====Multiple Systems~~ (~~Known Operating Times)====~~		{{multiple systems (known operating times)}}
	This data type is used for tests where a number of systems are tested. If a failure occurs in any system, a corrective action is taken on the failed unit and any design changes are incorporated into all test systems. Once the corrective actions have been implemented, the test is resumed. The time-to-failure for the failed system, along with the current operating times of all other systems, are recorded. The data can be cumulative or non-cumulative. Consider the following table where the Failed Unit ID column indicates which unit failed. For example, if you enter 2 into the Failed Unit ID column, this indicates that the unit in the Time Unit 2 column is the one that failed. For the units that did not fail, you must enter the operating time at the time of the other unit's failure.
	~~<br>~~
	~~<math></math>~~
	~~[[Image:rga3.6.png\|thumb\|center\|400px\|Multiple Systems(Known Operating Times~~) ~~data.]]~~
	~~<br>~~
	~~<br>~~
	In this table, two units are undergoing testing and the units do not accumulate age at the same rate. At 10 hours into the test, unit 1 fails and corrective action is taken on both units 1 and 2. By this time, both units have accumulated 10 hours of operation. At 17 hours, unit 2 fails and corrective action is again implemented on both units; however, unit 1 has accumulated 5 hours and unit 2 has accumulated 7 hours since the last event, and so forth.

	====Multiple Systems (Concurrent Operating Times)====		====Multiple Systems (Concurrent Operating Times)====

Nicolette Young: /* Grouped Failure Times */

2012-01-05T18:00:55Z

Grouped Failure Times

← Older revision		Revision as of 18:00, 5 January 2012
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	~~====Grouped Failure Times====~~		{{grouped failure times}}
	~~This data type is used for tests where the exact~~ failure times are unknown and only the number of failures within a time interval are recorded (e.g. inspection data). For a single system, multiple failures can occur before the operator stops the test. In this case, X number of failures are found after Y hours of test time. Failures X <math>_{1}</math> , X <math>_{2}~~</math> , X <math>_{3~~}~~</math> , etc. could have occurred at any time period up to the termination time, thus exact times for each failure are not available. This is commonly called interval or grouped data.~~

	When multiple units are tested, the units are inspected at predetermined time intervals and the number of failed units is recorded. When entering the time at which the failures occurred for grouped data, the time is equal to the total accumulated test time for all of the units being tested. The number of failed units is simply equal to the number of failures that occurred during the current interval. Figure grpcum1 shows an example of data entry for grouped data.

	~~<br>~~
	~~[[Image:rga3.5.png\|thumb\|center\|400px\|Grouped Failure Times data]]~~

	====Multiple Systems (Known Operating Times)====		====Multiple Systems (Known Operating Times)====