结合最近大家的提问和发的讨论等帖子，觉得大家需要明确的术语概念
我觉得有部分人对结构可靠性和设计方法的一些术语还不是太清楚，所以查阅收集了一些内容和标准，供大家参考。1. 可靠性 reliability
结构在规定的时间内,在规定的条件下,完成预定功能的能力,它包括结构的安全性,适用性和耐久性,当以概率来度量时,称可靠度.
2. 安全性 safety
结构在正常施工和正常使用条件下,承受可能出现的各种作用的能力,以及在偶然事件发生时和发生后,仍保持必要的整体稳定性的能力.
3. 适用性 serviceability
结构在正常使用条件下,满足预定使用要求的能力.
4. 耐久性 durability
结构在正常维护条件下,随时间变化而仍能满足预定功能要求的能力.
5. 基本变量 basic variable
影响结构可靠度的各主要变量,它们一般是随机变量.
6. 设计基准期 design reference period
进行结构可靠性分析时,考虑各项基本变量与时间关系所取用的基准时间.
7. 可靠概率 probability of survival
结构或构件能完成预定功能的概率.
8. 失效概率 probability of failure
结构或构件不能完成预定功能的概率.
9. 可靠指标 reliability index
度量结构可靠性的一种数量指标.它是标准正态分布反函数可在可靠概率处的函数值,并与失效概率在数值上有一一对应的关系.
10. 校准法 calibration
通过对现存结构或构件安全系数的反演分析来确定设计时采用的结构或构件可靠指标的方法.
11. 定值设计法 deterministic method
基本变量作为非随机变量的设计计算方法,其中,采用以概率理论为基础所确定的失效概率来度量结构的可靠性.
12. 概率设计法 probabilistic method
基本变量作为随机变量的设计计算方法.其中,采用以概率理论为基础所确定的失效概率来度量结构的可靠性.
13. 容许应力设计法 permissible (allowable) stresses method
以结构构件截面计算应力不大于规范规定的材料容许应力的原则,进行结构构件设计计算方法.
14. 破坏强度设计法 ultimate strength method
考虑结构材料破坏阶段的工作状态进行结构构件设计计算的方法,又名极限设计法,苛载系数设计法,破损阶段设计法,极限荷载设计法.
15. 极限状态设计法 limit states method
以防止结构或构件达到某种功能要求的极限状态作为依据的结构设计计算方法.
16. 极限状态 limit states
结构或构件能够满足设计规定的某一功能要求的临界状态,超过这一状态,结构或构件 便不再满足对该功能的要求.
17. 极限状态方程 limit state equation
当结构或构件处于极限状态时,各有关基本变量的关系式.
18. 承载能力极限状态 ultimate limit states
结构或构件达到最大承载能力,或达到不适于继续承载的变形的极限状态.
19. 正常使用极限状态 serviceability limit states
结构或构件达到使用功能上允许的某一限值的极限状态.
20. 分项系数 partial safety factor
用极限状态法设计时,为了保证所设计的结构或构件具有规定的可靠,而在计算模式中采用的系数,分为作用分项系数和抗力分项系数两类.
21. 设计状况 design situation
以不同的设计要求,区别对待结构在设计基准期中处于不同条件下所受到的影响,作为结构设计选定体系,,设计值,可靠性要求等的依据.
22. 持久状况 persistent situation
出现的持续时间长,几乎与结构设计基准期相同的设计状况.
23. 短暂状况 transient situation
出现的持续时间较短,而出现概率高的设计状况.
24. 偶然状况 accidental situation
偶然事件发生时或发生后,其出现的持续时间短,而出现概率低的设计状况.
稳定性 stability
结构或构件保持稳定状态的能力。
[转帖]可靠性术语大全Reliability Glossary List
转至http://www.6sq.net/art/html/43/52950.html可靠性术语Reliability Glossary (Alphabetical Listing)
[中英文，某些常用的翻译了一下。更多的需要自己来啦]
The following glossary contains brief definitions of terms frequently used in reliability engineering and life data analysis. The purpose of these entries is to provide a quick explanation of the terms in question, not to provide extensive explanations or mathematical derivations. For those desiring such detailed descriptions, links have been provided when possible for more extensive coverage elsewhere in ReliaSoft's reliability engineering knowledge base.
A
Accelerated life testing
A testing strategy whereby units are tested at stress levels higher than use stress in order to facilitate failures in a timely manner. The results of these tests are then analyzed in such a manner so that a profile of the failure behavior of the products at the use stresses can be determined based on the behavior of the products at the accelerated stresses.
加速试验
为缩短观测产品应力响应所需要持续时间或放大给定持续时间内的响应，在不改变基本的故障模式和失效机理或它们的相对主次关系的前提下，施加的应力水平选取超过规定的基准条件的一种试验。
AMPM
AMPM stands for AMSAA maturity prediction model. This is an enhanced reliability growth model that allows the user to predict failure rates in future stages of development. This model allows the user to assess the effectiveness of proposed and implemented fixes in order to determine the future failure rate.
AMSAA model
AMSAA stands for Army Material Systems Analysis Activity. This is a reliability growth model that uses a relationship between cumulative test time and cumulative failures to develop a reliability growth model.
ANOVA
ANOVA stands for analysis of variance, a method by which the source of variability is identified. This method is widely used in industry to help identify the source of potential problems in the production process, and identify whether variation in measured output values is due to variability between various manufacturing processes, or within them. By varying the factors in a predetermined pattern and analyzing the output, one can use statistical techniques to make an accurate assessment as to the cause of variation in a manufacturing process.
Arrhenius model
A model used in accelerated life testing to establish a relationship between absolute temperature and reliability. It was originally developed by Swedish chemist Svante Arrhenius to define the relationship between temperature and the rates of chemical reaction.
Availability
Availability is the probability that an item will be able to function (i.e. not failed or undergoing repair) when called upon to do so. This measure takes into account an item’s reliability (how quickly it fails) and its maintainability (how quickly it can be repaired
可用性
在要求的外部资源得到保证的前提下，产品在规定的条件下和规定的时刻或时间区间内处于可执行规定功能状态的能力。它是产品可靠性、维修性和维修保障想的综合反映。
B
BX life
The time at which X% of the units in a population will have failed. For example, if an item has a B10 life of 100 hours, that means that 10% of the population will have failed by 100 hours of operation.
Block diagram
A diagram that represents how the components, represented by "blocks," are arranged and related reliability-wise in a larger system. This is often but not necessarily the same as the way that the components are physically related. This is also called a Reliability Block Diagram or RBD.
C
Censored data
Data in which not all of the data points represent failures, i.e. there may be operation times for units that have not failed. Censoring schemes include right-censoring, left-censoring and interval censoring.
Competing failure modes
A model whereby items that fail due to more than one failure mode can be represented as a series reliability system with each block representing a failure mode. The failure modes are considered to be "competing" amongst each other to see which one will cause the item to fail.
Complete data
A data set consisting only of failure times.
Complex system
A block diagram that cannot be reduced to series and/or parallel systems.
Confidence bounds
A measure of the precision of a statistical estimate. This is represented by a range of values that the particular estimate should fall between a specified percentage of the time. For example, if we perform ten different reliability tests for our items and analyze the results, we will obtain slightly different parameters for the distribution each time, and thus slightly different reliability results. However, by employing confidence bounds, we obtain a range within which these reliability values are likely to occur a certain percentage of the time. This helps us gauge the utility of the data and the accuracy of the resulting estimates.
Contour plot
A graphical representation of the possible solutions to the likelihood ratio equation. This is employed to determine confidence bounds as well as comparisons between two different data sets.
Cumulative damage model
An accelerated life testing model used to model accelerated tests where the stress levels vary with time.
Cumulative density function (cdf)
A function obtained by integrating the failure distribution pdf. In life data analysis, the cdf is equivalent to the unreliability function.
D
Decomposition method
A method for determining the reliability of complex systems. The decomposition method is an application of the law of total probability, which involves choosing a "key" component and then calculating the reliability of the system twice: once as if the key component failed and once as if the key component succeeded. These two probabilities are then combined to obtain the reliability of the system, since at any given time the key component will be failed or operating.
Degradation analysis退化分析
Analysis involving the measurement and extrapolation of degradation or performance data that can be directly related to the presumed failure of the product in question. Degradation analysis allows the user to extrapolate to an assumed failure time based on the measurements of degradation or performance over time.
Down time
The amount of time a repairable unit is not operating. This can be due to being in a failed state, administrative delay, waiting for replacement parts to be shipped or undergoing active repair.
Duane model
A reliability growth model similar to the AMSAA model that uses a relationship between cumulative test time and cumulative failures to develop a reliability growth profile.
E
Event space method
A method for determining the reliability of complex systems. With the event space method, all mutually exclusive events are determined. The reliability of the system is simply the probability of the union of all mutually exclusive events that yield a system success (the unreliability is the probability of the union of all mutually exclusive events that yield a system failure
Exponential distribution
A lifetime statistical distribution that assumes a constant failure rate for the units being modeled.
Eyring model
An accelerated life testing model based on quantum mechanics for use when temperature is the accelerating factor.
F
Failure distribution
A mathematical model that describes the probability of failures occurring over time. Also known as the probability density function, this function is integrated to obtain the probability that the failure time takes a value in a given time interval. This function is the basis for other important reliability functions, including the reliability function, the failure rate function and the mean life.
Failure rate
A function that describes the number of failures that can be expected to take place over a given unit of time. The failure rate function has the units of failures per unit time among surviving units, i.e. one failure per month.
Fisher matrix
A mathematical expression that is used to determine the variability of estimated parameter values based on the variability of the data used to make the parameter estimates. It is used to determine confidence bounds when using maximum likelihood estimation (MLE) techniques.
G
Gaussian distribution
see Normal distribution
General log-linear model
An accelerated life testing model that can account for multiple non-thermal stresses as acceleration factors.
Generalized gamma distribution
While not as frequently used for modeling life data as other life distributions, the generalized gamma distribution does have the ability to mimic the attributes of other distributions such as the Weibull or lognormal, based on the values of the distribution's parameters. While the generalized gamma distribution is not often used to model life data by itself, its ability to behave like other more commonly-used life distributions is sometimes used to determine which of those life distributions should be used to model a particular set of data.
Gompertz model
A reliability growth model that models reliability values at different stages of development and produces an S-shaped reliability growth curve.
H
HALT
Highly accelerated life testing.
HASS
Highly accelerated stress screening.
Hazard rate
see Failure rate
I
Importance measure
A measure of the relative contribution of a component’s contribution to the overall system’s reliability. The importance measure of a component is equivalent to the first partial derivative of the component reliability with respect to the system reliability.
Inverse power law
An accelerated life testing model commonly used when the accelerating factor is a single, non-thermal stress.
J
K
Kaplan-Meier estimator
This is an estimator used as an alternative to the median ranks method for calculating the estimates of the unreliability for probability plotting purposes. It is also used to determine reliability estimates for nonparametric data analysis.
L
Life data analysis
The statistical analysis of failure and usage data performed in order to be able to mathematically model the reliability and failure characteristics of a product.
Life distribution
see Failure distribution
Likelihood function
A function that represents the joint probability of all the points in a data set. For complete data, the likelihood function consists of the product of the pdf for each data point; for data sets that also include suspended or censored data, the likelihood function is more complex. Maximum likelihood estimation (MLE) techniques maximize this function in order to determine the best parameter estimates.
Likelihood ratio
The ratio of a likelihood function for an unknown parameter vector to the likelihood function calculated at the estimated parameter vector. The relationship of this ratio to the chi-squared distribution can then be used to calculate confidence bounds and confidence regions.
Lloyd-Lipow model
A reliability growth model based on the number of trials and successes at each stage of product development.
Lognormal distribution
A lifetime statistical distribution that is often used to model products in which physical fatigue is the prominent contributor to the primary failure mode.
M
Maintainability
The probability that a failed unit will be repaired within a given amount of time. The term is also used to denote the discipline of studying and improving the maintainability of products, primarily by reducing the amount of time required to diagnose and repair failures.
Maximum likelihood estimation (MLE)
A method of parameter estimation involving the maximization of the likelihood equation. The best parameter estimates are obtained by determining the parameter values that maximize the value of the likelihood equation for a particular data set.
Mean Life
A reliability measure that represents the expected value of the failure times for a failure distribution, also known as the average or central life value. While this represents a useful representative value of a distribution of failure times, it is often over-used as the sole reliability metric.
Median ranks
Measures used to obtain estimates of the unreliability. Median ranks are the values that the true probability of failure should have at the jth failure out of a sample of N units, at a 50% confidence level, or the best estimate for the unreliability. This estimate is based on a solution of the binomial equation.
Mixed Weibull distribution
A variation of the Weibull distribution used to model data with distinct subpopulations that may represent different failure characteristics over the lifetime of a product. Each subpopulation has separate Weibull parameters calculated and the results are combined in a mixed Weibull distribution to represent all of the subpopulations in one function.
Modified Gompertz model
A reliability growth model that models based on a variation of the Gompertz model.
Monte Carlo simulation
A method of generating values from a known distribution for the purposes of experimentation. This is accomplished by generating uniform random variables and using them in an inverse reliability equation to produce failure times that would conform to the desired input distribution.
MTBF
MTBF stands for mean time before failure and is represented by the mean life value for a failure distribution of non-repairable units.
MTTF
MTTF stands for mean time to failure and is represented by the mean life value for a failure distribution of non-repairable units.
MTTR
MTTR stands for mean time to repair and is represented by the mean life value for a distribution of repair times. (see Maintainability.)
N
NHPP
NHPP stands for non-homogeneous Poisson process, which is a simple parametric model used to represent events with a non-constant failure recurrence rate. This type of model is often used to model reliability growth and the reliability of repairable units.
Nonparametric analysis
A method of analysis that allows the user to characterize failure data without assuming an underlying failure distribution. This avoids the potentially large errors brought about by making incorrect assumptions about the distribution. However, the confidence bounds associated with nonparametric analysis are usually much wider than those calculated via parametric analysis. Additionally, predictions outside the range of the observations are not possible.
Normal distribution
A common lifetime statistical distribution that was developed by mathematician C. F. Gauss. The distribution is a continuous, bell-shaped distribution which is symmetric about its mean and can take on values from negative infinity to positive infinity.
O
P
Path-tracing method
A method for determining the reliability of complex systems. With this method, every path from a starting point to an ending point is considered. Since system success involves having at least one path available from one end of the reliability block diagram to the other, as long as at least one path is available, the system has not failed. The reliability of the system is simply the probability of the union of these paths.
Plotting paper
see Probability plotting paper
Probability
A quantitative description of the possible likelihood of a particular event. Probability is conventionally expressed on a scale from 0 to 1, or 0% to 100%, with an unlikely event having a probability close to 0, and a very common event having a probability close to 1.
Probability density function (pdf)
A mathematical model that describes the probability of events occurring over time. This function is integrated to obtain the probability that the event time takes a value in a given time interval. In life data analysis, the event in question is a failure, and the pdf is the basis for other important reliability functions, including the reliability function, the failure rate function and the mean life.
Probability plot
A type of plot that linearizes a distribution’s cdf, allowing the user to manually plot failure time vs. estimated unreliability. Provided that the plotted points fall on a relatively straight line (thus indicating that the chosen distribution is a good fit), the parameter estimates can be obtained from scales on the plot. This is a crude, time-consuming method of fitting a distribution to failure data, but it was practically the only method available prior to the widespread use of computers.
Probability plotting paper
A specially designed type of graph paper that allows the user to plot failure time vs. unreliability as a linear function.
Proportional hazards model
An accelerated life testing model that can account for multiple non-thermal stresses as acceleration factors.
Q
Quality
A common buzzword referring to the non-quantifiable point-level excellence of a product or process. While sometimes used interchangeably with the term reliability, quality refers to the characteristics of a product at one point in time, while reliability refers to the characteristics of a product over its entire lifetime.
R
RBD
see Block diagram
Reliability
The probability of an item operating for a given amount of time without failure. More generally, reliability is the capability of parts, components, equipment, products and systems to perform their required functions for desired periods of time without failure, in specified environments and with a desired confidence.
Reliability analysis
see Life data analysis
Reliability block diagram
see Block diagram
Reliability growth
The analysis of the change in reliability over time, usually applied to products under development. Reliability growth analysis provides the means by which the reliability, mean life or failure rate is tracked over time, allowing the user to predict future reliability values based on the current rate of growth of the reliability measurement of interest.
Reliability importance
see Importance measure
Reliability life data analysis
see Life data analysis
Reliability test design
The process of designing plans for reliability testing.
Reliability testing
Testing units to failure in order to obtain raw failure time data for life data analysis.
Repair
An action that restores a failed part or component to operating condition.
Repair distribution
A mathematical model that describes the probability of repairs occurring over time.
Repairable system
A system that can be restored to operating condition after a failure by the repair or replacement of one or more components.
S
Sequential testing
A testing methodology in which test units are tested consecutively instead of simultaneously.
Spares provisioning
The stocking of spare units or components based on the anticipated number of failures for a given mission or length of operation.
SPRT
SPRT stands for sequential probability ratio test. This is a type of accept/reject sequential testing in which accept/reject boundaries are defined by the user and units are sequentially tested until either the accept boundary or the reject boundary have been reached, and a decision is made about the suitability of the units.
Statistics
The branch of mathematics that deals with the collection, organization, analysis and interpretation of data.
Stress testing
Testing units at stresses higher than what would be encountered during normal operating conditions, usually to induce failures.
Stress-strength interference
A method by which the probability of failure of an item is calculated by superimposing the distribution of the item’s strength with the distribution of the stress it will encounter during normal usage.
Suspended data
see Censored data
System reliability
The reliability of an entire system, as opposed to the reliability of its components. The system reliability is defined by the reliability of the components as well as the way the components are arranged reliability-wise.
T
Temperature-humidity model
An accelerated life testing model used when the two accelerating factors are temperature and humidity.
Temperature-non-thermal model
An accelerated life testing model used when the two accelerating factors are temperature and another non-thermal stress factor.
U
Up time
The amount of time a repairable unit is operating per design.
V
W
Warranty analysis
The analysis of warranty and return data for the purpose of determining the reliability characteristics of a product.
Weibull distribution
A statistical distribution frequently used in life data analysis. Developed by Swedish mathematician Wallodi Weibull, this distribution is widely used due to its versatility and the fact that the Weibull pdf can assume different shapes based on the parameter values.
X
Y
Z 我在文献里也看到好多可靠性术语不知道怎么翻译,比如 "deterministic finite element analysis" 翻译成数论的有限元分析?自己也没有把握,呵呵
这些专用的可靠度术语要是要对应的翻译就好了:) deterministic一般翻译成确定性吧? 原帖由 mjhzhjg 于 2006-10-4 13:21 发表
deterministic一般翻译成确定性吧?
同意楼上的看法
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