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**M**\\ | **M**\\ | ||
• [[en:infra-convert:user:terms#Measurement (sizes-)]]\\ | • [[en:infra-convert:user:terms#Measurement (sizes-)]]\\ | ||
+ | **N**\\ | ||
+ | • [[en:infra-convert:user:terms#Numerical precision]]\\ | ||
**P**\\ | **P**\\ | ||
• [[en:infra-convert:user:terms#Project]]\\ | • [[en:infra-convert:user:terms#Project]]\\ | ||
**S**\\ | **S**\\ | ||
+ | • [[en:infra-convert:user:terms#Simplified indications]]\\ | ||
• [[en:infra-convert:user:terms#Specification operators and modifiers (ISO GPS)]]\\ | • [[en:infra-convert:user:terms#Specification operators and modifiers (ISO GPS)]]\\ | ||
• [[en:infra-convert:user:terms#Stamp/stamps]]\\ | • [[en:infra-convert:user:terms#Stamp/stamps]]\\ | ||
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^ ::: ^ Percent*¹ | % | DIN 5466:1983-02 | Percent | | ^ ::: ^ Percent*¹ | % | DIN 5466:1983-02 | Percent | | ||
^ ::: ^ Mol*³ | mol | DIN 1301-1:2010-10 | Mol | | ^ ::: ^ Mol*³ | mol | DIN 1301-1:2010-10 | Mol | | ||
- | | NIST-19: National Institute of Standards and Technology, Gaithersburg, Maryland, USA: NIST Handbook 44 : Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices (Appendix C. General Tables of Units of Measurement) 2019.\\ *¹ Available from program version 1.2.0.23\\ *² Available from program version 1.3.9.5\\ *³ Available from program version 1.3.9.7 ||||| | + | | NIST-19: National Institute of Standards and Technology, Gaithersburg, Maryland, USA: NIST Handbook 44 : Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices (Appendix C. General Tables of Units of Measurement) 2019.\\ *¹ Available from program version 1.2.0.23\\ *² Available from program version 1.3.9.5\\ *³ Available from program version 1.3.9.8 ||||| |
+ | \\ | ||
+ | ---- | ||
+ | |||
+ | \\ | ||
+ | |||
+ | ==== Numerical precision ==== | ||
+ | |||
+ | The numerical precision is relevant for the representation of numerical values. If a technical fact is described with numerical values, usually in the form of physical quantities or →[[en:infra-convert:user:terms#measurement_sizes|measurement sizes]], the | ||
+ | accuracy of the displayed number should be in the same order of magnitude as the inaccuracy of the measure itself. | ||
+ | |||
+ | For example, the maximum inaccuracy range of the value 23, if no further information is available, is 22.5 to <23.5. Finally, the value may have resulted from a rounding operation. The last significant digit, here the "3", is the digit that was rounded or may have been rounded. | ||
+ | |||
+ | |< 100% 15% 15% 30% 25% 15% >| | ||
+ | ^ Value ^ Number of relevant digits ^ Rounding range (absolute inaccuracy range) ^ Size of the absolute inaccuracy range ^ Size of relative inaccuracy ^ | ||
+ | | 2**3** | 2 | 22,5 to <23,5 | 1 | 4,35 % | | ||
+ | | 2,**3** | 2 | 2,25 to <2,35 | 0,1 | 4,35 % | | ||
+ | | 23,**0** | 3 | 22,95 to <23,05 | 0,1 | 0,435 % | | ||
+ | | 2**3**00 | 2 | 2250 to <2350 | 100 | 4,35 % | | ||
+ | | 0,00023**0** | 3 | 0,0002295 to <0,0002305 | 0,000001 | 0,435 % | | ||
+ | |||
+ | The number of significant or relevant digits in a decimal number can be identified as follows (see also "DIN EN ISO 80000-1:2013-08, Chapter 7.3.4 Deviation and uncertainty"): | ||
+ | |||
+ | - The number is viewed from left to right. The first non-zero digit is the first relevant digit. | ||
+ | - Following zeros are also relevant, especially if they are to the right of the decimal point. | ||
+ | - Zeros to the left of the comma are only relevant if at least one other digit, including zero, follows to the right of the comma. | ||
+ | |||
+ | The numerical accuracy common in technology ("slide rule accuracy") is achieved by rounding a value so that three significant digits remain. Unless the first significant digit is a one, four significant digits should remain. | ||
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Even if it is technically possible, a project should always only refer to an object that is subject to a test and, if necessary, follow-up tests. This may be, for example, the initial sampling of a product and its subsequent re-sampling (first-piece approvals, requalifications). | Even if it is technically possible, a project should always only refer to an object that is subject to a test and, if necessary, follow-up tests. This may be, for example, the initial sampling of a product and its subsequent re-sampling (first-piece approvals, requalifications). | ||
+ | |||
+ | \\ | ||
+ | |||
+ | ---- | ||
+ | |||
+ | \\ | ||
+ | |||
+ | ==== Simplified indications ==== | ||
+ | |||
+ | By using a **simplified specification**, requirements for a geometry element are specified in simplified form and explained elsewhere in the drawing, for example next to a view or near the title block. This type of specification can be useful if there is not enough space available in a view or if a specification applies to several separate geometry elements and is specified more than once. | ||
+ | |||
+ | The following example shows the principle for surface specifications and geometric tolerance specifications. | ||
+ | |||
+ | {{ :en:infra-convert:user:terms:vereinfachte_angaben.png?nolink&600 |}} | ||
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