What is t minus mean code#
What is t minus mean plus#

The date is set relative to the event that is at the end, and you schedule the tasks based on the lead time for the event. If that time is 45 seconds away, it is said to be вЂT-minus 45 seconds and counting. A T-minus list is a checklist of items with a date attached.

What is t minus mean code#

(Similarly, external features use a lowercase letter, so a corresponding hole might be 16d8, which corresponds to 15.923 to 15.950 mm.)ДЇor more information on the code letters and numbers for this ISO usage, consult a MachineryвЂ™s Handbook or the ANSI standard for вЂњPreferred Metric Limits and Fits,вЂќ ANSI B4.2-1978. In a 2010 Mission News post on the NASA website for the EPOXI Mission, Jet Propulsion Laboratory media relations specialist DC Agle explained that the t in t-minus stands for time: When a rocket is getting ready for liftoff, it will be lifting off at a specific time.

What is t minus mean plus#

The вЂњ16D8вЂќ is usually not understood in American design usage, so if a design is being converted from another country to an American program, the engineer usually translates it into an odd-looking вЂњplus/plusвЂќ tolerance: The abbreviations T+1, T+2, and T+3 refer to the settlement dates of security transactions that occur on a transaction date plus one day, plus two days, and plus three. For example, 16D8 corresponds to a hole with a nominal size of 16 mm, but with actual limits of 16.050 to 16.077 mm (I had to look this up in a table!). A nominal size would be given, along with a letter and number.

In the metric system, an entire method of coding different limits and fits has been developed. In this way we can say that the pin and hole each have a nominal size of 1.250 inches, but the respective tolerances will ensure that there is always a little looseness (clearance fit). So if the example given above is a hole, then a pin in the mating part may be dimensioned with a minus/minus tolerance. Depending on the assembly, they may want a press fit, transition fit, or clearance fit. The most likely answer is because there is some desired fit with a mating feature.

(one-sample t-test against a test mean of 0: control 1 (6j2): t 4.87. The real problem is that, with a casual glance, you might not realize that a part made at the вЂњnominalвЂќ size of 1.25 is a bad part! (The size limits are 1.252 вЂ“ 1.255.) So the obvious question is: Why did the engineer (or designer) choose this odd method of expressing a tolerance? Mean 6 standard error difference (personal poor minus personal rich) in the. But IвЂ™ve seen examples such as a hole dimensioned with: For a two-sample (independent) t-test, statistics programs usually display the sample means of each group, m A and m B, and the. HereвЂ™s an interesting tolerance question: Have you ever seen a plus/plus tolerance? (or minus/minus?) The ASME standard does not mention this, so a purist would say that it is illegal (see paragraphs 2.2 and 2.3 of the Y14.5 standard). What to report What a statistics program gives you: For a one-sample t-test, statistics programs produce an estimate, m (the sample mean), of the population mean, along with the statistic t, together with an associated degrees-of-freedom (df), and the statistic p.