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Measurement Systems
Published in Robert B. Northrop, Introduction to Instrumentation and Measurements, 2018
The SI standard unit of length is the meter. Formerly, the meter was defined as one ten millionth of the arc distance of a meridian passing from the north pole through Paris to the equator. It was represented by an artifact consisting of a platinum–iridium bar with lines scribed on it one meter apart, kept at constant temperature at the BIPM near Paris. In 1960, the SI meter was redefined in terms of the wavelength of monochromatic light. One meter was exactly 1,650,763.73 wavelengths in vacuum of the orange radiation corresponding to the transition between the levels 2p10 and 5d5 of the Krypton-86 atom. However, this definition of the meter by wavelength assumes the permanence and invariance of the atomic energy levels, Planck’s constant, and the speed of light. These quantities are basic to the relation for the following wavelength: () λ=cv=chE=chE2−E1.
Nano-Oncotargets and Innovative Therapies
Published in Raj K. Keservani, Anil K. Sharma, Rajesh K. Kesharwani, Drug Delivery Approaches and Nanosystems, 2017
Yamuna Mohanram, Lakshmi Kiran Chelluri
Nanotechnology is a multi-interdisciplinary field of science that was developed due to the cumulative advancements in the research and development fields of material sciences, physics, chemistry, biology and electronics. This technology aims at resizing/restructuring or recreating existing materials in nanometer (nm) scales in order to bring out its maximum effective potential (Aitken et al., 2004; Schleich et al., 2014). The etiology to the term ‘nm’ traces its origin to the Greek work “nanos” referring to dwarf while scientifically it implies to the unit of length that equates to 1 billionth of a meter or 1 × 10−9 m and represented as nm in SI units (De Jong and Borm, 2008). The concept of particle existence at nano scale level has long existed in nature. To get a better perception to this unit of length, the biological moieties such as nucleic acid, proteins, cyto-skeletal polysaccharides and cell membrane channels are considered as a scale of reference (Aitken et al., 2004). For example, the blood cells – neutrophils, eosinophil, basophils and lymphocytes are present within a size range of 10–15 nm, while the nucleotides are of 0.33 nm and are aligned to form the helically coiled DNA spanning a width of 2–3 nm. These examples clearly demonstrate that the “nano” ideology has not been created defying the laws of nature.
Optimal design of a two-point variables skip-lot sampling plan with Taguchi capability index
Published in Quality Engineering, 2023
To illustrate the applicability of the approach proposed in this study, we conducted the plan in the concrete case for resistor manufacturing, presented by Pearn and Wu (2006). The two-sided tolerance limit for one type of resistor is (i.e., the target value is 10 mil). Mil is a unit of length and equals one-thousandth of an inch. The protections for producers and consumers against the lot quality () with f = 1/10 are chosen, and the plan parameters obtained from Table 1 are (n, k, i) = (60, 1.1812, 3). The operation for inspection is described as follows: Lot-by-lot inspection should first be executed. A sample of size 60 is taken at random from each lot and the Anderson-Darling (AD) normality test is required to examine whether the data follow a normal distribution or not. Next, the estimators, e.g., and estimator of were calculated based on the recorded measurements. The lot disposition for the current lot can lastly be addressed.
On plane internal waves: their amplification, and potential to break in a rotating stratified quiescent fluid
Published in Geophysical & Astrophysical Fluid Dynamics, 2019
Andrei Natarov, Kelvin J. Richards
In this article, we use both dimensional and non-dimensional parameters. The dimensional parameters are denoted by the Latin letters, whereas their non-dimensional counterparts are denotes by the Greek letters. For example f, N, ω are various dimensional frequencies, and and are the non-dimensional frequencies. The only fundamental units we use are metre, as a unit of length, and second, as a unit of time. All dimensional parameters are therefore assumed to have units that are a combination of metres and seconds: for example, f=0.1 should be interpreted as f=0.1 s−1.