Optical fabrication and testing spans an enormous range of manufacturing procedures and optical test configurations.
The manufacture of a conventional spherical lens typically begins with the generation of the optic's rough shape by grinding a glass blank. This can be done, for example, with ring tools. Next, the lens surface is polished to its final form. Typically this is done by lapping—rotating and rubbing the rough lens surface against a tool with the desired surface shape, with a mixture of abrasives and fluid in between.
Typically a carved pitch tool is used to polish the surface of a lens. The mixture of abrasive is called slurry and it is typically made from cerium or zirconium oxide in water with lubricants added to facilitate pitch tool movement without sticking to the lens. The particle size in the slurry is adjusted to get the desired shape and finish.
During polishing, the lens may be tested to confirm that the desired shape is being produced, and to ensure that the final shape has the correct form to within the allowed precision. The deviation of an optical surface from the correct shape is typically expressed in fractions of a wavelength, for some convenient wavelength of light (perhaps the wavelength at which the lens is to be used, or a visible wavelength for which a source is available). Inexpensive lenses may have deviations of form as large as several wavelengths (λ, 2λ, etc.). More typical industrial lenses would have deviations no larger than a quarter wavelength (λ/4). Precision lenses for use in applications such as lasers, interferometers, and holography have surfaces with a tenth of a wavelength (λ/10) tolerance or better. In addition to surface profile, a lens must meet requirements for surface quality (scratches, pits, specks, etc.) and accuracy of dimensions.
In scientific inquiry and academic research, fabrication is the intentional misrepresentation of research results by making up data, such as that reported in a journal article. As with other forms of scientific misconduct, it is the intent to deceive that marks fabrication as highly unethical and different from scientists deceiving themselves. In some jurisdictions, fabrication may be illegal.
Examples of activities that constitute fabrication include:
Outright synthesis of experimental data; reporting experiments that were never conducted. Sometimes referred to as "drylabbing".
"Fudging", "massaging", or outright manufacture of experimental data.
Some forms of unintentional academic incompetence or malpractice can be difficult to distinguish from intentional fabrication. Examples of this include the failure to account for measurement error, or the failure to adequately control experiments for any parameters being measured.
Fabrication can also occur in the context of undergraduate or graduate studies wherein a student fabricates a laboratory or homework assignment. Such cheating, when discovered, is usually handled within the institution, and does not become a scandal within the larger academic community (as cheating by students seldom has any academic significance).
Precision is the authorized march of Royal Military College of Canada. The RMC band performs Precision on parades for march pasts, on Ex Cadet Weekends for the parade to the Memorial Arch, and on the return, the Cadet Wing sings Tom Gelley’s words to welcome the Ex Cadets to the Parade Square.
Precision was composed in 1932 by Denise Chabot, wife of Major C. A. Chabot, a Royal Canadian Artillery officer on staff as professor of French at the College at the time. She earned the degree of Associate of the Royal Conservatory of Music and was the president of the Kingston Music Club.
Precision was inspired by "Madelon", one of the popular marching songs sung and whistled by the cadets marching on their way to the Riding School, and the favourite song of the Class of 1932. Mme Chabot improvised a variation on the song, to represent the cadence of the cadets on the march. The composition starts, “We are the gentlemen cadets of RMC We have sworn to love and serve Her Majesty…”
In statistics, the dual term variability is preferred to the use of precision. Variability is the amount of imprecision.
There can be differences in usage of the term for particular statistical models but, in common statistical usage, the precision is defined to be the reciprocal of the variance, while the precision matrix is the matrix inverse of the covariance matrix.
One particular use of the precision matrix is in the context of Bayesian analysis of the multivariate normal distribution: for example, Bernardo & Smith prefer to parameterise the multivariate normal distribution in terms of the precision matrix rather than the covariance matrix because of certain simplifications that then arise.
The term precision in this sense (“mensura praecisionis observationum”) first appeared in the works of Gauss (1809) “Theoria motus corporum coelestium in sectionibus conicis solem ambientium” (page 212). Gauss’s definition differs from the modern one by a factor of . He writes, for the density function of a normal random variable with precision h,
Five additional Central Solenoid modules, plus one spare, are at various stages of fabrication ... Each 4.25-meter (14-foot)-diameter, 110-ton (250,000-pound) module requires more than two years of precision fabrication from more than 5 kilometers (3 miles) of steel-jacketed niobium-tin superconducting cable.
Over the years, he has established a reputation for delivering with quality and precision — repeat customers validate this ... He fabricated The Joshua Tree Boutique and Gather on Main iron signs. In Gather on Main, Young repaired and fabricated the corbels. He also fabricated the butterflies for the MigratePrinceton art installation ... .
The global Aerospace Fabrics market forecast for 2020-2027 tracks the latest market dynamics, such as concluding factors, restrictive factors, and industry updates such as product innovation, mergers, acquisitions, and investments ... https.//www.marketresearchoutlet.com/report/aerospace-fabrics-market-report-2021/request-sample ... Upholstery Fabrics.
Resgreen GroupInternational has moved to a larger facility to meet the increasing needs and demands of rapid development and fabrication of current and future products. Working in close proximity with a vital supplier, AtlanticPrecision Products, RGGI is able to add a new level ...
A Monday night fire caused severe damage to the PrecisionMachineInc ... Precision Machine specializes in the design, engineering, metallurgical expertise, heat treatment, fabrication and repair of custom mechanical components in heavy industry, including computer numerical controls.
It feels gratifying to close the rips in the fabric of your environment, sealing up torn materials with a fresh patch of thread ... But other aspects of the game fall short of being satisfying, and I think it comes down to a lack of precision.
“It’s amazing to take fabric and designs and create.” ... Louis... Applique is essentially the process of sewing cut fabric of any shape onto the base material. Needle turn involves what are called seam allowances, a precise amount of fabric beyond what will show on the finished quilt ... There are new tools, fabrics and finer needle options ... to 5 p.m ... .
Dir. Craig Gillespie. Starring ... 12A, 134 mins ... She’s a perfect centrepiece for a film like Cruella ... Cruella sees a war waged in silk, leather, and lace, with Estella’s DIY aesthetics - her outfits seemingly cobbled together from fabric scraps - pitted against the precise silhouettes of the Baroness’s traditional, Dior-esque fashion house ... .
IRR is an industrial construction company that specializes in welding, millwright services, pipefitting, and fabrication ... They do precision maintenance, welding, fabricate pressure vessels, create mobile restaurant space from shipping containers, repair turbines and drive trains, turn-key project installations and also offer engineering services.
This machine lets you create with more than 300 materials, from the most delicate paper and fabric to tougher materials like leather and balsa wood, all with incredible precision ... and adding decorative effect, allowing impressive precision when making a variety of projects.