Search results for "Lock in"
showing 3 items of 3 documents
Does brick size matter? Albert G. Keller on another QWERTY story
2023
In his seminal ‘‘Clio and the Economics of Qwerty’’, Paul David indicates Thorstein Veblen’s famous discussion of the British system of coal rail haulage as an intellectual antecedent to the idea of lock in. This note documents how Albert G. Keller, a Yale sociologist contemporary of Veblen, had presented a similar argument in connection to the establishment of a brick tax in England and its effects on the size of bricks. Like Veblen, Keller used this illustration to emphasize the inertia exercised by certain institutional conditions.
Implementation of a fast and low cost IR-NDT technique by means of a Square Pulse modulated Lock-In Thermography
2012
This work describes the development of an IR-NDT procedure based on a lock-in signal treatment in the frequency domain to obtain phase-contrast defect signatures. Heat stimulation is obtained by periodically shattering a common low-power halogen lamp. The delivered heat is then modulated as a train of square waves with multi-frequency harmonic content. The proposed lock-in algorithm is able to selectively retrieve phase and amplitude information at various frequencies of the acquired temperature, acting also as a narrow band filter to improve defect-signature to noise ratio. The procedure is implemented and evaluated by means of low cost IR equipment to investigate artificially defected thi…
A comparison of injection pain with articaine with adrenaline, prilocaine with phenylpressin and lidocaine with adrenaline
2008
Kutuk, Nukhet/0000-0001-6563-1899 WOS: 000259667200006 PubMed: 18587306 Objective: The objective of the present study was to investigate the pain on injection of articaine with adrenaline, prilocaine with phenylpressin, and lidocaine with adrenaline. Study Design: The study sample was comprised of 497 consecutively seen patients received 497 maxillary buccal infiltration injections or inferior alveolar block injections of 4% articaine with 1: 200.000 adrenaline, 3% prilocaine with 1.08mcg phenylpressin, or 2% lidocaine with 1: 100.000 adrenaline. Immediately after the injection, patients were asked to rate their injection pain on a six-point scale. Results: There were no significant differe…