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21.
THE DEVELOPMENT of testing techniques and procedures required to understand the performance of devices used to measure water currents has proven to be one of the most difficult and challenging tasks that the oceanographic community faces. It has long been recognized that some type of controllable relative water motion was a necessary element in the process of determining the accuracy of a current meter. A widely accepted solution is the towing tank where a current meter fastened to a moving carriage is moved through "still" water. A simple measurement of carriage speed over the ground compared to the current meter's flow measurement gives an indication of the accuracy of the device. Although this approach satisfied many, a sense that this technique was not sufficient spawned a few short-lived attempts at simulating time-varying flow conditions and developing deterministic models (transfer functions) for the response of inertial transducers. In addition, mathematical modeling of the motion of buoy moorings was attempted by a variety of investigators. In the late 1960's and early 1970's, the response of a current meter to the complex time-varying ocean environment became a major issue within the oceanographic community. It was clear that this information could not be obtained by simple steady-flow tow tank testing and that either dynamic controllable techniques must be developed or our ability to characterize the measurement environment must be improved. 相似文献
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CO Lacertae is one of the very few known binaries with both a short period of apsidal motion and good M, L, R data. Our newU, B, V light curves provide two times of minima and a check on Semeniuk's value forP aps. This is the first published example of an eclipsing binary analysed in terms of a physical model (as opposed to a model based on spherical or ellipsoidal star figures) which allows for eccentric orbit effects. The light curves show some peculiarities — particularly a large, probably intrinsic, scatter. 相似文献
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Omissions in the subject paper, especially lack of reference to one 1968 paper by the author of this letter, may tend to mislead the reader. The subject paper was perhaps too brief to clear the record. 相似文献
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