17—TRANSDUCERS FOR THE PRECISION MEASUREMENT OF WEFT-KNITTING FORCES. PART III: THE EXPERIMENTAL MEASUREMENT OF CAM AND YARN FORCES

Selected experimental results of dynamic forces recorded during knitting are reported. These were obtained by using a cam-force transducer designed to measure the dynamic forces between a latch-needle and the stitch and guard cams (see Part I) and a yarn-force transducer designed to measure the forces exerted upon the sinker and needle by the yarn during the formation of the knitted loop (see Part II).     

30—CAM-TO-NEEDLE IMPACT FORCES IN WEFT-KNITTING PART VII: THE INFLUENCE OF YARN TENSION AND MACHINE SPEED ON GUARD-CAM IMPACT

The results of experiments designed to investigate the effects of yarn-loop-drawing tension and machine speed upon the impact force between the needle and the guard cam are compared with theoretical values obtained by analytical procedures detailed in Part V, and the agreement is shown to be reasonably good. The impact force increases in direct proportion to the machine speed; increasing the yarn-loop-drawing tension delays the onset of the impact and reduces the magnitude of the impact force.     

Rethinking the size of scientific specialties: correcting Price’s estimate

I aim to advance our understanding of the size of scientific specialties. Derek Price’s groundbreaking work has provided us with valuable conceptual tools and data for making progress on this issue. But, I argue that his estimate of 100 scientists per specialty is flawed. He fails to take into account the fact that the average publishing scientist publishes only 3.5 articles throughout her career. Hence, rather than consisting of 100 scientists, I have suggested that specialties are probably somewhat larger, perhaps somewhere between 250 and 600 scientists.     

COMPARATIVE TESTS OF CHINAWARE USING TWO FORMS OF TESTING MACHINES1

Two forms of impact testing machines, designed to determine the resistance of chinaware to chipping and impact, and their use in testing chinaware are described. The results of testing 33 brands of domestic and foreign-made ware with these machines are given. In addition, the weight, dimensions, and percentage of water absorption of the ware are given.     

Vectored injection into compressible laminar and turbulent boundary layers

A fundamental analysis of two-dimensional supersonic boundary layer flow, both laminar and turbulent, is presented for a wide range of normal and nonnormal mass-transfer velocities. The analysis is based on the numerical solution of the Navier-Stokes equations, and results are compared with available theoretical and experimental data. Certain cases of practical importance, for which results are not presently available, are referred to.     

Sensitivity of direct gain space heating performance to fundamental parameter variations

A computer program has been developed for analyzing the performance of direct gain passive solar heated enclosures. The computer program is validated by comparison with data from passive solar test cells at LASL. The results of a sensitivity study involving variation of fundamental design parameters is presented.     

Plastic deformation of austenitic iron at intermediate strain rates

The plastic deformation of austenitic iron, represented by a zone-refined iron, an electrolytic iron, an Fe-0.05C alloy, and an Fe-5.2 Mn alloy, has been documented for the temperature range 950 to 1350°C (1740 to 2460°F) and the strain-rate range 2.8 x 10^-5 to 2.3 x 10^-2 s^-1. The intrusion of recrystallization during deformation restricts the documentation to initial periods of strain usually less than 0.10. The general problem of retaining grain structures representative of polycrystals in specimens annealed at temperatures above 0.95T _mis recognized, and a basis for its solution is presented. Chemical composion appears to influence the plastic-flow behavior of austenitic iron primarily through its effect on the grain structure. Thus, the large-grained zone-refined iron is relatively weak, and the difference in behavior between the Fe-0.05 C alloy and the Fe-5.2 Mn alloy is small. M. F. HOLMES, formerly Associate Scientist, U.S. Steel Corporation.