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A novel "Shoelace" antenna has been used to inductively excite a short-wavelength edge fluctuation in a tokamak boundary layer for the first time. The principal design parameters, k˔ = 1.5±0:1 cm-1 and 45 < f < 300 kHz, match the Quasi-Coherent Mode (QCM, k˔ ~ 1.5 cm-1; f ~ 50 - 150 kHz) in Alcator C-Mod, responsible for exhausting impurities in the steady-state, ELM-free Enhanced Dα H-mode. In H-mode, whether or not there is a QCM, the antenna drives coherent, field-aligned perturbations in density, ñe, and field, B~θ, which are guided by field lines, propagate in the electron diamagnetic drift direction, and exhibit a weakly damped (γ/ω0 ~ 5% - 10%) resonance near the natural QCM frequency. This result is significant, offering the possibility that externally driven modes may be used to enhance particle transport. In L-mode, the antenna drives only a non-resonant B~θ response. The facts that the driven mode has the same wave number and propagation direction as the QCM, and is resonant at the QCM frequency, suggest the antenna may couple to this mode, which we have shown elsewhere to be predominantly drift-mode-like [B. LaBombard et al., Phys. Plasmas 21, 056108 (2014)]. [ABSTRACT FROM AUTHOR]

A name index for the March 1, 1974 issue of "A Critical Appreciation of Recent Developments," is presented.

References for the March 1, 1974 issue, "A Critical Appreciation of Recent Developments," are presented.

A subject index for the March 1, 1974 issue of "A Critical Appreciation of Recent Developments," is presented.

The section of "A Critical Appreciation of Recent Developments" presents information related to tape and fibrillated yarns. It is reported that the production of tape and fibrillated yarns has been one of the remarkable developments in textiles in the last decade. It is further reported that the production has resulted in the dismissal of bast fibres such as jute, sisal, and hemp from end-uses like carpet-backings, cords, and industrial fabrics. It is stated that the techniques of producing tape yarns are explained in a monograph which contains chapters covering the primary stages of production, the production processes, the properties of polyolefin tape yarns, the production of tape fabrics, the application of tape yarns, and future prospects.

The section of "A Critical Appreciation of Recent Developments" focuses on texturing, a branch of textile technology. The three basic processes included in the production of a textured continuous-filament yarn include spinning, drawing, and texturing. It is stated that false-twist texturing is one of the most popular technique for producing textured yarns in fine linear densities. The air-jet texturing, another method of texturing, involves blowing a jet of compressed air into a group of filaments.

The section of "Yarn Production and Properties" focuses on present developments in the field of raw materials which are related to the modification of natural fibres to improve processing potential. It has been stated that one such modification is the artificial crimping of carpet wools by means of a machine developed by the International Wool Secretariat (IWS). It is also reported that the very high cohesiveness of wool and cotton roving immediately after treatment can be used to improve spinning beyond the extent achieved when treatment is followed by delayed processing.

The section of "Yarn Production and Properties" focuses on automation in the field of the textile industry. It has been stated that full or partial automation of yarn manufacture, especially for cotton-spinning, was one of the developing concepts during the 1960s. It has also been reported that automation means the linking together of different processes that have for long been regarded as separate, with a manual transfer of material from the output of one stage to the input of the following stage.

The section of "Yarn Production and Properties" focuses on the combing of fibres. It is stated that combing is one of the last sections of yarn manufacture to come under really detailed scrutiny by textile technologists and scientists. It is also mentioned that wool combing has received greater attention in the published literature than has short-staple combing. After decline in the number of wool-combing machines in use, there is evidence that during 1973 the number rose slightly in Great Britain.

The section of "Yarn Production and Properties" focuses on yarn properties. It is stated that comparisons between the properties of conventional and new-type yarns have been particularly numerous. Continuing work on the yarns' irregularity and slivers has exercised the minds of workers. The range of yarns can be extended by the introduction of heads designed for coarse yarns. It is also mentioned that the necessary degrees of blend uniformity, short- and long-term irregularity and tenacity cannot be decided upon unless the end-user of a yarn is specified.

The section of "Yarn Production and Properties" focuses on the opening, cleaning and blending processes in cotton-spinning. It is stated that fibre-blending practice has been discussed in a paper that considers the reasons for blending, methods of blending, calculation of the average cost of a blend, and problems associated with the blending of man-made fibres. It is also mentioned that the incidence of kemp or heavily medullated fibre is one of the major problems in the processing and use of mohair.

The section of "Yarn Production and Properties" focuses on the systems of yarn manufacture. It is stated that the complete spinning process involves different operations including wetting out the roving, drafting, starch impregnation, consolidation, packaging and gelatinization. Core yarns consisting of a polyester-fibre core and a cotton sheath can be examined with respect to their properties. It is also reported that the core-spun yarn can be constructed from 20-den nylon monofilament surrounded by three types of staple-fibre covering.

The section of "Yarn Production and Properties" focuses on open-end spinning. According to a research related to the economic viability of open-end spinning, it is the appropriate technique for short-staple yarns coarser than 28s-30s cotton counts. This research was conducted by the company Platt International Ltd. It is mentioned that the open-end spinning acceptability to the textile industry has been discussed in several papers by Japanese authors who have had more operating experience than anyone else.

The section of "Yarn Production and Properties" focuses on conventional spinning in the field of the textile industry. It is stated that many papers have been published during the period under review that describe developments in the recent time in the broad field of staple-fibre yarn spinning. It is also reported that the amount of attention that has recently been focused on newer and sometimes novel methods of spinning has raised different questions which related to the future of the ringframe.

The section of "Yarn Production and Properties" focuses on drawing in the field of the textile industry. It is stated that the importance of adequate blending before drawing has led to the introduction of specially designed machines for this purpose. It is also mentioned that vertical drafting is considered more important as speeds increase, when projection of a fibre forwards and parallel to the ground is becoming more difficult unless that fibre has a very high degree of rigidity to maintain it in an extended state against the pressure to which it is being subjected.

The section of "Yarn Production and Properties" focuses on drafting and autolevelling in the field of yarn production. It is mentioned that the introduction of open-end-spinning machines has not detracted from the key part that roller-drafting will continue to play in the attenuation and blending of slivers of all kinds and in spinning by more traditional methods. The elimination of the draft gearing says that each spinning position can include a simple clutch, whose operation is controlled automatically via a yarn-break detector so that the feed is stopped if the end should break down.

The section of "Yarn Production and Properties" focuses on carding. It is stated that arrangements for feeding to a series of carding machines have been enhanced. It is also mentioned that the invention that movable panels employed in the chutes to compact the fibres may have an undesirable effect on the regularity of the carded sliver when the panels in all the chutes are in phase for extended periods has suggested that this synchronization be prevented, so that a more stable air-pressure is maintained in the chutes.

An account is given of the development of a technique for the assessment of the streakiness of fabrics knitted from worsted blended-fibre yams in which the fibres constituting the blend are of different colours. A filter colorimeter was used for the tests, and an account is given of trials made to determine the optimum conditions for it. The results of tests made with the instrument are compared with visual assessments of the streakiness of knitted fabrics, and it is shown that only when the fabrics were of a similar degree of streakiness and the judges were unable to distinguish between them was the correlation between the subjective and objective methods of assessment low. It is concluded that the instrumental technique possesses distinct possibilities for application to the evaluation of the streakiness of colour-mixture yams and of fabrics made of them. [ABSTRACT FROM AUTHOR]

An account is given of the effect on the streakiness of coloured worsted yams of the use of different blending techniques, levelling colours, and different counts. The yarns were knitted into fabrics, and the streakiness of the fabrics was assessed by a panel of judges, whose ranking of the fabrics was analysed statistically. It is shown that the number of doublings employed during drawing has no effect on fabric streakiness. No difference in streakiness was observed between yams spun on a high-draft system and those spun on a conventional system. When pre-mixing was omitted, decreasing the weights of slivers and increasing their number produced only a slight improvement in the degree of mix, and maintaining an orderly arrangement of slivers behind the gill-box by means of special sliver guides led to only a slight improvement. Card-mixing is shown to be a valuable mixing technique that deserves serious consideration. The inclusion in a blend of additional components whose colours are intermediate to the original ones is a valuable means of reducing streakiness, and it is shown that streakiness decreased progressively as the proportion of levelling colour was increased. Increasing the number of levelling colours and their proportion in the blend was found to reduce fabric streakiness. The use of coarser yarns led to a reduction in fabric streakiness. [ABSTRACT FROM AUTHOR]

The section of "A Critical Appreciation of Recent Developments" focuses on the textile industry's actions which are directed towards environmental hazards. It is reported that noise levels depend largely on the design of the spinning room. It is further stated that operatives are not to be consistently exposed, over long periods, to a noise-emission level higher than 90 dBA. It is stated that the dust is common to the manufacturing of fibres. It is further informed that the dust problem in cotton-processing has been linked to the industrial diesease of byssinosis.

The section of "Yarn Production and Properties" focuses on self-twist spinning. It is mentioned that the most comprehensive description of the basic principles of self-twist spinning will be found in a monograph that contains chapters on the basic concepts, the methods of inserting alternating twist, the oscillating-roller twister, twist distribution from the roller twister, self-twist-yarn properties, alternative spinning systems utilizing self-twist, the self-twist spinner, STT (self-twist-twisted) yarn, and prospects for self-twist yarns.