The effect of inlet angles of a tapered channel on viscoelastic flow in Maxwell model was numerically investigated by the perturbation method using oblique coordinates. These results have shown that the characteristic flow pattern of viscoelastic liquids such as a shape of a wine glass is produced by the abrupt contraction into a slit rather than by turning round a corner, and, in addition, that the inlet angle of a tapered channel has little effect on the shape of the main flow.

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The theory of the mechanics of twisted homogeneous filament yarns is extended in terms of fibre angles to the yarn axis. Firstly, an axial strain of an element in a yarn is generally considered in the three dimensional analysis. The axial stress of the element is then examined in terms of each element angle to the axis. From these analyses on, the yarn stress can be discussed as a function of the filament angles to the yarn axis as well as the distribution function for the angles and the filament stress according to the strain. Secondly, in order to confirm the possibility that a yarn stress-strain curve can be computed by knowing the distribution for the angles, some simple mathematical models are applied as general distribution functions for the filament angles in a yarn.
Practical yarns are then discussed. As a case study, the prediction of the stress-strain curve of a randomly interlaced yarn, with a filament angle served by the Normal Distribution, is carried out. The theory and computer programs developed here can be used not only to compute but also to predict the stress-strain curves of each particular structure of homogeneous filament yarn such as the single, the ply, even or the cabled yarn. Numerical and graphical outputs of estimated yarn stresses will be obtained by the input of experimental data and assumed values.

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To achieve a technological progress in a pattern designing and production field of weft knitting, computerized weft knitting machinehas been developed. The main features of the electronic weft knitting machine are :
(1) A pattern control part and mechanicalcontrol part of conventional jacquard weft knit-ting machine are computerized, then weft knitting machine can be operated by the aid ofpattern information tape, knitting stitch information tape and machine control tape.
(2) A pulse-motor type actuater, mountedon the carriage of the electronic weft knitting machine, selects the each knitting needle offront or back needle bed, and then produces aknitting pattern.
(3) Since a conventional jacquard weft knit-ting machine is easy to modify, this electronicweft knitting technique is highly processablefor a variety of weft knitting machine types.
(4) Specification : Gauge=8/inch, feed = upto 6 colours, cam=single 2-step RAHBEN cam, width =100 cm/needle bed, speed=approx. 24courses/min.
(5) Using the electronic weft knitting machine and pattern analyser, only one operatorcan quickly (within 1 hour) operate from patternanalysing to electronic weft knitting of large pattern, then making possible time-and laboursaving, worthy weft knit production and quickdelivery to meet market needs.

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