Part 1 described, with the aid of van Wyk's theory and Dr . Wakayama's Works, a new formula on the compression of fiber assemblies.
This instalment presents two formulas on the relation between aparent density γ (gcm^-3) and height h (cm) of fiber assemblies in a brass reserve box.
One is a practical formula induced by the compressive properties of fiber assemblies and the results,
γ=0.002/μ(1-e^-0.11μh)
μ=0.103(2.86×10^-8 h³-1.63×10^-5 h²+3.78×10^-3 h- 5.72×10^-2)^-0.443
where μ is aparent coefficient of friction between fiber assemblies and the wall of the brass reserve box.
The other is an experimental formula with the following result:
γ≈ 2×10^-2(2.86×10^-3h³-1.63×10^-5h²+3.78×10^-3h-5.72×10^-2)^1/2

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Although the reflective property of fabrics is important to the assessment of gloss, it is complicated because it is affected by fabric geometry and optical condition. Much research work has been done in this field, but only meager data have been obtainable on the relation between reflective property and fabric geometry. This article seeks to clarify the effect of fabric geometry on the reflective property by examining the effects of dyeing and tension treating, and to establish a suitable expression for gloss index.
Our experiments have shown that reflective property is varied considerably by dyeing and in correspondence to fabric geometry by tension treating. On many undyed fabrics, the maximum reflex intensity is nearly at an angle of 0° of view at a rather small incidence angle. The maximum reflex intensity is brought close to a specular angle by dyeing.
It is reasonable to express gloss index G_c=ρ_max/ρ₀, where ρ_max is the maximum reflex intensity and ρ₀ is intensity at an angle of 0° of view.

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We have measured the dynamic property of the drafting process by the frequency response method, with the following results:
(1) The transfer function G_p(s) of the control system, in less than 20 rad/sec, is
G_p(s)=k_p ω²_np(1+T_ps)/s²+2ξ_p ω_nps+ω²_np
where ω_np, ξ_p and T_p are constants determined by drafting conditions.
(2) The transfer function G_pn (s) of drafting process is
G_pn(s) =1/D ω_np(1- T_n S)/s²+2ξ_pω_nps+ω²_np
where D is draft ratio (V_f/V_b) and T_n is time constant of back roller (C₂/V_b).

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The speed-up of card and drawing machines requires a high-speed controller. The conventional control apparatus limits the speed of sliver supply to 20 m/min. This article shows that it is possible to control the unevenness of slivers at 35m/min. Unevenness control by high-speed sliverfeeding is closely related to the control apparatus and its characteristics.
1. The overall time lag, including dead time, which is determined by frequency response, the roller gage and the speed of sliver supply are closely related to one another. We must select an overall time lag which keeps unevenness from increasing. In other words, the roller gage must be not too large.
2. The frictor must be related to the proportional gain, and unevenness must not increase because of the passage of slivers through the frictor. The proportional gain had better be near 1.
3. The roller weight must be proper.
4. The sliver used in our experiment was 280 grain/6 yards, a doubling of 2 slivers. The dead time was 0.015 sec. Time constant was 0, 120 sec. The proportional gain was 1.14. U% is decreased from 3.2 to 2.6.

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