Xiaolan Yao, Xiangtao Yu, Qinghe Wu and Qihong Liang
The purpose of this paper is to solve the problem of a pure time delay in the hydraulic automatic gauge control (HAGC) system.
Abstract
Purpose
The purpose of this paper is to solve the problem of a pure time delay in the hydraulic automatic gauge control (HAGC) system.
Design/methodology/approach
Smith predictor is selected to solve pure time delay of the HAGC system. The model of thickness predictor is identified by the extended recursive least square algorithm. The parameters of controller are adjusted by particle swarm optimization algorithm (PSO). The simulation result shows that the Smith predictor has good response performance and anti‐disturbances ability.
Findings
The control precision of the HAGC system in the finished mill can be obviously improved by Smith predictor with PSO arithmetic. The Smith predictor with PSO arithmetic is suitable to solve the pure time delay in the HAGC system.
Research limitations/implications
Randomicity in rolling process and the effect of other mill stands are the main limitations based on which the model will be applied.
Practical implications
A very useful method to improve the precision of the strip.
Originality/value
This paper presents a new method of Smith predictor with PSO arithmetic is designed for a HAGC system in the finished mill to solve a pure time delay problem. The object model is acquired by system identification method.
Details
Keywords
Xiao‐lan Yao, Xiang‐tao Yu, Qing‐he Wu and Qi‐hong Liang
The purpose of this paper is to reduce the crop losses at two ends and both sides of a plate in the rolling process, to produce a rectangular plan view pattern plate and to…
Abstract
Purpose
The purpose of this paper is to reduce the crop losses at two ends and both sides of a plate in the rolling process, to produce a rectangular plan view pattern plate and to enhance the total product yield of the plates.
Design/methodology/approach
Based on sample data and the unchangeable principle of the slab volume in the rolling process, the predictive MAS control models were set‐up. They are width broad MAS predictive model, width broad MAS control model, gaugemeter automatic gauge control (GM‐AGC) model, and plates tracking model. After the models were tuned, the rolling test was implemented at LinFen Iron & Steel Co., Ltd.
Findings
It is found that by accurately predictive online modeling of MAS methods, the plan view pattern control can be applied in plate mills.
Research limitations/implications
As the rolling process is in high temperature, the plan view pattern is difficult to be detected. Normally, the real‐time abnormity distortion cannot be obtained.
Practical implications
The test results showed that the crop losses are reduced and the product yield is greatly increased.
Originality/value
This paper presents an accurately predictive online modeling of MAS method.
Details
Keywords
The purpose of this study is to determine the effect of laser treatment on disperse dye-uptake and fastness values of polyester fabrics. Furthermore, it was aimed to evaluate…
Abstract
Purpose
The purpose of this study is to determine the effect of laser treatment on disperse dye-uptake and fastness values of polyester fabrics. Furthermore, it was aimed to evaluate colors directly over the photos of fabric samples instead of color measuring with spectrophotometer which is thought to be useful in terms of online digital color assessment.
Design/methodology/approach
In this study, 100% polyester (150 denier) single jersey knitted fabrics (weight: 145 g/m2, course density: 15 loops/cm, wale density: 24 loops/cm) were used in the trials. The effect of laser treatments before and after dyeing on color was investigated. Laser treatments were applied to fabrics at different resolutions (20, 25 and 30 dpi) and pixel times (60, 80 and 100 µs) before dyeing. The power of the laser beam was 210 W and the wavelength was 10.6 µm. In order to determine the effect of laser treatment on polyester; FTIR analysis, SEM-EDX analysis and bursting strength tests were applied to untreated and treated fabric samples.
Findings
It was found that treatments with laser have a significant effect on disperse dye-uptake of polyester fibers, and for this reason laser-treated fabrics were dyed in darker shade. Furthermore, it was determined that the samples treated at 30 dpi started to melt and the fabric was damaged considerably, but the fabrics treated at 20 and 25 dpi were not affected at all. Another result obtained regarding the use of laser technology in polyester fabrics is that if some areas of fabrics are not treated with laser and some other areas are treated with laser at 20 dpi 60 µs and 25 dpi 60 µs, it will be possible to obtain patterns containing three different shades of the same color on the fabric.
Originality/value
When the literature is examined, it is seen that there are various studies on the dyeability and patterning of polyester fabrics with disperse dyes by laser technology. As it is known, today color measurement is done digitally using a spectrophotometer. However, when we look at a photograph on computer screens, the colors we see are defined by RGB (red-green-blue) values, while in the spectrophotometer they are defined by L*a*b* (L*: lightness-darkness, a*: redness-greenness, b*: yellowness-blueness) values. Especially when it is desired to produce various design products by creating patterns with laser technology, it would be more useful to show the color directly to the customer on the computer screen and to be able to speak over the same values on the color. For this reason, in this study, the color measurement of the fabric samples was not made with a spectrophotometer, instead, the RGB values obtained from the photographs of the samples were converted into L*a*b* values with MATLAB and interpreted, that is, a digital color evaluation was made on the photographs. Therefore, it is believed that this study will contribute to the literature.