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Volume 7, No.1/2007
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DETECTING THE FAULT
FROM SPECTROGRAMS BY USING GENETIC ALGORITHM TECHNIQUES
Amin A. E.1, El-Geheni A. S.2,
and El-Hawary I. A**. El-Beali R. A.3
1Mansoura University, Textile Department
2Prof. Dr. Alexandria University, Textile Department
3Prof. Dr. Mansoura University, Textile Department
During the last thirty years there has been a rapidly
growing interest in the field of genetic algorithms (GAs). The
field is at a stage of tremendous growth, as evidenced by the
increasing number of conferences, workshops, and papers concerning
it, as well as the emergence of a central journal for the field.
With their great robustness, genetic algorithms have proven to be
a promising technique for many optimisation, design, control, and
machine learning applications. This paper presents a new technique
for detecting the source of fault in spinning mills from
spectrograms by using genetic algorithm.
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INVESTIGATION INTO THE
PERIODICITY OF MASS VARIATION OF YARN AND ITS EFFECT ON FABRIC
APPEARANCE
Ferede Addisu and Peer
Mohamed Abdul Hameed
Department of Textile
Technology
A. C. College of Technology
Anna University
The appearance of a fabric can
be greatly affected if the yarn has a sufficiently pronounced
periodic component. The severity of the periodic fault can only be
estimated if its intensity is quantified. Even though a
spectrogram is more reliable than other tools at determining
periodicity, it gives only the resolved mass variation, which may
not be present in the final yarn when different faults are
superimposed. The relative index of irregularity of yarn is
considered as a measure of the intensity of a periodic fault of a
spun yarn. By correlating the above index with the relative
unlevelness indices of finished fabrics knitted from yarn samples
produced at different levels of roller eccentricity, we have
established the threshold value of the relative index of
irregularity of yarn which produces worse appearance values in the
fabric.
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NEW APPROACH TO A THEORETICAL STUDY OF SOME OF THE PARAMETERS IN
THE KNITTING PROCESS, AND THEIR INFLUENCE ON KNIT-FABRIC STITCH
DENSITY
A. Charalambus
Technical University Sofia, Bulgaria
This paper proves relations,
which concern the structure of knitted fabric by using a simple
geometrical model. In addition, a series of graphics are made
which allow fast, simple and effective analysis of the relations
between some of the parameters of the knitting process and these
of the ready-knit fabric. The quantity ‘relative geometrical
prolongation of the thread length in the stitch’, introduced by me
plays a significant role in this study. The relations given below
allow the machine gauge to be defined; this helps to produce knit
fabric with precisely calculated density by choosing appropriate
values for the thread’s sinking depth and acceptable average
geometrical prolongation.
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MOISTURE TRANSMISSION THROUGH TEXTILES
Part I: Processes involved in moisture transmission
and the factors at play
Brojeswari Das1,
A. Das1, V.K. Kothari1, R. Fanguiero2
and M. de Araújo2
1Department of Textile Technology, Indian Institute
of Technology, Delhi, India, 2Department of Textile
Engineering, University of Minho, Guimarães, Portugal
Moisture
transmission through textiles has a great influence on the
thermo-physiological comfort of the human body which is maintained
by perspiring both in vapour and liquid form. The clothing to be
worn should allow this perspiration to be transferred to the
atmosphere in order to maintaining the thermal balance of the
body. Diffusion, absorption-desorption and convection of vapour
perspiration along with wetting and wicking of liquid perspiration
play a significant role in maintaining thermo-physiological
comfort. The scientific understanding of the processes involved in
moisture transmission through textiles and the factors affecting
these processes are important to designing fabrics and clothing
assemblies with efficient moisture transfer in different
environment and workload conditions.
This paper is in two parts.
Part I focuses on the moisture transmission through textile
materials and it discusses the processes involved in moisture
transmission and the key influencing factors at play to
maintaining comfort. It is underlined that the processes which
play the major role in moisture transmission in a particular
situation are dependant on the moisture content of the fabric, the
type of material used, the perspiration rate and the atmospheric
conditions, such as humidity, temperature and wind speed.
Part II is concerned with the selection of the measurement
techniques which are of great importance in determining fabric
factors that influence comfort. The instruments and methods used
for testing purposes should adequately simulate the exact
conditions for which the fabric will be used, in order to
determine the effectiveness of that fabric for a particular
wearing situation and environmental condition. The testing methods
used and the apparatus developed by different researchers for
determining moisture transmission through textiles by different
mechanisms are discussed in this paper. Moreover, this part of the
paper deals with the mathematical models of liquid and vapour
transport through textile materials developed by several
scientists in order to understand the exact phenomena involved and
to predict the factors affecting the transmission under a
particular condition.
When designing the comfort of a clothing product for a particular
application, the requirements may result from needs concerning the
application, the individual wearer and the environmental
conditions.
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MOISTURE/SORPTION CHARACTERISTICS OF STARCH-FILLED POLY
(STYRENE-CO-BUTYL ACRYLATE) LATEX BASED COMPOSITES REINFORCED WITH
POLYESTER
NONWOVEN FABRIC
M.N. Satheesh Kumar1
and Siddaramaiah2
1Research and Innovation Centre, Raman Boards
Limited, Mysore, India.
2Department of Polymer Science
and Technology, Sri Jayachamarajendra College of Engineering,
Mysore, India
Poly (styrene-co-butyl acrylate)
latex was prepared with a 70:30 weight ratio of styrene to butyl
acrylate. The prepared latex was incorporated with various weight
percentages of cornstarch. The cornstarch-filled copolymer latex
was used as a matrix to fabricate the polyester nonwoven fabric
reinforced composites. The pickup ratio of latex to fabric was
maintained at 3.2:1. The moisture sorption characteristics of
composites were examined at 270C for water activity (aw) from 0.1
to 0.9. The sorption data was used to fit six different sorption
isotherm models proposed in the literature. The model constants
were determined by linear fitting of the sorption equations. The
ranges of applicability of water activity for the isotherm models
reported in the article lies between 0.1 and 0.4 (monomolecular
layer) for the Braunauer-Emmet-Teller (BET) model, and between 0.3
and 0.9 (multimolecular and capillary condensation layers) for
other models. The value of the coefficient of determination (R2 =
0.97±0.02) confirms the linear fitting of the equations studied.
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GRAFTING MMA ONTO FLAX UNDER THE INFLUENCE OF MICROWAVE RADIATION
AND THE USE OF FLAX-g-POLY(MMA) IN PREPARING PF COMPOSITES
Balbir Singh Kaith1,
Amar Singh Singha1 and Susheel Kalia2
1Department of
Applied Sciences, National Institute of Technology, Hamirpur
, India
2Department of Chemistry, Singhania Institute of Law, Management,
Science and Technology, Pacheri Bari, Jhunjhunu,
India
This paper deals with the graft
co-polymerisation of methylmethacrylate (MMA) onto flax fibre
under the influence of microwave radiation (MWR). The graft
co-polymers are characterised by FTIR spectroscopy, scanning
electron microscopy (SEM), thermal analysis (TGA/DTA) and X-ray
diffraction (XRD). Graft co-polymers are subjected to the
evaluation of some physical, chemical and mechanical properties.
Graft co-polymers thus prepared are used in the preparation of
phenol-formaldehyde composites. Wear resistance, tensile strength
and compressive strength of composites are measured, and it is
found that composites reinforced with flax-g-poly(MMA) showed
better mechanical properties in comparison to composites
reinforced with raw flax.
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TEXTILE PREFORMS FOR DENTAL APPLICATIONS
Arumugam Poornima,
V.R.Girideva and V.R.Balajib
a Department of Textile Technology, A.C.College of Technology,
Anna University, Chennai, India
b Department of Periodontics,
Meenakshi Dental College, Chennai, India
Dentistry has advanced to the
use of FRCs, which helps patients to live their lifetime with
their dentition intact. A large number of developments in the
field of fibrous composite implants and devices for orthopaedic
and dental applications have taken place. The present paper
discusses the applications of fibre- and textile-reinforced
composites in dental practices, mainly focussing on periodontal
splinting. The conventional methods of splinting and the design &
use of fibre-reinforced composites as restoratives to stabilise
and splint teeth have been discussed in detail. The current
controversy of incorporating implants in patients requiring
splinting is discussed in relation to the various fibres applied
as reinforcement for the splinting material.
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