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Dissertations / Theses on the topic 'Yarn'
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Goksoy, M. "A study of yarn-on-yarn abrasion." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382649.
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Chang, Lingli, and mikewood@deakin edu au. "An investigation of yarn hairiness." Deakin University. School of Engineering and Technology, 2002. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20060823.141926.
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Yarn hairiness affects not only the quality of products, but also the productivity in spinning and weaving. Too much yarn hairiness is undesirable for many end uses as well as the spinning and post spinning processes. The main aims of this project are to examine the hairiness features of various yarns and to reduce yarn hairiness. The thesis covers five related areas hairiness assessment, factors affecting yarn hairiness, the hairiness of newly developed yarns, yarn hairiness reduction, and effect of yarn hairiness on the energy consumption in ring spinning.
The worsted cashmere, pure wool and wool/cashmere blend yarns were employed to investigate the effect of some fibre parameters on the yarn hairiness. A single exponential distribution of the hair-length was confirmed first, using the data from the Zweigle G565 Hairiness Meter. A linear relationship was observed between the blend ratio and the hairiness indexes. In particular, the effect of fibre crimp or curvature on yarn hairiness is examined. The theory of yarn hairiness composition was also developed further.
The effect of draft ratio and spindle speed on the hairiness of worsted wool yarn was examined next with a factorial experiment design. Several new hairiness indexes, namely the relative hairiness indexes, have been used to explain the results obtained.
In the investigation of the hairiness of newly developed yarns, the hairiness of the Compact Spun and Roller-Jet-Spun yarns was examined first. The composition of the yarn hairiness, the hair-length distribution, and the effect of test speed on yarn hairiness were then studied. An important finding is that for both yarns, the predominant hairiness feature is the looped hairs.
A comparison of the hairiness of Solospun yarns and the equivalent ring spun wool yarns was undertaken. The hair-length distribution of the Solospun yarn was examined first. The Solospun yarns used had fewer hairs in most hair-length groups and lower variations in hairiness. In addition, the effect of twist level and spindle speed on the hairiness of Solospun and conventional ring spun yarns has also been discussed.
A novel approach of reducing yarn hairiness spinning with a Diagonal yarn path was examined next. Both Left Diagonal and Right Diagonal yarn arrangements were studied. A new finding is that the Right Diagonal yarn path leads to reduced hairiness for the Z-twist yarn, while yarn evenness and tenacity are not as sensitive to the modified yarn path. The mechanism of hairiness reduction with the Diagonal yarn path has been discussed. The spinning performance of Right Diagonal yarn arrangement has also been evaluated.
Finally, the effect of yarn hairiness on the energy consumption in ring spinning has been investigated theoretically and experimentally. A theoretical model has been developed, which represents the first attempt at theoretically investigating the influence of yarn hairiness on energy consumption during the winding stage of ring spinning. The experimental results have generally confirmed predictions of this model. Recommendations for further research in this area have also been made in the concluding chapter of this thesis.
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He, Peng. "Process-structure-property relationships of yarns produced on the card-spinning system." Thesis, Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131148/unrestricted/he%5Fpeng%5F200405%5Fms.pdf.
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Daniel, Latson Trudie I. "A GRIOT’S YARN." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1310406150.
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Giannokostas, Vasileios. "Policy-Driven YARN Launcher." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204461.
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In recent years, there has been a rising demand for IT solutions that are capable to handle vast amount of data. Hadoop became the de facto software framework for distributed storage and distributed processing of huge datasets with a high pace. YARN is the resource management layer for Hadoop ecosystem which decouples the programming model from the resource management mechanism. Although Hadoop and YARN create a powerful ecosystem which provides scalability and flexibility, launching applications with YARN currently requires intimate knowledge of YARN’s inner workings. This thesis focuses on designing and developing support for a human-friendly YARN application launching environmen twhere the system takes responsibility for allocating resources to applications. This novel idea will simplify the launching process of an application and it will give the opportunity to inexperienced users to run applications over Hadoop.De senaste åren har haft en ökad efterfrågan på IT-lösningar som är kapabla att hantera stora mängd data. Hadoop är ett av de mest använda ramverken för att lagra och behandla stora datamängder distribuerat och i ett högt tempo. YARN är ett resurshanteringslager för Hadoop som skiljer programmeringsmodellen från resurshanteringsmekanismen. Även fast Hadoop och YARN skapar ett kraftfullt system som ger flexibilitet och skalbarhet så krävs det avancerade kunskaper om YARN för att göra detta. Detta examensarbete fokuserar på design och utveckling av en människovänlig YARN applikationsstartsmiljö där systemet tar ansvar för tilldelning av resurser till program. Denna nya idé förenklar starten av program och ger oerfarna användare möjligheten att köra program över Hadoop.
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Mirfakhrai, Tissaphern. "Carbon nanotube yarn actuators." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/17441.
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The first demonstration of electromechanical actuation in carbon nanotubes (CNTs), aligned in the form of a twisted yarn, is presented in this thesis. Sheets of CNTs have been known to actuate when charged electrochemically. When an electric potential is applied between a sheet of CNTs and another electrode, both submersed in an electrolyte, the sheet expands. Actuation loads and stresses are low (< 33 MPa); this is partly due to the random orientation of CNTs in those sheets. When actuated under similar conditions, the yarns show significantly higher stress (2.0±0.4 x 10⁸ Pa) with similar strain (0.6 %). However, unlike the sheets, the yarns contract when the electric potential is applied; this is quite unexpected. The mechanism of this contraction is studied and is related to the insertion of ions in the yarn and the structural changes that take place in the yarn due to its helical twisted structure. A model is presented, relating the actuation strain with yarn geometry (diameter, twist rate, internal packing), electrolyte properties such as ion size, and applied potential. The actuation and mechanical properties of the yarn are studied in various electrolytes. Characterization techniques such as cyclic voltammetry and electrochemical impedance spectroscopy are employed to study the charge storage behaviour of the yarn, showing gravimetric capacitances between 10-60 F/g. It is also shown that the yarns can convert mechanical energy into electrical energy, and are thus capable of measuring mechanical forces. Their behaviour as mechanical force sensors is characterized, showing sensitivities about 2.0±0.6 x 10−⁵ V/MPa. The yarns are superior in work density to piezoelectric actuators when normalized by active material. Creep, can still be an issue, while a tensile modulus of about 16±5 GPa and a tensile strength of about 900 MPa mean that creep is much less than other types of artificial muscles at similar loads. Torsional actuation is also shown to take place if one end of the yarn is free to rotate. Thus, the CNT yarn actuators show the highest achieved stress among polymer artificial muscles and are the first to actuate torsionally, opening a wide range possibilities for applications.
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Sumner, Mark. "Continuous yarn processing systems." Thesis, University of Manchester, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601466.
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The objective of the Engineering Doctorate project was the development of a continuous yam dyeing system which could meet the needs of a changing textile industry. Through an examination of the changes in the industry, it was found that the system must incorporate waste minimisation principles, be flexible and responsive to the demands of the fashion industry and provide the yam dyer with short lead times. Two yam processing systems were identified and investigated to determine whether they could be used to fulfil the aims of the project. The first system was based on the Fibre 'M' Yam Texturing and Dyeing process previously developed at UMIST. The second was a new development referred to as the Sealed Applicator Device (SAD). It had been shown in the past that the Fibre 'M' based system could simultaneously texture and dye polyester yam to a relatively high standard of fixation and bulk. However, through the process investigation presented here it was found that the system lacked flexibility, ease of use and, in addition, its environmental impact could be considerable. The investigation of the SAD process proved to be more fruitful. It was found that the SAD process could be used to impregnate single ends of yam with liquor to a high degree of accuracy and control. Laboratory trials sho~ed that the SAD system could be used to impregnate worsted yam with dye liquor levelly at yam speeds up to 500 m1min at liquor to goods ratios as low as 0.3 : 1. Also it was shown that the SAD system could be used as a high speed yam washing device as well as a yam drying device. Through a combination of the impregnation, washing and drying capabilities of the SAD process, in conjunction with an autoclave stage, it was demonstrated that the SAD process could be used to continuously dye, wash and dry yams at high speed to commercial standards of penetration, levelness and fastness. The potential savings for a yam dyer through the use of the SAD system were explored. It was also shown, through commercial trials, that the SAD system could be used as an integral part of a simultaneous yam folding, setting, conditioning and lubricating process for worsted yams. Comparable levels of setting, conditioning and lubricating to the industry standard were achieved using the SAD process, with the potential for considerable saving for the spinner.
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Goktepe, Fatma. "The effect of yarn structure on the deformation of the yarn cross-section." Thesis, University of Leeds, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416091.
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Hasan, M. M. B., M. Offermann, M. Haupt, A. Nocke, and Ch Cherif. "Carbon filament yarn-based hybrid yarn for the heating of textile-reinforced concrete." Sage, 2014. https://tud.qucosa.de/id/qucosa%3A35610.
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In this study, the application of carbon filament yarn (CFY)-based conductive hybrid yarn as the heating element in a textile-reinforced concrete structure is reported. For this purpose, a hybrid yarn having a core-sheath structure (the core is made of carbon filament yarn and the sheath consists of a mixture of short glass and polypropylene fibres) is manufactured by DREF-2000 spinning technique and integrated into textile structure by tailored fibre placement method. Heat can be generated in the concrete structure by passing electric current through the conductive carbon filament yarn core of the hybrid yarn using the principle of resistive heating, where the sheath acts as the protection and isolation layer. From the initial investigations made on a small concrete specimen, important information is gathered and a large concrete slab with integrated conductive hybrid yarn is manufactured. The heat ability and the comfort level of the manufactured concrete slab are measured. The investigations have revealed the potential of using such hybrid yarn for a pointwise heating of the concrete surface for possible appliance in outdoor furniture.
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Kuganesan, Srijeyanthan. "Distributed Resource Management for YARN." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187044.
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In the last year, Hadoop YARN has become the defacto standard resource management platform for data-intensive applications, with support for a wide range of data analytics platforms such as Apache Spark, MapReduce V2, MPI, Apache Flink, and Apache Giraph. The ResourceManager fulfills three main functions: it manages the set of active applications (Applications service), it schedules resources (CPU, memory) to applications (the FIFO/Capacity/Fair Scheduler), and it monitors the state of resources in the cluster (ResourceTracker service). Though YARN is more scalable and fault-tolerant than its predecessor, the Job-Tracker in MapReduce, its ResourceManager is still a single point of failure and a performance bottleneck due to its centralized architecture. Single point of failure problem of YARN has been addressed in Hops-YARN that provides multiple ResourceManagers (one active and others on standby), where the ResourceManager’s state is persisted to MYSQL Cluster and can quickly be recovered by a standby ResourceManager in the event of failure of the active ResourceManager. In large YARN clusters, with up to 4000 nodes, the ResourceTracker service handles over one thousand heartbeats per second from the nodes in the cluster (NodeManagers), as such become a scalability bottleneck. Large clusters handle this by reducing the frequency of heartbeats from NodeManagers, but this comes at the cost of reduced interactivity for YARN (slower application startup times), as all communication from the ResourceManager to NodeManagers is sent in response to heartbeat messages. Since Hops-YARN is still using a centralized scheduler for all applications, distributing the ResourceTracker service across multiple nodes will reduce the amount of heartbeat messages that need to be processed per ResourceTracker, thus enabling both larger cluster sizes and lower latency for scheduling containers to applications. In this thesis, we will scale-out the ResourceTracker service, by distributing it over standby ResourceManagers using MySQL NDB Cluster event streaming. As such, the distributed Resource Management for YARN that is designed and developed in this project is a first step towards making the monolithic YARN ResourceManager scalable and more interactive.
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Durur, Gungor. "Cross winding of yarn packages." Thesis, University of Leeds, 2000. http://etheses.whiterose.ac.uk/4047/.
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Random winding is widely used for the preparation of yarn packages used in a variety of textile processes. Ribboning caused by overwinding of yarn turns at certain places within the package is a basic problem encountered in this process. Standard random winders incorporate some means of ribbon breaking, which strictly speaking have limited effectiveness. The research reported in thesis was undertaken to realise a random winder capable of detecting the occurrence of ribboning, and taking the ribbon breaking action at these precise times, and thereby achieve 'active' ribbon breaking. Such a winder was realised by the addition of suitable transducers to a standard random winder, which could be controlled by a PC. Winding trials carried out using this equipment established the effectiveness of the concept and also the greater freedom from ribboning the method achieved in comparison with other available methods. Unwinding trials carried out by suitably modifying the winder for measuring yarn unwinding tension were also used to establish the effectiveness of active ribbon breaking. Preliminary experiments carried out on the above apparatus showed the possibility of constructing a Angle of Double Traverse (ADT) diagram on the VDU of the PC during winding operations, which could serve as a useful aid to follow the progress of the winding operation. It was very useful for showing the occurrence of major and minor ribboning in the wound package, and also for visually indicating the effectiveness of the ribbon breaking procedures. The diagram was of further use in studying the nature of package driving by the grooved drum. The case of driving a deformable body such as a yarn package on a comparatively non-deformable grooved drum is important for understanding how the package rotates without any obvious slipping. By varying the winding conditions, it was in fact shown that some measurable slip occurs, and these relationships were experimentally established. Computer simulation is useful to determine the stresses within a wound package, particularly as these cannot be measured using conventional techniques. The results of such a simulation carried out on a random wound package and the comparison of the results with those obtained for a precision wound package are also presented.
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Rajamanickam, Rangaswamy. "Studies on fiber-process-structure-property relationships in air-jet spinning." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/8661.
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Hu, Xiao Ping. "Structure and properties of polyacrylonitrile fibres." Thesis, University of Leeds, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366460.
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Rypl, Rostislav, Rostislav Chudoba, Miroslav Vorechovský, and Thomas Gries. "Evaluation of the Length Dependent Yarn Properties." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-77843.
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The paper proposes a method for characterizing the in-situ interaction between filaments in a multifilament yarn. The stress transfer between neighboring filaments causes the reactivation of a broken filament at some distance from the break. The utilized statistical bundle models predict a change in the slope of the mean size effect curve once the specimen length becomes longer than the stress transfer length. This fact can be exploited in order to determine the stress transfer length indirectly using the yarn tensile test with appropriately chosen test lengths. The identification procedure is demonstrated using two test series of tensile tests with AR-glass and carbon yarns.
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Overington, Y. H. "Aspects of hollow spindle fancy yarn." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556105.
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Knipprath, Christian. "Mechanical performance of binder yarn composites." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/6774.
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This investigation concerns the mechanical response of binder coated carbon tow preforms and laminates. The main focus is on evaluating and modelling the robustness of preforms whilst the methodologies developed are also applied to cured laminates produced using the binder coated preforms. Conventional manufacturing techniques were altered to address the differences in behaviour due to the presence of the binder with the development of infusion schedules. These involve lower temperatures, which eliminate the possibility of binder reactivation during processing. Different development versions of the material in the form of an inhomogeneously or homogeneously bindered tow were characterised in terms of their mechanical response in the preform state. It was observed that the inhomogeneously bindered material had higher modulus and strength in both tension in the fibre direction and shear, while the behaviour of the homogeneous preform is significantly more robust in the transverse to the fibre direction. Laminates produced, using the homogeneously bindered material, were compared to a reference unbindered laminate system, using an aerospace epoxy as a matrix. The out-of-plane properties of the material with binder were superior to the reference laminate, whereas in-plane properties were similar or inferior. The development of models of the mechanical response built around continuum damage mechanics models allowed the simulation of the behaviour of preforms under loading. The implementation of these constitutive models necessitated the development of appropriate parameter estimation techniques capable of solving the inverse problem of identifying the values of 27 material constants that minimise the error between experimental and modelling results. Two novel methodologies were developed and compared to a conventional technique following simplified laminate analysis. The first method performed a gradient-based error minimisation and the second uses the Markov Chain Monte Carlo technique. The gradient-based technique results in a close fit, while this method requires proper definition of the constraints to yield an appropriate solution set. Markov Chain Monte Carlo yields satisfactory results with the additional advantages of overcoming the ill-posedness of the inverse problem without regularisation and providing an output in the form of multivariate probability distributions that can be used directly instochastic simulations. The material parameters obtained and the corresponding constitutive models were used in finite element models of the mechanical response of preforms and laminates. The models were based on the concept of a combination of shell elements representing sub-laminates and cohesive elements simulating the delamination behaviour of interfaces between them. The performance of the models was evaluated using the case of impact of a spar section for preforms and three point bending for the laminates. The agreement between experimental and simulation results was satisfactory. The validated model was used in the context of a design case study based on a helicopter pitch horn component. The aim was to use the results of a draping analysis in the finite element model to evaluate the effects of the assumption of nominal fibre orientations on design and to combine the results of drape optimisation in respect to fibre shear angle with finite element analysis incorporating damage. The results showed that the use of nominal fibre orientation predicts a good performance of the component, whereas the influence of optimising draping on the mechanical performance was inferior.
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Millman, Michael Peter. "Computer vision for yarn quality inspection." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/34196.
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Structural parameters that determine yarn quality include evenness, hairiness and twist. This thesis applies machine vision techniques to yarn inspection, to determine these parameters in a non-contact manner. Due to the increased costs of such a solution over conventional sensors, the thesis takes a wide look at, and where necessary develops, the potential uses of machine vision for several key aspects of yarn inspection at both low and high speed configurations. Initially, the optimum optical / imaging conditions for yarn imaging are determined by investigating the various factors which degrade a yarn image. The depth of field requirement for imaging yarns is analysed, and various solutions are discussed critically including apodisation, wave front encoding and mechanical guidance. A solution using glass plate guides is proposed, and tested in prototype. The plates enable the correct hair lengths to be seen in the image for long hairs, and also prevent damaging effects on the hairiness definition due to yarn vibration and yarn rotation. The optical system parameters and resolution limits of the yarn image when using guide plates are derived and optimised. The thesis then looks at methods of enhancing the yarn image, using various illumination methods, and incoherent and coherent dark-field imaging.
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Demir, Ali. "The air-jet yarn texturing process with particular reference to nozzle design and improved yarn test methods." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/12477.
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Chilo, Marco. "Techniques of meso-scale measurement of fibre assemblies." Thesis, University of Manchester, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.568646.
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The objective of this research project is to investigate novel concepts of determining fibre assembly mechanical properties at woven fabric at meso-scale, viz. yarns and unit-cell. In order to carry out this investigation three instruments were developed and these are presented in subsequent chapters of this thesis. Initially, an instrument was built in order to explore the buckling technique on yarns and fabrics. The data obtained was converted into pure bending output through a proposed non-linear planar elastica model. It was found that the data obtained were in agreement with data obtained from other measuring technique already available in the industry, viz. Pure Bending tester (KES FB2) from the Kawabata Evaluation System. This investigation also found that the buckling technique offers some advantages when compared with the bending tester. Furthermore, the yarn compression method was also explored. A Yarn Compression tester (YCT) was developed in order to carry out this study. This instrument induces transverse compression upon the yarn by means of a probe, which results in a compression versus thickness curve. An, additional feature was introduce on the YCT, such as the use of a digital camera that allows the yarn lateral spreading to be determined as the yarn is compressed. This feature may be used to calculate the Poisson’s ratio, which can be used as an input value for future compression models. Good agreement was found between the proposed yarn compression technique and data obtained from the Kawabata compression tester.Finally, yarn torsional technique was explored by means of developing a Yarn Torsion tester (YTT). It was found that data obtained for this instrumentation were in agreement with a linear model proposed by Postle et al. This investigation may allow future research to continue by means of proposing a torsion mathematical model.
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Tang, Nelson K. H. "The design and construction of a prototype yarn brushing machine to produce novel brushed yarns." Thesis, University of Huddersfield, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292286.
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Smigielski, Edward. "The effect of batch yarn felting on the properties of wool carpets and carpet yarns." Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327778.
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Fellague-Ariouat, Abdelkader. "Design and analysis of primary heaters for false-twist texturing machines." Thesis, Queen Mary, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339193.
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Dehghani, Sanij Abbas A. "An appraisal of the autolevelling systems and of the methods needed to assess their behaviour." Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.352984.
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Ok, Hyunyoung. "Single end sizing of yarn using a slot applicator." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/8653.
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Allen, Keith John. "Friction spinning : an investigation of yarn formation." Thesis, Loughborough University, 1991. https://dspace.lboro.ac.uk/2134/27571.
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Friction spinning is a relative newcomer to textile technology. It has generated great interest because of its potential for wide application of certain problems regarding the quality of yarn produced at high output rates can be solved. General acceptance of the process is hindered by uncertainty as to its capability of producing yarns of sufficient strength at speeds greater than 300 m/min. (NB: as a guide, maximum output rates of competitive technologies are no more than 150 m/min.) Friction spinning appears to have no intrinsic self-limit to its maximum output rate, unlike ring and rotor spinning which are limited by centrifugal effects leading to excessive yarn breakages. The process will therefore provide something of a quantum leap in output if acceptable yarn quality is achieved.
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Andersson, Robin. "GPU integration for Deep Learning on YARN." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-222357.
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In recent years, there have been many advancements in the field of machine learning and adoption of its techniques in many industries. Deep learning is a sub-field of machine learning that is largely attributed to many of recent innovative applications such as autonomous driving systems. Training a deep learning model is a computationally intensive task that in many cases is inefficient on a CPU. Dramatically faster training can be achieved by making use of one or more GPUs, coupled with the need to train more complex models on increasingly larger datasets, training on a CPU is not sufficient. Hops Hadoop is an Hadoop distribution that aims to make Hadoop more scalable, by migrating the meta-data of YARN and HDFS to MySQL NDB. Hops is currently making efforts to support distributed TensorFlow. However, GPUs are not currently managed natively by YARN, therefore, in Hadoop, GPUs cannot be scheduled to applications. That is, there is no support for isolating GPUs to applications and managing access to applications. This thesis presents an architecture for scheduling and isolating GPUs-as-aresource for Hops Hadoop. In particular, the work is constrained to supporting YARN’s most popular scheduler, the Capacity Scheduler. The architecture is implemented and verified based on a set of test cases. The architecture is evaluated in a quantitative approach by measuring the performance overhead of supporting GPUs by running a set of experiments. The solution piggybacks GPUs during capacity calculation in the sense that GPUs are not included as part of the capacity calculation. The Node Manager makes use of Cgroups to provide exclusive isolation of GPUs to a container. A GPUAllocator component is implemented that keeps an in-memory state of currently available GPU devices and those which are currently allocated locally on the Node Manager. The performance tests concluded that the YARN resource model can be extended with GPUs, and that the overhead is negligible. With our contribution of extending Hops Hadoop to support GPUs as a resource, we are enabling deep learning on Big Data, and making a first step towards support for distributed deep learning.De senaste åren har många framsteg gjorts inom maskininlärning och användning av dess tekniker inom många olika industrier. Djupinlärning är ett delområde inom maskininlärning som är hänförlig till många av de senaste innovativa applikationerna såsom system för autonom bilkörning. Att träna en djupinlärningsmodell är en beräkningsmässigt intensiv uppgift som i många fall är ineffektivt på endast en processor. Dramatiskt snabbare träning är möjlig genom att använda en eller flera grafikkort, kopplat med behov att träna mer komplexa modeller med större datamängder, är det inte hållbart att endast träna på en processor. Hops Hadoop är en Hadoop distribution med målet att göra Hadoop mer skalbart, genom att migrera metadata från YARN och HDFS till MySQL NDB. Hops utför i nuläget ett arbete med att stödja distribuerad TensorFlow. För närvarande finns inget stöd för grafikkort som en resurs i YARN, därmed, i Hadoop, så kan grafikkort inte schemaläggas för applikationer. Mer specifikt, det finns inget stöd för att isolera grafikkort för applikationer och erbjuda som en resurs. Den här uppsatsen presenterar en arkitektur för att schemalägga och isolera grafikkort som en resurs i Hops Hadoop. Arbetet innefattar stöd för den mest populära schemaläggaren i YARN, kapacitets schemaläggaren. Arkitekturen implementeras och verifieras utifrån en mängd testfall. Arkitekturen utvärderas sedan i ett kvantitativt tillvägagångssätt genom att mäta tidspåverkan att stödja grafikkort genom att utföra ett antal experiment. Lösningen tar inte hänsyn till grafikkort som en del av kapacitetsberäkningen. Node Manager komponenten använder Cgroups för att utföra isolering av grafikkort. En GPUAllocator komponent har implementerats som håller ett tillstånd över vilka grafikkort som allokerats och vilka som är lediga på Node Manager. Experimenten konkluderar att YARN kan stödja grafikkort som en resurs och att tidspåverkan för detta är försumbart. Detta arbete med att stödja grafikkort som en resurs på Hops Hadoop, gör det möjligt att utföra djupinlärnin på stora datamängder, och är ett första steg mot stöd för distribuerad djupinlärning.
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Ho, Ping-Wing. "Discrete event simulation for yarn manufacturing processes." Thesis, University of Huddersfield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315679.
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BERTOCCHI, Giorgio. "Modellazione e criteri di sintesi di alimentatori di filato." Doctoral thesis, Università degli studi di Bergamo, 2011. http://hdl.handle.net/10446/873.
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Srinivasan, K. V. "A study of the principles of hollow spindle wrap spinning." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556204.
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Ilett, Stephen John. "Investigation of the package dyeing process using a fixed bed reactor as a model system." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236872.
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Oener, Erhan. "Thermal characterization of polyester/cellulosic blended materials." Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329259.
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Miao, Menghe. "The insertion of twist into yarns by means of air-jets." Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329209.
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Guo, Mingzhi. "A re-examination of twisting systems in false-twist texturing." Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329207.
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Tandon, Surinder Kumar. "Deformations of helical fibres under uniformly and non-uniformly distributed compressive forces." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235516.
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Holdstock, Christine Ruth. "The measurement and control of dyebath exhaustion." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328322.
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Cassidy, T. "The measurement of woollen card web weight per unit area variation by the obscuration of light." Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234906.
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Romanyuk, V. P. "The trends of knitwear market in Ukraine." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/14388.
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Fassihi, Ali Akbar. "The further development, optimisation and application of a Yarn Dismantler." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1016066.
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The fibre properties of cotton, which vary widely according to genetic and environmental conditions, determine its price and textile processing performance and product quality. It is therefore hardly surprising that cotton fibre properties are routinely measured for trading and quality control purposes, with a great deal of research having been, and still being, devoted towards developing instruments which enable the various fibre properties to be measured rapidly and accurately. In many cases, it is also necessary to be able to measure properties of cotton fibres when they have already been converted into yarn and fabric form. To do so, the yarn has to be dismantled into its component fibres, preferably without significantly changing the fibre properties. This could only be done by manually untwisting the yarn and carefully extracting the fibres from the untwisted yarn, care being taken not to break or lose any fibres in the process. This is a time consuming, laborious and labour intensive process. In view of this, a „yarn dismantler‟ which could automatically, cost effectively and within acceptable time frames, dismantle a cotton yarn into its constituent fibres, without undue damage or changes to the fibres, was developed and patented. This thesis reports the results of research undertaken to further develop, evaluate and optimize the yarn dismantler into the final prototype, as well as those relating to its practical applications, including tracking changes in fibre properties during miniature and pilot scale processing, up to, and including the yarn stage. Initial research undertaken on the original bench and first prototype models indicated that, although they produced very promising results, certain improvements and modifications were necessary, if the dismantler was to perform in an efficient and operator friendly manner at the required speeds. These included changes in the axial position of the untwisting spindle and the perforated screen of the suction drum, increasing the air suction at the perforated drum, installing a new motor for the untwisting spindle drive, separating the drives to the different parts of the unit in order to control them independently, integrating a more effective steaming unit into the unit etc. It was found that the dismantling rate had to be set to equal about 95 percent of the original twist in the yarn, and that steaming of the dismantled (untwisted) yarn on the perforated drum was necessary in order to eliminate any twist liveliness (residual torque) in the dismantled yarn, and enable it to be handled and tested on the AFIS instrument. When the final prototype Yarn Dismantler was produced, incorporating all the above mentioned improvements, it functioned very well at dismantling speeds of at least 2m/min, enabling the length of yarn required for subsequent AFIS testing to be dismantled within an acceptable time of less than 10 minutes, with excellent reproducibility and repeatability of results, also under commercial conditions. It was found that the AFIS measured length characteristics of fibres from the instrument dismantled yarns compared very well with those of fibres from manually dismantled yarns, differences in fibre length generally being less than 1mm, and it was concluded from these and other evaluation tests, that the yarn dismantler produced fibres without any significant fibre breakage. Some limited tests, carried out on commercially produced carded and combed yarns, indicated that short fibre content and dust and trash levels, as measured by the AFIS on fibres from dismantled yarn, together with the corresponding Uster Statistics, could enable a carded cotton yarn to be distinguished from a combed cotton yarn. Statistical analysis of fibre test results obtained at the different stages during miniature and pilot plant scale processing of various cottons, clearly showed that very significant changes in fibre properties could be caused by certain of the processes. For example, significant fibre breakage occurred during the drafting on the spinning frame, prior to twist insertion. The thesis provides detailed results of changes in various fibre properties, including length, short fibre content, maturity, immature fibre content, seed coat neps and fibrous neps, which occurred from the lint to the final yarn, as well as on the relationship between the properties of the fibres from the dismantled yarn and those from the lint. The results obtained have clearly demonstrated the practical value of the yarn dismantler in enabling yarns to be automatically dismantled into their constituent fibres, which can then be tested by an instrument, such as the AFIS, and the test results related to those of the original lint fibres, thereby opening up many fields of research and practical applications, some of which are captured under „Recommended Further Work‟.
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Nartetamrongsutt, Kitchaporn. "Modification of Electrospinning Solutions and Yarn Production for Filtration Application." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1375274887.
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Atalay, Ozgur. "Development and investigation of weft knitted strain sensor." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/development-and-investigation-of-weft-knitted-strain-sensor(54fffacb-d1d7-4e9e-9d8f-7f33d4b90d66).html.
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This thesis presents a study of the sensing properties exhibited by textile-based knitted strain sensors. Sensing fabrics were manufactured from silver-plated conductive nylon and non-conducting elastomeric yarns. The component yarns offered similar diameters, bending characteristics and surface friction, but their production parameters differed in respect of the yarn input tension, the number of conductive courses in the sensing structure and the elastomeric yarn extension characteristics. The knitted sensors were manufactured using flat-bed knitting technology, and electro-mechanical tests were performed on the specimens using a tensile testing machine to apply strain whilst the sensor was incorporated into a Wheatstone bridge arrangement to allow electrical monitoring. The novel operational principle relies on the separation under strain of adjacent conducting knitted loops which are normally held in contact by the elastomeric yarn. The results confirm that production parameters play a fundamental role in determining the physical behaviour and the sensing properties of knitted sensors and the response could be engineered by varying the production parameters of specific designs. Results showed that the knitted structures could be manipulated to produce gauge factor values between 2.26 and 0.23 for sensors with working ranges of 8.4 % and 3.3 % respectively when the elastomeric yarn had 8 cN input tension. The generated signals were stable and repeatable, and under cyclic testing proved to be substantially free from long-term drift. A textile-based strain sensor was developed to create a respiration belt; this was realised by bringing together the extensible knitted sensor and a relatively inelastic textile strap. Machine simulations and real time measurements on a human subject were performed to calculate average breathing frequencies under different static and dynamic conditions. Various respiration rates were monitored to simulate different medical conditions and with the belt located either round the torso or in the abdominal area, the sensor yielded a satisfactory response. However, body motion artefacts affected the signal quality under dynamic conditions and an additional signal-processing step was added to separate unwanted interference from the breathing signal. Electro-mechanical modelling was developed by exploiting Peirce`s loop model in order to describe the fabric geometry under static and dynamic conditions. Kirchhoff`s node and loop equations were employed to create a generalised solution for the equivalent electrical resistance of the textile sensor for a given knitted loop geometry and for a specified number of loops. Experimental results were obtained from the sensor for strain levels up to 40% and these correlate well with the modelled data; a maximum error of 2.13 % was found between the experimental and modelled resistance-strain relationships.
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Souza, Clara Silvestre de. "Varia??o de temperatura e umidade e suas influ?ncias nas caracter?sticas f?sicas e mec?nicas dos fios de algod?o." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15715.
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Cotton is a hydrofilic textile fiber and, for this reason, it changes its properties according to the environment changes. Moisture and Temperature are the two most important factors that lead a cotton Spinning sector and influence its quality. Those two properties can change the entire Spinning process. Understanding this, moisture and temperature must be kept under control when used during the Spinning process, once the environment is hot and dry, the cotton yarns absorb moisture and lose the minimal consistency. According to this information, this paper was developed testing four types of cotton yarns, one kind of cotton from Brazil and the others from Egypt. The yarns were exposed to different temperatures and moisture in five different tests and in each test, six samples that were examined through physical and mechanical tests: resistance, strength, tenacity, yarn?s hairness, yarn?s evenness and yarn?s twisting. All the analysis were accomplished at Laborat?rio de Mec?nica dos Flu?dos and at COATS Corrente S.A., where, it was possible to use the equipments whose were fundamental to develop this paper, such as the STATIMAT ME that measures strength, tenacity, Zweigler G566, that measure hairiness in the yarn, a skein machine and a twisting machine. The analysis revealed alterations in the yarn?s characteristics in a direct way, for example, as moisture and temperature were increased, the yarn?s strength, tenacity and hairness were increased as well. Having the results of all analysis, it is possible to say that a relatively low temperature and a high humidity, cotton yarns have the best performance
O algod?o ? uma fibra t?xtil hidr?fila e por essa raz?o muda suas caracter?sticas em fun??o das condi??es do ambiente. A umidade e a temperatura s?o dois fatores que influenciam o ambiente de uma fia??o de algod?o. Estes dois fatores podem alterar a qualidade de toda uma produ??o de fios. Sendo assim, umidade e temperatura devem ser mantidas sob o controle para o processamento do algod?o, uma vez que em um ambiente seco e quente os fios de algod?o liberam umidade e se rompem, aumentando o ?ndice de quebra da fia??o com o ambiente frio e ?mido, os fios absorvem umidade e perdem a consist?ncia m?nima.Com base nessas informa??es, este trabalho foi desenvolvido experimentando quatro tipos de fio de algod?o sendo de origem brasileira e os demais, de origem eg?pcia. Os fios foram expostos a temperatura e umidade diferentes em cinco experimentos distintos, contendo cada experimento seis amostras que passaram por testes f?sicos e mec?nicos: resist?ncia, for?a, tenacidade, pilosidade, t?tulo e tor??o. As an?lises foram realizadas no Laborat?rio de Mec?nica dos Fluidos na Universidade Federal do Rio Grande do Norte e na empresa COATS Corrente S.A., onde foi poss?vel fazer uso dos equipamentos fundamentais para o desenvolvimento deste trabalho, tais como o STATIMAT ME que mede a resist?ncia, for?a e tenacidade do fio, Zweigler G566 o qual mensurou a quantidade de pilosidade no fio e, a meadeira e o torc?metro, respons?veis pelo t?tulo e tor??o. As an?lises revelaram altera??es nas caracter?sticas dos fios de forma diretamente proporcional, como por exemplo, conforme aumentava-se a umidade e temperatura havia um aumento da resist?ncia, for?a, tenacidade e pilosidade. Em posse desses resultados, ? poss?vel afirmar que a uma temperatura relativamente baixa e uma umidade alta, os fios de algod?o tem sua performance m?xima
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Kakantousis, Theofilos. "Scaling YARN: A Distributed Resource Manager for Hadoop." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177200.
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In recent years, there has been a growing need for computer systems that are capable of handling unprecedented amounts of data. To this end, Hadoop HDFS and Hadoop YARN have become the de facto standard for meeting demanding storage requirements and for managing applications that can process this data. Although YARN is a major advancement from its predecessor MapReduce in terms of scalability and fault-tolerance, its Resource Manager component that performs resource allocation introduces a potential single point of failure and a performance bottleneck due to its centralized architecture. This thesis presents a novel architecture in which the Resource Manager runs on a distributed network of stateless commodity machines as its state is migrated to MySQL Cluster, a relational write-scalable and highly available in-memory database. By doing so, the Resource Manager becomes more scalable as it can now run on multiple nodes as well as more fault-tolerant as arbitrary node failures do not result in state loss. In this work we implemented the proposed architecture for the Resource Tracker service which performs cluster node management for the Resource Manager. Experimental results validate the correctness of our proposal, demonstrate how it scales well by utilizing stateless Resource Manager machines and evaluate its performance in terms of request throughput, system resource and database utilization.
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Rashid, Zahin Azher. "Intelligent Scheduling for Yarn : Using Online Machine Learning." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-219607.
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Many big companies who provide cloud infrastructure, platforms and services have to face a lot of challenges in dealing with big data and execution of thousands of tasks that run on servers. Thousands of servers running in cloud consume a large amount of energy which increases operating cost to a great extent for companies hosting infrastructures and platforms as services. Hundreds of thousands of applications are submitted every day on these servers by users. On submission of applications, somehow the total resources are not properly utilized which cause the overall operating cost to increase. A distribution of Apache Hadoop called HOPS is developed at SICS Swedish ICT and efforts are made to make it a better platform for institutions and companies. Yarn is used as the resource management and scheduling framework which is responsible for allocating resources such as memory and CPU cores to submitted applications. Yarn simply allocate resources based on the default set of values or what user has demanded. Yarn has no prior information about the submitted applications so it is very much possible that allocated resources are more or less than required. Energy is being wasted if fewer resources are required or application will probably not succeed if required more. In this research project, different techniques and methods are looked into for the collection of useful metrics related to applications and resources from Yarn, Spark and other sources. Machine Learning is becoming a very popular technique nowadays for the optimization of systems dealing with big data in a cloud environment. The goal is to collect these vital metrics and build a machine learning model to commission smart allocation of resources to submitted applications. This can help to increase the efficiency of the servers in the cloud and reduce the operating cost. Finally, a machine learning model was developed and memory and vCores were successfully predicted to be allocated to applications.Många stora företag som tillhandahåller molninfrastruktur, plattformar och tjänster måste möta många utmaningar när det handlar om stora data och utförandeav tusentals uppgifter som körs på servrar. Tusentals servrar som kör i molnetförbrukar en stor mängd energi vilket i hög grad ökar driftskostnaden för företag som tillhandahåller infrastrukturer och plattformar som tjänster. Hundratusentals applikationer skickas varje dag på dessa servrar av användare. Vid inlämning av ansökningar på något sätt utnyttjas inte de totala resurserna korrekt, vilket medför att de totala driftskostnaderna ökar. En distribution av Apache Hadoop, kallad HOPS, är utvecklad hos SICS Swedish ICT, och det görs ansträngningar för att göra den till en bättre plattform för institutioner och företag. Garn används som resurshanteringsoch schemaläggningsramen som är ansvarig för att allokera resurser som minne och CPU-kärnor till inlämnade applikationer. Garn fördelar helt enkelt resurser utifrån standardvärdet av värden eller vilken användare som har krävt. Garn har ingentidigare information om de inlämnade ansökningarna så det är mycket möjligtatt tilldelade resurser är mer eller mindre än vad som krävs. Energi slösas bort om färre resurser krävs eller ansökan kommer sannolikt inte att lyckas om det behövs mer. I detta forskningsprojekt undersöks olika tekniker och metoder för insamling av användbara mätvärden relaterade till applikationer och resurser från Garn, Spark och andra källor. Machine Learning blir idag en mycket populär teknik för optimering av systemsom hanterar stora data i en molnmiljö.Målet är att samla in dessa viktigamätvärden och bygga en maskininlärningsmodell för att beställa smart fördelning av resurser till inlämnade applikationer. Detta kan hjälpa till att öka effektiviteten hos servrarna i molnet och minska driftskostnaden. Slutligen utvecklades en maskininlärningsmodell och minnet och vCores hade framgångsrikt förutsagt att tilldelas applikationer.
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Sun, XingXian. "Technology and economics of sizing single worsted yarn." Thesis, University of Huddersfield, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307839.
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Bazbouz, Mohamed Basel. "An investigation of yarn spinning from electrospun nanofibres." Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2245.
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The aim of the thesis is to investigate yarn spinning from electrospun nanofibres. The concepts of staple and core yarn spinning on electrospun nanofibres has been investigated by examining nanofibre uniformity, alignment, twist insertion and yarn take up by engining and engineering a new take up mechanism. Nylon 6 nanofibres have been fabricated and used throughout this work. The effects of varying the electrospinning parameters such as applied voltage, polymer solution concentration and electrospinning distance on fibre morphology have been established for process optimization. A novel nanofibre aligning mechanism has been devised and systematically revised to enable optimization of alignment process parameters. MWCNTs have been successfully dispersed into nylon 6 nanofibres and have been aligned along the nanofibre body by manipulating the electric and stretching forces with the aid of the alignment mechanism. Novel mechanisms for spinning continuous twisted nanofibre/composite nanofibre yarn and core electrospun yarn have been researched, developed and implemented by making samples. It has been found that defining the velocity and count of the nanofibres entering the spinning zone is important for controlling the yarn count and twist per unit length. By modelling the electrospinning jet, mathematical equations for theoretically calculating the velocity of the jet and nanofibres and their count have been established, necessary for process control. Aspects of practical measurement and comparison of jet and nanofibre velocities have been described and discussed. Tensile testing of single nanofibre and nanofibre mats has been attempted for mechanical characterization. Initial results show the range of tensile strength of nylon 6 nanofibre assemblies and indicate the effect of change of process parameters. A review of those engineering mechanisms related to various nanofibre architectures and their industrial and commercial importance has also been reviewed, described and discussed.
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Alshukur, Malek. "On the structure of multi-thread boucle yarn." Thesis, Heriot-Watt University, 2017. http://hdl.handle.net/10399/3362.
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This research had two dimensions. The first one was theoretical and the geometry of doubled fancy yarn, including bouclé yarn, was modelled mathematically. As a result, the length of the effect component that is necessary to make a copy of those types of fancy yarn was estimated. Further, a geometrical model for the width of the effectthread helices in the First Spinning Zone was presented. One important benefit of this model was using it to control the structure of the bouclé yarn and to prevent the formation of faults and loops on the bouclé yarns. The second dimension was experimental. The mathematical, geometrical model of doubled fancy yarn was tested and the coefficient of correlation between the predicted values and the actual values was r=0.90. This was accomplished by providing methods and roadmaps to help making copies of the bouclé and semi-bouclé fancy yarns after using the output of the geometrical model of the structure. Further, it was found that the technological factors which affected the bouclé yarn structure and geometry were the bending stiffness of the effect thread(s), the rotational speed of the hollow spindle, the level of Tension of the core thread, the overfeed ratio, the number of wraps, and the interaction between those factors. Furthermore, when narrow effect helices have formed in the First Spinning Zone, the thickness of the effect thread was as important as its bending stiffness. To measure the bending stiffness of the input threads, the Beam Method was applied using a simple apparatus, called the Bending Frame, which was built for this purpose.
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Webb, Carwyn James. "Investigation and modelling of the yarn splicing process." Thesis, University of South Wales, 2008. https://pure.southwales.ac.uk/en/studentthesis/investigation-and-modelling-of-the-yarn-splicing-process(b153a874-d572-4b08-a047-e7b13741d65a).html.
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The pneumatic splicing technique was developed in the 1960's to overcome the deficiencies of knotting of textile yarns, but there has been little research into splicing because it is a complicated process, very difficult to observe. A splice is formed very quickly, using highly turbulent air within a closed environment. Direct observation is almost impossible. The poor understanding of the mechanism has led to ad-hoc solutions, and can yield unpredictable splice characteristics. A better understanding of the splicing process is long overdue. The objective of the research is the evolution of a theoretical model which would offer a better understanding of the splicing process than existing models, and which would be capable of being used as a predictive design tool for future splicers. The research programme presented in this thesis demonstrated the feasibility and efficiency of the Taguchi design of experiment method, as applied to the splicing process. The Taguchi method simplified the research, and facilitated the identification of the design parameters most relevant to splice quality. Mechanical aspects of experimental splicers were altered to establish how design features affect splicing performance. The effects of commonplace process parameters such as air pressure and blast duration were examined in detail. These experiments demonstrated the importance of air mass flow rate as a fundamental parameter in splicing; they also revealed the existence of a phenomenon which was called "scaling". Scaling describes the change in performance of a splicer, when it is confronted with yarns of a size which are outside its normal envelope of performance. Other techniques were used in conjunction with Taguchi; these included flow visualisation, computational fluid dynamics simulations, and the use of scanning electron microscopes. These approaches have been used together, to optimise splicer parameters and to investigate the airflow within the splicing chamber - the component which ultimately determines the splice structure. These techniques were also used to model the airflow within a wide range of commercially available splicing chambers. The validity of the visualisation and simulation methods are discussed, and a degree of confidence in the accuracy of the outcomes is established. By combining simulation images with the conventional experimental results, it was possible to develop an improved theoretical model for the splicing process. The model proved sufficiently robust to explain a number of phenomena in splicing previously poorly understood. The new model has been used as a prediction tool for splicer design characteristics. It is likely that the model will permit the creation of a new generation of high-performance splicing tools.
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Rendleman, Susan Ruth. "Handweavers' enduring product involvement with craft yarns and selected information processing variables." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-06112009-063405/.
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He, Jingwu. "The role of yarn structure on the hand related low-stress mechanical behavior of enzyme treated yarns by Jingwu He." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/9491.
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Yadav, Vijay Kumar. "Application of signal processing techniques for characterisation and monitoring of yarn faults." Thesis, IIT Delhi, 2016. http://localhost:8080/xmlui/handle/12345678/7063.
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