Dissertations / Theses: 'Separation of waste at source'

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Kwok, Ying-pui, and 郭英佩. "Domestic municipal solid waste source separation in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31254251.

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Kwok, Ying-pui. "Domestic municipal solid waste source separation in Hong Kong /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21301724.

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Nemat, Babak. "Elucidating the Influence of Food Packaging Attributes on Source-separation of Food Packaging Waste at Home." Licentiate thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-24007.

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The global amount of waste generated by households, including food packaging waste, has been increasing continuously across the world, posing a massive threat to societies and the environment. Proper waste management, therefore, has become a challenging environmental issue and a priority for governments. Along with the technological advances, such as material recovery technologies, more stress has been placed on the strategies for moving away from disposal to waste prevention, separation, and recycling. Considerable efforts are being made to not only limit the overall production and the negative impact of waste on the environment and human health but also to minimize the cost of waste management. Separation of wastes at the source (i.e., source separation) is an integral part of such efforts toward enhancing the purity of collected waste and improving the quality of materials for recycling. Furthermore, sorting of waste as a habitual performance can serve as a practice for improving residents' recycling/sorting behavior. The packaging waste, including food packaging, forms a significant part of the municipal solid waste. The design of food packaging, therefore, has received a lot of attention as a useful tool to influence the consumers' sorting behavior, making it an interesting concept for research related to waste management. Presumably, the design of food packaging can meet consumers' sorting demands while being instructive and facilitating the sorting process, thus enhancing the recycling rate of the food packaging waste. Finding the ideal form of food packaging, however, requires an in-depth understanding of the packaging-consumer interactions throughout the sorting process. Considering the different characteristics of food packaging, it is expected that different food packages tend to influence a consumer in different ways. Nevertheless, the current knowledge is somewhat too general to be used by packaging developers to improve the sorting of the food packaging. Hence, the present thesis aims to provide a more in-depth insight into the influence of food packaging, as a product and service provider, on the consumer's/user's decision-making on sort of food packaging waste. The results assert that packaging to be sorted properly requires proper design to manifest its sorting related abilities such as easy to empty, easy to clean, and easy to fold, for the consumer. Selecting material, visual attributes, form, and function can amplify or reduce these sorting abilities of food packaging.

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Altundal, Sadiye, and Meloujane Gullberg. "En fallstudie om hushållens källsortering i Augustenborg (A Case Study on Waste Management in Augustenborg)." Thesis, Malmö högskola, Fakulteten för teknik och samhälle (TS), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23418.

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Hållbar utveckling är en vision som hela världen eftersträvar att uppnå. Hushållsavfallshanter-ing är ett sätt för att uppnå en hållbar samhällsutveckling. Bra kunskap, information och sam-verkan mellan olika aktörer är ytterst nödvändigt för att kunna uppnå en hållbar samhällsut-veckling. Syftet med fallstudiet är att kartlägga en del av stadsdelen Augustenborg i Malmö för att se över hur hushållsavfallshantering fortskrider. Det är även vårt syfte att identifiera möjligheter och hinder för en ökad källsortering i området. Genom enkätundersökning och intervjuer har vi samlat information om hur olika faktorer påverkar avfallshantering i Augus-tenborg. Resultatet visar att det finns olika faktorer som påverkar avfallshanteringssystemet och dessa är inte bara det formella faktorer som till exempel regler och lagar men också andra faktorer som människans attityder har stor betydelse.
Sustainable development has become a major concern all over the world. Household waste management is one of the solutions to attain a sustainable development and community. It is today of great importance to have the proper knowledge, information and coordination be-tween different sectors and organizations in order to attain a sustainable development. This case study aims to investigate an area in Augustenborg, Malmö in order to analyze their existing waste management system. It is even our intention to identify the development pos-sibilities and obstacles of waste management in the area. Through survey and personal inter-views, we were able to gather information on different factors and variables that affect waste management system in Augustenborg. The results suggest that there are various factors that affect waste management, and these are not just formal factors, such as rules and regulations but also other factors, such as human behaviour.

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Pietikäinen, Vivi. "Look beyond the bin! : Solid Waste Management and recycling at the Asian Institute of Tecnology." Thesis, Södertörn University College, School of Life Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-1972.

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The generation of domestic waste is at present less than 1 kg/day per person in Thailand, but generated amounts keeps steadily growing. This trend is closely connected to an increasing population and economic growth, something that is creating waste management issues. The Asian Institute of Technology (AIT) outside Bangkok has the potential of being a leader in sustainable development in the Southeast Asian region, however a substantial opportunity is being missed – best environmental practices are currently not prioritized. Only 4 % of the total waste generated on campus is recycled at AIT, 3 % is composted and 93 % is taken to the municipal waste disposal site. Fluorescent light bulbs and other hazardous household waste are disposed on the campus dumpsite. Some measures have been undertaken in order to improve the solid waste management (SWM) at AIT, e.g. a new waste collection facility has been built in the outskirts of campus, where more space is provided in order to facilitate waste separation.

The field research for this study was carried out at AIT and the goal was to examine the SWM network, the problems and to analyse the recycling habits on campus. To investigate and visualize the actors involved in the SWM at AIT, the Actor-Network theory (ANT) was applied as an analytical framework. The generation of waste is the macro actor i.e. the reason for the existence of SWM. Other actors are the AIT students and staff (produce waste), the new Campus Environment and Development Committee – CEDC (the controlling part), environmental awareness (attitude towards recycling), and waste collectors.

The results from the survey witness of that people have a positive but somewhat cautious attitude towards the sustainability of source separation. Separating waste at source is a key mechanism for solving the SWM problem but people are uncertain of how to separate each waste fraction. There is a strong need to designate a coordinator of the SWM at AIT and as long as there is a lack of leadership, a goal of environmentally sustainable practices cannot be reached. The new CEDC is currently not performing any actions towards an integrated SWM.

Idag produceras mindre än ett kilo hushållsavfall per dag och person i Thailand men mängden växer stadigt med ökad befolkning och bättre ekonomiska förutsättningar vilket leder till sophanteringsproblem. Asian Institute of Technology (AIT) i Thailand har potential att vara en ledstjärna inom hållbar utveckling i Sydostasien men en stor möjlighet går om intet – den bästa miljömässiga tillämpningen i sophanteringsfrågan prioriteras inte. Endast 4 % av soporna återvinns på AIT, 3 % komposteras och 93 % hamnar på den kommunala soptippen. Lysrör och annat farligt hushållsavfall dumpas på universitetets soptipp. Vissa åtgärder har vidtagits för att förbättra sophanteringen på AIT, t.ex. har en ny sopanläggning byggts i utkanten av campus med ökad kapacitet för sopsortering.

Fältarbetet för uppsatsen genomfördes på AIT och målet var att kartlägga sophanteringen, nätverket kring den, problemen runtom, samt att analysera återvinningsbeteendet på detta universitetscampus. För att gestalta och utreda aktörerna som är involverade i sophanteringen på AIT, använde jag Actor-Network theory som ett analytiskt verktyg. Själva produceringen av hushållssopor är makroaktören, dvs. skälet till sophanteringens existens. Andra aktörer är studenterna och de anställda på universitetet (skapar sopor), den nya kommittén för Miljö och Utveckling på campus (den kontrollerande delen), miljömedvetenhe (inställningen till återvinning) och sophämtarna.

Resultaten från enkätunderökningen vittnar om att människorna har en positiv men försiktig inställning gentemot hållbarheten i källsortering. Källsortering är grunden för att lösa sophanteringsproblematiken men folk är osäkra på hur de ska sortera avfallet. Det finns ett stort behov av en avfallshandläggare för sophanteringen på AIT och så länge bristen på ledarskap kvarstår, kan inte målet om miljömässig hållbarhet nås. Den nya kommittén för Miljö och Utveckling på campus genomför för tillfället inga handlingar i riktning mot en integrerad sophantering.

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Martinsson, Erik, Emil Martinsson, and Sören Säf. "IWESS, an integrated water, energy and sanitation solution : A holistic approach to reach sustainability trough organic waste management for the Lake Victoria Basin, Kenya." Thesis, University of Skövde, School of Technology and Society, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-566.

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The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies.

The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits.

The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials.

The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality.

The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.

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Karlsson, Ulrika. "Environmental levels of thallium : Influence of redox properties and anthropogenic sources." Doctoral thesis, Örebro : Örebro universitetsbibliotek, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-356.

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Gunawan, David Oon Tao Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Musical instrument sound source separation." Awarded By:University of New South Wales. Electrical Engineering & Telecommunications, 2009. http://handle.unsw.edu.au/1959.4/41751.

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The structured arrangement of sounds in musical pieces, results in the unique creation of complex acoustic mixtures. The analysis of these mixtures, with the objective of estimating the individual sounds which constitute them, is known as musical instrument sound source separation, and has applications in audio coding, audio restoration, music production, music information retrieval and music education. This thesis principally addresses the issues related to the separation of harmonic musical instrument sound sources in single-channel mixtures. The contributions presented in this work include novel separation methods which exploit the characteristic structure and inherent correlations of pitched sound sources; as well as an exploration of the musical timbre space, for the development of an objective distortion metric to evaluate the perceptual quality of separated sources. The separation methods presented in this work address the concordant nature of musical mixtures using a model-based paradigm. Model parameters are estimated for each source, beginning with a novel, computationally efficient algorithm for the refinement of frequency estimates of the detected harmonics. Harmonic tracks are formed, and overlapping components are resolved by exploiting spectro-temporal intra-instrument dependencies, integrating the spectral and temporal approaches which are currently employed in a mutually exclusive manner in existing systems. Subsequent to the harmonic magnitude extraction using this method, a unique, closed-loop approach to source synthesis is presented, separating sources by iteratively minimizing the aggregate error of the sources, constraining the minimization to a set of estimated parameters. The proposed methods are evaluated independently, and then are placed within the context of a source separation system, which is evaluated using objective and subjective measures. The evaluation of music source separation systems is presently limited by the simplicity of objective measures, and the extensive effort required to conduct subjective evaluations. To contribute to the development of perceptually relevant evaluations, three psychoacoustic experiments are also presented, exploring the perceptual sensitivity of timbre for the development of an objective distortion metric for timbre. The experiments investigate spectral envelope sensitivity, spectral envelope morphing and noise sensitivity.

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Gao, Bin. "Single channel blind source separation." Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1300.

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Single channel blind source separation (SCBSS) is an intensively researched field with numerous important applications. This research sets out to investigate the separation of monaural mixed audio recordings without relying on training knowledge. This research proposes a novel method based on variable regularised sparse nonnegative matrix factorization which decomposes an information-bearing matrix into two-dimensional convolution of factor matrices that represent the spectral basis and temporal code of the sources. In this work, a variational Bayesian approach has been developed for computing the sparsity parameters of the matrix factorization. To further improve the previous work, this research proposes a new method based on decomposing the mixture into a series of oscillatory components termed as the intrinsic mode functions (IMF). It is shown that IMFs have several desirable properties unique to SCBSS problem and how these properties can be advantaged to relax the constraints posed by the problem. In addition, this research develops a novel method for feature extraction using psycho-acoustic model. The monaural mixed signal is transformed to a cochleagram using the gammatone filterbank, whose bandwidths increase incrementally as the center frequency increases; thus resulting to non-uniform time-frequency (TF) resolution in the analysis of audio signal. Within this domain, a family of Itakura-Saito (IS) divergence based novel two-dimensional matrix factorization has been developed. The proposed matrix factorizations have the property of scale invariant which enables lower energy components in the cochleagram to be treated with equal importance as the high energy ones. Results show that all the developed algorithms presented in this thesis have outperformed conventional methods.

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Darsono, Abd Majid. "Statistical single channel source separation." Thesis, University of Newcastle upon Tyne, 2012. http://hdl.handle.net/10443/2182.

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Single channel source separation (SCSS) principally is one of the challenging fields in signal processing and has various significant applications. Unlike conventional SCSS methods which were based on linear instantaneous model, this research sets out to investigate the separation of single channel in two types of mixture which is nonlinear instantaneous mixture and linear convolutive mixture. For the nonlinear SCSS in instantaneous mixture, this research proposes a novel solution based on a two-stage process that consists of a Gaussianization transform which efficiently compensates for the nonlinear distortion follow by a maximum likelihood estimator to perform source separation. For linear SCSS in convolutive mixture, this research proposes new methods based on nonnegative matrix factorization which decomposes a mixture into two-dimensional convolution factor matrices that represent the spectral basis and temporal code. The proposed factorization considers the convolutive mixing in the decomposition by introducing frequency constrained parameters in the model. The method aims to separate the mixture into its constituent spectral-temporal source components while alleviating the effect of convolutive mixing. In addition, family of Itakura-Saito divergence has been developed as a cost function which brings the beneficial property of scale-invariant. Two new statistical techniques are proposed, namely, Expectation-Maximisation (EM) based algorithm framework which maximizes the log-likelihood of a mixed signals, and the maximum a posteriori approach which maximises the joint probability of a mixed signal using multiplicative update rules. To further improve this research work, a novel method that incorporates adaptive sparseness into the solution has been proposed to resolve the ambiguity and hence, improve the algorithm performance. The theoretical foundation of the proposed solutions has been rigorously developed and discussed in details. Results have concretely shown the effectiveness of all the proposed algorithms presented in this thesis in separating the mixed signals in single channel and have outperformed others available methods.

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Pekdur, Ömer Keçeci Emin Faruk. "Autonomous Solid Waste Separation System Design/." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezlerengelli/master/makinamuh/T000522.pdf.

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Tang, Yan-yi, and 鄧欣宜. "Enhancing waste reduction in Hong Kong : a review on waste separation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207625.

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Waste management is always a headache to the policy makers to tackle with nowadays as we are generating more waste than the past generations. Landfill is the only disposal method in Hong Kong since the early of the 1990s and the three strategic landfills are going to be filled. Therefore, the quantity-based waste charging is going to be implemented in the near future in order to reduce waste generation. A complementary recycling system is a must to complete the newly proposed waste management policy to reduce waste volume. There are some obvious problems existing in the current recycling efforts, which hinder the success of waste separation for recycling so as to reduce waste generation. As a result, it is important to review the current Programme on Source Separation of Domestic Waste. Moreover, a successful waste separation programme for waste reduction requires fulfilling the criteria in the aspects of Recycling Facilities/Services, Public Education & Promotion and Statutory Requirement & Complementary Policy. Based on the survey results, 40% of the current recycling facilities are inconvenient or inconvenient at all and most of the respondents think that there are insufficient recycling facilities in the territory. Nearly 70% of them agree or fully agree to implement mandatory waste separation and more than a half of them prefer to fine each non-compliance below $500. Moreover, the majority of the respondents suggest that the incentives for them to recycle are not enough or not enough at all, which take up 55% of the total. And 60% of them agree or fully agree to reward people who recycle. From the site visit, it is obvious that the public abuses the roadside 3-coloured bins especially in the Hong Kong Island and the New Territories. Meanwhile, the misuse of the recycling bins leads to the cleanness problem. The tendered contractors are not doing well in terms of emptying and locking the 3-coloured bins. There are fewer problems arising from the recycling facilities or bins collecting other recyclables as these recycling bins are designed for collecting specific types of recyclables and they are not adjacent to the rubbish bins. Also, the centers for collecting bulky recyclables have management staff to collect the recyclables. According to the reply from the Environmental Protection Department, there are many monitoring works to ensure the services quality provided by the service contractors. However, it is questionable that it can maintain the performance of the contractors. Since there are increasing complaints on the unsatisfactory performance of the service contractors. As a result, the Government should review the current Programme on Source Separation of Domestic Waste in accordance with recommendations proposed in the scopes of Physical Enhancement to Recycling Facilities/Services, Education and Promotion and Policy Recommendations, including increasing the convenience and availability of the recycling facilities and the range of separation; implementing compulsory environmental education and improving the promotion on waste separation; implementing complementary policy and regulations for waste separation, monitoring the performance of waste separation and providing incentives to encourage recycling.
published_or_final_version
Environmental Management
Master
Master of Science in Environmental Management

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Klajman, Maurice. "Mixed statistics in blind source separation." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406683.

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Smaragdis, Paris J. "Information theoretic approaches to source separation." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/62337.

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Zhang, Zhenbin. "Source separation in underwater acoustic problems." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/400600/.

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When conducting passive acoustic monitoring of humpback whale songs in St Marie channel, Madagascar, sometimes recordings containing multiple singers were obtained. In this case, separating the mixtures and obtaining a recording of an individual singer is of interest. The specific method that we utilized for source separation is adapted from the proposal by Sawada et al. This algorithm can effectively operate in conditions with strong reverberation. It can also potentially cope with underdetermined mixtures where source number exceeds hydrophone number. The effectiveness of the Sawada method is verified through separation of artificial humpback song mixtures generated by the impulse responses of underwater channel model. However, this method is unreliable for the separation of real humpback whale songs as a consequence of severe background noise. We propose a noise reduction method based on weighted median threshold scheme, which significantly improves source separation performance of real recording in severe noise environments. As to the Sawada algorithm, the number of sources need to be known in order to conduct source separation. However, in reality, the number of source is unknown, Hence, we need to estimate it before performing sources separation. Various methods for automatically estimating the number of sources are investigated in this thesis, and the units counting method turns out to be the most promising one.

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Khor, Li Chin. "Blind source separation under model misfits." Thesis, University of Newcastle upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490154.

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Blind Signal Separation (BSS) is a statistical signal processing-based technique and has recently been developed for many potential applications. This thesis aims to investigate model misfits in BSS problems as well as identify and develop efficient solutions for enhancing the performance of signal separation. This research sets out to investigate model misfits associated with finite signal sample size, mixing model, source signal and noise models. The effects of finite signal sample size on several well-known cost functions have been studied and this thesis has identified the most optimal cost function in separating signals with and without the presence of noise. A set of statistical tests is further developed to measure the performance in terms of speed, accuracy and convergence of the tested BSS algorithms. This work further explores the limitations of conventional assumptions of the noiseless and square mixing model which are often violated in practice and result in poor performance in signal separation. The separation of underdetermined mixing models as well as the assumptions of the source signals and noise are also addressed. This thesis presents the development of a Bayesian framework for underdetermined mixtures that produce accurate results in the estimation of mixing matrix and signals corrupted by noise. The proposed algorithm for underdetermined mixtures is capable of modelling a wide variety of signals ranging from unimodal to multimodal and symmetric to nonsymmetric signals. An integrated noise reduction procedure provides robustness against Gaussian noise and the commonly neglected non-Gaussian noise. Results justify the customisation of an algorithm for underdetermined mixtures and demonstrate the efficacy of the proposed algorithm which is three to five times better than existing algorithms. Finally, the work investigates another model misfit in the form of nonlinearly mixed signals and the difficulty of the problem. An algorithm that accurately separates nonlinear mixtures in the presence of noise is proposed. This algorithm features a system that maintains efficient convergence rate while minimising the risk of divergence regardless of the initialised parameters. There is also a mechanism that ameliorates global convergence. Results show that the proposed algorithm outperforms existing algorithms by at least three times with its features that simultaneously address the two crucial issues in the blind separation of nonlinear mixtures.

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Smith, Paul Carson. "Broadband analog opto-electronic blind source separation." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/dissertations/fullcit/3178354.

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Mitianoudis, Nikolaos. "Audio source separation using independent component analysis." Thesis, Queen Mary, University of London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406171.

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Nesbit, Andrew Luke. "Audio Source Separation by Time-frequency Masking." Thesis, Queen Mary, University of London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504557.

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Audio source separation is a particularly interesting problem when the number of mixture channels is less than the number of sources. Our motivation for studying this is that recorded stereo music signals can often be approximated by the two-channel case. Such mixtures often have a high degree of overlapping partial frequencies and are especially challenging for standard techniques. oWe attempt to solve the problem by time-frequency masking methods, using transforms which give sparse signal representations. Our first contribution is to compare binary time-frequency masking using fixed-basis transforms, such as the short-time Fourier transform, with a new, computationally efficient method using adaptive lapped orthogonal transforms to maximise the energy of the estimated source coefficients. This assumes prior knowledge of the mixing structure (the semi-blind case). Experiments demonstrate that adaptive transforms may sometimes give better performance than fixed-basis transforms. Secondly, we describe how adaptive windowing can cause distortions in the estimated sources due to the masking process. Minimising these distortions is a trade-off between minimising blocking artifacts and minimising timedomain aliasing errors. Experiments indicate that excessive blocking artifacts decrease performance more than time-domain aliasing effects do. We propose various modifications to the transforms and mask estimation techniques to reduce these distortions. Thirdly, we describe statistically motivated extensions to binary masking techmques whIch allow more than one soUrce to tJe dCtLVe at allY tlIBEfrequency index. We also develop oracle estimators to determine empirical upper performance bounds, assuming that we have reference sources available. Oracle experiments indicate that excellent potential performance is possible compared to semi-blind methods, particularly for adaptive transforms or when more than one active source coefficient is allowed to be active. Finally, we conclude by outlining future research directions for (semi-)blind methods to approach the potential performance gains indicated by the oracle methods and to increase the applicability of our methods.

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Han, Yushen. "Score-informed musical source separation and reconstruction." Thesis, Indiana University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3609061.

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A systematic approach to retrieve individual parts in a monaural music recording with its score is introduced. We are interested in isolating the accompaniment part by removing the solo part from a recording of concerto music in which a solo instrument is accompanied by an orchestra. We require the music audio, the score, and optionally a sample library of individual notes played in isolation. Our approach is based on explicit knowledge of the musical audio at the semantic level (notes or chords) from an audio-score alignment. Such knowledge allows the spectrogram energy to be decomposed into note-based models that could be trained with the sample library. Our approach can be divided into: (1) "masking" to estimate a solo mask to remove the solo and (2) "reconstruction" to impute the missing harmonics of the orchestra notes that have been inevitably damaged in masking.

In "masking," we estimate a 2-dimensional binary mask to classify each time-frequency cell of the short-time Fourier Transform (STFT) spectrogram as either solo or accompaniment in STFT domain. We mainly employ an Expectation Maximization (EM) algorithm to decompose spectrogram magnitude into note-based models. In this process of "erasing" the soloist’s contribution to the mixture by applying the mask, the remaining orchestra is degraded. In "reconstruction," we propose a novel technique to repair such degradation. We use a state-space model for each note partial which is represented by a slowing-changing amplitude envelope and an "unwrapped" phase sequence. Such amplitude-phase representation can be computed by Kalman smoothing. It allows us to "transpose" intact partials of the orchestra part onto the degraded time-frequency region. Objective metrics and subjective listening are used on real and synthesized musical audio data for evaluation and parameter optimization.

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Badran, Salah Al-Din Ibrahim. "Efficient multiband algorithms for blind source separation." Thesis, De Montfort University, 2016. http://hdl.handle.net/2086/16089.

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The problem of blind separation refers to recovering original signals, called source signals, from the mixed signals, called observation signals, in a reverberant environment. The mixture is a function of a sequence of original speech signals mixed in a reverberant room. The objective is to separate mixed signals to obtain the original signals without degradation and without prior information of the features of the sources. The strategy used to achieve this objective is to use multiple bands that work at a lower rate, have less computational cost and a quicker convergence than the conventional scheme. Our motivation is the competitive results of unequal-passbands scheme applications, in terms of the convergence speed. The objective of this research is to improve unequal-passbands schemes by improving the speed of convergence and reducing the computational cost. The first proposed work is a novel maximally decimated unequal-passbands scheme. This scheme uses multiple bands that make it work at a reduced sampling rate, and low computational cost. An adaptation approach is derived with an adaptation step that improved the convergence speed. The performance of the proposed scheme was measured in different ways. First, the mean square errors of various bands are measured and the results are compared to a maximally decimated equal-passbands scheme, which is currently the best performing method. The results show that the proposed scheme has a faster convergence rate than the maximally decimated equal-passbands scheme. Second, when the scheme is tested for white and coloured inputs using a low number of bands, it does not yield good results; but when the number of bands is increased, the speed of convergence is enhanced. Third, the scheme is tested for quick changes. It is shown that the performance of the proposed scheme is similar to that of the equal-passbands scheme. Fourth, the scheme is also tested in a stationary state. The experimental results confirm the theoretical work. For more challenging scenarios, an unequal-passbands scheme with over-sampled decimation is proposed; the greater number of bands, the more efficient the separation. The results are compared to the currently best performing method. Second, an experimental comparison is made between the proposed multiband scheme and the conventional scheme. The results show that the convergence speed and the signal-to-interference ratio of the proposed scheme are higher than that of the conventional scheme, and the computation cost is lower than that of the conventional scheme.

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Homa, Laura A. "Bayesian Methods for Source Separation in Magnetoencephalography." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1365175207.

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Zhou, Lihong. "Blind source separation systems for hearing aids." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28395.

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For many real-life situations, there is more than one speaker at a given time and people need to concentrate on a target sound signal to extract it. This process happens naturally for people with a normal hearing ability, but it is very difficult for hearing impaired persons. In this thesis, we present a system for enhancing the quality of the signal produced by a hearing aid. The proposed system combines spatial information with blind source separation (BSS) to extract the target signal. Results show that the proposed system can locate a target signal in different environments, with a good learning ability. The problem of locating and extracting a target source signal is first investigated. By applying a time-frequency masking method, it is then shown that the performance can be improved. Finally, the problem of underdetermined BSS is investigated and solved by combining a MVDR beamformer with a determined BSS system.

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Tang, Hoi-wan, and 鄧凱雲. "The waste separation and recycling scheme in schools." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31255103.

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Tang, Hoi-wan. "The waste separation and recycling scheme in schools /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23425118.

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Daga, Anil Kumar Namuduri Kameswara. "Source channel separation in energy constrained multiterminal source-channel communications schemes subtitle /." Diss., A link to full text of this thesis in SOAR, 2006. http://soar.wichita.edu/dspace/handle/10057/621.

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Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering.
"December 2006." Title from PDF title page (viewed on Oct. 29, 2007). Thesis adviser: Kamesh Namuduri. Includes bibliographic references (leaves 28-30).

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Lefèvre, Augustin. "Dictionary learning methods for single-channel source separation." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2012. http://tel.archives-ouvertes.fr/tel-00797093.

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In this thesis we provide three main contributions to blind source separation methods based on NMF. Our first contribution is a group-sparsity inducing penalty specifically tailored for Itakura-Saito NMF. In many music tracks, there are whole intervals where only one source is active at the same time. The group-sparsity penalty we propose allows to blindly indentify these intervals and learn source specific dictionaries. As a consequence, those learned dictionaries can be used to do source separation in other parts of the track were several sources are active. These two tasks of identification and separation are performed simultaneously in one run of group-sparsity Itakura-Saito NMF. Our second contribution is an online algorithm for Itakura-Saito NMF that allows to learn dictionaries on very large audio tracks. Indeed, the memory complexity of a batch implementation NMF grows linearly with the length of the recordings and becomes prohibitive for signals longer than an hour. In contrast, our online algorithm is able to learn NMF on arbitrarily long signals with limited memory usage. Our third contribution deals user informed NMF. In short mixed signals, blind learning becomes very hard and sparsity do not retrieve interpretable dictionaries. Our contribution is very similar in spirit to inpainting. It relies on the empirical fact that, when observing the spectrogram of a mixture signal, an overwhelming proportion of it consists in regions where only one source is active. We describe an extension of NMF to take into account time-frequency localized information on the absence/presence of each source. We also investigate inferring this information with tools from machine learning.

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Anemüller, Jörn. "Across-frequency processing in convolutive blind source separation." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962819247.

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Liu, Xianhua Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Blind source separation methods and their mechanical applications." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/24961.

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Blind Source Separation is a modern signal processing technique which recovers both the unknown sources and unknown mixing systems from only measured mixtures of signals. It has application in diverse fields such as communication, image processing, geological exploration and biomedical signal processing etc. This project studies the BSS problem, develop separation methods and reveal the potential for mechanical engineering applications. There are two models for blind source separation corresponding to the two ways that the sources are mixed, the instantaneous mixing model and the convolved mixing model. The author carried out a theoretical study of the first model by proposing an idea called Redundant Data Elimination which leads to geometric interpretation of the model, explains that circular distribution property is the reason why Gaussian signal mixtures can not be separated, and showed that this idea can improve separation accuracy for unsymmetrically distributed sources. This new idea enabled evaluation and comparison of two well-known algorithms and proposal of a simplified algorithm based on Joint Approximate Diagonalization of fourth order cumulant matrices, which is further developed by determining an optimized parameter value for separation convergence. Also based on the understanding from the RDE, an outlier spherical projection method is proposed to improve separation accuracy against outlier errors. Mechanical vibration or acoustic problems belong to the second model. After some theoretical study of the problem and the model, a novel application of the Blind Least Mean Square algorithm using Gray's variable norm as cost function is applied to engine vibration data to separate piston slap, fuel injection noise and cylinder pressure effects. Further, the algorithm is combined with a deflation algorithm for successive subtraction of recovered source responses from the measured mixture to enable the recovery of more sources. The algorithms are verified to be successful by simulation, and the separated engine sources are proved reasonable by analysing the engine operation and physical properties of the sources. The author also studied the relationship between these two models, the problems of different approaches for solving the model such as the frequency domain approach and the Bussgang approach, and sets out future research interests.

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Sansrimahachai, Puttachad. "Blind source separation algorithms for MIMO communication systems." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419916.

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Addison, W. D. "Blind source separation using spatial and temporal priors." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525254.

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Hao, Jiucang. "Speech enhancement and source separation using probabilistic models." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3330360.

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Thesis (Ph. D.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed Nov. 19, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 113-117).

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Che, Viet Nhat Anh. "Cyclostationary analysis : cycle frequency estimation and source separation." Thesis, Saint-Etienne, 2011. http://www.theses.fr/2011STET4035.

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Le problème de séparation aveugle de sources a but de retrouver un ensemble des sources signaux statistiquement indépendants à partir seulement d’un ensemble des observations du capteur. Ces observations peuvent être modélisées comme un mélanges linéaires instantané ou convolutifs de sources. Dans cette thèse, les sources signaux sont supposées être cyclostationnaire où leurs fréquences cycles peuvent être connues ou inconnu par avance. Premièrement, nous avons établi des relations entre le spectre, spectre de puissance d’un signal source et leurs composants, puis nous avons proposé deux nouveaux algorithmes pour estimer sa fréquences cycliques. Ensuite, pour la séparation aveugle de sources en mélanges instantanés, nous présentons quatre algorithmes basés sur diagonalisation conjoint approchées orthogonale (ou non-orthogonales) d’une famille des matrices cycliques multiples moment temporel, or l’approche matricielle crayon pour extraire les sources signaux. Nous introduisons aussi et prouver une nouvelle condition identifiabilité pour montrer quel type de sources cyclostationnaires d’entrée peuvent être séparées basées sur des statistiques cyclostationnarité à l’ordre deux. Pour la séparation aveugle de sources en mélanges convolutifs, nous présentons un algorithme en deux étapes basées sur une approche dans le domaine temporel pour récupérer les signaux source. Les simulations numériques sont utilisés dans cette thèse pour démontrer l’efficacité de nos approches proposées, et de comparer les performances avec leurs méthodes précédentes
Blind source separation problem aims to recover a set of statistically independent source signals from a set of sensor observations. These observations can be modeled as an instantaneous or convolutive mixture of the same sources. In this dissertation, the source signals are assumed to be cyclostationary where their cycle frequencies may be known or unknown a priori. First, we establish relations between the spectrum, power spectrum of a source signal and its component, then we propose two novel algorithms to estimate its cycle frequencies. Next, for blind separation of instantaneous mixtures of sources, we present four algorithms based on orthogonal (or non-orthogonal) approximate diagonalization of the multiple cyclic temporal moment matrices, and the matrix pencil approach to extract the source signal. We also introduce and prove a new identifiability condition to show which kind of input cyclostationary sources can be separated based on second-order cyclostationarity statistics. For blind separation of convolutive mixtures of sources signal or blind deconvolution of FIR MIMO systems, we present a two-steps algorithm based on time domain approach for recovering the source signals. Numerical simulations are used throughout this thesis to demonstrate the effectiveness of our proposed approaches, and compare theirs performances with previous methods

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Parathai, Phetcharat. "Blind source separation using statistical nonnegative matrix factorization." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2830.

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Blind Source Separation (BSS) attempts to automatically extract and track a signal of interest in real world scenarios with other signals present. BSS addresses the problem of recovering the original signals from an observed mixture without relying on training knowledge. This research studied three novel approaches for solving the BSS problem based on the extensions of non-negative matrix factorization model and the sparsity regularization methods. 1) A framework of amalgamating pruning and Bayesian regularized cluster nonnegative tensor factorization with Itakura-Saito divergence for separating sources mixed in a stereo channel format: The sparse regularization term was adaptively tuned using a hierarchical Bayesian approach to yield the desired sparse decomposition. The modified Gaussian prior was formulated to express the correlation between different basis vectors. This algorithm automatically detected the optimal number of latent components of the individual source. 2) Factorization for single-channel BSS which decomposes an information-bearing matrix into complex of factor matrices that represent the spectral dictionary and temporal codes: A variational Bayesian approach was developed for computing the sparsity parameters for optimizing the matrix factorization. This approach combined the advantages of both complex matrix factorization (CMF) and variational-sparse analysis. An imitated-stereo mixture model developed by weighting and time-shifting the original single-channel mixture where source signals can be modelled by the AR processes. The proposed mixing mixture is analogous to a stereo signal created by two microphones with one being real and another virtual. The imitated-stereo mixture employed the nonnegative tensor factorization for separating the observed mixture. The separability analysis of the imitated-stereo mixture was derived using Wiener masking. All algorithms were tested with real audio signals. Performance of source separation was assessed by measuring the distortion between original source and the estimated one according to the signal-to-distortion (SDR) ratio. The experimental results demonstrate that the proposed uninformed audio separation algorithms have surpassed among the conventional BSS methods; i.e. IS-cNTF, SNMF and CMF methods, with average SDR improvement in the ranges from 2.6dB to 6.4dB per source.

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Zhang, Jingyi. "Statistical blind source separation of post-nonlinear mixture." Thesis, University of Newcastle upon Tyne, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485858.

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Blind Source Separation (BSS) is a statistical signal processing technique and has recently been developed for many applications. The aim of this thesis is to investigate the blind signal separation problem under the environment where noise, reverberation and nonlinear distortion exist in the mixture and to develop novel solutions to solve the problem. The success and efficacy of the proposed algorithms is analysed in terms of robustness to noise, accuracy of recovered signal and speed of convergence. Linear BSS algorithms for instantaneous and convolutive mixtures are investigated and tested by a set of specially designed simulated experiments under various conditions. In addition, the post-nonlinear instantaneous mixture model has been critically researched and the theory of signal separability has been established. To overcome the limitation and drawbacks of the existing works on post-nonlinear mixture, a novel solution has been developed to separate noisy post-nonlinear instantaneous mixtures of non-stationary and temporally correlated sources and this work further extends to the case of noisy convolutive mixture. The proposed models allow source non-stationarity and temporal correlation to be incorporated into the new solutions. The Maximum Likelihood (ML) approach has been developed for both of the proposed algorithms to estimate the model parameters by the Expectation Maximisation (EM) algorithm and the post-nonlinearity is estimated by a set of self-updating polynomials whose coefficients are updated as part of the model parameters. The theoretical foundation of the proposed solutions has been rigorously developed and discussed in detail. The new algorithms have been tested by simulations using both synthetically generated and recorded speech signals to verify the accuracy and efficacy. The results show that the proposed algorithms outperform existing algorithms in the separation performance where significant improvement has been obtained.

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Abrar, Shafayat. "Blind channel equalization and instantaneous blind source separation." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540044.

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Mehta, Rupel. "The separation of waste oily water using carbon adsorption." Thesis, University of Bath, 2007. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440880.

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Song, He. "Anaerobic digestion of source-segregated domestic food waste." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/402998/.

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Anaerobic digestion (AD) is an attractive waste treatment process in which both pollution control and energy recovery can be achieved. Source-segregated domestic food waste (FW) has a high organic content on a dry weight basis and is rich in lipids and proteins, indicating the potential for a good biogas yield with high methane content. Process instability, however, has often been reported in food waste digesters, which was mainly manifested by the accumulation of volatile fatty acids (VFA) and reduction of specific methane production. Trace element (TE) supplementation has been proved to be an effective way to rectify this problem and has been applied to industrial AD plants. This practice, however, was usually characterised by a trial-and-error approach due to the lack of a clear understanding of the impact of TEs on AD under different process conditions. The aim of this study was therefore to optimise TE dosing strategies for FW digestion at different loading rates, with particular attention to the role of cobalt (Co) and selenium (Se). The limiting concentrations of Co and Se were studied in long-term continuously stirred tank reactor (CSTR)-type digester experiments at organic loading rates (OLR) from 1.8 to 5 kg volatile solids (VS) m-3 d-1. In a digester operated at OLR 1.8 kg VS m-3 d-1 without TE addition, dosing of Co at a strength of 1 mg Co kg-1 fresh matter was effective to stimulate the complete degradation of accumulated VFA. Around 2500 mg L-1 VFA built up, however, after OLR increased to 2.5 kg VS m-3 d-1; then dropped slightly by addition of Se at a strength of 0.05 mg Se kg-1 fresh matter. After stepwise increases in Se concentration to 0.2 mg kg-1, VFA reduced to less than 1000 mg L-1. In another 2 digesters, at OLR 3 and 4 kg VS m-3 d-1 respectively, TE washing-out was introduced for determination of the limiting Co concentration. All TE supplementation was ceased in these 2 digesters for around 300 days with the exception of continuous addition of 0.2 mg kg-1 of Se. VFA accumulation up to 30000 mg L-1 occurred in one digester immediately after the OLR increased from 4 to 5 kg VS m-3 d-1 and later up to 22500 mg L-1 in the other digester when OLR increased from 3 to 4 kg VS m-3 d-1. By gradually increasing Co concentration in both digesters to 0.3~0.5 mg kg-1, VFA started to be consumed. At the end of test, the recovered digester with OLR 5 kg VS m-3 d-1 was running stably with 0.2 mg kg-1 Se and 0.3~0.5 mg kg-1 Co addition, with a pH of 7.8, IA/PA ratio 0.4, specific methane production (SMP) 0.47 standard temperature and pressure (STP) m3 CH4 kg-1 VS d-1, volumetric methane production (VMP) 2.37 STP m3 CH4 m-3 d-1, and VFA concentration less than 500 mg L-1. To further understand the effect of trace elements on VFA production, short-term trials were carried out to assess their function in VFA production. The results indicated that with accumulated VFA, supplementation of trace elements stimulated VFA production to a greater extent than VFA consumption. Effect of organic loading rate on TE dosing strategy and digester performance was studied in 5 digesters, all of which had stable operation but different trace element addition histories. One pair digesters was run as control at OLR 5 kg VS m-3 d-1 over the course of the experiment, another pair operated with a gradual loading increase to 6, 7, 8 and 9 kg VS m-3 d-1. A SMP of 0.46±0.02 STP m3 CH4 kg-1 VS d-1 at OLR 8 kg VS m-3 d-1 was achieved. Volatile solids destruction (VSD) rates were similar between OLR 5 and 8 kg VS m-3 d-1, at approximately 0.74~0.75, but reduced to 0.71~0.72 at OLR 9 kg VS m-3 d-1. Residual methane production (RBP) test results showed that biogas production of digestate from OLR 5 and 7 kg VS m-3 d-1 were similar, whereas digestate from OLR 9 kg VS m-3 d-1 generated more biogas than OLR 5 kg VS m-3 d-1, indicating lower conversion efficiency was achieved at OLR 9 kg VS m-3 d-1. Nitrogen mass balance equations were developed to distinguish nitrogen distribution in digesters. These showed that microbial biomass density increased along with OLR increase, which in turn requires an increase in TE addition. The specific rate of biomass increase at OLR 9 kg VS m-3 d-1, however, was lower than at 8 kg VS m-3 d-1, reflecting the decrease in specific methane production and VSD rate. The results indicate that FW digester was able to operate at OLR 8 kg VS m-3 d-1, without loss of performance when compared with OLR 5 kg VS m-3 d-1. Loading 9 kg VS m-3 d-1 was regarded as overloaded due to the lower hydrolysis and acidification efficiency. The fifth digester, in which the same TE dosing was applied, was operated with random loading: a daily load between 2.5~7.5 kg VS m-3 d-1 was randomly introduced while weekly average OLR was maintained at 5 kg VS m-3 d-1. Stable performance was observed in this digester with 2.27 STP m3 CH4 m-3 d-1 of 30-day rolling average VMP and 76% of VSD rate, and VFA concentrations less than 500 mg L-1. Further research on essential TE supplementation for stable FW digestion at high loading was carried out. All TE additions were ceased except 0.3 mg kg-1 of Co and 0.2 mg kg-1 of Se, in two pairs of digesters at loading 5 and 8 kg VS m-3 d-1, respectively. VFA accumulation occurred in digesters at the higher loading, which finally failed. VFA fluctuated around 4000 mg L-1 in digesters at OLR 5 kg VS m-3 d-1, until the rest of trace elements in a full 11 trace elements recipe were reintroduced, when VFA degraded quickly to below 1000 mg L-1. The research provided new insight on optimising essential TE supplementation to FW digestion, especially at moderate and high loading rates, to ensure stable and high productive biogas production.

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Jordan, Alexander Thomas. "Liquid phase plasma technology for inkjet separation." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47543.

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Currently most deinking technologies are dependent upon flotation and dissolved air flotation (DAF) technology in order to separate inkjet ink from fiber and water. Much of this technology is based on ink that is extremely hydrophobic. This made flotation and DAF very easy to use because the ink in the water would very easily move with the air in flotation and be brought to the surface, after which the ink can be skimmed and the pulp can be used. Now that small scale printing has become the norm, there has been a move to high quality, small scale printing. This involves the use of a hydrophilic ink. Hydrophilic ink cannot be easily separated from water and fiber the same way the hydrophobic ink can be. With low concentrations of hydrophilic ink in the process water stream, it can be absorbed into the process but as the hydrophilic ink concentration rises alternative methods will be needed in order to separate inkjet ink from water. One solution is to find a method to effectively increase ink particle size. This will enable the ink particles to be filtered or to have an increase ecacy of removal during flotation. In this thesis, one solution is discussed about how electric field and electric plasma technologies can be used to increase particle size and help purify process water in recycle mills. This plasma treatment can very effectively bring ink particles together so that they may be separated by another method. There are two methods by which this may take place. One is polymerization and the other is electro-coagulation. These processes can work side by side to bring ink particles together. This plasma treatment process creates free radicals by stripping off hydrogen atoms from surrounding organic matter. These free radicals then react with the high alkene bond content within the ink to create a very large covalently bonded molecule. This is the new mechanism that is being investigated in this thesis. The other action that is taking place is electro-coagulation. Plasma treated ink can be filtered out using a cellulose acetate or cellulose nitrate membrane or they can be filtered using paper or fiber glass filters as well. The extent at which these can be filtered out is dependent on the size of the pores of the filter. In this study, it was shown that the plasma treatment was able to clean water with a fairly small amount of energy. It was also found that treatment time and concentration had very little eect on the outcome of the treatment ecacy. One factor that did have an effect was the pH. At very high pH values the process became noticeably less eective. The high pH essentially eliminated the electro-coagulation aspect of the treatment process and also hurt the polymerization aspect as well because of lower amount of hydrogen atoms available for the plasma to create free radicals. A model of the process was used to try to give the reader an idea of the ecacy that the process would have in an industrial scale process. The model assumes that two types of ink particles exist. One is ink that has a radical and another in which the ink does not have a radical. The model also assumes that if ink is at all polymerized, ink is filtered out with the 0.8 micron filter. The model assumes three reactions; initialization, propagation and partial termination. The partial termination is a result from the general chemical structure of ink. Ink has many double bonds in its general structure which makes termination very unlikely to occur, so the model assumes that on average when two radials interact that only one is eliminated. This model is only supposed to give the reader an idea of the ecacy of the process. The numbers provided in the model will change very significantly in a different system. The evidence behind polymerization aspect of the process comes from two main sources. One is the small molecule analysis from methanol after being exposed to the plasma and the other from the plasma being exposed to allyl alcohol. The small molecule analysis shows that the process generates free radicals on organic molecules. Methanol was exposed to the plasma and then the resulting GC/MS analysis showed that 1,2-ethanediol was present, this showed that the electric discharge process was able to create free radicals on organic molecules in the liquid phase. Using a similar process the plasma discharge process was exposed to a mixture of allyl alcohol, water and propanol and water in two separate experiments. The difference between these two molecules is an alkene bond that is between the carbon two and carbon three atoms. The particle size of both samples was then analyzed and it was shown that the solution with allyl alcohol had an average particle size about an order of magnitude larger than the solution with propanol in it. Because of all the evidence discussed here and in the rest of the thesis we believe that the plasma treatment of ink has both polymerization and electro-coagulation aspect. This process could also be a potential solution to the water soluble ink problem that will soon face the recycling industry.

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Lösch, Benedikt [Verfasser]. "Complex Blind Source Separation with Audio Applications / Benedikt Lösch." München : Verlag Dr. Hut, 2013. http://d-nb.info/1042307806/34.

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Leong, Wai Yie. "Implementing blind source separation in signal processing and telecommunications /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19158.pdf.

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Talantzis, Fotios. "Equalization and source separation techniques in acoustic reverberant environments." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428487.

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Theis, Fabian J. [Verfasser]. "Geometric Source Separation : Algorithms and Applications / Fabian J Theis." Aachen : Shaker, 2003. http://d-nb.info/1174513586/34.

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Abadi, Bahador Makki. "New tensor factorization based approaches for blind source separation." Thesis, University of Surrey, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543925.

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E, Okwelume Gozie, and Ezeude Anayo Kingsley. "BLIND SOURCE SEPARATION USING FREQUENCY DOMAIN INDEPENDENT COMPONENT ANALYSIS." Thesis, Blekinge Tekniska Högskola, Avdelningen för signalbehandling, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1312.

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Our thesis work focuses on Frequency-domain Blind Source Separation (BSS) in which the received mixed signals are converted into the frequency domain and Independent Component Analysis (ICA) is applied to instantaneous mixtures at each frequency bin. Computational complexity is also reduced by using this method. We also investigate the famous problem associated with Frequency-Domain Blind Source Separation using ICA referred to as the Permutation and Scaling ambiguities, using methods proposed by some researchers. This is our main target in this project; to solve the permutation and scaling ambiguities in real time applications
Gozie: modebelu2001@yahoo.com Anayo: ezeudea@yahoo.com

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Alphey, Marcus J. T. "Blind source separation : the effects of signal non-stationarity." Thesis, University of Edinburgh, 2002. http://hdl.handle.net/1842/11220.

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This thesis investigates the effect of non-stationarity reduction, in the form of silence removal, on the performance of blind separation and deconvolution techniques for speech signals. An information-maximisation-based system is used for the separation of instantaneously mixed signals, and a decorrelating system for convolutively mixed signals. An introduction to the concepts of adaptive signal processing, blind signal processing and artificial neural networks is presented. A review of approaches to solving the blind signal separation and deconvolution problems is provided. The susceptibility of the information-maximisation approach to signal non-stationarity is discussed and two methods of silence identification and removal are compared and used to pre-process data before blind separation. The "infomax" approach is used to separate instantaneous mixtures, and is also modified to incorporate silence assessment and removal techniques to form an on-line system. Further modifications are made to the algorithm to investigate the effect of alternative update strategies, and these are compared with experimental results from identical modifications to diverse separating algorithms. A performance metric is used to assess the quality of separation achieved. The application of these techniques to convolutively mixed speech signals is also investigated, using the CoB1iSS algorithm. The effectiveness of the application of the silence removal techniques to both the time domain and frequency domain representations of the outputs is tested. While this form of non-stationarity reduction improves the rate of convergence for instantaneous mixtures, it does not cause any significant improvement in separation performance under most of the experimental conditions tested. No significant difference in performance was noted for the separation of convolutive mixtures in either the time or frequency domain.

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Latif, Mohamed Amin. "Localization of brain signal sources using blind source separation." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/54567/.

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Reliable localization of brain signal sources by using convenient, easy, and hazardless data acquisition techniques can potentially play a key role in the understanding, analysis, and tracking of brain activities for determination of physiological, pathological, and functional abnormalities. The sources can be due to normal brain activities, mental disorders, stimulation of the brain, or movement related tasks. The focus of this thesis is therefore the development of novel source localization techniques based upon EEG measurements. Independent component analysis is used in blind separation (BSS) of the EEG sources to yield three different approaches for source localization. In the first method the sources are localized over the scalp pattern using BSS in various subbands, and by investigating the number of components which are likely to be the true sources. In the second method, the sources are separated and their corresponding topographical information is used within a least-squares algorithm to localize the sources within the brain region. The locations of the known sources, such as some normal brain rhythms, are also utilized to help in determining the unknown sources. The final approach is an effective BSS algorithm partially constrained by information related to the known sources. In addition, some investigation have been undertaken to incorporate non-homogeneity of the head layers in terms of the changes in electrical and magnetic characteristics and also with respect to the noise level within the processing methods. Experimental studies with real and synthetic data sets are undertaken using MATLAB and the efficacy of each method discussed.

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Guddeti, Ram Mohana Reddy. "Perceptually motivated blind source separation of convolutive audio mixtures." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/12073.

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The first objective of this thesis is to apply psycho-acoustic principles to the spatial processing of speech signals in noisy and reverberant environment. The key assumption that will be adopted is that modern signal processing has failed to mimic the cock-tail party effect because there has been no attempt to adequately incorporate the psycho acoustical phenomenon of audio masking to aid source separation. A quasi linear mechanism for mimicking simultaneous frequency masking and temporal masking (post masking) techniques are developed. This frame work is used to construct blind source separation algorithms that exploit audio masking prior to source separation (preprocessor) and after source separation (postprocessor). The final objective of this thesis is to exploit the perceptual irrelevancy of some of the input speech spectrum using the perceptual masking techniques before utilizing the subspace method as a preprocessor of the frequency-domain ICA (FDICA) which reduces the effect of room reflections in advance and the remaining direct sounds then being separated by ICA. Incorporating the perceptual masking techniques prior to the application of FDICA with the subspace method as preprocessor not only reduces the computational complexity of similarity measure for solving the permutations but also avoids the so-called permutation problem by targeting a specific speech signal more intelligible than the available microphone signals.

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Herrmann, Frank. "Independent component analysis with applications to blind source separation." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399147.

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Woo, Grace R. "Demonstration and evaluation of co-channel DBPSK source separation." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42170.

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Abstract:

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2007.
Includes bibliographical references (leaves 51-53).
This thesis presents a Differential Binary Phase Shift Key (DBPSK) source separation system implemented with the GNU Software Defined Radio (SDR) platform and interfaced with the existing MIT community Radio Frequency Identification (RFID) system. Source separation, well studied in the theoretical signal processing setting, presents an opportunity to achieve higher throughput in a practical SDR deployment. While much research has centered around the design of complex multi-input-multi-output (MIMO) and code division multiple access (CDMA) systems, single antenna source separation presents a simple alternative that is suitable in settings such as RFID where sources are naturally synchronized. Motivated by the analysis of physical channel properties with GNU SDR, this thesis documents the complete design process from the physical layer to the application layer and presents a realization of a co-channel DBPSK source separating technique. The result is an intelligent RFID source-separating reader that is capable of decoding multiple "dumb" cards.
by Grace R. Woo.
S.M.

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