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Hedjam, Rachid. "Visual image processing in various representation spaces for documentary preservation." Mémoire, École de technologie supérieure, 2013. http://espace.etsmtl.ca/1186/1/HEDJAM_Rachid.pdf.
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Cette thèse établit un cadre de travail de traitement d’images pour le rehaussement et la restauration des images de documents historiques (IDH) dans deux espaces de représentations différents : l’espace des niveaux de gris et de couleur et l’espace multispectral (MS). Elle consiste en trois contributions majeures: 1) la binarisation d’IDH en niveaux de gris ou en couleur, 2) la restauration des IDH capturées au moyen de l’imagerie MS, et 3) l’estimation de données de référence (DR) utilisées à des fins d’évaluation des algorithmes de binarisation d’IDH. La binarisation d’IDH est l’une des techniques de rehaussement qui produit des informations binaires faciles à manipuler par des méthodes d’analyse de haut niveau (OCR, par exemple), et moins coûteuse en termes de calcul par rapport aux images couleurs ou en niveaux de gris. La restauration des IDH dans un espace de représentation MS améliore leur lisibilité, ce qui n’est pas possible avec les méthodes classiques de restauration basées sur l’intensité ou la couleur. La lisibilité des IDH est la principale préoccupation des historiens et bibliothécaires qui souhaitent toujours transférer les connaissances et faire revivre l’ancien patrimoine culturel et scientifique. L’utilisation des systèmes d’imagerie MS est une piste de recherche à la fois nouvelle et attrayante dans le domaine du traitement numérique d’IDH. Dans cette thèse, ces systèmes sont également utilisés pour estimer automatiquement des DR plus précises à utiliser pour l’évaluation d’algorithmes de binarisation d’IDH afin de poursuivre le niveau de performance humaine.
Notre première contribution est une nouvelle méthode de binarisation adaptative destinée aux IDH en niveaux de gris et couleurs. Puisque la dégradation est présente un peu partout sur la surface des IDH, les méthodes de binarisation doivent être adaptées pour gérer localement ces phénomènes de dégradation. Malheureusement, ces méthodes ne sont pas efficaces, car elles ne sont pas en mesure de capturer les traits de texte de faible intensité, ce qui entraîne une détérioration de la performance des moteurs de reconnaissance de caractères (OCR). L’approche proposée détecte en premier lieu un sous-ensemble de pixels de texte les plus probables, qui sont utilisés pour estimer les paramètres locaux des deux classes (texte et fond), puis effectue une classification à base de maximum de vraisemblance (MV) afin de classifier localement les pixels restants en fonction de leur appartenance aux classes. Au meilleur de notre connaissance, c’est la première fois que l’estimation des paramètres et la classification locale dans un cadre de MV a été introduite pour la binarisation d’IDH avec des résultats prometteurs. Une limitation de cette méthode, comme pour toutes les méthodes de ehaussement basées sur l’intensité, est qu’elles ne sont pas efficaces dans le traitement d’IDH gravement dégradées. Développer des méthodes plus avancées fondées sur les informations MS serait une alternative prometteuse de la recherche.
Dans la deuxième contribution, une nouvelle approche pour la restauration visuelle d’IDH est définie. L’approche vise à fournir une meilleure qualité visuelle des IDH à l’utilisateur final (historien, bibliothécaire, etc.). Plus précisément, elle vise à les restaurer à partir des dégradations, tout en conservant intact leur aspect original. En pratique, ce problème ne peut pas être résolu facilement par les méthodes classiques de restauration basées sur l’intensité. Pour faire face à ces limitations, l’imagerie MS est utilisée pour produire d’autres images spectrales dans la lumière invisible (infrarouge et ultraviolet), ce qui donne un meilleur contraste au contenu des IDH. Le cadre de travail variationnel de ’inpainting’ proposé ici pour la restauration d’IDH consiste à isoler les dégradations dans les images spectrales infrarouges, puis les retoucher (’inpainting’) dans les images spectrales visibles. L’image couleur finale à visualiser est donc reconstruite à partir des images spectrales visibles restaurées. Au meilleur de notre connaissance, c’est la première fois que la technique de ’inpainting’ a été mise en place pour la restauration d’IDH ultispectrales. Les résultats expérimentaux sont prometteurs, et notre objectif, en collaboration avec la BAnQ (Bibliothèque et Archives nationales du Québec), est de rendre disponible les documents du patrimoine dans le domaine public et de construire un moteur intelligent pour y accéder. Il est utile de noter que le modèle proposé peut être étendu à d’autres applications basées sur les images MS.
Notre troisième contribution, qui consiste à considérer un nouveau problème d’estimation de DR, est présentée afin de montrer l’importance de travailler avec des images MS plutôt que des images en niveaux de gris ou en couleur. Les DR sont nécessaires pour comparer différents algorithmes de binarisation, et ils sont habituellement générés par un expert. Cependant, les DR d’un expert sont toujours sujettes à des erreurs d’étiquetage et de jugement, en particulier dans le cas des données dégradées traitées dans des espaces de représentation restreints (images en niveaux de gris ou couleur). Dans la méthode proposée, plusieurs RD générées par plusieurs experts sont utilisées en combinaison avec l’image de document MS pour estimer une nouvelle RD plus précise. L’idée est d’inclure la fidélité de données multivariée et le degré de consensus des experts à propos des étiquettes dans un cadre unique de classification Bayésien pour estimer la probabilité a posteriori des nouvelles étiquettes formant la RD finale à estimer. Nos expériences montrent que les RD estimées sont plus précises que celles générées individuellement par l’expert. Au meilleur de notre connaissance, aucun travail similaire, combinant les RD générées par un expert et les données MS, a été effectuée pour l’estimation des RD.
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Sturt, Patrick. "Syntactic re-analysis in human language processing." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/517.
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This thesis combines theoretical, computational and experimental techniques in the study of reanalysis in human sentence comprehension. We begin by surveying the main claims of existing theories of reanalysis, and identify representation preservation as a key concept. We show that the models which most obviously feature representation preservation are those which have been formulated with in the monotonicity framework, which assumes that there are aspects of representation which are updated monotonically (i.e.non-destructively) from state to state, and that any reanalysis which requires a non-monotonic update is predicted to cause processing disruption. Next, we present a computational implementation, based on the monotonic theory of Gorrell (1995b). We argue that in constructing such a model of reanalysis, it is essential to consider not only declarative constraints, but also the computational processes through which reanalysis routines explicit, leading to novel predictions in cases where there exist more than one alternative for structural revision. I show why preferences for such reanalysis ambiguities may differ between predominantly head initial languages such as English, and head final languages such as Japanese. After this, we consider the empirical consequences of the implemented model, in particular in relation to recent experimental data concerning modifier attachment. We shoe that the model is too restrictive, and we argue that the appropriate way to expand its coverage is to apply the monotonicity constraints not directly to phrase structure, but to thematics structure. We provide a general framework which allows such non-phrase structural models to be defined, maintaining the same notion of monotonicity that was employed in the previous model. We go on to provide solutions to some computational problems which accompany this change. Finally, we present two experimental studies. The first of these considers the issue of reanalysis ambiguity, and specifically the existence of a recency preference is confirmed in off-line tasks, such as comprehension accuracy and a questionnaire experiment, but is not confirmed in self-paced reading. We discuss some possible reasons for this dissociation between the on-line and off-line results. The second experimental study considers the effect of modifier attachment in Japanese relative clause ambiguities. In this study, we confirm the influence of thematic structure on the resolution of Japanese relative clause ambiguities, and we argue that this effect should be interpreted in terms of a constraint on reanalysis.
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Lyver, André. "Formulation, shelf-life and safety studies on value-added seafood products." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/MQ29749.pdf.
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Hiremath, Nikhil Davangere. "Studies on high pressure processing and preservation of mango juice : pressure destruction kinetics, process verification and quality changes during storage." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82251.
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Thermal processing is the primary mode of preservation of mango products, which can be considerably damaging to the delicate quality of mango. HP processing could thus be a potential alternative for extending the shelf-life of mango products. Establishing HP processing technology need data on microbial inactivation kinetics and shelf-life study of the product. The objective of this research was therefore to evaluate the application of HP treatment for inactivation of microorganisms (pathogenic and spoilage type) and to evaluate the shelf-life of HP treated mango juice.HP destruction kinetics of three common spoilage microorganisms, Leuconostoc mesenteroides, Zygosaccharomyces bailii and Pichia membranaefaciens and two pathogenic microorganisms, Escherichia coli O157:H7 and Listeria monocytogenes Scott A, were evaluated at 250-550 MPa with 0-60 min holding time at room temperature with species specific initial counts between 10 6 to 108 CFU/mL.
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Carstens, Andries Theunis. "Digitising photographic negatives and prints for preservation." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/1355.
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A DISSERTATION PRESENTED TO THE FACULTY OF INFORMATICS AND DESIGN
OF THE CAPE PENINSULA UNIVERSITY OF TECHNOLOGY IN FULFILMENT OF
THE REQUIREMENTS FOR THE DEGREE OF MAGISTER TECHNOLOGIAE
PHOTOGRAPHY
CAPE PENINSULA UNIVERSITY OF TECHNOLOGY
2013This study deals with the pitfalls and standards associated with the digitisation of photographic artefacts in formal collections. The popularity of the digital medium caused a rapid increase in the demand for converting images into digital files. The need for equipment capable of executing the task successfully, the pressure on collection managers to display their collections to the world and the demand for knowledge needed by managers and operators created pressure to perform optimally and often in great haste. As a result of the rush to create digital image files to be displayed and to be preserved, the decisions that are being made may be questionable. The best choice of file formats for longevity, setting and maintaining standards to guarantee quality digital files and consultation with experts in the field of digitisation as well as attention to best practices are important aspects which must be considered. In order to determine the state of affairs in countries with an advanced knowledge and experience in the field of digitisation, a comprehensive literature study was done. It was found that enough information exists to enable collection managers in South Africa to make well informed decisions to ensure a high quality of digital collection. By means of questionnaires, a survey was undertaken amongst selected Western Cape image preservation institutions to determine the level of knowledge of the managers who are required to make informed decisions. The questionnaire was designed to give insight into choices being made regarding the technical quality, workflow and best practice aspects of digitisation. Comparing the outcome of the questionnaires with best practices and recommended standards in countries with an advanced level of experience it was found that not enough of this experience and knowledge is used by local collection managers although readily available. In some cases standards are disregarded completely. The study also investigated by means of questionnaires the perception of the digital preservation of image files by fulltime photographic students and volunteer members of the Photographic Society of South Africa. It was found that uncertainty exist within both groups with regard to file longevity and access to files in five to ten year's time. Digitisation standards are set and maintained by the use of specially designed targets which enable digitising managers to maintain control over the quality of the digital content as well as monitoring of equipment performance. The use of these targets to set standards were investigated and found to be an accurate and easy method of maintaining control over the standard and quality of digital files. Suppliers of digitising equipment very often market their equipment as being of a high quality and being able to fulfil the required digitisation tasks. Testing selected digitising equipment by means of specially designed targets proved however that potential buyers of equipment in the high cost range should be very cautious about suppliers' claims without proof of performance. Using targets to verify performance should be a routine check before any purchase. The study concludes with recommendations of implementing standards and it points to potential future research.
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Silva, Elisabeth Mary Cunha da. "Chemical and sensory investigations on the processing and preservation of a lamb product." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324852.
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Coon, Vicky Elizabeth. "An examination of information preservation in mental arithmetic performance for young and old adults." Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/28625.
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Apel, Theodore R. "Feature preservation and negated music in a phase vocoder sound representation." 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?p3303958.
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Thesis (Ph. D.)--University of California, San Diego, 2008.Title from first page of PDF file (viewed Jun. 17, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references: P. 92-98.
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Ndebele, Nothando Elizabeth. "Clustering algorithms and their effect on edge preservation in image compression." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1008210.
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Image compression aims to reduce the amount of data that is stored or transmitted for images. One technique that may be used to this end is vector quantization. Vectors may be used to represent images. Vector quantization reduces the number of vectors required for an image by representing a cluster of similar vectors by one typical vector that is part of a set of vectors referred to as the code book. For compression, for each image vector, only the closest codebook vector is stored or transmitted. For reconstruction, the image vectors are again replaced by the the closest codebook vectors. Hence vector quantization is a lossy compression technique and the quality of the reconstructed image depends strongly on the quality of the codebook. The design of the codebook is therefore an important part of the process. In this thesis we examine three clustering algorithms which can be used for codebook design in image compression: c-means (CM), fuzzy c-means (FCM) and learning vector quantization (LVQ). We give a description of these algorithms and their application to codebook design. Edges are an important part of the visual information contained in an image. It is essential therefore to use codebooks which allow an accurate representation of the edges. One of the shortcomings of using vector quantization is poor edge representation. We therefore carry out experiments using these algorithms to compare their edge preserving qualities. We also investigate the combination of these algorithms with classified vector quantization (CVQ) and the replication method (RM). Both these methods have been suggested as methods for improving edge representation. We use a cross validation approach to estimate the mean squared error to measure the performance of each of the algorithms and the edge preserving methods. The results reflect that the edges are less accurately represented than the non - edge areas when using CM, FCM and LVQ. The advantage of using CVQ is that the time taken for code book design is reduced particularly for CM and FCM. RM is found to be effective where the codebook is trained using a set that has larger proportions of edges than the test set.
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Maitree, Rapeepan, Gloria J. Guzman Perez-Carrillo, Joshua S. Shimony, H. Michael Gach, Anupama Chundury, Michael Roach, H. Harold Li, and Deshan Yang. "Adaptive anatomical preservation optimal denoising for radiation therapy daily MRI." SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS, 2017. http://hdl.handle.net/10150/626083.
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Low-field magnetic resonance imaging (MRI) has recently been integrated with radiation therapy systems to provide image guidance for daily cancer radiation treatments. The main benefit of the low-field strength is minimal electron return effects. The main disadvantage of low-field strength is increased image noise compared to diagnostic MRIs conducted at 1.5 T or higher. The increased image noise affects both the discernibility of soft tissues and the accuracy of further image processing tasks for both clinical and research applications, such as tumor tracking, feature analysis, image segmentation, and image registration. An innovative method, adaptive anatomical preservation optimal denoising (AAPOD), was developed for optimal image denoising, i. e., to maximally reduce noise while preserving the tissue boundaries. AAPOD employs a series of adaptive nonlocal mean (ANLM) denoising trials with increasing denoising filter strength (i. e., the block similarity filtering parameter in the ANLM algorithm), and then detects the tissue boundary losses on the differences of sequentially denoised images using a zero-crossing edge detection method. The optimal denoising filter strength per voxel is determined by identifying the denoising filter strength value at which boundary losses start to appear around the voxel. The final denoising result is generated by applying the ANLM denoising method with the optimal per-voxel denoising filter strengths. The experimental results demonstrated that AAPOD was capable of reducing noise adaptively and optimally while avoiding tissue boundary losses. AAPOD is useful for improving the quality of MRIs with low-contrast-to-noise ratios and could be applied to other medical imaging modalities, e.g., computed tomography. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
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Abdel, Karim Pia. "High pressure processing as an alternative food preservation technology and its applications for fruits and vegetables." Kansas State University, 2011. http://hdl.handle.net/2097/9958.
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Master of ScienceFood Science Institute
James L. Marsden
Consumers demand for high quality, natural and fresh tasting food, free from preservatives and additives, with a clean label and an extended shelf life has increased. High pressure processing (HPP), also known as high hydrostatic pressure, is a non-thermal food preservation technique that has the potential to meet these demands. It is an opportunity to preserve food, by applying intensive pressure in the range of 300-900 MPa, without adversely affecting organoleptic, textural and nutritional qualities as thermal processing like pasteurization and sterilization may do. In a typical high pressure batch cycle, the food prepackaged in a high-barrier flexible pouch or a plastic container is loaded into a perforated basket that goes into the pressure vessel; the pressure is then increased to the processing target pressure (come-up time); the product is held at the desired pressure for 3 to 10 minutes (pressure holding time); after which the pressure is released in usually few seconds (decompression time) and the product can be unloaded at this point. The pressure is applied uniformly in all directions simultaneously and this is known as isostatic pressure. Pressurization is usually accompanied by a moderate and uniform temperature increase called adiabatic heating. However, the food product usually rapidly returns to its initial temperature at decompression. With the recent shift in consumer lifestyle toward healthy living and healthier food, the consumption of raw fruits and vegetables has increased in popularity. However, as per the Centers of Disease Control and Prevention, fruits and vegetables have recently been associated with multiple foodborne disease outbreaks; the effect of high pressure processing on microbial safety, quality and sensory characteristics of fruits and vegetables has therefore been widely investigated as an alternative to traditional food processing and preservation methods. HPP inactivates microorganisms and quality-deteriorating enzymes and has limited effects on covalent bonds resulting in minimal modifications of food-quality attributes such as color, flavor and nutritional values. However, depending on the fruit or vegetable, high pressure could induce chemical or biochemical reactions that can affect their quality attributes.
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Zareifard, Mohammad Reza. "Evaluation of fluid-to-particle heat transfer coefficient under tube-flow conditions involving particle motion with relevance to aseptic processing." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ55397.pdf.
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Joseph, Mercy A. D. "Studies on the preservation of crab processing waste and evaluation of the quality of the protein from crab waste." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-06062008-152119/.
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Lekan, Michael D. "Impact of Bilateral Filter Parameters on Medical Image Noise Reduction and Edge Preservation." University of Toledo Health Science Campus / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=mco1263404507.
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Stefanova, Silvia. "Scalable Preservation, Reconstruction, and Querying of Databases in terms of Semantic Web Representations." Doctoral thesis, Uppsala universitet, Avdelningen för datalogi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-199573.
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This Thesis addresses how Semantic Web representations, in particular RDF, can enable flexible and scalable preservation, recreation, and querying of databases. An approach has been developed for selective scalable long-term archival of relational databases (RDBs) as RDF, implemented in the SAQ (Semantic Archive and Query) system. The archival of user-specified parts of an RDB is specified using an extension of SPARQL, A-SPARQL. SAQ automatically generates an RDF view of the RDB, the RD-view. The result of an archival query is RDF triples stored in: i) a data archive file containing the preserved RDB content, and ii) a schema archive file containing sufficient meta-data to reconstruct the archived database. To achieve scalable data preservation and recreation, SAQ uses special query rewriting optimizations for the archival queries. It was experimentally shown that they improve query execution and archival time compared with naïve processing. The performance of SAQ was compared with that of other systems supporting SPARQL queries to views of existing RDBs. When an archived RDB is to be recreated, the reloader module of SAQ first reads the schema archive file and executes a schema reconstruction algorithm to automatically construct the RDB schema. The thus created RDB is populated by reading the data archive and converting the read data into relational attribute values. For scalable recreation of RDF archived data we have developed the Triple Bulk Load (TBL) approach where the relational data is reconstructed by using the bulk load facility of the RDBMS. Our experiments show that the TBL approach is substantially faster than the naïve Insert Attribute Value (IAV) approach, despite the added sorting and post-processing. To view and query semi-structured Topic Maps data as RDF the prototype system TM-Viewer was implemented. A declarative RDF view of Topic Maps, the TM-view, is automatically generated by the TM-viewer using a developed conceptual schema for the Topic Maps data model. To achieve efficient query processing of SPARQL queries to the TM-view query rewrite transformations were developed and evaluated. It was shown that they significantly improve the query execution time.eSSENCE
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DUARTE, RENATO C. "Estudo dos compostos bioativos em especiarias (Syzygium aromaticum L, Cinnamomum zeylanicum Blume e Myristica fragans Houtt) processadas por radiação ionizante." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23593.
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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-03-17T10:35:55Z
No. of bitstreams: 0Made available in DSpace on 2015-03-17T10:35:55Z (GMT). No. of bitstreams: 0
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Basak, Sarmistha. "Studies on high pressure processing of orange juice : enzyme inactivation, microbial destruction, and quality changes, process verification and storage." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36874.
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High pressure (HP) processing has been emerging rapidly as a novel technique for non-thermal preservation of foods. Application of HP processing for shelf life extension of orange juice was the principal objective of the current research. To accomplish this objective, and to establish a scientific basis for HP processing of orange juice, a systemic approach was used which included the evaluation of: (a) HP inactivation kinetics of pectin methyl esterase (PME, the key enzyme in orange juice implicated with respect to quality changes), (b) destruction of spoilage microorganisms and changes in product quality, (c) HP process verification and finally, (d) storage studies on HP treated orange juice.In preliminary studies, the effect of HP treatment on indigenous microorganisms, texture and color of selected fresh fruits and vegetables were evaluated. Results showed that HP had a significant effect on the destruction of microorganisms. Product texture and color were mildly affected, often resembling the appearance of mildly heat-treated products.
Pressure induced inactivation kinetics of pectin methyl esterase (PME) was investigated at pH 3.7 and 3.2 in freshly squeezed single strength (12.6°Brix) and concentrated (10--40° Brix) orange juice. Results showed a biphasic nature of pressure induced inactivation of PME in both juices. The first phase consisted of rapid change in inactivation of enzyme, designated as instantaneous pressure kill (IPK), due to pulse pressurization, followed by gradual inactivation of enzyme, characterized by a first order rate of inactivation during pressure hold-time.
Combination treatment involving pressure cycle, pressure level and pressure hold-time was then evaluated for inactivation of PME using a response surface methodology. Overall, pressure pulse had a lower effect on inactivation of PME compared to other factors.
Pressure destruction kinetics of Leuconostoc mesenteroides and Saccharomyces cerevisiae the spoilage organisms in orange juice, were then investigated. Pressure destruction kinetics followed the same dual effect behavior, as observed with PME inactivation. IPK effect increased with pressure cycles and was more pronounced with S. cerevisiae that Leu. mesenteroides.
Storage studies of HP treated single strength and concentrated orange juice were conducted at selected temperatures (4, 10 and 20°C). Results showed that treated juice was microbiologically stable from a few days to several weeks depending on type of juice, storage temperature and processing conditions. (Abstract shortened by UMI.)
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Mussa, Dinna Mathemi. "High pressure processing of milk and muscle foods : evaluation of process kinetics, safety and quality changes." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35473.
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High pressure (HP) kinetics of the microbial destruction and changes in the physicochemical characteristics of milk and pork were studied. Raw milk samples containing indigenous microflora of approximately 106 CFU/mL were heat sealed in dual peel sterilization pouches and subjected to HP treatment from 150--400 MPa with holding times ranging 5--120 min. The kinetic parameters (rate constant, k and decimal reduction time, D) for the microorganisms, alkaline phosphatase, color and viscosity were evaluated, based on first order kinetics and the pressure dependence of kinetic parameters was evaluated using pressure destruction time (PDT) and Arrhenius models. Kinetic data was well described by the first order model (R 2 > 0.90).The application of pressure pulse was explored for pressure destruction of microorganisms as well as changes in physical-chemical characteristics of pork chops. Pork chops (2 days post-rigor) were subjected to HP treatment from 200--350 MPa for 0--120 min. Results showed that pressure changes of pork variables followed a dual effect consisting of an instantaneous pressure kill (IPK) with the application of pressure pulse (no holding) and a subsequent first order rate of destruction during the pressure hold time. The IPK values were pressure dependent and increased with pressure level. Parameters k and D indicated a higher rate of pressure destruction of microorganisms compared to quality attributes.
Kinetics of pressure destruction of Listeria monocytogenes Scott A were studied in relation to those of indigenous microorganism of milk and pork. The IPK was more pronounced with L. monocytogenes than with indigenous microflora. However, the kinetic parameters (k and D values) indicated a larger pressure resistance for L. monoctyogenes. HP processes were developed based on the standard plate count (SPC) kinetic data for indigenous microflora of milk as well as L. monocytogenes in milk and pork. The results showed that SPC kinetics permitted good estimation of microbial destruction in low pressure-lethality processes of milk and pork but its application at higher pressure-lethality levels were inaccurate. On the other hand, processes established based an destruction of L. monocytogenes were more predictable. Pressure pulse application to microbial lethality was also well predicted.
The shelf-life of milk and pork increased with the level of applied pressure lethality, but Q10 values suggested that low storage temperature was nevertheless required to control microbial growth and maintain quality. Storage of HP treated park offered some improvement in the texture but resulted in large color changes and drip losses. L. monocytogenes were not detected in any of the stored milk samples HP treated to achieve a lethality ≥10D.
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Chen, Cuiren 1962. "Application of computer simulation and artificial intelligence technologies for modeling and optimization of food thermal processing." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37877.
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The major objective of this project was to evaluate the feasibility of artificial neural networks (ANNs) and genetic algorithms (GAs) for modeling and optimization of food thermal processing. The specific objectives were: (1) to develop a comprehensive computer simulation program for thermal processing, (2) to apply ANNs and GAs for modeling and optimization of constant retort temperature (CRT) thermal processing and variable retort temperature (VRT) thermal processing, (3) to develop dynamic models for thermal processing using ANNs, and (4) to explore ANN-model-based analysis of critical control points for deviant thermal processes.As a preliminary research, neural network models were successfully developed for modeling of residence time distribution (RTD) under aseptic processing conditions. The main configuration parameters of neural networks such as the number of hidden layers and their neurons, learning runs, choice of transfer functions and learning rules were optimized.
In order to provide experimental data needed for developing and testing of ANN models and GA optimization, a comprehensive finite difference computer simulation program for thermal processing was first developed in MS Visual Basic language, which could be used for simulating different thermal processes such as constant retort temperature (CRT) and variable retort temperature (VRT) thermal processing.
The second objective was focused on developing modeling and optimization methods for CRT thermal processing using ANNs and GAs. The ANN models were developed for predicting process time, average quality retention, surface cook value, final temperature difference, lethality ratio, and equivalent energy consumption. Using this optimization program, the effects of process variables on the optimal retort temperature and the maximum average quality retention were investigated.
The final part of the thesis research was focused on applying ANN methods for the analysis of critical control points (CCPs) for deviant thermal processes, one of the important steps required for developing hazard analysis of critical control points (HACCP) program. The results indicated that ANN models could be efficiently used for the analysis of CCPs of thermal processing. Such a concept can be expanded for developing an ANN based HACCP expert system for thermal processing. (Abstract shortened by UMI.)
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TRINDADE, REGINALDO A. da. "Influência de antioxidantes naturais sobre o perfil lipídico de hambúrgueres bovinos submetidos à irradiação por sup(60)Co e aceleradores de elétrons." reponame:Repositório Institucional do IPEN, 2007. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11537.
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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Owusu-Manu, Michael. "Economic feasibility of minimally processed pork and fish in Quebec." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0005/MQ29760.pdf.
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Klokkernes, Torunn. "Skin processing technology in Eurasian reindeer cultures : a comparative study in material science of Sàmi and Evenk methods : perspectives on deterioration and preservation of museum artefacts : PhD thesis /." Rudkøbing [Denmark] : Langelands Museum, 2007. http://www.langelandsmuseum.dk/LMR%20Press/2007%20Klokkernes%20-%20Skin%20Processing%20LMR-PRESS.pdf.
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Zudaire, Villanueva Lorena. "Evaluación de diferentes estrategias químicas, físicas y biológicas para el desarrollo de productos vegetales de calidad enteros o mínimamente procesados." Doctoral thesis, Universitat de Lleida, 2018. http://hdl.handle.net/10803/663192.
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L’increment en la demanda de productes saludables i fàcils de consumir ha provocat un creixement de la producció i el disseny de nous productes mínimament processats (MP) basats en fruites i/o hortalisses. L'objectiu principal de la present tesi va ser estudiar l'efecte de diferents estratègies químiques, físiques i biològiques sobre la qualitat de dues matrius vegetals (pera i calçot) senceres i MP. Els tractaments aplicats en postcollita juntament amb els tractaments aplicats durant el processat mínim i conservació, van permetre obtenir dos productes d'IV gamma de gran qualitat amb una alta vida útil en refrigeració (4 ° C). Finalment, al llarg de la tesi es va avaluar l'efecte de la digestió in vitro simulada sobre les propietats antioxidants. Els resultats obtinguts van demostrar que la bioaccesibilitat del contingut total de fenols en la fase intestinal en peres i calçots va ser del 5-20% i 50%, respectivament.El incremento en la demanda de productos saludables y fáciles de consumir, ha hecho que crezca la producción y el diseño de nuevos productos mínimamente procesados (MP) basados en frutas y/o hortalizas. El objetivo principal de la presente tesis fue el estudio del efecto de diferentes estrategias químicas, físicas y biológicas sobre la calidad de dos matrices vegetales (pera y calçot) enteras y MP. Los tratamientos aplicados en poscosecha junto con los tratamientos aplicados durante el procesado mínimo y conservación, permitieron obtener dos productos de IV gama de gran calidad con una alta vida útil en refrigeración (4 °C). Por último, a lo largo de la tesis se evaluó el efecto de la digestión in vitro simulada sobre las propiedades antioxidantes. Los resultados obtenidos demostraron que la bioaccesibilidad del contenido total de fenoles en la fase intestinal en peras y calçots fue del 5-20 % y 50 %, respectivamente.
The increase in the demand for healthy and ready-to-eat products has led to the production and design of new minimally processed products based on fruits and/or vegetables. The main objective of the thesis was to study the effect of different chemical, physical and biological strategies on the quality of two whole and fresh-cut vegetable matrices (pear and calçot). The treatments applied in postharvest with the treatments applied during the minimal processing and conservation, led to a two high quality fresh-cut products with long shelf-life under refrigeration storage (4 ° C). Finally, throughout the thesis the effect of in vitro simulated digestion on the antioxidant properties was studied. The obtained results demonstrated that bioaccessibility of total phenolic content of pears and calçots was around 5-20 % and 50 % at the end of the intestinal phase, respectively.
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Paiva, Jônatas Lopes de. "Um algoritmo genético híbrido para supressão de ruídos em imagens." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-11042016-105926/.
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Imagens digitais são utilizadas para diversas finalidades, variando de uma simples foto com os amigos até a identificação de doenças em exames médicos. Por mais que as tecnologias de captura de imagens tenham evoluído, toda imagem adquirida digitalmente possui um ruído intrínseco a ela que normalmente é adquirido durante os processo de captura ou transmissão da imagem. O grande desafio neste tipo de problema consiste em recuperar a imagem perdendo o mínimo possível de características importantes da imagem, como cantos, bordas e texturas. Este trabalho propõe uma abordagem baseada em um Algoritmo Genético Híbrido (AGH) para lidar com este tipo de problema. O AGH combina um algoritmo genético com alguns dos melhores métodos de supressão de ruídos em imagens encontrados na literatura, utilizando-os como operadores de busca local. O AGH foi testado em imagens normalmente utilizadas como benchmark corrompidas com um ruído branco aditivo Gaussiano (N; 0), com diversos níveis de desvio padrão para o ruído. Seus resultados, medidos pelas métricas PSNR e SSIM, são comparados com os resultados obtidos por diferentes métodos. O AGH também foi testado para recuperar imagens SAR (Synthetic Aperture Radar), corrompidas com um ruído Speckle multiplicativo, e também teve seus resultados comparados com métodos especializados em recuperar imagens SAR. Através dessa abordagem híbrida, o AGH foi capaz de obter resultados competitivos em ambos os tipos de testes, chegando inclusive a obter melhores resultados em diversos casos em relação aos métodos da literatura.Digital images are used for many purposes, ranging from a simple picture with friends to the identification of diseases in medical exams. Even though the technology for acquiring pictures has been evolving, every image digitally acquired has a noise intrinsic to it that is normally gotten during the processes of transmission or capture of the image. A big challenge in this kind of problem consists in recovering the image while losing the minimum amount of important features of the image, such as corners, borders and textures. This work proposes an approach based on a Hybrid Genetic Algorithm (HGA) to deal with this kind of problem. The HGA combines a genetic algorithm with some of the best image denoising methods found in literature, using them as local search operators. The HGA was tested on benchmark images corrupted with an additive white Gaussian noise (N;0) with many levels of standard deviation for the noise. The HGAs results, which were measured by the PSNR and SSIM metrics, were compared to the results obtained by different methods. The HGA was also tested to recover SAR (Synthetic Aperture Radar) images that were corrupted by a multiplicative Speckle noise and had its results compared against the results by other methods specialized in recovering with SAR images. Through this hybrid approach, the HGA was able to obtain results competitive in both types of tests, even being able to obtain the best results in many cases, when compared to the other methods found in the literature.
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Higgins, Sean. "A Novel Method For Determining Acetabular Orientation." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/398.
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Enhanced knowledge of the acetabulum is of paramount importance in the diagnostic, planning, and execution stages of procedures and treatments targeting the hip joint. The convoluted and highly variable morphology of the structures comprising the bony pelvis make ascertaining measures of the acetabulum challenging. Furthermore, current methods for determining acetabular orientation assume symmetry between the separate halves of the pelvis by utilizing a coordinate system based on bilateral landmarks. The purpose of this study was to determine the three-dimensional orientation of the entire acetabulum. For this research, an improved programmatic method was developed for determining acetabular orientation using three-dimensional data. Accurate measures of commonly used acetabular orientation were ascertained from a large population of normal subjects. In addition, unilateral-based measures were performed using a new “hemi-pelvis coordinate system”. Significant differences between genders were observed in both the overall orientation of the acetabulum and the structural arrangement of the innominate bone.
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Trigo, Juliana Moreno. "Qualidade de mamão \'Formosa\' minimamente processado utilizando revestimentos comestíveis." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-20102010-163507/.
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Este trabalho teve como objetivo avaliar o efeito de revestimentos comestíveis na qualidade de mamão \'Formosa\' minimamente processado durante armazenamento a 5°C por 15 dias. Os tratamentos foram: o controle, e os seguintes revestimentos: amido de arroz 3%, alginato de sódio 0,5% e carboximetilcelulose 0,25%. O uso de revestimentos causou alterações nos parâmetros físicos, físico-químicos e microbiológicos do mamão minimamente processado, quando comparado ao controle. As alterações mais importantes foram: menor contagem de coliformes totais; menor respiração dos mamões tratados com amido de arroz e maior dos tratados com carboximetilcelulose, ao longo do tempo; menor descoloração da polpa dos frutos ao longo do armazenamento; maior manutenção da firmeza das amostras tratadas com carboximetilcelulose; e redução do teor de sólidos solúveis e aumento da acidez titulável. Os revestimentos não afetaram os atributos sensoriais. Como a maioria dos efeitos positivos das coberturas ocorreu no 12° e 15° dias e, considerando o custo da tecnologia relacionado ao preço dos revestimentos, a melhor opção, até 9 dias de armazenamento, consiste em fazer apenas uma boa sanitização dos frutos, como feito no controle. No entanto, se o interesse for preservar a vida útil dos mamões por um período maior, até 15 dias, os revestimentos testados podem ser utilizados com resultados satisfatórios.This study aimed to evaluate the effect of edible coatings on the quality of minimally processed \'Formosa\' papaya during storage at 5°C for 15 days. The treatments were: the control, and the following coatings: rice starch 3%, sodium alginate 0.5% and carboxymethylcellulose 0.25%. The use of coatings caused changes in the physical, physicochemical and microbiological parameters of minimally processed papaya, when compared to control. The most important changes were: lower counts of total coliforms; lower respiration of papayas treated with rice starch and higher of those treated with carboxymethylcellulose over time; less fruit pulp discoloration during storage, increased firmness maintenance of samples treated with carboxymethylcellulose; and reduction of soluble solids and increased acidity. The coatings did not affect the sensory attributes. Since most of the positive effects of the coatings occurred at the 12th and 15th days, and considering the technology cost related to the price of coatings, the best option, until 9 days of storage, is just to do a good sanitization of fruits such as that of control samples. However, if the interest is to preserve the shelf life of papayas for a longer period, up to 15 days, the coatings tested could be used with satisfactory results.
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Orth, Gabriela Previdello Ferreira. "Tratamento da informação nas artes digitais: uma abordagem contemporânea da documentação em meios tecnológicos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/27/27151/tde-04122013-230044/.
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Esta pesquisa aborda o tratamento da informação em ambientes digitais, tema que envolve o registro, a organização dos dados e dos acervos e a preservação das obras, considerando os meios tecnológicos existentes. Sua base teórica repousa no reconhecimento da Documentação e recorre também às teorias da Ciência da Informação, bem como na relação da organização do conhecimento com a tecnologia. Esse aporte é, por sua vez, relacionado ao campo da Arte e da Cultura Digital, considerando as peculiaridades das artes digitais, cujos trabalhos, geralmente realizados de forma colaborativa, são muitas vezes efêmeros, uma vez que disponibilizados para atualização. Considera-se que a maior dificuldade quanto ao tratamento das artes digitais é exatamente seu caráter paradoxal, uma vez que procura-se registrá-la mantendo a possibilidade de sua reutilização e/ou atualização. A metodologia utilizada é qualitativa e exploratória, mobilizando teorias de tratamento e exemplos concretos de organização adotados institucionalmente. Exploramos os conceitos de documento e documentação no âmbito da tecnologia e da arte e procuramos apresentar possibilidades de práticas documentais passíveis de serem utilizadas no trato de acervos e sistemas para a informação das artes digitais. A análise de casos concretos de sites de arte digital organizados por consórcios e outros tipos de instituições permite descrever os vários recursos informacionais utilizados, incluindo problemas de interoperabilidade e de preservação adotados. A sistematização das características das iniciativas analisadas permite identificar semelhanças e diferenças entre as formas de tratamento. Observamos que os ambientes de informação das artes digitais são estruturados de maneira complexa, uma vez que, além de utilizar mídias audiovisuais e tecnologias computacionais diversas, caracterizam-se por trabalhar com conteúdos heterogêneos e com uma diversidade de tipologias documentais.The subject matter of this research addresses information treatment in digital ambience. It involves data processing, collection organization and art works conservation, considering the existing technological media. Its Theoretical base grounds in Documentation, theories of Information Science, as well as knowledge organization and technology. On the other hand, this approach is related to both Digital Art and Culture, considering all art works singularities that due to the fact of being made in a collective way are often ephemeral. The paradoxical features found in digital art treatment are considered the harder issue, once one has to record it in order to its reuse and/or updating possibilities. The methodology used is qualitative and exploratory, working on information treatment theories and organization institutionally accepted examples. Debate about information condition and technology statute is considered the starting point in our analysis to qualify digital art in informational ambience. Document and documentation in art and technology sphere is explored. Nontraditional documentary practices possibilities are being considered in digital art information systems and collection treatment. Digital art sites made by consortiums and other organization cases analysis allows to describe several informational resources utilized, including interoperability and preservation troubleshooting adopted. We conclude that Digital art information ambience is structured in complex manners. Various audiovisual media and computational technologies are used to work with miscellaneous content and different types of documents.
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ALVES, RODRIGO M. "Segurança alimentar através da determinação de 2-alcilciclobutanonas em alimentos processados por radiação ionizante." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26942.
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A irradiação de alimentos é um meio de preservação de alimentos onde se utiliza uma técnica de processamento que expõe os alimentos a uma radiação ionizante controlada de alta energia. O tratamento realizado com o uso das radiações ionizantes em alimentos tem muitas aplicações tecnologicamente e tecnicamente viáveis incluindo a capacidade de melhorar a segurança microbiológica, reduzir os níveis de bactérias patogénicas, inibir a germinação de tubérculos, aplicação fitossanitária, conservar alimentos armazenados ou a estabilidade de armazenamento e também é utilizada para aumentar a vida de prateleira de determinados produtos devido à redução da contaminação por microrganismos. Em função do aumento do comércio internacional de alimentos e das crescentes exigências regulatórias dos mercados consumidores, cada vez mais países importadores e exportadores têm demonstrando interesse na irradiação de alimentos e desenvolvido pesquisas na aplicação prática desta tecnologia e de métodos de detecção do tratamento. Inúmeras pesquisas foram realizadas mundialmente, resultando em eficientes protocolos para identificar quais alimentos foram ou não irradiados. Até então, o \"mito\" que alimentos irradiados não poderiam ser detectados e que não eram formados quaisquer produtos únicos da radiação foi substituído pelo conhecimento que muitas mudanças podem ocorrer nos alimentos irradiados e essas mudanças poderiam ser utilizadas como ferramentas para identificar essa tecnologia. O processamento por radiação resulta em formações de padrões característicos de hidrocarbonetos saturados, aldeídos, metil e etil ésteres e 2-alcilciclobutanonas, dependendo da composição do ácido graxo do lipídio que compõe o alimento. Com isso a proposta do trabalho foi levantar dados para comparar os efeitos das diferentes doses de radiação gama e de elétrons em alimentos que possuem gordura para verificar as possíveis alterações decorrentes do uso da irradiação, como a presença de 2-Alcilciclobutanonas e também, mostrar os principais equipamentos utilizados para a irradiação de alimentos e suas categorias, com o objetivo de informar o publico em geral.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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As'ad, Hala. "Acoustic Beamformers and Their Applications in Hearing Aids." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/41540.
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This work introduces new binaural beamforming algorithms for hearing aids, with a robustness to errors in the estimate of the target speaker direction of arrival (DOA) and a good trade-off between noise reduction and preservation of the noise/interferers spatial impression. Three robust designs are proposed, and their robustness is confirmed by simulation results. These robust designs are a combination of binaural and monaural beamformers using two different microphone configurations: one for low frequency components and one for high frequency components. The robust designs are also found to be robust to mismatch between the anechoic propagation models used for the beamformers designs and the reverberant propagation models used to generate the signals at the microphones in the simulations. To preserve the binaural cues of the noise/interferers in the binaural beamformer outputs, a method based on a mixing/selection of different available binaural signals is proposed, using a classification from the phase and magnitude of a complex coherence function. This method is added as a post processor to the beamforming designs robust to target DOA mismatch. Simulation results show that the resulting mixed binaural output signals have a good binaural cues preservation level that outperform the benchmark design, with significant noise reduction and low target distortion. Since knowledge of source DOAs is important for beamforming noise reduction, a beamformer-based broadband multi-source DOA detection system is also developed in the thesis, using information from different frequencies or sub‐bands to obtain global estimates of sources DOAs. Simulation results shows that using one beamformer on each side is capable of detecting the DOAs of active sources under several acoustic scenarios, including scenarios with one, two, or three sources, and with or without the presence of some level of diffuse noise.
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Khadhraoui, Boutheina. "éco-extraction assistée par ultrasons des plantes médicinales : mécanisme(s), intensification et industrialisation ULTRASOUND TECHNOLOGY FOR FOOD PROCESSING, PRESERVATION AND EXTRACTION Histo-cytochemistry and scanning electron microscopy for studying spatial and temporal extraction of metabolites induced by ultrasound. Towards chain detexturation mechanism Microscopic imaging as a tool to target spatial and temporal extraction of bioactive compounds through ultrasound intensificationUltrason. Review of Alternative Solvents for Green Extraction of Food and Natural Green solvents for analytical chemistry." Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG0715.
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Le retour à la naturalité a favorisé le développement des compléments alimentaires à base de ressources végétales qui apparaissent comme un réservoir quasi-infini de nutriments et de substances naturelles bioactives. Ceci fait de l’extraction solide/liquide une étape incontournable au sein des industries intéressées par ce type de molécules. Avec les préoccupations environnementale set sociétales, il est devenu nécessaire d’inventer et développer de nouveaux procédés qui répondent aux six principes de l’éco-extraction. Cette démarche a totalement inspiré cette thèse qui a pour principal objectif le développement d’une technique d’éco-extraction assistée par ultrasons en substitution de la technique conventionnelle. Ce travail a permis de montrer qu’il était possible d’intensifier l’extraction de composés d’intérêt en utilisant les ultrasons avec une meilleure sélectivité et de meilleurs rendements d’extraction. Une attention particulière a été accordée à la compréhension des mécanismes d’action des ultrasons via une étude macroscopique et microscopique approfondie des structures végétales. Cette investigation a prouvé que les ultrasons agissent différemment en fonction des structures végétales et de leurs propriétés morphologiques et chimiques qui leur confèrent un degré de résistance plus ou moins important face à l’action des ultrasons. Partant de ces résultats, l’étude macroscopique et microscopique a été définie comme un outil de décision pour une extraction ciblée. Cette variabilité a été aussi constatée à l’échelle industrielle prouvant davantage l’importance de l’analyse microscopique. Enfin, le procédé d’extraction par ultrasons a été adopté à l’échelle industrielle pour ses performances d’extraction et pour son empreinte environnementale significativement réduite par rapport au procédé CV. Ce travail a également conduit à des travaux complémentaires sur l’étude du potentiel de solubilisation des produits naturels en vue d’une utilisation pour l’extraction de composés végétaux difficiles à solubiliser dans l’eau. Des résultats prometteurs ont été obtenus en termes de pouvoirs de solubilisation et d’extraction notamment à partir de la matière végétale broyée. Les résultats de cette dernière partie soulèvent cependant des questions qui pourraient faire l’objet de futures recherches et de perspectives pour ce travail qui sont principalement liés à l’étude des problèmes liés au changement du solvant et au prétraitement de la matière première et de la faisabilité industrielle de ce nouveau procédéWith recent trends in the increasing interest to environmental, economic and safety considerations,extraction techniques have largely focused on finding solutions with sustainable and green values toimplement in food processing, cosmetic and pharmaceutical industries. In this context, new “green”extraction techniques were developed such as Ultrasound-Assisted Extraction (UAE). The mainobjective of this thesis is industrial implementation of this new process in substitution to theconventional (CV) process. It has been shown in this work that the extraction of compounds ofinterest from rosemary and other plant matrices could be intensified using ultrasound, and thatdifferent performance gain could be achieved according to the plant matrix structural properties.Indeed, macroscopic and microscopic investigation of untreated and treated raw materials provedthat US act through different mechanisms and its resulting impacts can be extremely limited by plantstructural morphological and chemical properties, especially those of the specialized structures.Significant variability in performance gain was also observed at the industrial scale. Overall, USappears as a promising technique with a significant performance gain in terms of extraction yield andselectivity. Moreover, this process presents low environmental footprint compared to the CV one.Finally, it has been shown that natural products, such as honey and fruit juices, can be used toimprove solubilization and extraction of molecules that are poorly soluble in water. Encouragingresults were obtained in terms of solubilization and extraction abilities, especially from ground rawmaterials. However, these results raise questions related to the feasibility of industrialimplementation of this new process
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Boban, Bondžulić. "Процена квалитета слике и видеа кроз очување информација о градијенту." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=99807&source=NDLTD&language=en.
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У овој дисертацији разматране су објективне мере процене квалитетаслике и видеа са потпуним и делимичним референцирањем на изворнисигнал. За потребе евалуације квалитета развијене су поуздане,рачунски ефикасне мере, засноване на очувању информација оградијенту. Мере су тестиране на великом броју тест слика и видеосеквенци, различитих типова и степена деградације. Поред јавнодоступних база слика и видео секвенци, за потребе истраживањаформиране су и нове базе видео секвенци са преко 300 релевантнихтест узорака. Поређењем доступних субјективних и објективних скороваквалитета показано је да је објективна евалуација квалитета веомасложен проблем, али га је могуће решити и доћи до високихперформанси коришћењем предложених мера процене квалитета сликеи видеа.U ovoj disertaciji razmatrane su objektivne mere procene kvalitetaslike i videa sa potpunim i delimičnim referenciranjem na izvornisignal. Za potrebe evaluacije kvaliteta razvijene su pouzdane,računski efikasne mere, zasnovane na očuvanju informacija ogradijentu. Mere su testirane na velikom broju test slika i videosekvenci, različitih tipova i stepena degradacije. Pored javnodostupnih baza slika i video sekvenci, za potrebe istraživanjaformirane su i nove baze video sekvenci sa preko 300 relevantnihtest uzoraka. Poređenjem dostupnih subjektivnih i objektivnih skorovakvaliteta pokazano je da je objektivna evaluacija kvaliteta veomasložen problem, ali ga je moguće rešiti i doći do visokihperformansi korišćenjem predloženih mera procene kvaliteta slikei videa.
This thesis presents an investigation into objective image and video qualityassessment with full and reduced reference on original (source) signal. Forquality evaluation purposes, reliable, computational efficient, gradient-basedmeasures are developed. Proposed measures are tested on different imageand video datasets, with various types of distorsions and degradation levels.Along with publicly available image and video quality datasets, new videoquality datasets are maded, with more than 300 relevant test samples.Through comparison between available subjective and objective qualityscores it has been shown that objective quality evaluation is highly complexproblem, but it is possible to resolve it and acchieve high performance usingproposed quality measures.
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Cardillo, Enrico. "HBIM methodology for structural preservation of historical buildings: the semantic modeling of the San Felice sul Panaro fortress." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Building Information Modelling is changing the design and construction field ever since it entered the market. It took just some time to show its capabilities, it takes some time to be mastered before it could be used expressing all its best features.
Since it was conceived to be adopted from the earliest stage of design to get the maximum from the decisional project, it still struggles to adapt to existing buildings. In fact, there is a branch of this methodology that is dedicated to what has been already made that is called Historic BIM or HBIM.
This study aims to make clear what are BIM and HBIM, both from a theoretical point of view and in practice, applying from scratch the state of the art to a case study. It had been chosen the fortress of San Felice sul Panaro, a marvellous building with a thousand years of history in its bricks, that suffered violent earthquakes, but it is still standing.
By means of this example, it will be shown which are the limits that could be encountered when applying BIM methodology to existing heritage, moreover will be pointed out all the new features that a simple 2D design could not achieve.
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Castellucci, Claudia Moreira Nery. "Influência do método de cocção no valor nutritivo, qualidade lipídica e formação de óxidos de colesterol em lingüiças calabresas à vácuo e granel." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/89/89131/tde-04052015-181117/.
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Os óxidos de colesterol estão presentes em diversas preparações alimentares, especialmente aquelas que contêm altos níveis de colesterol (exemplo: ovo, leite, carne e produtos marinhos). A formação de óxidos de colesterol é influenciada pelo calor (especialmente por um período muito longo), oxigênio, luz e UV, atividade de água, presença de ácidos graxos insaturados. Dentre os diferentes produtos cárneos existentes, temos os embutidos, ou carnes preparadas embutidas. A procura por produtos cárneos com menores taxas de oxidação e mais saudáveis é uma preocupação mundial. O efeito do processamento térmico dos alimentos sobre a formação dos óxidos de colesterol vem sendo investigado. Evidências sugerem que o tempo e a temperatura são fatores determinantes neste processo, influenciando diretamente na taxa de oxidação de colesterol. A presente pesquisa teve por objetivo: avaliar o valor nutritivo, qualidade lipídica e formação de óxidos de colesterol em Lingüiças Calabresas à vácuo e granel. Os valores médios de umidade, proteínas e minerais (cinzas) foram determinados, quantitativamente, conforme metodologia do ADOLFO LUTZ (1985) e AOAC (1995). Os valores de carboidratos foram determinados por diferença utilizando coeficientes para KCal e KJ (WATT&MERRILL, 1963, SLIMANI et al., 2000). Para a determinação dos lipídios totais utilizou-se a metodologia de MARMER & MAXWELL (1981). Para quantificar o TBA seguiu-se o método de TARLADGS et al. (1964), modificado por CRACKEL et al. (1988), adaptado por TORRES & OKANI (1997). Os ácidos graxos foram determinados seguindo MARMER & MAXWELL (1981) e MORRISON & SMITH (1974). O colesterol e óxidos de colesterol foram determinados seguindo os passos de MARMER & MAXWELL (1981), CSALLANY et al. (1989) e CHEN & CHEN (1994). Para a validação da metodologia para o HPLC foram realizados ensaios de recuperação, precisão, linearidade, limite de detecção e quantificação. Para a análise estatística foi realizado média, desvio padrão, análise de variância e complementada com comparações múltiplas de Bonferroni utilizando o Software SPSS. Os resultados obtidos das análises realizadas foram que o tipo de preparo influenciou no teor de umidade das lingüiças (crua - 65,47g; frita - 53,65, grelhada 58,31g). As amostras da embalagem a vácuo (22,91 g) apresentaram maior quantidade de proteína que as amostras da embalagem a granel (20,25g). Os valores de carboidratos não variaram em função da amostra ser da embalagem a vácuo ou granel. As amostras mais calóricas foram as fritas (242,89 KCal ou 1195,22 KJ) seguida pelas amostras grelhadas (212,41 KCal ou 1083,55 KJ). Não se observou variação da atividade de água nas amostras entre as embalagens estudadas. O tipo de preparo provocou alterações nos valores de TBA, mas não promoveu sabor rancificado nas amostras (crua - 0,06 mgMA/Kg, frito - 0,08mgMA/Kg e grelhado - 0,143mgMA/Kg). O teor de lipídios e colesterol não sofreram alterações em função do tipo de preparo. Os óxidos de colesterol 7-ceto,7α-OH, 7β-OH somente apresentaram traços em todas as variáveis analisadas (preparo, lote, embalagem e procedência). O óxido 25-OH apareceu em todas as preparações, crua (3,05µg/g), frito (3,76µg/g) e grelhado (2,14µg/g). Os resultados mostraram que a as amostras da embalagem vácuo apresentavam quantidade média de 25-OH menor que as da embalagem a granel. As amostras da embalagem a vácuo apresentaram o seguinte perfil de ácidos graxos: 51,04% de saturados e 48,96% de insaturados, enquanto que as amostras da embalagem granel apresentaram 38,18% de saturados e 61,82% de insaturados. Os resultados permitiram concluir que: a) o teor de umidade, proteína, cinzas, carboidratos, calorias, Aw (AA) e pH sofreram alterações quando submetidos aos 3 tipos de preparo e tipo de embalagem; b) os valores obtidos para TBA indicam que as amostras não apresentavam rancidez quando crua e após os vários preparos; c) as lingüiças apresentaram somente traços de 7-ceto, 7α-OH e7β-OH; d) as amostras de lingüiças calabresas quando submetidas a diversos métodos de cocção apresentaram diferentes concentrações de 25-OH; e) a quantidade de 25-OH variava de acordo com o tipo de processamento e este se tornava mais oxidado quando submetido ao processo de fritar; f) as amostras provenientes da embalagem a granel apresentaram maiores valores de 25-OH; g) o perfil de ácidos graxos não apresentou variação quando as amostras eram submetidas a diferentes preparos; h) as amostras da embalagem a vácuo apresentavam mais ácidos graxos saturados e as amostras da embalagem a granel apresentavam mais ácidos graxos insaturados.The cholesterol oxides are present in several alimentary preparations, especially those that contain high cholesterol levels (example: egg, milk, meat and marine products). The formation of cholesterol oxides is influenced by the heat (especially for a very long period), oxygen, shines and UV, activity of water, presence of unsaturated fatty acids. Among the different meat products, we have the sausages, or built-in prepared meats. The search for meat products with smaller oxidation rates and healthier it is a world concern. The effect of the thermal processing of the victuals about the formation of the cholesterol oxides comes being investigated. Evidences suggest that the time and the temperature are decisive factors in this process, influencing direct1y in the rate of cholesterol oxidation. The present research had for objective: to evaluate the nutritive values, lipid quality and formation of cholesterol oxides in \'Lingüiças Calabresas\' to vacuum and bulk packaging. The medium values of moisture, proteins and minerals (ash) were determinated, quantitativity, according to methodology of ADOLFO LUTZ (1985) and AOAC (1995). The carbohydrates values were certain for difference using coefficients for KCal and KJ (WATT &MERRILL, 1963, SLIMANI et al., 2000). For the determination of the lipids the methodology of MARMER & MAXWELL (1981) was used. To quantify TBA the method of TARLADGS et al. was proceeded (1964), modified by CRACKEL et al. (1988), adapted by TOWERS & OKANI (1997). The fatty acids was certain following MARMER & MAXWELL (1981) and MORRISON & SMITH (1974). The cholesterol and cholesterol oxides were certain following the steps of MARMER & MAXWELL (1981), CSALLANY et al. (1989) and CHEN & CHEN (1994). For the validation of the methodology for HPLC recovery, precision, linearity, detection limit and quantification were accomplished. For the statistical analysis average, standard deviation, was accomplished variance analysis and complemented with multiple comparisons of Bonferroni using the Software SPSS. The obtained results of the accomplished analyses were that the type of prepare influenced in the moisture of the lingüiças (raw - 65,47g; fried - 53,65, grilled - 58,31g). The samples of the vaccum packaging (22,91g) presented larger amount of protein than the samples of the bulk packaging (20,25g). The carbohydrates values didn\'t vary in function of the sample to be of the vacuum or bulk packaging. The most calorific samples were the fried ones (242,89 KCal or 1195,22 KJ) followed by the grilled samples (212,41 KCal or 1083,55 KJ). The variation of the activity of water was not observed in the samples among the studied packagings. The type of prepare promoved alterations in the TBA values, but it didn\'t promote rancidity flavor in · the samples (raw - 0,06 mgMA/Kg, fried -0,08mgMA/Kg and grilled - 0,143mgMA/Kg). The lipidis and cholesterol didn\'t suffer alterations in function of the type of prepare. The cholesterol oxides 7-ceto, 7α-OH, 7β-OH only presented lines in whole the analyzed variables (prepare, lot, packaging and origin). The oxide 25-OH appeared in all the preparations, raw (3,05µg/g), fried (3,763µg/g) and grilled (3,11µg/g). The results showed that to the samples of the bulk packaging presented larger medium amount of 25-OH than the one of the vaccum packaging. The samples of the vaccum packaging presented the following profile of fatty acids: 51,04% saturated and 48,96% of unsaturated, while the samples of the bulk packaging presented 38,18% saturated and 61,82% unsaturated. The results allowed that: a) moisture, protein, ash, carbohydrates, energy value, Aw (AA) and pH suffered alterations when submitted to the 3 types of prepare and packaging type; b) the values obtained for TBA indicate that the samples didn\'t present rancidity flavor when raw and after the several prepares; c) the lingüiças presented only lines of 7-ceto, 7α-OH, 7β-OH; d) the samples of Linguiça Calabresa when submitted to several cooking methods they presented different concentrations of 25-OH and the amount of 25-OH varied in agreement with the processing type and this became oxidized when submitted to the frying process; f) the samples of the bulk packaging presented larger values of 25-OH; g) the profile of fatty acids didn\'t present variation when the samples were submitted the different prepares; h) the samples of the vaccum packaging presented more saturated fatty acids and the samples of the bulk packaging presented more unsaturated fatty acids.
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Nunes, Tatiana Pacheco. "Efeito da pré-cura na estabilidade microbiológica de carne mecanicamente separada e elaboração de um produto reestruturado com filés de peito de galinhas de descarte." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-20102003-161041/.
Full textAbstract:
Os peitos de galinhas matrizes pesadas de corte, poedeiras comerciais brancas e frangos foram desossados manualmente, com o objetivo de avaliar e comparar as propriedades tecnológicas capacidade de retenção de água e de emulsificação bem como pH e composição centesimal, além de elaborar e avaliar sensorialmente um produto reestruturado empanado, tipo nugget. Os resultados das análises indicaram que não houve diferença significativa entre as carnes analisadas, nem entre produtos processados, implicando utilização regular desse tipo de matéria-prima na indústria de alimentos. O restante das carcaças das galinhas foi utilizado para extração de carne mecanicamente separada (CMS) para avaliação da estabilidade microbiológica. As CMSs foram submetidas a dois tratamentos: I) com 150ppm de nitrito, embaladas em saco de polietileno; e II) com 150ppm de nitrito e 500ppm de eritorbato, embaladas em saco de polietileno. Como controle, as amostras de CMS foram apenas acondicionadas em sacos de polietileno. Todas as embalagens foram estocadas e congeladas a 18ºC por 99 dias. Os resultados da análise de caracterização microbiológica indicaram que tanto as amostras de CMS de galinha matriz quanto de galinha poedeira atenderam os padrões de contagem requeridos pela legislação Brasileira. A avaliação da estabilidade microbiológica das CMSs no primeiro e no último dia para mesófilos, Escherichia coli, Staphylococcus aureus, Clostridium perfringens e Pseudomonas, bem como as análises quinzenais de microrganismos psicrotróficos, indicaram que não houve uma redução significativa nas contagens, independentemente do tratamento aplicado. Não foi detectada Salmonella em nenhuma das amostras analisadas. Tais resultados apontaram o tempo de estocagem como o principal fator na redução da carga bacteriana.The breasts of heavy fowls, white commercial egg-layers and chickens were manually deboned in order to evaluate and compare technological propertieswater hold and emulsifying capacityand pH and centesimal composition, as well as to prepare and assess a restructured coated product. The results of the analyses indicated that there was not a significant difference between the meats analyzed, nor among the processed products, implying the regular use of such meat in the food industry. The remaining parts of the hens carcasses were mechanically deboned for the evaluation of microbiological stability. The mechanically deboned meat (MDM) was submitted to two treatments: I) 150ppm of nitrite, packed in polyethylene bags; II) 150ppm of nitrite and 500ppm of erythorbate, packed in polyethylene bags. The control meats were just packed in polyethylene bags. All samples were frozen-stored at 18ºC for 99 days. The results of microbiological characterization indicated that both samples from heavy fowls and egg-layers were in accordance with the Brazilian legislation. MDM microbiological stability evaluation on the first and last days for fecal coliforms, mesophiles, Staphylococcus aureus, Clostridium perfringens and Pseudomonas, as well as the analyses carried out every fifteen days for psychrotrophics bacteria indicated that there was not a significant reduction in the presence of the above, irrespective of the treatment applied. Salmonella was not detected in any of the samples. Such results indicated that freezing storage period was the main factor responsible for the reduction of the bacterial count in MDM.
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Chen, Ruey-Cheng, and 陳瑞呈. "Information preservation and its applications to natural language processing." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/03491820942043201169.
Full textAbstract:
博士國立臺灣大學
資訊工程學研究所
101
In this dissertation, we motivate a mathematical concept, called information preservation, in the context of probabilistic modeling. Our approach provides a common ground for relating various optimization principles, such as maximum and minimum entropy methods. In this framework, we make explicit an assumption that the model induction is a directed process toward some reference hypothesis. To verify this theory, we conducted extensive empirical studies to unsupervised word segmentation and static index pruning. In unsupervised word segmentation, our approach has significantly boosted the segmentation accuracy of an ordinary compression-based method and achieved comparable performance to several state-of-the-art methods in terms of efficiency and effectiveness. For static index pruning, the proposed information-based measure has achieved state-of-the-art performance, and it has done so more efficiently than the other methods. Our approach to model induction has also led to new discovery, such as a new regularization method for cluster analysis. We expect that this deepened understanding about the induction principles may produce new methodologies towards probabilistic modeling, and eventually lead to breakthrough in natural language processing.
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黃書政. "Application of Hurdle Technology on Chinese Sausage Processing and Preservation." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/31733625041030646293.
Full textAbstract:
碩士國立海洋大學
食品科學系碩士在職專班
89
Chinese sausage is a popular product in Taiwan. The preserves are usually added in the product to extend it’s shelf-life. However, the amount used in some commercial products is over the limit. Therefore, in this study we apply the hurdle technology to Chinese sausage processing and preservation instead of single method to improve its quality. Generally, the quality indices of Chinese sausage were represented by the measuring of the color ( a value ) and bacteria (TPC). Among 10 additives used in this study, glucono-delta-lactone, propylene glycol, sodium lactate, potassium sorbate had a more significant effect on the inhibition of bacteria. Therefore, three additives glucono-delta-lactone, propylene glycol, sodium lactate were used as the hurdle factors. To employ these factors systematically, the experiments were designed by using response surface method (RSM). A central rotatable design three-variable and three-level was adopted. The amount of glucono-delta-lactone (0.4％), propylene glycol (0.5％), sodium lactate (1.75％) and potassium sorbate (0.1％) with ±50％ were added to evaluate their combined effect on sausage quality. The results showed the optimal condition for the quality of vacuum packaged Chinese sausage stored at 4℃ was propylene glycol 0.5％, glucono-delta-lactone 0.70∼0.80％ and sodium lactate 1.75∼2.70％. If potassium sorbate was proposed as a factor, the optimal condition was sodium lactate 1.75％, glucono-delta-lactone 0.40∼0.80％ and potassium sorbate 0.18∼0.20％. On the other head, the optimal condition for atmosphere package sausage stored at 25℃ was propylene glycol 0.5％, glucono-delta-lactone 0.50∼0.80％ and sodium lactate 1.00∼3.00％. If potassium sorbate was used, the addition of sodium lactate 1.75％, glucono-delta-lactone 0.40∼0.70％ and potassium sorbate 0.18∼0.20％ could obtain a similar result. There is no significant difference of sensory evaluation between the conventional sausage and the product processed by hurdle technology. However, the latter product had a longer shelf-life than the former.
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Rodakowski, Andrea M. "Sensory changes in high pressure processed vs. heat processed food systems over time." Thesis, 1999. http://hdl.handle.net/1957/26557.
Full textAbstract:
This study was undertaken to determine the sensory differences in high pressure vs. heat
processed food systems after storage at ambient and refrigerated temperatures as
determined by a trained sensory panel. Spanish rice and spaghetti with meat sauce were
prepared and treated with heat and with high pressure processing (HHP). A citrus fruit
mix consisting of pieces of orange, grapefruit, and pineapple was processed by mild heat
and HHP, and heat alone.
One day after processing, treated products were tested along with untreated
controls. Products were stored at either 22°C or 3°C, and tested at 10, 30, 60, 90, and
120 days. Sensory testing was done by a panel trained in a QDA-type method, and data
was analyzed by univariate and multivariate methods.
For spaghetti with meat sauce, significant differences (p>0.05) were found between
processing methods stored at the same temperature in appearance and texture attributes,
with the high pressure processed samples closer to unstored product than those treated by
heat. Differences in treatments first appeared in 'dry appearance' at 10 days, and by 120
days there were differences in 'tomato integrity', 'pasta integrity', 'brightness of color', and 'firmness of pasta' as well. Most of these differences were due to the stickiness
caused by the extra amylose leaking out of the heat treated pasta over time.
For Spanish rice, there were no statistically significant differences between
samples processed by the two methods and stored at the same temperature. The Spanish
rice was formulated with parboiled rice, which allows very little amylose leakage, so it
did not show amylose-related effects as the spaghetti with meat sauce did.
The fruit mix processed with HPP and mild heat had significantly higher ratings
in appearance attributes 'brightness of color' and piece integrity', and lower ratings in
'cooked' descriptors than product treated with heat alone stored at the same temperature.Graduation date: 2000
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Chen, Shao-Lan, and 陳韶嵐. "Application of high pressure processing on seafood for preservation and food safety elevation." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xgn3nb.
Full textAbstract:
碩士國立高雄科技大學
水產食品科學系
107
High pressure processing (HPP) is an emerging non-thermal technology that can inactivate pathogenic and spoilage microorganisms in food, and extend the shelf life of foods. Histamine is primarily produced in fish via decarboxylation of free histidine by the activity of various species of histamine-forming bacteria (HFB). Scombroid fish included tuna, mackerel, and bonito, are the type of fish commonly involved in scombroid poisoning due to the high levels of free histidine in their muscle tissue. This study was to determine the effects of HPP treatments on inhibitory effects of histamine-forming bacteria (HFB) such as G(+) Staphylococcus capitis, and G(-) Enterobacter aerogenes. The result showed that bacterial counts of HFB subjected to HPP decreased with increasing pressure level and holding time. HFB had a higher D value in marlin meat slurry compared with that in phosphate buffer, indicating that the HFB were more resistant to pressure in marlin meat slurry. In phosphate buffer, S. capitis was more resistant than E. aerogenes at lower pressure (< 380 MPa), whereas E. aerogenes was more resistant than S. capitis at higher pressure (> 380 MPa). In marlin meat slurry, S. capitis had a higher D-value than E. aerogenes at the same pressure, indicating it was more resistant at HPP treatment. In addition, the changes of aerobic plate count (APC), total volatile basic nitrogen (TVBN), pH value and histamine contents in marlin meat after HPP treatment during storage at different temperatures (4 ℃, 15 ℃ and 25 ℃) were evaluated. The APC of marlin meat after HPP treatment (200-500 MPa for 5 min) decreased with increased pressure from 4.94 ± 0.12 log CFU/g (control) to 2.36 ± 0.08 log CFU/g (500 MPa). In color of marlin meat, L* value (lightness) increased significantly with increased pressure, whereas a* value (redness) was significantly reduced with increased pressure. In general, the HPP treatment combined with storage at 4 ℃ and 15 ℃ significantly retarded the increase of APC, TVBN and histamine contents in marlin meat. The reactivity with monoclonal antibody against fish allergen and protein content of mackerel meat extract by HPP treatment (200 MPa and 600 MPa for 1-15 min) were studied. The HPP of 200 MPa treatment did not change the reactivity with monoclonal antibody against fish allergen and protein content of fish extract, whereas the reactivity and protein content significantly decreased after 600 MPa treatment. In summary, this result suggested the marlin meat treated with HPP and stored at below 15 ℃ could prevent deterioration of product quality, extend shelf life, and reduce histamine fish poisoning risk. Meanwhile, it reduces reactivity with monoclonal antibody against fish allergen in mackerel meat after 600 MPa treatment.
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Jaczynski, Jacek. "Physicochemical and microbiological characteristics of surimi seafood under thermal and E-beam processing." Thesis, 2002. http://hdl.handle.net/1957/25940.
Full textAbstract:
Effects of thermal and electron beam (e-beam) processing on microbial
inactivation and physichochemical properties of surimi and surimi seafood were
investigated. Thermal-death-time (TDT) concept was used to model
Staphylococcus aureus inactivation by heat and e-beam. Gurney-Lurie charts were
used to estimate temperature during thermal processing of surimi seafood. Dose
mapping technique was used to estimate dose absorbed by surmi seafood during e-beam
processing. The dose absorbed increased up to 2 cm and then it gradually
decreased, reaching a minimum at 5 cm depth of surimi seafood. It was determined
that one and two-sided e-beam can efficiently penetrate 3.3 and 8.2 cm of surimi
seafood, respectively. The D-value for thermally inactivated S. aureus was 0.65,
1.53, 6.52, 49.83, and 971.54 s, at 95, 85, 75, 65, and 55°C, respectively. The D-value
for S. aureus inactivated with e-beam was 0.34 kGy. The z-value for
thermally inactivated S. aureus between 55-95°C was not linear. Thermal
processing degraded texture and color of surimi seafood. E-beam enhanced
firmness and decreased the b* value of surimi seafood. Myosin heavy chain
(MHC) degraded proportionally to the e-beam dose. Actin was not affected by e-beam
except treatment at 25 kGy. Hydrophobic interactions and disulfide bonds
were formed in raw Alaska pollock surimi when treated with e-beam.Graduation date: 2002
40
Gowda, B. Sadashive. "Analytical And Experimental Study Of Bulk Precooling Of Food Products." Thesis, 1996. http://etd.iisc.ernet.in/handle/2005/1711.
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Miskovsky, Anna Marie. "Effects of processing and storage on nutritional quality of soybean curd." 1986. http://hdl.handle.net/2097/22116.
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Hsue, Kuo-Chiang, and 徐國強. "Effect of High Pressure Storage at Normal Temperature on Freshness Preservation and Processing Quality of Tilapia Muscle." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/32202410952733498055.
Full textAbstract:
碩士國立中興大學
食品科學系
86
AbstractMuscle of tilapia（Orechromis niloticus）was stored under high hydrostatic pressure from 500 to 3,000 atm for 12 hr at 25℃ to investigate the changes of freshness and the denaturation of muscle proteins. The tilapia muscle after pressurizing was also stored at normal condition（25℃, 1 atm） to determine the changes of K values and microorganism numbers in order to investigate the effect of high pressure on the inhibition of putrefactive factors in the muscle. The results obtained were as follows:1. The pH of tilapia muscle stored at lower pressure（500-1,000 atm） decreased, but pH increased for that was stored over 1,000 atm. pH of the muscle did not change apparently with elongating time. The phenomenon indicated that the development of rigor mortis of pressurized tilapia muscle was not obvious.2. K value of tilapia muscle stored under high pressure increased slower than those stored at normal condition. The result indicated that pressure can keep the freshness of tilapia muscle.3. VBN of tilapia muscle stored at normal condition increased during storage. However, VBN was similar to that of fresh muscle when the storing pressure was higher than 2,000 atm.4. The "L" , "b" values and white index of tilapia muscle stored under high pressure increased rapidly with increasing pressure, but "a" value was the reverse. The appearance of tilapia muscle turned white in high pressure.5. Total plate counts and psychrophilic bacteria counts in tilapia muscle stored under high pressure decreased with increasing time. Psychrophilic bacteria would be killed when the muscle was stored at the pressure over 2,000 atm.6. The gel-forming property of tilapia muscle stored at 500 atm increased, but a decreasing trend was observed from 1,000 to 3,000 atm. Storage under pressure higher than 1,000 atm would result tilapia muscle in decrease of its processing quality.7. The extraction of tilapia actomyosin decreased with increasing pressure, and it was below 10% when the treating pressure was higher than 2,000 atm. But the activity of actomyosin Ca-ATPase from tilapia muscle stored under high pressure was still maintained.8. According to the analysis of protein solubility, DSC, SEM, and SDS-PAGE, the critical pressure induced tilapia protein denaturation was about 2,000 atm.9. The putrefactive factors of tilapia muscle were inhibited but not entirely destroyed during pressure storage. The result indicated that tilapia muscle had to be stored jointly with other ways after high pressure storage to maintain its freshness and processing property.
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Xu, Guo-Qiang, and 徐國強. "Effect of High Pressure Storage at Normal Temperature on Freshness Preservation and Processing Quality of Tilapia Muscle." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/99117024224197750028.
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Ren, Haiyu. "Effect of cell wall degrading enzymes and chemicals on corn stover preservation and pretreatment during ensilage processing." 2006. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-1281/index.html.
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Zeng, Siang-Mei, and 曾湘媚. "High pressure processing combined with thyme essential oil on sterilization histamine-forming bacteria and preservation application of marlin meat." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/aa77tf.
Full textAbstract:
碩士國立高雄科技大學
水產食品科學系
107
Histamine is primarily produced in fish via decarboxylation of free histidine by the activity of various species of histamine-forming bacteria (HFB). Some fish included marlin, tuna, mackerel, and bonito, are the type of fish commonly involved in histamine fish poisoning. High pressure processing (HPP) is an emerging non-thermal technology that can inactivate pathogenic and spoilage microorganisms in food, and extend the shelf life of foods. Plant essential oils components are gaining a wide interest in health industry for their potential as antioxidant and antimicrobial agents, as they are generally recognized as safe. Hurdle technology is a method that uses a combination of two or more physical or chemical preservation techniques to eliminate pathogens and increase the shelf life of foods instead of chemical preservatives and bactericidal agents. In recent years, the use of natural extracts to replace chemical agents has become popular and has been proven to have an antibacterial effect. In the food industry, the addition of essential oils to foods can not only increase the flavor of the products, but also enhance the antibacterial properties of the products. This study was to determine the effects of thyme essential oil (TEO) combined with HPP treatments on inhibitory effects of HFB such as Enterobacter aerogenes and Staphylococcus capitis. The result showed that bacterial counts of HFB subjected to HPP decreased with increasing pressure level and holding time. HFB had a higher D value in marlin meat slurry compared with that in phosphate buffer, indicating that the HFB were more resistant to pressure in marlin meat slurry. E. aerogenes had a higher D value than S. capitis in phosphate buffer, whereas S. capitis had a higher D-value than E. aerogenes at the same pressure in marlin meat slurry, indicating it was more resistant at HPP treatment. In addition, the aerobic plate count (APC) of raw marlin meat after TEO combined with HPP treatment decreased with increased pressure from 5.66 Log CFU/g (control) to 3.61 Log CFU/g (500 MPa, 5 min). In color of marlin meat, L* value (lightness) increased significantly with increased pressure, whereas a* value (redness) was significantly reduced with increased pressure. In general, the TEO combined with HPP treatments (>200 MPa) significantly retarded the increase of APC, total volatile basic nitrogen (TVBN) and histamine contents in marlin meat stored at 4 oC and 15 oC, regardless of non-inoculated or inoculated with E. aerogenes samples. However, the APC and TVBN levels were retarded, and histamine was completely inhibited in TEO combined with HPP samples (>300 MPa) stored at 4 oC. In summary, this result suggested the marlin meats treated with TEO combined with HPP treatments and stored at below 15 oC could prevent deterioration of product quality, extend shelf life, and reduce histamine hazard and risk.
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Thawornchinsombut, Supawan. "Biochemical and gelation properties of fish protein isolate prepared under various pH and ionic strength conditions." Thesis, 2004. http://hdl.handle.net/1957/26451.
Full textAbstract:
A novel method for isolating fish proteins by shifting pH to high acid or high
alkali pH was the focus of the study. Biochemical and physicochemical properties of
various pH-treated soluble fish proteins as a function of ionic strength were
determined. Effect of ionic strength and various storage conditions on gelation
properties and stabilization of fish protein isolate (FPI) were also elucidated.
At low ionic strength (IS 10 mM NaCl), the solubility of Pacific whiting (PW)
proteins was low between pH 5 and 10, but increased significantly as the pH was
shifted to either acidic or alkaline pH. The isoelectric point (pi) shifted toward
acidic direction as IS increased to 600 mM. High IS (600 mM NaCl) resulted in
protein aggregation at low pH but improved myosin heavy chain (MHC) solubility at
pH 6 - 10. Changes in total sulfhydryl (SH) content and surface hydrophobicity (S [subscript o])
were associated with the different molecular weight distributions of the soluble proteins. At pH 4 and IS 10-100 mM, MHC was soluble but degraded. At pH 10,
the formation of high MW polymers was observed at IS [greater than or equal to] 150 mM.
Gels obtained from FPI prepared at pHl1/IS150 and conventional surimi (CS)
were superior to FPI prepared at pH 3 and/or other IS levels. There was no correlation
between protein solubility and gel properties of FPI. Gelation mechanisms of acid and
alkali-treated FPI were identical under the same IS condition. FPI prepared at pH
3 or 11 could be partly refolded at pH 7.
No significant difference in texture was observed between alkali-treated
protein isolates (AKPI, pH 11) kept frozen at pH 5.5 and 7.0. Strongest gel was found
for AKPI with cryoprotectants (C) and without freeze/thaw (FT) cycles at both pH
storage (5C & 7C), while poor gel was obtained from AKPI without cryoprotectants
(NC) and with FT (5NC-F & 7NC-F). 5NC-F & 7NC-F demonstrated the lowest S [subscript o]
and total SH probably suggesting that proteins were more aggregated as a result of
hydrophobic interactions and disulfide bonds.
Scanning electron microscope (SEM) revealed the most discontinuity of gels
from AKPI without cryoprotectants and with FT and showed less protein stability
when stored at pH 5.5 than at neutral pH. Raman spectral analysis demonstrated that
refolding of AKPI by pH adjustment to 7.0 was achieved, but not identical to the
native protein. CS contained higher α-helix content (~50%) than AKPI (~20-30%).
Frozen storage induced a decrease and an increase in the α-helix of CS and AKPI
samples, respectively. Alkali-treated proteins were slightly less stable than CS during
frozen storage.Graduation date: 2005
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Santos, João Pedro Ferreira dos. "Effect of high-pressure pre-treatment on the enzymatic activity related to quality loss in frozen hake." Master's thesis, 2018. http://hdl.handle.net/10773/25529.
Full textAbstract:
Consumers demand for high quality food stuffs with no preservatives and with extended shelf-life, retaining the quality properties, led to the development of new processing technologies. One of those technologies, studied in this work, is High Pressure Processing (HPP), which has shown good results on fish shelf-life extension, with great importance in fish safety by inactivation of microbial load (mostly pathogenic microorganisms) in refrigerated fish, and inactivation of certain degradative enzymes, mainly in frozen fish.
Fish products are usually stored under refrigeration or frozen to maintain their quality and safety patterns. However, there are still several reactions that cause fish degradation. For instance, even under frozen storage, enzymatic activity still occurs. According to the literature, HPP has shown to be a promising pre-treatment to inhibit these enzymes and extend frozen fish-shelf-life.
This work aimed to determine the effect of HPP (150 MPa for 2 minutes) and storage temperature (-10, -20 and -30 ºC) on the quality of frozen hake muscle (Merluccius merluccius). It was verified that HPP resulted in a decrease of calpains activity (59 %) after 12 months of storage at -20 ºC and maintained the activity of acid phosphatase, cathepsin B and calpains after 12 months at -30 ºC Furthermore, the quantification of sulfhydryl (SH) groups indicated that the HP treatment results in higher SH content (increase up to 190%), as well as increased storage time (increase up to 120%), being this increase probably related with protein denaturation of fish muscle.
This work presents relevant information concerning the employment of HP pre-treatments to reduce enzymatic activity associated to quality loss in frozen European hake (Merluccius merluccius). This type of processing can so be of interest to enhance the quality preservation of frozen hake, as well as of other species.A exigência dos consumidores por produtos alimentares de elevada qualidade sem conservantes e com tempo de prateleira alargado, mantendo a sua qualidade, levou ao desenvolvimento de novas tecnologias para o seu processamento. Uma dessas tecnologias, abordada neste trabalho, é o Processamento por Alta Pressão (HPP), que tem apresentado bons resultados na extensão do tempo de prateleira em peixe, com especial importância para a segurança dos produtos, ao reduzir a carga microbiana (maioritariamente patogénicos) em peixe refrigerado e inibir a atividade de certas enzimas degradativas, principalmente em peixe congelado. Os produtos da pesca são normalmente armazenados em refrigeração ou congelados, de modo a manter os seus padrões de qualidade e segurança. No entanto, há diversas reações que ainda assim causam a degradação do peixe. Por exemplo, mesmo enquanto congelado, o peixe sofre alterações devido à atividade enzimática. De acordo com a literatura, o HPP mostrou grande potencial na inativação dessas enzimas e, consequentemente, na extensão do tempo de prateleira do peixe. Este trabalho visou determinar o efeito de um pré-tratamento por alta pressão (150 MPa por 2 minutos) e temperatura de armazenamento (-10, -20 e -30 ºC) na atividade enzimática do músculo de pescada congelada (Merluccius merluccius). Verificou–se que o pré-tratamento de HP possibilitou a diminuição de atividade das calpaínas (59 %) após 12 meses a -20 ºC e a manutenção das atividades da fosfatase ácida, catepsina B e calpaínas após 12 meses a -30 ºC. Verificou-se ainda um aumento no conteúdo em grupos tiol (SH) com o pré-tratamento (até 190%) e ao longo do tempo de armazenamento (até 120%), estando esse aumento possivelmente relacionado com a desnaturação proteica do músculo de peixe. Este trabalho apresenta assim informação importante relativa à aplicação de pré-tratamentos por alta pressão para reduzir a atividade enzimática associada a deterioração da pescada congelada (Merluccius merluccius). Este tipo de processamento pode assim ser relevante para uma melhor preservação da qualidade da pescada congelada, bem como possivelmente de outras espécies
Mestrado em Biotecnologia
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Silva, Paulo Miguel Guimarães da. "Contributions to Personal Data Protection and Privacy Preservation in Cloud Environments." Doctoral thesis, 2021. http://hdl.handle.net/10316/95291.
Full textAbstract:
Tese no âmbito do Programa de Doutoramento em Ciências e Tecnologias da Informação, apresentada ao Departamento de Engenharia Informática da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.Personal data is currently being used in countless applications in a vast number of areas. Despite national and international legislation, the fact is that individuals still have little to no control over who uses their data and for what purposes. As regulations vary from region to region, data is often stored and processed in multiple locations by multiple data processors. Moreover, the security concerns of a system are sometimes addressed individually or in an ad-hoc manner, which may result in inadequate solutions. In the end, data protection and privacy assurances are still, in many cases, only a theoretical possibility. As such, it is necessary to propose mechanisms that maximise data protection and provide increased privacy assurances. A strategy to ensure appropriate levels of security and privacy is mandatory. In this work, it was possible to design, develop and evaluate mechanisms that fill the issues mentioned above. One of the pillars of this strategy is the inclusion of Authentication, Authorisation and Accounting (AAA) solutions that securely control access to individuals' data. The other pillar relies on the usage of intelligent, automated, and non-intrusive mechanisms that monitor and control personal data to increase privacy assurances. To fulfil such strategy, the development of a cloud-based AAA solution was the very first step to control individuals' access to data. The proposed solution is composed of a reverse proxy, a custom web application and a NoSQL database. The mechanisms proposed in this thesis recur to Natural Language Processing (NLP), Named Entity Recognition (NER) and Machine Learning (ML) algorithms in a hybrid approach. A series of NER models capable of identifying personal information are also trained with algorithms such as Multi-Layer Perceptron (MLP) and Random Forests (RF), using only publicly available datasets as a source of training and validation data. The mechanisms proposed in this work comply with existing regulations and are designed under appropriate cloud-based deployment and life cycle management strategies. Moreover, this thesis proposes a fuzzy privacy risk model that allows the assessment of privacy risk levels associated with data transactions. The advantages and drawbacks of the proposed mechanisms were evaluated in pilot use cases in the scope of two international projects: H2020 EUBra-BIGSEA and H2020 PoSeID-on. The evaluation conducted on both technical and user-centred scenarios indicates that the proposed mechanisms have high data classifying accuracy, support large volumes of data with distinct characteristics and to increase individuals' privacy awareness and control.
Os dados pessoais são atualmente utilizados em inúmeras aplicações num grande número de áreas. Apesar da legislação nacional e internacional, o facto é que indivíduos ainda têm pouco ou nenhum controlo sobre quem usa os seus dados pessoais, e para que fins. Como os regulamentos variam de região para região, os dados geralmente são armazenados e processados em vários locais, e por vários processadores de dados. Além disso, as questões de segurança dos sistemas por vezes são tratadas individualmente ou de maneira ad-hoc, o que pode resultar em soluções inadequadas. No final, a proteção de dados e as garantias de privacidade ainda são, em muitos casos, apenas uma possibilidade teórica. Como tal, é necessário propor mecanismos que maximizem a proteção de dados e forneçam maiores garantias de privacidade. Uma estratégia para garantir níveis adequados de segurança e privacidade é obrigatória. Neste trabalho, foi possível projetar, desenvolver e avaliar mecanismos que atendem às questões mencionadas acima. Um dos pilares desta estratégia é a inclusão de soluções de Autenticação, Autorização e Auditabilidade (AAA) que controlam o acesso aos dados pessoais com segurança. O outro pilar depende do uso de mecanismos inteligentes, automatizados e não intrusivos que monitoram e controlam os dados pessoais de modo a aumentar as garantias de privacidade. Para seguir essa estratégia, o primeiro passo foi o desenvolvimento de uma solução AAA baseada na nuvem, que controla o acesso a dados pessoais. A solução proposta é composta por um procurador reverso, uma aplicação web personalizada e uma base de dados NoSQL. Os mecanismos propostos nesta tese recorrem a Processamento de Linguagem Natural (PNL), Reconhecimento de Entidades Mencionadas (REM) e Aprendizagem Automática (AA) de uma forma híbrida. Uma série de modelos REM capazes de identificar informações pessoais também são treinados com algoritmos tais como Perceptron Multicamada (PM) e Florestas de Decisão Aleatórias (FDA), usando apenas conjuntos de dados publicamente disponíveis, como fonte de dados de treino e validação. Os mecanismos propostos neste trabalho estão em conformidade com os regulamentos existentes e são projetados de acordo com uma implementação baseada em nuvem e estratégias de gestão de ciclo de vida apropriadas. Além disso, esta tese propõe um modelo fuzzy de risco de privacidade que permite avaliar os níveis de risco de privacidade associados às transações de dados. As vantagens e desvantagens dos mecanismos propostos foram avaliadas em casos de uso piloto no âmbito de dois projetos internacionais: H2020 EUBra-BIGSEA e H2020 PoSeID-on. A avaliação realizada em cenários técnicos e centrados no usuário indica que os mecanismos propostos têm alta precisão de classificação de dados, suportam grandes volumes de dados com características distintas e aumentam a perceção e o controle da privacidade dos indivíduos.
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Sikwese, Fred Edington. "Sorghum phenolic extracts : their storage stability and antioxidant activity in sunflower oil." Diss., 2006. http://hdl.handle.net/2263/26488.
Full textAbstract:
Whole grain and bran samples of two Malawian sorghums, Phatafuli, (a brown-coloured condensed tannin variety) and Shabalala, (a white-coloured condensed tannin-free variety) were analysed for their content of total phenols, condensed tannins and antioxidant activities. The effect of oxidizing conditions during extraction, and the storage stability of a freeze-dried crude phenolic extract (CPE) from the condensed tannin sorghum bran as influenced by packaging, storage temperature and length of storage, in relation to its content of total phenols, condensed tannins and antioxidant activity was also investigated. Antioxidant activity of the CPE, in comparison with tertiary butyl hydroquinone (TBHQ), was then evaluated in sunflower oil at concentrations of 1000, 1500 and 2000 ppm in the absence or presence of ferric ions at 2.2 and 4.4 ppm in the dark at 65oC.Progression of oxidation was monitored by measurement of peroxide values (PV) and anisidine values (AV) during a 14-day storage period. Phatafuli contained higher content of total phenols and antioxidant activity than Shabalala both in the whole grain and the bran, probably due to the presence of condensed tannins in Phatafuli sorghum, which were not detected in Shabalala sorghum. For both sorghum varieties, the bran contained higher levels of total phenols and antioxidant activity than the whole grain, confirming that phenolic compounds in sorghum are largely concentrated in the bran. Antioxidant activities of the sorghum varieties correlated highly with their total phenol and condensed tannin contents, suggesting that the phenolic compounds were largely responsible for the antioxidant activities of the sorghum grains. Bubbling of oxygen into the liquid crude phenolic extract did not have any significant effect on the parameters tested. Similarly, vacuum-packed samples did not differ significantly in the parameters tested from the samples that were not vacuum-packed. CPE samples stored at –20oC had significantly higher levels of total phenols, condensed tannins and antioxidant activity than those stored at 25oC during some days of storage. Storage time was however the major factor influencing the levels of total phenols, condensed tannins and antioxidant activity of the CPE from Phatafuli sorghum during storage, which suggested that CPE from condensed tannin sorghum bran might need to be used shortly after extraction to ensure optimum antioxidant activity. There was an insignificant correlation between the antioxidant activities of the CPE and their phenolic contents during storage, which could have been due to the formation of new compounds with a lower antioxidant capacity. The CPE inhibited oxidation of sunflower oil as shown by lower peroxide values and anisidine values compared to control samples. The CPE was however less effective in reducing peroxide values compared to TBHQ, but was similar to TBHQ in reducing anisidine values. In the presence of ferric ions, the CPE appeared to be less effective in reducing peroxide values compared to TBHQ, but appeared to be more effective than TBHQ in reducing anisidine values. The results showed that the tannin sorghum bran CPE appeared to act as both lipid radical scavengers and metal chelators. The CPE however imparted colour to the sunflower oil, which could limit its application as a natural antioxidant in edible oils.Dissertation (MSc(Agric) Food Science and Technology)--University of Pretoria, 2008.
Food Science
unrestricted
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(7451486), Gabriella Mendes Candido De Oliveira. "Modeling Microbial Inactivation Subjected to Nonisothermal and Non-thermal Food Processing Technologies." Thesis, 2019.
Find full textAbstract:
Modeling microbial inactivation has a great influence on the optimization, control and design of food processes. In the area of food safety, modeling is a valuable tool for characterizing survival curves and for supporting food safety decisions. The modeling of microbial behavior is based on the premise that the response of the microbial population to the environment factors is reproducible. And that from the past, it is possible to predict how these microorganisms would respond in other similar environments. Thus, the use of mathematical models has become an attractive and relevant tool in the food industry.
This research provides tools to relate the inactivation of microorganisms of public health importance with processing conditions used in nonisothermal and non-thermal food processing technologies. Current models employ simple approaches that do not capture the realistic behavior of microbial inactivation. This oversight brings a number of fundamental and practical issues, such as excessive or insufficient processing, which can result in quality problems (when foods are over-processed) or safety problems (when foods are under-processed). Given these issues, there is an urgent need to develop reliable models that accurately describe the inactivation of dangerous microbial cells under more realistic processing conditions and that take into account the variability on microbial population, for instance their resistance to lethal agents. To address this urgency, this dissertation focused on mathematical models, combined mathematical tools with microbiological science to develop models that, by resembling realistic and practical processing conditions, can provide a better estimation of the efficacy of food processes. The objective of the approach is to relate the processing conditions to microbial inactivation. The development of the modeling approach went through all the phases of a modeling cycle from planning, data collection, formulation of the model approach according to the data analysis, and validation of the model under different conditions than those that the approach was developed.
A non-linear ordinary differential equation was used to describe the inactivation curves with the hypothesis that the momentary inactivation rate is not constant and depends on the instantaneous processing conditions. The inactivation rate was related to key process parameters to describe the inactivation kinetics under more realistic processing conditions. From the solution of the non-linear ordinary differential equation and the optimization algorithm, safety inferences in the microbial response can be retrieved, such as the critical lethal variable that increases microbial inactivation. For example, for nonisothermal processes such as microwave heating, time-temperature profiles were modeled and incorporated into the inactivation rate equation. The critical temperature required to increase the microbial inactivation was obtained from the optimization analysis. For non-thermal processes, such as cold plasma, the time-varying concentration of reactive gas species was incorporated into the inactivation rate equation. The approach allowed the estimation of the critical gas concentration above which microbial inactivation becomes effective. For Pulsed Electric Fields (PEF), the energy density is the integral parameter that groups the wide range of parameters of the PEF process, such as the electric field strength, the treatment time and the electrical conductivity of the sample. The literature has shown that all of these parameters impact microbial inactivation. It has been hyphothesized that the inactivation rate is a function of the energy density and that above a threshold value significant microbial inactivation begins.
The differential equation was solved numerically using the Runge-Kutta method (ode45 in MATLAB ®). The lsqcurvefit function in MATLAB ® estimated the kinetic parameters. The approach to model microbial inactivation, whether when samples were subjected to nonisothermal or to non-thermal food processes, was validated using data published in the literature and/or in other samples and treatment conditions. The modeling approaches developed by this dissertation are expected to assist the food industry in the development and validation process to achieve the level of microbial reduction required by regulatory agencies. In addition, it is expected to assist the food industry in managing food safety systems through support food safety decision-making, such as the designation of the minimal critical parameter that may increase microbial inactivation. Finally, this dissertation will contribute in depth to the field of food safety and engineering, with the ultimate outcome of having a broad and highly positive impact on human health by ensuring the consumption of safe food products.