Dissertations / Theses on the topic 'No Reference Quality Assessment'

How to assess the quality of a genome assembly without the help of a reference sequence is an open question. Only a few techniques are currently used in the literature and each has obvious bias. An additional method, restriction enzyme associated DNA (RAD) marker alignment, is proposed here. With high enough density, this method should be able to assess the quality of de novo assemblies without the biases of current methods. With the growing ambition to sequence new genomes and the accelerating ability to do so cost effectively, methods to assess the quality of reference-free genome assemblies will become increasingly important. In addition to the existing methods of EST and conserved sequence alignment, RAD marker alignment may contribute to this effort.

This thesis focuses on No Reference (NR) methods for Image Quality Assessment (IQA). A review of the IQA field is presented in Chapter 2; where the different IQA methods are described and classified. In particular, the application of IQA methods within a workflow chain is discussed. In Chapter 3 we focus on NR metrics for JPEG-blockiness and noise artifacts. It is in general assumed that subjective methods produce an actual estimate of the perceived quality while objective methods produce values that should be correlated with human perceptions as best as possible. From the analysis of the regression curves that correlate objective and subjective data we have found that in some cases the metric's predictions are not in correspondence with the subjective scores. After reviewing the available databases, we realize that the distortion ranges considered are not in general representative of real case applications. Therefore, in Chapter 4 the Imaging and Vision Lab (IVL) database is introduced. It was generated with the aim of assessing the quality of images corrupted by JPEG and noise. In Chapter 5 we approach the NR-IQA field by focusing on a classification problem. A framework based on machine learning classification is proposed that let us evaluate how images can be classified within different groups or classes, according to their quality. NR metrics are considered as features and the assigned classes are obtained from the psychovisual data. For the JPEG distortion case, the feature space of the classifiers is built using each NR metric as single feature and also a pool of eleven NR metrics. Classification within five and three classes was addressed. In the former case, the five classes are in correspondence to the five categories recommended by the ITU (excellent, good, fair, poor, and bad) when designing image quality experiments. In the latter case we were interested in classifying images as high, medium or low quality ones. The classifiers are trained and tested on different databases. The classifier obtained using the pool of metrics outperforms each single metric classifier. Better performance is obtained in the case of three classes. Considering an image as the combining of two signals, content and distortion, we note that the crosstalk between both signals influences both subjective and objective quality assessment. We address this problem in Chapter 6 where our working hypothesis is that regression can be improved if performed within a group of images that present similar contents in terms of low level features. The criteria chosen to divide the images in different groups is the image complexity. The proposed strategy consists on two steps: the images (of a given database) are first classified in three groups of low, medium and high complexity. In a second step, regression is performed within each of these groups separately. The strategy is tested for different NR metrics for JPEG-blockiness and noise artifacts, different databases are considered. Correlation coefficients are computed and statistical significance tests are applied. The gain in performance depends on the metric and distortion considered. Summarizing, the two main proposals of this research work, i.e. the classification approach that combines several NR metrics and the grouping strategy, are able to outperform the correlation between subjective and objective data for the case of JPEG-blockiness. Both strategies can be extended to consider other type of distortions.

The overwhelming trend of the usage of multimedia services has raised the consumers' awareness about quality. Both service providers and consumers are interested in the delivered level of perceptual quality. The perceptual quality of an original video signal can get degraded due to compression and due to its transmission over a lossy network. Video quality assessment (VQA) has to be performed in order to gauge the level of video quality. Generally, it can be performed by following subjective methods, where a panel of humans judges the quality of video, or by using objective methods, where a computational model yields an estimate of the quality. Objective methods and specifically No-Reference (NR) or Reduced-Reference (RR) methods are preferable because they are practical for implementation in real-time scenarios. This doctoral thesis begins with a review of existing approaches proposed in the area of NR image and video quality assessment. In the review, recently proposed methods of visual quality assessment are classified into three categories. This is followed by the chapters related to the description of studies on the development of NR and RR methods as well as on conducting subjective experiments of VQA. In the case of NR methods, the required features are extracted from the coded bitstream of a video, and in the case of RR methods additional pixel-based information is used. Specifically, NR methods are developed with the help of suitable techniques of regression using artificial neural networks and least-squares support vector machines. Subsequently, in a later study, linear regression techniques are used to elaborate the interpretability of NR and RR models with respect to the selection of perceptually significant features. The presented studies on subjective experiments are performed using laboratory based and crowdsourcing platforms. In the laboratory based experiments, the focus has been on using standardized methods in order to generate datasets that can be used to validate objective methods of VQA. The subjective experiments performed through crowdsourcing relate to the investigation of non-standard methods in order to determine perceptual preference of various adaptation scenarios in the context of adaptive streaming of high-definition videos. Lastly, the use of adaptive gain equalizer in the modulation frequency domain for speech enhancement has been examined. To this end, two methods of demodulating speech signals namely spectral center of gravity carrier estimation and convex optimization have been studied.

Images are playing a more and more important role in sharing, expressing, mining and exchanging information in our daily lives. Now we can all easily capture and share images anywhere and anytime. Since digital images are subject to a wide variety of distortions during acquisition, processing, compression, storage, transmission and reproduction; it becomes necessary to assess the Image Quality. In this thesis, starting from an organized overview of available Image Quality Assessment methods, some original contributions in the framework of No-reference image quality metrics are described.

There is a demand for video quality measurements in modern video applications specifically in wireless and mobile communication. In real time video streaming it is experienced that the quality of video becomes low due to different factors such as encoder and transmission errors. HEVC/H.265 is considered as one of the promising codecs for compression of ultra-high definition videos. In this research, full reference based video quality assessment is performed. The raw format reference videos have been taken from Texas database to make test videos data set. The videos are encoded using HM9 reference software in HEVC format. Encoding errors has been set during the encoding process by adjusting the QP values. To introduce packet loss in the video, the real-time environment has been created. Videos are sent from one system to another system over UDP protocol in NETCAT software. Packet loss is induced with different packet loss ratios into the video using NETEM software. After the compilation of video data set, to assess the video quality two kind of analysis has been performed on them. Subjective analysis has been carried on different human subjects. Objective analysis has been achieved by applying five quality matrices PSNR, SSIM, UIQI, VFI and VSNR. The comparison is conducted on the objective measurement scores with the subjective and in the end results deduce from classical correlation methods.

This study examined the quality of English language programmes at Libyan universities and in particular at Tripoli University, in order to identify the factors that have contributed to the decline in standards of students studying English at degree level. The motivation behind selecting this topic area is that English language programme at Tripoli University is dated and not fit for purpose. Thus English programmes are in need of major changes to improve students’ language skills. There is a broad literature on the need for research on language programme evaluation across many parts of the world. Many educational systems and teaching institutions undertake periodic evaluation of their programmes. Many key authors agree on the importance of evaluation and argue that evaluation is more than just the collection of information and data, it involves making judgements about the worth, merit or value of a programme. Programme evaluation is also a form of validation process to find out if the assessed programme is fit for purpose and meets the students’ needs and expectations. This study adopted a mixed methods approach as relying on one single research approach and strategy would reduce the effectiveness of this study. The rationale for adopting a quantitative and qualitative research approach is related to the purpose of the study, the nature of the problem and research questions. Thus quantitative data were collected through questionnaires involving (300) students at Tripoli University (Libya) and was analysed using SPSS. This was supported by qualitative data using semi-structured interviews involving eight lecturers at Tripoli University using content analysis. The findings revealed that most of the students recognise the need for radical changes to revamp the language programme to address the decline of English language skills. Students are aware of their inadequate English standards, as the findings showed that a majority of students had positive attitudes and were highly motivated to learn the English language. The conclusions indicated that the English language programme has major shortcomings that need to be addressed such as resources, teaching and learning facilities, training workshops for staff development and insufficient library resources. The results also clarified that the English language programme needs to be evaluated on a regular basis in order to assess its effectiveness in order to enhance the quality of education. The study makes suggestions that will have implications for improvement and development for the English language programme. A framework is proposed to reform and revamp the English language programme. This study contributes to raise awareness regarding the importance of evaluating English language programmes, to allow decision-makers to take necessary steps to promote the English language. This study also makes a theoretical contribution by expanding the literature on the research topic which is Quality assessment English language programmes at Libyan Universities. It also raises awareness about the root causes of the decline of English language standards.

Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2017.
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Um dos principais fatores para a redução da qualidade do conteúdo visual, em sistemas de imagem digital, são a presença de degradações introduzidas durante as etapas de processamento de sinais. Contudo, medir a qualidade de um vídeo implica em comparar direta ou indiretamente um vídeo de teste com o seu vídeo de referência. Na maioria das aplicações, os seres humanos são o meio mais confiável de estimar a qualidade de um vídeo. Embora mais confiáveis, estes métodos consomem tempo e são difíceis de incorporar em um serviço de controle de qualidade automatizado. Como alternativa, as métricas objectivas, ou seja, algoritmos, são geralmente usadas para estimar a qualidade de um vídeo automaticamente. Para desenvolver uma métrica objetiva é importante entender como as características perceptuais de um conjunto de artefatos estão relacionadas com suas forças físicas e com o incômodo percebido. Então, nós estudamos as características de diferentes tipos de artefatos comumente encontrados em vídeos comprimidos (ou seja, blocado, borrado e perda-de-pacotes) por meio de experimentos psicofísicos para medir independentemente a força e o incômodo desses artefatos, quando sozinhos ou combinados no vídeo. Nós analisamos os dados obtidos desses experimentos e propomos vários modelos de qualidade baseados nas combinações das forças perceptuais de artefatos individuais e suas interações. Inspirados pelos resultados experimentos, nós propomos uma métrica sem-referência baseada em características extraídas dos vídeos (por exemplo, informações DCT, a média da diferença absoluta entre blocos de uma imagem, variação da intensidade entre pixels vizinhos e atenção visual). Um modelo de regressão não-linear baseado em vetores de suporte (Support Vector Regression) é usado para combinar todas as características e estimar a qualidade do vídeo. Nossa métrica teve um desempenho muito melhor que as métricas de artefatos testadas e para algumas métricas com-referência (full-reference).
The main causes for the reducing of visual quality in digital imaging systems are the unwanted presence of degradations introduced during processing and transmission steps. However, measuring the quality of a video implies in a direct or indirect comparison between test video and reference video. In most applications, psycho-physical experiments with human subjects are the most reliable means of determining the quality of a video. Although more reliable, these methods are time consuming and difficult to incorporate into an automated quality control service. As an alternative, objective metrics, i.e. algorithms, are generally used to estimate video quality quality automatically. To develop an objective metric, it is important understand how the perceptual characteristics of a set of artifacts are related to their physical strengths and to the perceived annoyance. Then, to study the characteristics of different types of artifacts commonly found in compressed videos (i.e. blockiness, blurriness, and packet-loss) we performed six psychophysical experiments to independently measure the strength and overall annoyance of these artifact signals when presented alone or in combination. We analyzed the data from these experiments and proposed several models for the overall annoyance based on combinations of the perceptual strengths of the individual artifact signals and their interactions. Inspired by experimental results, we proposed a no-reference video quality metric based in several features extracted from the videos (e.g. DCT information, cross-correlation of sub-sampled images, average absolute differences between block image pixels, intensity variation between neighbouring pixels, and visual attention). A non-linear regression model using a support vector (SVR) technique is used to combine all features to obtain an overall quality estimate. Our metric performed better than the tested artifact metrics and for some full-reference metrics.

As there is a rapid growth in the field of wireless communications, the demand for various multimedia services is also increasing. The data that is being transmitted suffers from distortions through source encoding and transmission over errorprone channels. Due to these errors, the quality of the content is degraded. There is a need for service providers to provide certain Quality of Experience (QoE) to the end user. Several methods are being developed by network providers for better QoE.The human tendency mainly focuses on distortions in the Region of Interest(ROI) which are perceived to be more annoying compared to the Background(BG). With this as a base, the main aim of this thesis is to get an accurate prediction quality metric to measure the quality of the image over ROI and the BG independently. Reduced Reference Image Quality Assessment (RRIQA), a reduced reference image quality assessment metric, is chosen for this purpose. In this method, only partial information about the reference image is available to assess the quality. The quality metric is measured independently over ROI and BG. Finally the metric estimated over ROI and BG are pooled together to get aROI aware metric to predict the Mean Opinion Score (MOS) of the image.In this thesis, an ROI aware quality metric is used to measure the quality of distorted images that are generated using a wireless channel. The MOS of distorted images are obtained. Finally, the obtained MOS are validated with the MOS obtained from a database [1].It is observed that the proposed image quality assessment method provides better results compared to the traditional approach. It also gives a better performance over a wide variety of distortions. The obtained results show that the impairments in ROI are perceived to be more annoying when compared to the BG.

Le domaine de recherche dans l'évaluation objective de la qualité des images couleur a connu un regain d'intérêt ces dernières années. Les travaux sont essentiellement dictés par l'avènement des images numérique et par les nouveaux besoins en codage d'images (compression, transmission, restauration, indexation,…). Jusqu'à présent la meilleure évaluation reste visuelle (donc subjective) soit par des techniques psychophysiques soit par évaluation experte. Donc, il est utile, voire nécessaire, de mettre en place des critères et des mesures objectifs qui produisent automatiquement des notes de qualité se rapprochant le plus possible des notes de qualité données par l'évaluation subjective. Nous proposons, tout d'abort, une nouvelle métrique avec référence d'évaluation de la qualité des images couleur, nommée Delta E globale, se base sur l'aspect couleur et intègre les caractéristiques du système visuel humain (SVH). Les performances ont été mesurées dans deux domaines d'application la compression et la restauration. Les expérimentations réalisées montrent une corrélation importante entre les résultats obtenus et l'appréciation subjective. Ensuite, nous proposons une nouvelle approche d'évaluation sans référence de la qualité des images couleur en se basant sur les réseaux de neurones : compte tenu du caractère multidimensionnel de la qualité d'images, une quantification de la qualité a été proposée en se basant sur un ensemble d'attributs formant le descripteur PN (Précision, Naturalité). La précision traduit la netteté et la clarté. Quant à la naturalité, elle traduit la luminosité et la couleur. Pour modéliser le critère de la couleur, trois métriques sans référence ont été définies afin de détecter la couleur dominante dans l'image, la proportion de cette couleur et sa dispersion spatiale. Cette approche se base sur les réseaux de neurones afin d'imiter la perception du SVH. Deux variantes de cette approche ont été expérimentées (directe et progressive). Les résultats obtenus ont montré la performance de la variante progressive par rapport à la variante directe. L'application de l'approche proposée dans deux domaines : dans le contexte de la restauration, cette approche a servi comme un critère d'arrêt automatique pour les algorithmes de restauration. De plus, nous l'avons utilisé au sein d'un système d'estimation de la qualité d'images afin de détecter automatiquement le type de dégradation contenu dans une image. Dans le contexte de l'indexation et de la recherche d'images, l'approche proposée a servi d'introduire la qualité des images de la base comme index. Les résultats expérimentaux ont montré l'amélioration des performances du système de recherche d'images par le contenu en utilisant l'index qualité ou en réalisant un raffinement des résultats avec le critère de qualité
The research area in the objective quality assessment of the color images has been a renewed interest in recent years. The work is primarily driven by the advent of digital pictures and additional needs in image coding (compression, transmission, recovery, indexing,...). So far the best evaluation is visual (hence subjective) or by psychophysical techniques or by expert evaluation. Therefore, it is useful, even necessary, to establish criteria and objectives that automatically measures quality scores closest possible quality scores given by the subjective evaluation. We propose, firstly, a new full reference metric to assess the quality of color images, called overall Delta E, based on color appearance and incorporates the features of the human visual system (HVS). Performance was measured in two areas of application compression and restoration. The experiments carried out show a significant correlation between the results and subjective assessment.Then, we propose a new no reference quality assessmenent color images approach based on neural networks: given the multidimensional nature of image quality, a quantification of quality has been proposed, based on a set of attributes forming the descriptor UN (Utility, Naturalness). Accuracy reflects the sharpness and clarity. As for naturality, it reflects the brightness and color. To model the criterion of color, three no reference metrics were defined to detect the dominant color in the image, the proportion of that color and its spatial dispersion. This approach is based on neural networks to mimic the HVS perception. Two variants of this approach have been tried (direct and progressive). The results showed the performance of the progressive variant compared to the direct variant. The application of the proposed approach in two areas: in the context of restoration, this approach has served as a stopping criterion for automatic restoration algorithms. In addition, we have used in a system for estimating the quality of images to automatically detect the type of content in an image degradation. In the context of indexing and image retrieval, the proposed approach was used to introduce the quality of images in the database as an index. The experimental results showed the improvement of system performance image search by content by using the index or by making a quality refinement results with the quality criterion

Les objectifs de ce travail de thèse ont été: d’une part de détecter automatique-ment les images gelées dans des vidéos télédiffusées; et d’autre part de mesurer sans référencela qualité des vidéos télédiffusées (IP et DVB-T). Ces travaux ont été effectués dans le cadred’un projet de recherche mené conjointement par le LaBRI et la société Audemat WorldCastSystems.Pour la détection d’images gelées, trois méthodes ont été proposées: MV (basée vecteurde mouvement), DC (basée sur les coefficients DC de la DCT) et SURF (basée sur les pointscaractéristiques SURF). Les deux premières méthodes ne nécessitent qu’un décodage partieldu flux vidéo.Le second objectif était de mesurer sans référence la qualité des vidéos télédiffusées (IP etDVB-T). Une métrique a été développée pour mesurer la qualité perçue lorsque le flux vidéoa été altéré par des pertes de transmission. Cette métrique "Weighted Macro-Block ErrorRate" (WMBER) est fondée sur la mesure de la saillance visuelle et la détection des macro-blocs endommagés. Le rôle de la saillance visuelle est de pondérer l’importance des erreursdétectées. Certaines améliorations ont été apportées à la construction des cartes de saillancespatio-temporelle. En particulier, la fusion des cartes de saillance spatiale et temporelle aété améliorée par rapport à l’état de l’art. Par ailleurs, plusieurs études ont montré que lasémantique d’une scène visuelle avait une influence sur le comportement du système visuelhumain. Il apparaît que ce sont surtout les visages humains qui attirent le regard. C’est laraison pour laquelle nous avons ajouté une dimension sémantique aux cartes de saillancespatio-temporelle. Cette dimension sémantique est essentiellement basée sur le détecteurde visage de Viola Jones. Pour prédire la qualité perçue par les utilisateurs, nous avonsutilisé une méthode par apprentissage supervisé. Cette méthode offre ainsi la possibilité deprédire la métrique subjective "Mean Opinion Score" (MOS) à partir de mesures objectivestelles que le WMBER, PSNR ou SSIM. Une expérience psycho-visuelle a été menée avec 50sujets pour évaluer ces travaux. Cette base de données vidéo Haute-Définition est en coursde transfert à l’action COST Qualinet. Ces travaux ont également été évalués sur une autrebase de données vidéo (en définition standard) provenant de l’IRCCyN
The goal of this Ph.D thesis is to design a no-reference video quality assessment method for lossy net-works. This Ph.D thesis is conducted in collaboration with the Audemat Worldcast Systemscompany.Our first no-reference video quality assessment indicator is the frozen frame detection.Frozen frame detection was a research topic which was well studied in the past decades.However, the challenge is to embed a frozen frame detection method in the GoldenEagleAudemat equipment. This equipment has low computation resources that not allow real-time HD video decoding. Two methods are proposed: one based on the compressed videostream motion vectors (MV-method) and another one based on the DC coefficients from thedct transform (DC-method). Both methods only require the partial decoding of the com-pressed video stream which allows for real-time analysis on the GoldenEagle equipment.The evaluation shows that results are better than the frame difference base-line method.Nevertheless, the MV and the DC methods are only suitable with for MPEG2 and H.264video streams. So a third method based on SURF points is proposed.As a second step on the way to a no-reference video quality assessment metric, we areinterested in the visual perception of transmission impairments. We propose a full-referencemetric based on saliency maps. This metric, Weighted Mean Squared Error (WMSE), is theMSE metric weighted by the saliency map. The saliency map role is to distinguish betweennoticeable and unnoticeable transmission impairments. Therefore this spatio-temporal saliencymaps is computed on the impaired frame. Thus the pixel difference in the MSE computationis emphasized or diminished with regard to the pixel saliency. According to the state of theart, several improvements are brought to the saliency map computation process. Especially,new spatio-temporal saliency map fusion strategies are designed.After our successful attempt to assess the video quality with saliency maps, we develop ano-reference quality metric. This metric, Weighted Macro-Block Error Rate (WMBER), relies on the saliency map and the macro-block error detection. The macro-block error detectionprovides the impaired macro-blocks location in the frame. However, the impaired macro-blocks are concealed with more or less success during the decoding process. So the saliencymap provides the user perceived impairment strength for each macro-block.Several psycho-visual studies have shown that semantics play an important role in visualscene perception. These studies conclude that faces and text are the most attractive. Toimprove the spatio-temporal saliency model a semantic dimension is added. This semanticsaliency is based on the Viola & Jones face detector.To predict the Mean Opinion Score (MOS) from objective metric values like WMBER,WMSE, PSNR or SSIM, we propose to use a supervised learning approach. This approach iscalled Similarity Weighted Average (SWA). Several improvements are brought to the originalSWA.For the metrics evaluation a psycho-visual experiment with 50 subjects has been carriedout. To measure the saliency map models accuracy, a psycho-visual experiment with aneye-tracker has also been carried out. These two experiments habe been conducted in col-laboration with the Ben Gurion University, Israel. WMBER and WMSE performances arecompared with reference metrics like SSIM and PSNR. The proposed metrics are also testedon a database provided by IRCCyN research laboratory

Doutoramento em Biologia
Diatoms are generally the most frequent and abundant algae in streams and are known by their responsiveness to changes in the environmental conditions of streams. Diatoms are frequently the only biological quality element representative of the aquatic flora in small streams. As a result, diatoms are nowadays a mandatory biological element in the evaluation of the ecological quality of European rivers, according to the Water Framework Directive. Nevertheless, there is still a relative lack of knowledge of key effects of global changes and spatial scale on diatoms. To bridge this gap, this work aims to study the effect of relevant global changes as well as spatial scale on diatom communities of temperate rivers and to deal with its implications in bioassessment. The relevant global changes were assessed in streams from the central Portuguese littoral region which is highly populated and suffers from high anthropogenic impacts. The effect of spatial scale on diatom communities was investigated by a laboratorial experiment (mesocosm experiment) and by using diatom data from temperate regions of the United States of America and Australia. In order to achieve the main aim, three global questions were raised: (1) How to deal with the historical anthropogenic influences in the bioassessment?; (2) Are extreme events due to climatic changes reflected in diatom communities? A comparison with macroinvertebrate communities; (3) How are diatom communities influenced at the spatial scale (small-scale: habitats; large-scale: inter-continental). A strong anthropogenic influence on the streams and rivers of the Portuguese littoral region was confirmed as well as the lack of true reference sites. Sites in the Least Disturbed Condition (LDC) had considerable high nutrient concentrations. As the strong anthropogenic pressures (e.g., alteration of the riparian vegetation, morphological condition and sediment load) prevented an adequate definition of reference conditions for streams in this area an alternative procedure to define suitable reference conditions was investigated, consisting of a combination of modelling and filter approach. This procedure is suitable to deal with the implications of global changes on diatom and on macroinvertebrate communities. The communities observed in the different streams were less homogeneous than those predicted for the same streams under reference conditions (i.e., through the filter approach), as would be expected in sites having variable levels of anthropogenic change. Along with the development of this new approach a new multimetric diatom index was developed. This index produced strong correlations with the selected pressures, providing a more comprehensive assessment of biological quality than the Indice de Polluosensibilité Spécifique (IPS) officially adopted for Portugal. To answer the second global question a smaller set of streams were used within the Portuguese littoral region that were affected by an unusual drought event that lead to the complete drying of the stream channels. Diatoms, as well as macroinvertebrates, were affected by the drought event considering trait proportions, community’s composition and bioassessment classifications. However, the diatom communities had a faster recovery response than macroinvertebrates. The type of substrate – hard and soft –representing the small spatial scale affected diatom communities by changing its composition and trait proportions but not water quality classification in a mesocosm experiment. However, the differences found in the epipsammic and epilithic diatom communities in the streams that were used to answer the first global question were more evident than those found in the mesocosm experiment. In fact, with the mesocosm results, and under the same physical and chemical conditions the IPS differences between substrates disappeared contrasting with the differences that were found in the streams. Additionally, the diatom communities were different between continents with the same type of climate, suggesting that diatom communities are also influenced at the large-scale (even at the order level). Therefore, constraints other than climate are likely to have contributed to the inter-continental differences in diatom community composition found at all taxonomical levels (e.g., geology, historical biogeographic processes and hydrology). On the whole, the results obtained during this study bring new information and new approaches to deal with the bioassessment. However, some more work must be done in order to investigate e.g., based in the global warming predictions, the effects of the temperature increase, on the water quality assessment based on diatom communities.
As diatomáceas são as algas que se encontram mais frequentemente e em maior abundância em cursos de água doce. São conhecidas pela capacidade dos diferentes taxa responderem a variações das condições ambientais dos rios e por serem frequentemente o único elemento de qualidade biológica representativo da flora aquática em pequenos rios e ribeiras. Em consequência destas características, e de acordo com a Directiva Quadro da Água, as diatomáceas são presentemente um dos elementos biológicos obrigatórios na avaliação da qualidade ecológica dos rios europeus. No entanto, ainda existe algum desconhecimento acerca dos efeitos das alterações globais e da escala espacial nas diatomáceas. Para colmatar esta lacuna, o presente trabalho tem como objetivo estudar o efeito de alterações globais relevantes e da escala espacial nas comunidades de diatomáceas de rios temperados assim como estudar a melhor forma de lidar com as suas implicações na biomonitorização. O efeito das alterações globais foi estudado em rios e ribeiras da região centro litoral de Portugal continental dado tratar-se de uma região densamente povoada e sujeita a impactos antropogénicos significativos. O efeito da escala espacial nas comunidades de diatomáceas foi investigado através de uma experiência laboratorial (mesocosmos) e também com recurso a informação estatística de comunidades de diatomáceas de várias regiões temperadas, incluindo as costas ocidentais dos Estados Unidos da América e da Austrália. De modo atingir o objetivo principal deste trabalho, três questões globais foram colocadas: (1) Como lidar com as influências antrópicas históricas na biomonitorização?; (2) Será que as comunidades de diatomáceas reflectem os eventos extremos causados pelas alterações climáticas? Uma comparação com as comunidades de macroinvertebrados; (3) Como são as comunidades de diatomáceas influenciadas pela escala espacial (pequena escala: habitats; grande escala: inter-continental). Verificou-se uma influência antropogénica considerável nos rios e ribeiras da região centro litoral de Portugal continental assim como a inexistência de verdadeiros locais de referência. Mesmo os locais considerados como estando em condições de menor perturbação apresentaram concentrações de nutrientes consideravelmente elevadas na água. Uma vez que as fortes pressões antropogénica (p.e., alteração da vegetação ripária, condição morfológica e carga de sedimentos) não permitiram o estabelecimento de condições de referência adequadas para os rios desta região, foi proposto um procedimento alternativo baseado numa combinação de dois métodos – modelação e filtros ambientais. A aplicação deste procedimento na definição de condições de referência revelou-se útil para lidar com os efeitos das alterações globais na biomonitorização com recurso a comunidades de diatomáceas e macroinvertebrados. De facto, como seria de esperar, as comunidades observadas em rios sujeitos a alterações antropogénicas revelaram-se menos homogéneas do que as previstas em condições de referência para esses mesmos rios, i.e., através da aplicação dos referidos filtros ambientais. Em conjunto com o desenvolvimento deste novo procedimento, foi também proposto um novo índice multimétrico de diatomáceas. Este novo índice revelou-se fortemente correlacionado com as pressões selecionadas, fornecendo uma avaliação da qualidade biológica mais abrangente do que o índice oficial adotado por Portugal, o Indice de Polluosensibilité spécifique (IPS). Para responder à segunda questão global apenas um subconjunto de ribeiras da região litoral de Portugal foi selecionado, o qual engloba as ribeiras cujos leitos secaram durante uma vaga de calor invulgar que ocorreu em Portugal em 2011/2012. Verificou-se que, de facto, quer as comunidades de diatomáceas quer de macroinvertebrados foram afetadas pelo evento de seca extrema tendo-se observado alterações ao nível das proporções de traits, composição e a classificação da qualidade biológica. No entanto, as diatomáceas apresentaram uma recuperação significativamente mais rápida que os macroinvertebrados. Os tipos de substratos usados na experiência de mesocosmos realizada neste trabalho (duro vs. macio; pequena escala espacial) também mostraram afetar as comunidades de diatomáceas, uma vez que houve diferenças quer na sua composição quer nas proporções de traits. Esta resposta ao tipo de substrato foi mais evidente em condições físico-químicas controladas do que aquela sugerida pelas diferenças entre as comunidades epipsâmicas e epilíticas dos rios monitorizados neste trabalho. Não obstante, durante a experiência de mesocosmos verificou-se que ao nível de IPS as diferenças entre substratos não eram relevantes quando comparadas com as que se haviam verificado nos rios. As diferenças observadas entre as comunidades de diatomáceas dos vários continentes (Europa, América e Austrália) sugerem que variações ao nível da grande escala também ocasionam diferenças nas comunidades, apesar de influenciados pelo mesmo tipo de clima. Isto sugere que outros factores para além do clima (p.e., geologia, processos biogeográficos históricos e hidrologia) podem ter contribuído para as diferenças inter-continentais verificadas ao nível da composição das comunidades de diatomáceas, a todos os níveis taxonómicos estudados. De um modo geral, os resultados obtidos durante este estudo trazem novas informações e novas abordagens para lidar com a biomonitorização. No entanto, mais trabalho será necessário a fim de investigar, por exemplo, os efeitos do aumento da temperatura previstos devido ao aquecimento global na avaliação da qualidade da água com base em comunidades de diatomáceas.

As yet, few explicit, practical and easy to implement marking scales for evaluating the quality of translations have been proposed. The purpose of this study is to introduce a new marking guide for making quantitative assessments of the quality of non-literary translations, and to test its practicality through a case study using the Arabic language. On the basis of the results, some generalizations about translation and translation quality assessment are made. Early treatments which dealt with the evaluation of translations are discussed, showing their merits and defects. The new marking guide is then described, including classification of errors and examples of each type of error. Guidelines are presented for the holistic subjective assessment, the guidelines are evaluated and the outcome discussed
Master of Arts (Hons)

Дисертація присвячена вирішенню науково-прикладного завдання забезпечення єдності вимірювань об’єму та об’ємної витрати природного газу шляхом удосконалення методів та пристроїв забезпечення оцінювання відповідності метрологічних характеристик засобів для обліку природного газу. Проведені теоретичні дослідження фізичних процесів в дзвонових еталонних установках. Здійснено аналітичне моделювання впливу гідродинамічних процесів на фронтальний оп ір при наближенні дзвона до дна кільцевого резервуара з обертовим стабілізуючим кільцем. Змодельований вплив юта нахилу дзвона еталонної установки на її похибку. Розроблена методологія кореляційного аналізу сигналів інформативних параметрів для оцінювання стабільності відтворюваної витрати дзвоновими установками. Розроблений метод визначення коефіцієнтів вагомості для оцінювання комплексного показника якості лічильників газу. Теоретично та методологічно вдосконалено передавання одиниці об’ємної витрати газу від державного первинного еталона до еталонів на базі критичних сопел. Обґрунтовано і вперше здійснено практичну апробацію процедури міждержавних звірень національних еталонів одиниць об’єму та об’ємної витрати газу за участю державного первинного еталона України з використанням спеціальних еталонних засобів передавання одиниці. Розроблені і впроваджені у практику нормативні документи, які забезпечують оцінювання відповідності засобів для обліку природного газу.
Dissertation for the degree of candidate of technical sciences, specialty 05.01.02 -standardization, and certification. - Ivano-Frankivsk National Technical University of Oil and Gas, Ivano-Frankivs’k, 2012. The thesis is devoted to solving scientific and applied tasks to ensure traceability volume and volumetric flow of natural gas through improved methods and devices to ensure conformity assessment metrological characteristics of accounting for natural gas. Theoretical study of physical processes in the bell of standard installations. Analytical modeling of hydrodynamic processes in the frontal resistance when approaching the bottom of the bell ring tank with rotating stabilizing ring. Modeled impact angle bell reference installation on its accuracy. Methodology correlation analysis of signals informative parameters for evaluating the stability of playing costs bell installations. The developed method for determining the weight coefficients for evaluating complex quality gas meters. Theory and measurement improved transmission unit volumetric flow of gas from the state primary standard to standards-based critical nozzles. Proved and the first time a practical testing procedures of international comparisons of national measurement standards unit volume and volumetric flow of gas with state primary standard of Ukraine with special reference of tire transmission unit. Developed and introduced into practice regulations that provide conformity assessment of accounting for natural gas.

A key factor in designing 3D systems is to understand how different visual cues and distortions affect the perceptual quality of 3D video. The ultimate way to assess video quality is through subjective tests. However, subjective evaluation is time consuming, expensive, and in most cases not even possible. An alternative solution is objective quality metrics, which attempt to model the Human Visual System (HVS) in order to assess the perceptual quality. The potential of 3D technology to significantly improve the immersiveness of video content has been hampered by the difficulty of objectively assessing Quality of Experience (QoE). A no-reference (NR) objective 3D quality metric, which could help determine capturing parameters and improve playback perceptual quality, would be welcomed by camera and display manufactures. Network providers would embrace a full-reference (FR) 3D quality metric, as they could use it to ensure efficient QoE-based resource management during compression and Quality of Service (QoS) during transmission. In this thesis, we investigate the objective quality assessment of stereoscopic 3D video. First, we propose a full-reference Human-Visual-system based 3D (HV3D) video quality metric, which efficiently takes into account the fusion of the two views as well as depth map quality. Subjective experiments verified the performance of the proposed method. Next, we investigate the No-Reference quality assessment of stereoscopic video. To this end, we investigate the importance of various visual saliency attributes in 3D video. Based on the results gathered from our study, we design a learning based visual saliency prediction model for 3D video. Eye-tracking experiments helped verify the performance of the proposed 3D Visual Attention Model (VAM). A benchmark dataset containing 61 captured stereo videos, their eye fixation data, and performance evaluations of 50 state-of-the-art VAMs is created and made publicly available online. Finally, we incorporate the saliency maps generated by our 3D VAM in the design of the state-of-the- art no-reference (NR) and also full-reference (FR) 3D quality metrics.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

Kritickým prvkem biometrického systému pro rozpoznávání otisků prstů je proces snímání. Kvalita snímku totiž ovlivňuje všechny další části systému počínaje zpracováním obrazu, přes extrakci rysů až po samotné rozhodnutí. Přestože bylo navrženo několik metod určování kvality snímku, chybějící formální specifikace kvality otisku nedovoluje ověřit jejich přesnost. Tato diplomová práce se zabývá hodnocením metod určujících kvalitu biometrického signálu otisku prstu. Popisuje jednotlivé faktory ovlivňující kvalitu spolu se současnými přístupy používanými pro její odhad. V práci je rovněž vysvětlena evaluační technika navržená za účelem porovnání schopnosti jednotlivých metod předpovědět výkon biometrického systému. Několik metod pro odhad kvality bylo implementováno a ohodnoceno touto technikou.

L'empreinte digitale est l'une des modalités les plus fiables en biométrie et donc a été largement étudié et déployés dans des applications réelles. La précision d'un système d'identification automatique d'empreintes digitales (AFIS) dépend largement de la qualité des échantillons d'empreintes digitales. La dégradation de la qualité d'empreinte digitales impacte le taux d'erreur lors de l'étape de vérification biométrique. Cette thèse se concentre principalement sur l'évaluation des mesures de qualité biométriques et plus précisément l'évaluation de la qualité des empreintes digitales (FQA), à partir d'une image en niveaux de gris et ou à partir de l'ensemble de minuties associées. En faisant un examen à la fois raffinée des systèmes biométriques et des méthodes d'évaluation en préliminaire, cette thèse contribue tout d'abord par la proposition d'un nouveau cadre d'évaluation/de validation pour estimer la performance de métriques de qualité biométriques. Le cadre d'évaluation / validation est défini dans la phase d'enrôlement en utilisant des essais hors ligne. La validité d'une mesure de qualité biométrique peut être statistiquement mesurée par la dégradation du d'égale erreur (EER) et les intervalles de confiance (IC) associés. Ensuite, cette thèse porte principalement sur l'évaluation de l'empreinte digitale de plusieurs façons, qui comprend trois parties dans le contexte de la FQA, où chacune d'entre elles est positionnée à partir d'une revue systématique de la littérature des études existantes. Tout d'abord, une approche d'évaluation de la qualité basée sur de multiples fonctionnalités et un avant-connaissance du rendement correspondant est proposé dans cette thèse, image d'empreinte digitale de qualification qui réalise avec des schémas de fusion et d'apprentissage et observe certains problèmes potentiels de ce type de solution. Deuxièmement, un nouvel algorithme FQA est proposé en utilisant uniquement modèle minuties image d'empreinte digitale de. Cette approche démontre la possibilité pour estimer la qualité d'image d'empreinte digitale avec le modèle de minuties seul. Troisièmement, un autre cadre FQA est réalisée via approche multi-segmentation image d'empreinte digitale, ce qui donne une nouvelle solution de cette question de la. Pendant ce temps, toutes les approches FQA proposé dans cette thèse offrent une étude comparative de cette question, pour les algorithmes FQA proposées sont en mesure de reprèsenter chaque solution reprèsentant parmi les études existantes
Digital fingerprint is one of the most reliable modality in modern biometrics and hence has been widely studied and deployed in real applications. The accuracy of one Automatic Fingerprint Identification System (AFIS) largely depends on the quality of fingerprint samples, as it has an important impact on the degradation of the matching (comparison) error rates. This thesis mainly focuses on the valuation of biometric quality metrics and fingerprint quality assessment (FQA), particularly in estimating the quality of gray-level fingerprint images or represented by a minutiae set. By making a refined review of both biometric systems and relevant evaluation techniques, this thesis firstly contributes by the definition of a new evaluation/validation framework for estimating the performance of biometric quality metrics. The evaluation/validation framework is defined in the enrollment phase by using onine trials. The validity of a biometric quality metric can be statistically measured by the degradation of the global Equal Error Rates (EER) and the associated Condence Intervals (CIs). Next, this thesis makes effort mainly in assessing fingerprint image quality in several different ways which include three parts in the context of the FQA, where each of them is proposed in terms of a systematic literature review of the existing studies of this issue. First, a quality assessment approach based on multiple features and a prior-knowledge of matching performance is proposed in this thesis, which achieves qualifying fingerprint image with fusion and learning schemes and observes some potential problems of this kind of solution. Second, a new FQA algorithm using the Delaunay triangulation is proposed to estimate the quality of a digital fingerprint via only its minutiae template. This approach demonstrates the possibility for estimating the quality of digital fingerprint with the minutiae template alone. Third, another FQA framework is carried out via multi-segmentation approach of fingerprint image, which gives a new solution of this problem. Meanwhile, all the proposed FQA approaches in this thesis provide a comparative study of this issue, for the proposed FQA algorithms are able to represent each representative solution among the existing studies

In broadcasting, the assessment of video quality is mostly done by a group of highly experienced people. This is a time consuming task and demands lot of resources. In this thesis the goal is to investigate the possibility to assess perceived video quality with the use of objective quality assessment methods. The work is done in collaboration with Telenor Satellite Broadcasting AS, to improve their quality verification process from a broadcasting perspective. The material used is from the SVT Fairytale tape and a tape from the Norwegian cup final in football 2009. All material is in the native resolution of 1080i and is encoded in the H.264/AVC format. All chosen compression settings are more or less used in daily broadcasting. A subjective video quality assessment been carried out to create a comparison basis of perceived quality. The subjective assessment sessions carried out by following ITU recommendations. Telenor SBc provided a video quality analysing system, the Video Clarity Clearview system that contains the objective PSNR, DMOS and JND. DMOS and JND are two pseudo-subjective assessment methods that use objective methods mapped to subjective results. The methods hopefully predict the perceived quality and eases quality assessment in broadcasting. The correlation between the subjective and objective results is tested with linear, exponential and polynomial fitting functions. The correlation for the different methods did not achieve a result that proved use of objective methods to assess perceived quality, independent of content. The best correlation result is 0.75 for the objective DMOS method. The analysis shows that there are possible dependencies in the relationship between subjective and objective results. By measuring spatial and temporal information possible dependent correlation results are investigated. The results for dependent relationships between subjective and objective results are good. There are some indications that the two pseudo-subjective methods, JND and DMOS, can be used to assess perceived video quality. This applies when the mapping functions are dependent on spatial and temporal information of the reference sequences. The correlation achieved for dependent fitting functions, that has a suitable progression, are in the range 0.9 -- 0.98. In the subjective tests, the subjects used were non-experts in quality evaluation. Some of the results indicate that subjects might have a problem with assessing sequences with high spatial information. This thesis creates a basis for further research on the use of objective methods to assess the perceived quality.

Subjective video quality is a subjective characteristic of video quality. It is concerned with how a video is perceived by the viewer and designates his or her opinion on the particular video sequence. Subjective video quality tests are quite expensive in terms of time (preparation and running) and human resources. The main objectives of this testing is how the human observes the video quality since they are the ultimate end user. There are many ways of testing the quality of the videos. We have used ITU-T Recommendation P.910.
In our research work, we have designed the tool that can be used to conduct a mass-scale level survey or subjective tests. ACR is the only method used to carry out the subjective video assessment. The test is very useful in the context of a video streaming quality. The survey can be used in various countries and sectors with low internet speeds to determine the kind of video or the compression technique, bit rate, or format that gives the best quality.
0700627491, 0760935352

Proteins are crucial for all living organisms and they are involved in many different processes. The function of a protein is tightly coupled to its structure, yet to determine the structure experimentally is both non-trivial and expensive. Computational methods that are able to predict the structure are often the only possibility to obtain structural information for a particular protein. Structure prediction has come a long way since its inception. More advanced algorithms, refined mathematics and statistical analysis and use of machine learning techniques have improved this field considerably. Making a large number of protein models is relatively fast. The process of identifying and separating correct from less correct models, from a large set of plausible models, is also known as model quality assessment. Critical Assessment of Techniques for Protein Structure Prediction (CASP) is an international experiment to assess the various methods for structure prediction of proteins. CASP has shown the improvements of these different methods in model quality assessment, structure prediction as well as better model building. In the two studies done in this thesis, I have improved the model quality assessment part of this structure prediction problem for globular proteins, as well as trained the first such method dedicated towards membrane proteins. The work has resulted in a much-improved version of our previous model quality assessment program ProQ, and in addition I have also developed the first model quality assessment program specifically tailored for membrane proteins.

QC 20120313

Two tasks that software engineers constantly perform are writing code that is easy to evolve and maintain, and detecting poorly written pieces of code. For the former, software engineers commonly rely on well-known software architecture styles, such as Model-View-Controller (MVC). To the latter, they rely on code metrics and code smell detection approaches. However, up to now, these code metrics and code smell approaches do not take into account underlying architectureall classes are assessed as if they were the same. In practice, software developers know that classes differ in terms of responsibilities and implementation, and thus, we expect these classes to present different levels of coupling, cohesion, and complexity. As an example, in an MVC system, Controllers are responsible for the flow between the Model and the View, and Models are responsible for representing the systems business concepts. Thus, in this thesis, we evaluate the impact of architectural roles within a system architecture on code metrics and code smells. We performed an empirical analysis in 120 open source systems, and interviewed and surveyed more than 50 software developers. Our findings show that each architectural role has a different code metric values distribution, which is a likely consequence of their specific responsibilities. Thus, we propose SATT, an approach that provides specific thresholds for architectural roles that are significantly different from others in terms of code smells. We also show that classes that play a specific architectural role contain specific code smells, which developers perceive as problems, and can impact class\' change- and defect-proneness. Based on our findings, we suggest that developers understand the responsibilities of each architectural role in their system architecture, so that code metrics and code smells techniques can provide more accurate feedback.
Duas tarefas que desenvolvedores de software constantemente fazem são escrever código fácil de ser mantido e evoluído, e detectar pedaços de código problemáticos. Para a primeira tarefa, desenvolvedores comumente fazem uso de conhecidos padrões arquiteturais, como Model-View-Controller (MVC). Para a segunda tarefa, desenvolvedores fazem uso de métricas de código e estratégias de detecção de maus cheiros de código (code smells). No entanto, até o momento, métricas de código e estratégias de detecção de maus cheiros de código não levam em conta a arquitetura do software em análise. Isso significa que todas classes são avaliadas como se umas fossem iguais às outras. Na prática, sabemos que classes são diferentes em suas responsibilidades e implementação, e portanto, esperamos que elas variem em termos de acoplamento, coesão e complexidade. Por exemplo, em um sistema MVC, Controladores são responsáveis pelo fluxo entre a camada de Modelo e a camada de Visão, e Modelos representam a visão de negócios do sistema. Nesta tese, nós avaliamos o impacto dos papéis arquiteturais em técnicas de medição de métricas de código e de detecção de maus cheiros de código. Nós realizamos um estudo empírico em 120 sistemas de código aberto, e entrevistamos e realizamos questionários com mais de 50 desenvolvedores. Nossos resultados mostram que cada papel arquitetural possui distribuições diferentes de valores de métrica de código, consequência das diferentes responsabilidades de cada papel. Como consequência, propomos SATT, uma abordagem que provê thresholds específicos para papéis arquiteturais que são significantemente diferentes de outros em termos de métricas de código. Mostramos também que classes que cumprem um papel arquitetural específico também contêm maus cheiros de código específicos. Esses maus cheiros são percebidos por desenvolvedores como problemas reais e podem fazer com que essas classes sejam mais modificadas e apresentem mais defeitos do que classes limpas. Sugerimos então que desenvolvedores entendam a arquitetura dos seus sistemas, bem como as responsabilidades de cada papel arquitetural que as classes desempenham, para que tanto métricas de código quanto estratégias de detecção de maus cheiros de código possam prover um melhor retorno.

This thesis explores challenging topic of information system quality assessment and mainly process assessment. In this work the term Information System Quality is defined as well as different approaches in a quality definition for different domains of information systems are outlined. Main methods of process assessment are overviewed and their relationships are described. Process assessment methods are divided into two categories: ISO standards and best practices. The main objective of this work is application of gained theoretical knowledge in process assessment with CobiT 4.1 and CobiT 5.0 frameworks, and comparing results. The objective was achieved through consultation with processes owner and the completed questionnaires filled in by management of OnLine S.r.l. Additionally targeted level of capability in CobiT 5.0 is compared with actual, achieved level.

Abstract. The quality assessment of signal has been a research topic for many years, as it is mainly related to the problem of the false alarms. Automatic quality detection/assessment and classification of signals can play a vital role in the development of robust unsupervised electrocardiogram (ECG). The development of efficient algorithms for the quality control of ECG recordings is essential to improve healthcare now. ECG signal can be intermixed with many kinds of unwanted noises. It is an important task to assess the quality of the ECG signal for further biomedical inspections. To make that happen, we made an algorithm that is efficient and uses some basic quality features to classify the ECG signals. It is a very effective way to acquire a good quality ECG signal in real-time by unskilled personnel for instance in rural areas there is not enough expertise in this field. By using this method, they can quickly know if the ECG signal is acceptable or unacceptable for further inspections. The method is used to assess the quality of the ECG signals in the training set of the Physionet/Computing in Cardiology Challenge 2011, giving a correct interpretation of the quality of the ECG signals of 93.08% which corresponded to a sensitivity of 96.53% and a specificity of 86.76%.

73 pp.
Originally developed in Iowa and adapted for Arizona. Arizona Youth Livestock Quality Assurance Member Manual; Arizona Youth Livestock Quality Assurance Activity Guide.
This trainer's reference is for use in implementing the youth livestock quality assurance program. The curriculum is designed to provide youth and adults with a better understanding of the risks involved in the food production industry, better understand the Good Production Practices (GPP's) that can help them produce a safer product and therefore, implement these GPP's in their own livestock production system.

The object of this thesis is to provide, through a thorough analysis of human perception and interaction with aesthetics and landscape quality, a comprehensive basis on which to develop a credible methodology for the large scale assessment of perceived landscape quality. The analysis of human perception and interaction with aesthetics and landscape quality is gained by inquiring in depth into a range of theoretical constructs from key disciplines, cultural aspects, and empirical studies covering : 1. the contribution of philosophers to aesthetics 2. the psychology of perception and colour 3. the contribution of Gestalt psychology to aesthetics 4. the psychoanalytical construct of human responses to aesthetics 5. the influence of culture on landscape preferences, tracing the changing perceptions of mountains, the portrayal of landscapes in art, and the design of parks and gardens 6. a review of over 200 surveys of landscape quality in the late 20th century, including typologies and theories of landscape quality Based on the analysis of these and the knowledge gained, an empirical study is formulated and conducted, comprising a study of landscape quality of South Australia, an area of nearly 1 million km - 1. This involves, firstly, the acquisition of data covering the delineation of landscape character regions for the State, photography of these landscapes, derivation of a set of representative slides, and rating of these by groups of participants. Secondly, these preference ratings are comprehensively analysed on the basis of the attributes of the scenes covering land form, land cover, land use, water bodies, naturalism, diversity and colour. Thirdly, the results are applied as follows: 1. a map of landscape quality of South Australia is derived 2. the results are used to predict the effect that changes in land use ( e.g. clearance of trees ) will have on landscape quality 3. the theoretical constructs of landscape quality are evaluated on the basis of the preference ratings 4. a protocol is detailed to guide the undertaking of large - scale landscape quality assessment. The thesis thus fulfils the objective of conducting a thorough analysis of human perception and interaction with, aesthetics and landscape quality, to provide a basis for developing a credible methodology for the large - scale assessment of perceived landscape quality.
Thesis (Ph.D.)--School of Social Sciences, 2000.

Thesis (Ph. D.)--University of California, San Diego, 2007.
Title from first page of PDF file (viewed Mar. 14, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 149-156).

This study approaches wood quality in young trees by very early screening – and consequent selection for propagation – on the basis of physical and mechanical properties. In chapter 1 corewood properties are reviewed and the importance and problems associated with early screening are discussed. Due to randomly distributed reaction wood in young trees it is advantageous to lean trees to avoid intermixing of the two wood types and minimise any uncertainty in the results. In chapter 2 physical and mechanical properties are described for opposite and compression wood in a population of Pinus radiata comprising of 50 families, at a young (<3 years) age. The dynamic stiffness was determined using the resonance acoustic technique. Density was measured using water displacement method, and longitudinal and volumetric shrinkage were measured from green to ~5% moisture content. The compression wood and opposite wood differ significantly in all the measured properties. Compression wood was characterised by high density and high longitudinal shrinkage. The mean stiffness of opposite wood was 3.0 GPa with a mean standard deviation of 0.39, and the mean longitudinal shrinkage of opposite wood was 0.99% with mean standard deviation of 0.31 across the samples examined. This variation in stiffness and longitudinal shrinkage in opposite wood can be exploited to screen for wood quality. The variation in stiffness and longitudinal shrinkage within a family was comparable to variation among families. In spite of large within site variability it was possible to distinguish between the worst and the best families in opposite wood at young age. In chapter 3 ranking of selected families of Pinus radiata was done based on microfibril angle, which is considered as the main factor influencing both stiffness and longitudinal shrinkage. The ranking was compared with ranking done using acoustic velocity which is more practical and fast method of screening trees. The mean MFA in opposite wood was 39° with a mean standard deviation of 3.7 and in compression wood the mean MFA was 44° with a mean standard deviation of 2.9. The variation in MFA in opposite wood offers opportunities to breed for trees with low MFA. A strong negative correlation (R=-0.68) between acoustic velocity squared and MFA in opposite wood suggested that the resonance technique can be used effectively to screen very young wood rather than using MFA. At high MFA, the cell wall matrix also plays an important role in determining the mechanical and physical properties of the wood. At present the chemical composition of wood samples is determined by wet chemical analysis, which is time consuming and laborious. Therefore, it is impractical to characterise large numbers of samples. Mechanical properties, particularly tanδ (dissipation of energy), which changes with temperature and frequency as the structure of the material changes at the molecular level, was studied using dynamic mechanical analysis (DMA). The idea was to assess if it can be used as a quality trait for tree screening instead of wet chemical analysis. Compression wood and opposite wood were characterised for storage modulus and tanδ at constant moisture content. In practice the instrument used, TA instrument Q800, was unable to provide the desired range of temperature and humidity so no glass transition at 9% moisture content in the temperature range of 10°C to 85°C at 1 and 10 Hz frequency was observed that might be attributed to the hemicelluloses (or lignin). In spite of the huge difference in chemical composition of opposite and compression wood, the difference in their mean tanδ at 25°C and 1 Hz values was just 7%. The positive correlation between MFA and tanδ in opposite wood suggested that MFA also plays a role in the dissipation of energy. The strong relationship between storage modulus and dynamic modulus (R=0.74) again justifies the reliability of resonance technique to screen young wood for stiffness. Concurrently eighty seven, two-year-old leant Eucalyptus regnans were studied for growth strains along with other physical and mechanical properties, independently in tension and opposite wood. The leant trees in Eucalyptus regnans vary in their average growth strain. Strong correlation between measured and calculated strain (R=0.93) suggests that the quick split method can be used to screen large populations for growth stresses. Tension wood was characterised by high density and was three times stiffer than opposite wood and twice as high in volumetric shrinkage. The high longitudinal shrinkage in opposite wood could be due to comparatively high MFAs in opposite wood of the young trees. There was no correlation between growth strain values and other measured properties in opposite wood. It is possible to screen for growth strain at age two, without any adverse effect on stiffness and shrinkage properties.

This study brings together two bodies of literature, one concerned with the character of services and the other concerned with the nature of quality, in order to explore the nature and possible forms of measurement of service quality. It uses the conference hotel service product as a vehicle for examining judgements about overall service quality. A systematic approach, through a multi-staged methodology, is evolved by first identifying what the product consists of; secondly by establishing what the evaluative attributes are; thirdly by assessing levels of perceived performance on the evaluative attributes and, crucially, the assessment of the overall performance of the product. By using statistical techniques, the evaluative attributes of perceived net quality are examined. This is achieved by analysing which attributes fulfil minimum requirements and which attributes can increase a positive perception of net quality. In addition, the impact of the attributes on net quality is established. The study shows that the specific product consists of a multi-dimensional combination of attributes in varying degrees. The crucial attribute is shown to be dependability of management and staff. In addition, the study reveals that net quality is not only a reflection of incidents of satistaction with the physical - commodities and performed activities. It also needs to take into consideration human interaction as a component in itself. In a wider context the study gives an indication of how the perceived net quality of a product , with a high degree of an activity component, can be examined.

This thesis discusses quality assessment of audio communications systems, in particular telephone networks. A new technique for time-delay estimation based on a smoothed weighted histogram of frame-by-frame delays is presented. This has low complexity and is found to be more robust to non-linear distortions typical of telephone networks. This technique is further extended to identify piecewise constant delay, enabling models to be used for assessing packet-based transmission such as voice over IP, where delay may change several times during a measurement. It is shown that equalisation improves the accuracy of perceptual models for measurements that may include analogue or acoustic components. Linear transfer function estimation is found to be unreliable due to non-linear distortions. Spectral difference and phaseless cross-spectrum estimation methods for identifying and equalising the linear transfer function are implemented for this application, operating in the filter-bank and short-term Fourier spectrum domains. This thesis provides the first detailed examination of the process of selecting and mapping multiple objective perceptual distortion parameters to estimated subjective quality. The systematic variation of subjective opinion between tests is examined and addressed using a new method of monotonic polynomial regression. The effect on conventional regression techniques, and a new joint optimisation process, are considered.

Godkänd; 2016; 20160126 (musalj); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Mustafa Aljumaili Ämne: Drift och underhållsteknik/Operation and Maintenance Engineering Avhandling: Data Quality Assessment: Applied in Maintenance Opponent: Docent Mirka Kans, Institutionen för Maskinteknik, Linnéuniversitetet, Växjö. Ordförande: Professor Uday Kumar, Avdelning för Drift, underhåll och akustik, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet. Tid: Fredag 4 mars 2016, kl 10.00 Plats: F1031, Luleå tekniska universitet

Advances in image quality assessment have shown the benefits of modelling functional components of the human visual system in image quality metrics. Visual saliency, a crucial aspect of the human visual system, is increasingly investigated recently. Current applications of visual saliency in image quality metrics are limited by our knowledge on the relation between visual saliency and quality perception. Issues regarding how to simulate and integrate visual saliency in image quality metrics remain. This thesis presents psychophysical experiments and computational models relevant to the perceptually-optimised use of visual saliency in image quality metrics. We first systematically validated the capability of computational saliency in improving image quality metrics. Practical guidance regarding how to select suitable saliency models, which image quality metrics can benefit from saliency integration, and how the added value of saliency depends on image distortion type were provided. To better understand the relation between saliency and image quality, an eye-tracking experiment with a reliable experimental methodology was first designed to obtain ground truth fixation data. Significant findings on the interactions between saliency and visual distortion were then discussed. Based on these findings, a saliency integration approach taking into account the impact of distortion on the saliency deployment was proposed. We also devised an algorithm which adaptively incorporate saliency in image quality metrics based on saliency dispersion. Moreover, we further investigated the plausibility of measuring image quality based on the deviation of saliency induced by distortion. An image quality metric based on measuring saliency deviation was devised. This thesis demonstrates that the added value of saliency in image quality metrics can be optimised by taking into account the interactions between saliency and visual distortion. This thesis also demonstrates that the deviation of fixation deployment due to distortion can be used as a proxy for the prediction of image quality.

Doutoramento em Biologia
Estuaries are poles of attraction for human settlement which is a source of pressures to surface water bodies. The implementation of the European Water Framework Directive (WDF, 2000/60/EC) has increased the investigation in order to develop methodologies to assess the Ecological Quality Status (EQS) of aquatic ecosystems. Transitional systems are naturally stressed and characterized by highly dynamic physical, chemical and hydro-morphologic conditions and by species with a higher level of tolerance to change, being more difficult to develop suitable quality indicators for these systems. The general purpose of this study is to test the ability of synthesis descriptors, including primary (S, taxa richness) and derived biological variable (H’, Shannon-Wiener diversity), biotic indices (AMBI and M-AMBI), body size properties (abundance distribution by body size classes, length, weight and length-weight relationships) and non-taxonomic indices (ISS), as well as functional indicators related to the decomposition rates of various experimental substrates, a macrophyte (Phragmites australis) and an alga (Fucus vesiculosus), to evaluate the environmental quality in transitional systems. This study was carried out in one of the most pristine channels of the Ria the Aveiro, Mira Channel, along a full salinity gradient and in a metals and metalloid sediment contamination area, the Estarreja Channel, and two reference channels (Canelas and Salreu). In this study were used different sampling techniques, the leaf-bag technique and a hand-held corer. In Mira Channel, the alga and the macrophyte presented an opposite trend in the decomposition rate along the salinity gradient, with the decomposition rates of the alga always higher than those of the macrophyte. The decomposition rates of the macrophyte and the alga were higher in the mid estuary and in higher salinity areas, respectively, corresponding to the preferencial distribution areas of each species. The macrobenthic fauna associated with the decaying and an artificial substrate (control) showed equally well the benthic succession from the marine to the freshwater areas and, despite the strong differences in the decay rates, no significant differences were found between the benthic communities associated with the alga and the macrophyte. The body size properties of the macrobenthic fauna associated with the P. australis leaf-bag (1mm and 5mm) and corer samples were studied along the full salinity gradient. The dominant species of the sub-set of measured specimens were not the same of the original macrobenthic fauna sampled but, despite that, the sub-set of measured specimens was also able to show the benthic succession from the marine to the freshwater areas. The body size abundance distribution of the benthic macroinvertebrates according to the ISS size classes did not show a particular trend in any sampler along the salinity gradient. Significant differences were found in the length, weight and length-weight relationships of Annelids, , Molluscs and even some species along the salinity gradient. No significant differences were found in the AMBI, M-AMBI and ISS values along the salinity gradient for all the samplers. The EQS of the corer samples obtained using the M-AMBI was lower than that of the leaf-bags. The EQS obtained with the ISS was higher than that obtained with the M-AMBI in the leaf-bags but not in the corer samples. The ecological effects of contaminated sediments associated with the industrial chemical effluents discharged in the Estarreja Channel were studied a decade after ceasing the emissions, using the Sediment Quality Triad approach and two reference channels. The results showed that despite the emissions ceased in 2004, the sediment remains polluted with high levels of metals and metalloid, available to bioaccumulation and with severe consequences at the community level. The sediment contamination problem was also studied using the leaf-bag technique with a macrophyte, an alga and a control substrate. The results showed that the decay rates, the associated macrofauna and the application of the AMBI, M-AMBI and ISS indices to the mesh-bag samples were not able to identify the sediment contamination. Contrarily to the AMBI, the M-AMBI and the ISS showed significant differences between the contaminated and the reference channels for the corer samples. Although such statistical significance, the interest of using these complex biotic indices could be questioned, when much simple ones, like the S and H’ allow to reach the same conclusions.
Os estuários são pólos de atração para a instalação de aglomerados humanos, constituindo uma fonte de pressão para as massas de água superficiais. Com a implementação da Diretiva Europeia Quadro da Água (DQA, 2000/60/CE) tem aumentado a investigação no sentido de desenvolver metodologias para avaliar o estado de qualidade ecológica (EQE) dos ecossistemas aquáticos. Os sistemas de transição são caracterizados por condições físico-químicas e hidromorfológicas extremamente dinâmicas e por espécies com uma maior tolerância à mudança, sendo difícil desenvolver indicadores de qualidade adequados para estes ecossistemas. O objetivo deste estudo é testar a capacidade de descritores de síntese, tais como a riqueza em espécies (S) e a diversidade de Shannon-Wiener (H'), índices de base taxonómica (AMBI e M-AMBI) e não taxonómica (ISS), as propriedades do tamanho corporal (distribuição de abundância por classes de tamanho corporal, comprimento, peso e relações comprimento-peso), bem como indicadores funcionais (taxas de decomposição de uma macrófita (Phragmites australis) e uma alga (Fucus vesiculosus)), para avaliar a qualidade ambiental dos sistemas de transição. Este estudo foi realizado ao longo de um gradiente completo de salinidade num dos canais com menor impacto antropogénico da Ria de Aveiro, o Canal de Mira, numa área com contaminação sedimentar por metais e metaloides, o Canal de Estarreja, e dois canais de referência (Canelas e Salreu). Neste estudo foram utilizadas diferentes técnicas de amostragem, a técnica dos sacos de folha e corers. No Canal de Mira, a alga e a macrófita apresentaram uma tendência oposta na taxa de decomposição ao longo do gradiente de salinidade, com as taxas de decomposição da alga sempre superiores. As taxas de decomposição da macrófita e da alga foram mais elevadas a meio do estuário e em áreas de maior salinidade, respetivamente, correspondendo às preferenciais áreas de distribuição de cada espécie. A fauna bentónica associada aos substratos orgânicos e a um substrato artificial (controlo) mostrou a sucessão bentónica ao longo do gradiente estuarino e, apesar das grandes diferenças nas taxas de decomposição, não foram encontradas diferenças nas comunidades bentónicas entre ambos os substratos. As propriedades do tamanho corporal da fauna bentónica dos sacos de folhas de P. australis (1mm e 5mm) e corers foram estudadas ao longo do gradiente estuarino. As espécies dominantes do sub-conjunto de espécimes medidos não são as mesmas da fauna bentónica original mas, apesar disso, foram capazes de mostrar a sucessão bentónica ao longo do gradiente salino. A distribuição da abundância pelas classes de tamanho estabelecidas para o cálculo do índice ISS não mostrou nenhuma tendência ao longo do gradiente de salinidade em nenhum dos amostradores. Foram encontradas diferenças significativas no comprimento, peso e na relação comprimento-peso dos Anelídeos, Artrópodes, Moluscos e de algumas espécies ao longo do gradiente de salinidade. Não foram encontradas diferenças significativas nos valores AMBI, M-AMBI e ISS ao longo do gradiente estuarino. O EQE das amostras dos corer foi inferior ao dos sacos de folhas. O EQE obtido com o ISS foi mais elevado do que o obtido com o M-AMBI nos sacos de folha, mas não nas amostras do corer. Os efeitos ecológicos associados à contaminação dos sedimentos por efluentes químicos lançados no Canal de Estarreja foram estudados uma década após a sua cessação, recorrendo à Tríade de Qualidade Sedimentar e dois canais de referência. Os resultados mostraram que o sedimento permanece contaminado com elevados níveis de metais e metaloide, disponíveis para serem bioacumulados e com graves consequências ao nível da comunidade. A contaminação do sedimento foi também estudada utilizando a técnica dos sacos de folhas com a macrófita, a alga e um substrato de controlo, tendo-se verificado que as taxas de decomposição, a macrofauna associada e a aplicação dos índices AMBI, M-AMBI e ISS aos sacos de folhas não foram capazes de identificar o problema. Ao contrário do AMBI, o M-AMBI e o ISS apresentaram diferenças significativas entre o canal contaminado e os canais de referência para as amostras do corer. No entanto, a utilização de índices tão complexos é questionável, na medida em que índices mais simples, tais como a S e a H', permitem chegar às mesmas conclusões.

Class of 2007 Abstract
Objectives: The purpose of this study is to assess the quality of study medications obtained without a prescription through international websites. Methods: Samples of levothyroxine, warfarin, and sildenafil were obtained through various websites and compared to U.S. standards. Each sample was physically evaluated for weight, color, shape, and external tablet markings. High performance liquid chromatography (HPLC) was performed to quantify the amount of active ingredient. Results: When physically inspected, only 3 of the 9 lots met FDA labeling requirements. Three of 60 (20 tablets from 3 lots) of the individual levothyroxine tablets were out of the USP acceptable range (90% - 110%). For warfarin, 16 of the 60 samples (20 samples from 3 lots) of the individual tablets were out of the USP acceptable range (95% - 105%). When averaged, each of the lots for both levothyroxine and warfarin were within their USP acceptable ranges. As sildenafil is not available as generic in the U.S., there is no USP standard acceptable range for comparison. All of the sildenafil samples fell within 90%- 105% of Viagra® tablets obtained from a local pharmacy. Conclusions: While there were a few samples outside of the U.S. acceptable range, the majority of samples analyzed for active ingredient were within the range published in the USP. While the outcomes of this study presented interesting findings, further evaluation in larger studies is needed to properly assess the quality of foreign medications purchased over the internet.

Context: The newest standard in video coding High Efficiency Video Coding (HEVC) should have an appropriate coder to fully use its potential. There are a lot of video quality assessment methods. These methods are necessary to establish the quality of the video. Objectives: This thesis is a comparison of video quality assessment methods. Objective is to find out which objective method is the most similar to the subjective method. Videos used in tests are encoded in the H.265/HEVC standard. Methods: For testing MSE, PSNR, SSIM methods there is special software created in MATLAB. For VQM method downloaded software was used for testing. Results and conclusions: For videos watched on mobile device: PSNR is the most similar to subjective metric. However for videos watched on television screen: VQM is the most similar to subjective metric. Keywords: Video Quality Assessment, Video Quality Prediction, Video Compression, Video Quality Metrics