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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Visual Assessment of Rivers and Marshes: An Examination of the Relationship of Visual Units, Perceptual Variables and Preference

Ellsworth, John C. 01 May 1982 (has links)
The purpose of this research was to examine the relationship of two approaches to visual assessment of landscape--the qualitative descriptive inventory and the theoretically-based empirical perceptual preference approach. Three levels of landscape visual units based on bio-physical similarities (landscape units, setting units, and waterscape units) were identified in a marsh (CUtler Reservoir, Cache County , Utah), and its tributary streams. Color slide photographs were taken from five of the visual units. These slides were rated on a 5- point scale by panels of judges for the expression of four perceptual variables--coherence, complexity, mystery, and legibility. The same slides were rated on a 5-point scale by 98 respondents according to their preference for each slide. The relationship of the visual units, perceptual variables, and preference was evaluated by analytical and statistical procedures. Results showed significant differences in the expression of the four perceptual variables between rivers and marshes and between setting units~ Both rivers and marshes were considered coherent when there were similarities in vegetation within the respective types; however, the strong horizontal organization of the marsh scenes necessary for coherence contrasted with the edge definition and orderliness considered necessary in rivers. Mystery was also related to similar factors in rivers and marshes (such as obscuring vegetation, particularly in the marsh) but the presence of riverbanks and bends in the river corridor had a distinct effect on mystery ratings in the river scenes . Complexity in both rivers and marshes was primarily dependent on diversity of vegetation and visual depth , but the number of different visual elements in river scenes also influenced complexity. Legibility was related to straight, enclosed and simple corridors in river images and to simple spaces with regular vegetation in marsh images. Fine textures and clear spatial definition enhanced legibility. Preference ratings were significantly different between rivers and marshes, but not between river setting units or waterscape units. River scenes received higher preference ratings than marsh scenes. Mystery , complexity, and visual depth were especially important to preference. Demographic variables of age, sex, academic major, and home state did not significantly affect preference. Statistical analysis indicated each perceptual variable was an independent predictor, and that compared to visual units, perceptual variables were more strongly related to preference.
2

Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?

Levy, Mark Reinhardt 11 December 2009 (has links)
Landscape visual preference research has indicated many potential indicators of preference; however a comprehensive framework concerning the relationship between visual preference and perception has not been solidified. Gestalt psychology, the predecessor to visual perception, proposes certain visual grouping tendencies to explain how humans perceive the world. This study examines if Gestalt grouping principles are reliable indicators of preference, and if they may be used to develop a broad context for visual assessment. Visual preference for 36 landscape scenes testing the proximity and similarity of landscape elements were ranked one through five by 1,749 Mississippi State University undergraduate, graduate, and faculty members in a web-based preference survey. Using a two-way between groups analysis of variance (ANOVA) to analyze responses, the results indicate that the proximal and similar configuration of landscape elements within a scene does significantly affect visual preference.
3

Public aesthetic preferences and efficient water use in urban parks

Bitar, Hassan January 2004 (has links) (PDF)
Local governments in Melbourne are rethinking the design of parks with the aim of increasing water efficiency. In changing park design to achieve this objective, community landscape aesthetic expectations need also to be considered if these changes are to be socially acceptable. Using a psychophysical approach of landscape assessment, this thesis examines the relationship between public perceptions of park environments in Melbourne and water consumption. The thesis first develops a perceptual classification of a sample of landscapes found in Melbourne’s urban park system. Secondly, it investigates the meanings, perceptions and aesthetic and general preferences the public associate with these park landscapes. Thirdly, it estimates the relative water-use of landscape plantings associated with these park landscapes. Finally, it develops a systematic approach to balancing the public aesthetic expectations and water-use in urban parks. (For complete abstract open document)
4

Seeing and measuring the 2D face

Hayes, Susan January 2009 (has links)
This is a study of the factors that affect face shapes, and the techniques that can be used to measure variations in two dimensional representations of faces. The materials included thirty photographs of people in natural poses and thirty portraits that were based on the pose photographs. Visual assessors were asked to score the photographs and portraits in terms of pose (cant, turn and pitch) and also to compare the portraits to the photographs and score them in terms of likeness in the depiction of the face and its component features. Anthropometric indices were derived and used to score the images for the pose variables as well as for aspects of individual variation in external face shape and the spatial arrangement of the features. Geometric morphometric analysis was also used to determine the shape variation occurring in the photographs, the variation within the portraits, and to specifically discern where the portraits differ from the photographs in the depiction of head pose and individual differences in facial morphology. For the analysis of pose it was found that visual assessors were best at discerning the extent of head turning and poorest at discerning head pitch. These tendencies occurred in the visual assessments of both the photographs and the portrait drawings. For the analysis of the individual variation in face shapes it was found that external face shape varies according to upper face dimensions and the shape of the chin, and that vertical featural configurations are strongly linked to external face shape. When the portrait and photograph data were placed in the same geometric morphometric analysis the inaccuracies in the portrait drawings became evident. When these findings were compared to the visual assessments it transpired that, on average, visual assessment was generally congruent with the geometric morphometric analysis, but were possibly confounded by patterns of dysmorphology in the portraits that were contrary to what this study suggests are normal patterns of face shape variation. Overall this study has demonstrated that while anthropometric and visual assessments of facial differences are quite good, both were comparatively poor at assessing head pitch and tended to be confounded by the dysmorphologies arising in the portrait drawings. Geometric morphometric analysis was found to be very powerful in discerning complex shape variations associated with head pose and individual differences in facial morphology, both within and between the photographs and portraits.
5

Níveis de exposição a vapores orgânicos e consequências psicofísicas, neurocognitivas e fisiológicas em uma amostra de frentistas brasileiros

Campos Neto, Armindo de Arruda 06 December 2013 (has links)
Made available in DSpace on 2015-05-14T13:16:23Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3324327 bytes, checksum: b85304a7fe276b9b7697e2cdf5a23471 (MD5) Previous issue date: 2013-12-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed at verifying exposure levels for gasoline and ethanol vapors and their psychophysical, neurocognitive, and physiological consequences in a sample of Brazilian pump attendants. Gas chromatography and microclimate sensing were used to passive and active monitoring of environmental levels of vapors. The psychophysical evaluation comprised the chromatic tests Lanthony D15-d and Cambridge Color Test 2.0, the Contrast Sensitivity Function using vertical sinusoidal gratings and Metropsis at the frequencies 0.2, 0.5, 1.0, 2.0, 5.0, 10.0, and 16.0 cpd, and eye-tracking at 250 Hz. Except by the D15-d test, all vision tests were performed with the dominant eye. The neurocognitive evaluation included the Trial Making Tests (A and B) and the Rey's Complex Figure Test. After applying exclusion criteria, the physiological evaluation was carried out in 16 attendants, who had a blood test to assess hepatic-biliary functions by the following markers: Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Direct Bilirubin (DB), Total Bilirubin (TB), and Gamma-glutamyl transpeptidase (GAMMA GT). The screening phase also included a questionnaire of Psychological and Neurophysiological Symptoms (PNS), a sociodemographic questionnaire, the Ishihara and the Rasquin 'E' tests. Thirty-eight pump attendants (Exposed Group) were selected, all males, with mean age of 32.66 years (SD = 1.30) and average schooling of 9.68 years (SD = 0.34). Thirty-eight volunteers (Control Group) were selected, all males, with mean age of 30.0 years (SD = 1.54), average schooling of 9.84 years (SD = 0.34), without reporting exposure to solvents and considered healthy following the inclusion criteria. The groups did not differ in age (p = .224) or schooling (p = .52), and all participants had normal or corrected-to-normal visual acuity 20/20. The Mann-Whitney test showed significant differences between scores in the Index of Color Confusion of the D15-d (p < .01, with losses in the tritan axis 75%), the Area of ellipses (protan, deutran, and tritan, all at p < .05), the frequencies 5, 10, and 16 cpd (p < .01), the Trail Making A (p < .01) and B (p < .05), the copy and memory of the Rey's complex figure (both at p < .01), and the number of saccades and trajectory time in the visual labyrinth (both at p < .01) as measure by the eye-tracker. The physiological evaluation showed changes in the values of DB (100 % of the pump attendants) and TB (62,5 %). Two attendants had combined changes in hepatic enzymes and biliburin. The Spearman correlation showed a significant association between the time of service and the areas protan (ρ = .46, p < .01) and deutan (ρ = .64, p < .01), the spatial frequency 5 cpd (ρ = .36, p < .05), and the Trail Making A (ρ = .40, p < .05) and B (ρ = .37, p < .05). The weight showed a tendency to attenuate the visual deficits, having a negative correlation with the area deutan (ρ = - .45, p < .01) and a positive one with contrast sensitivity at 0.20 cpd (ρ = .37, p < .05). Correlations were also found between DB and the time to perform the eye-tracker task (ρ = .58, p < .05) and the GGT and complaints of psychoneurovegetative instability (ρ = .57, p < .05). The Kruskal Wallis, and Mann-Whitney as a post-hoc test with Bonferroni's correction, showed that from 8 years of exposure there are consequences to color vision (Protan and Deutan) and for neurocognitive processes related to attention (Trail Making). The questionnaire PNS showed that 52.6% of pump attendants had symptoms of neuropsychological aggressions. Furthermore, there was a convergence between memory and attention complaints, with lower scores in the memory for the Rey's complex figure (ρ = - .34, p < .05). This study brings additional and new evidences for the consequences on color vision and contrast sensitivity, shows a potential occupational etiology in hepatic-biliary changes, presents neurocognitive xviii deficits in Brazilian pump attendants, and concludes that such deficits are correlated with chronic exposure (significant from 8 years of service) with a level of exposure to gasoline and ethanol below the Brazilian tolerance limit, but within an intervention level to gasoline vapor (168 and 153,40 ppm > 150 ppm) according to the Brazilian Standards for Work Health and Safety. / O objetivo deste estudo foi determinar os níveis de exposição aos vapores da gasolina e do etanol e verificar as consequências psicofísicas, neurocognitivas e fisiológicas em uma amostra de frentistas brasileiros. Para avaliar o nível de exposição ambiental foram realizados monitoramentos passivos e ativos de vapor com cromatografia gasosa e sensoriamento microclimático. A avaliação psicofísica foi realizada com os testes cromáticos de Lanthony D15-d e o Cambridge Color Teste 2,0; com a Função de Sensibilidade ao Contraste utilizando grades senoidais verticais e o Metropsis nas frequências 0,2; 0,5; 1,0; 2,0; 5,0; 10,0 e 16,0 cpg e com o rastreamento ocular utilizando um eyetracker 250 Hz. Todos os testes de visão, exceto o D15-d, foram realizados monocularmente com o olho dominante. A avaliação neurocognitiva ocorreu com os testes Trail Making A, B e com a Figura Complexa de Rey. A avaliação fisiológica, após utilização de parâmetros de exclusão, foi realizada pela análise de sangue de 16 frentistas verificando funções hepatotóxicas pelos marcadores Alanina Aminotransferase (ALT), Aspartato Aminotransferase (AST), Bilirrubina Direta (BD), Bilirrubina Total (BT) e Gamaglutamiltraspeptidase (GGT). Utilizou-se ainda o questionário de sintomas Psicológicos e Neurofisiológicos (PNF) além de um questionário sóciodemográfico e os testes de Ishihara e o ―E‖ de Rasquin na triagem. Essa etapa selecionou 38 frentistas do sexo masculino (Grupo Exposto), com idade média de 32,66 anos (DP = 1,30), grau de escolaridade média igual a 9,68 anos de estudo (DP = 0,34) e 38 voluntários (Grupo Controle) também do sexo masculino, sem histórico de exposição a solventes, considerados saudáveis pelos parâmetros de exclusão, com idade média de 31,00 anos (DP = 1,54) e grau de escolaridade médio de 9,84 anos de estudo (DP = 0,34). Não existiu diferença significativa entre a idade (p = 0,224) e o grau de escolaridade (p = 0,52) dos grupos que apresentaram ainda acuidade visual de 20/20 ou corrigida. Pelo teste de Mann-Whitney foram encontradas diferenças significativas entre os escores para: o Índice de Confusão de Cores do teste D15-d (p < 0,01, prevalecendo perdas no eixo tritan 75%), as Áreas das elipses (protan, deutan e tritan, ambos p < 0,05), as frequências 5 cpg, 10 cpg e 16 cpg (ambos p < 0,01), o teste Trail Making A (p < 0,01) e B (p < 0,05), a cópia e a memória da Figura complexa de Rey (ambas p < 0,01) e o número de sacadas e tempo de percurso do labirinto no eyetracker (ambos p < 0,01). A avaliação biológica demonstrou principalmente alterações nos valores da BD (100 % dos frentistas) e BT (62,5 %). Dois frentistas tiveram alterações combinadas de enzimas hepáticas e bilirrubinas. A correlação de Spearman demonstrou a influência do tempo de serviço no acréscimo das áreas protan (ρ = 0,46; p < 0,01) e deutan (ρ = 0,64; p < 0,01), além de correlações com a frequência de 5 cpg (ρ = 0,36; p < 0,05) e com os testes Trail Making A (ρ = 0,40; p < 0,05) e B (ρ = 0,37; p < 0,05). O peso apresentou a tendência de atenuar os déficits nos testes de visão, correlacionando negativamente com a área deutan (ρ = - 0,45; p < 0,01) e positivamente com a sensibilidade ao contraste na frequência 0,20 cpg (ρ = 0,37; p < 0,05). Existiram ainda correlações entre a BD e o tempo para realizar a prova no eyetracker (ρ = 0,58; p < 0,05) e entre o GGT e as queixas de instabilidade psiconeurovegetativa (ρ = 0,57; p < 0,05). Os testes Kruskal Wallis, e Mann- Whitney como post hoc com correção Bonferroni, demonstraram que a partir de 8 anos de exposição existem consequências para a visão de cores (Protan e Deutan) e para processos neurocognitivos relacionados a atenção (Trail Making A). O questionário PNF apontou que 52,60 % dos frentistas possuem sintomas de agressões neuropsicológicas. Além disso, existiram convergências entre as queixas de falta de memória e concentração, com menores pontuações da memória na Figura Complexa de Rey (ρ = - 0,34; p < 0,05). Este estudo confirma e avança nas descobertas de consequências na visão de cores e sensibilidade ao contraste, aponta uma possível etiologia ocupacional nas alterações hepatotóxicas, apresenta as deficiências neurocognitivas nos frentistas brasileiros e conclui que essas deficiências e as da visão de cores estão correlacionadas a uma exposição crônica (significativa aos 8 anos de serviço) com um nível de exposição a gasolina e ao álcool etílico abaixo do Limite de Tolerância brasileiro, mas a um nível de intervenção para o vapor de gasolina (168,00 e 153,40 ppm > 150 ppm) conforme as Normas de Saúde e Segurança do Trabalho brasileiras.
6

On the establishment of a data-driven approach to gravel road maintenance

Mbiyana, Keegan January 2023 (has links)
Gravel roads are essential for economic development as they facilitate the movement of people, transportation of goods and services, and promote cultural and social development. They typically connect sparsely populated rural areas to urban centres, providing essential access for residents and entrepreneurs. Maintaining these roads to an acceptable level of service is crucial for the efficient and safe transportation of goods and services. However, substantial maintenance investmentis required, yet resources are limited. Gravel roads are prone to dust, potholes, corrugations, rutting and loose gravel. They deteriorate faster than paved roads, and their failure development is affected by traffic action and physical, geometric and climatic factors. Thus, more condition monitoring and proper road condition assessment are necessary for dynamic maintenance planning to reach efficiency and effectiveness using objective, data-driven condition assessment methods to ensure all-year-round access. However, objective data-driven methods (DDMs) are not frequently used for gravel road condition assessment, and where they have been applied, the practical implementation is limited. Instead, visual windshield assessment and manual methods are predominant. Visual assessments are unreliable and susceptible to human judgement errors, while manual methods are time-consuming and labour-intensive. Maintenance activities are predetermined despite dynamic maintenance needs, and the planning is based on historical failure data rather than the actual road condition. This thesis establishes a data-driven approach to gravel road maintenance describing the systematic assessment of the gravel road condition and collection of the condition data to ensure efficient and effective maintenance planning. This thesis uses a design research methodology based on a literature review, concept development, interview study and field experiments. A holistic approach is proposed for data-driven maintenance of gravel roads encompassing objective condition data collection, processing, analysing, and interpreting the findings for obtaining reliable information concerning the condition to gravel road decision support by utilising the opportunities presented by technological advancements, particularly sensor technology. Then, decision-making is primarily influenced by the objectively collected gravel road condition data rather than the evaluator’s perception or experience. The successful implementation of a data-driven approach depends on the quality of the collected data; therefore, data relevance and quality are emphasised in this thesis. The lack of data quality and relevance hinders effective data utilisation, leading to less precisionin decision-making and ineffective decisions. Furthermore, the thesis proposes a participatory data-driven approach for unpaved road condition monitoring, allowing road users to be part of the maintenance process and providing an efficient and effective alternative for collecting road condition data and accomplishing broad coverage at minimum cost. A top-down iiapproach for data-driven gravel road condition classification is proposed to achieve an objective assessment to address the lack of readily available quality and relevant condition data. The established data-driven approach to gravel road maintenance is evaluated and verified with field experiments on three gravel roads in Växjö municipality, Southern Sweden. The research findings indicate that properly implementing a data-driven approach to gravel road maintenance would ensure efficient and effective condition assessment and classification, which are a basis for a maintenance management system of gravel roads and enable road maintainers and authorities to achieve cost-effective decision-making. / Sustainable maintenance of gravel road
7

Evaluation of flood damage on cross laminated timber wall configurations

Kaya, Mustafa Nezih 09 August 2022 (has links) (PDF)
Greenhouse gas emissions are one of the critical factors that affect climate change, increasing flooding risk and threatening human life. The use of traditional construction materials is responsible for a higher percentage of global greenhouse gas emissions when compared to the use of sustainable materials in the construction industry. The substitution of current building materials with sustainable materials is essential to reduce greenhouse gas emissions and positively influence climate change when the current construction demand in the world is considered. Wood is one of the primary environmentally friendly construction materials in regard to high carbon storage and low carbon emissions. Cross-laminated timber (CLT) is prefabricated and this type of composite wood material is convenient for constructing middle to high rise buildings because materials are able to be cut to specific specifications which lowers onsite labor time. This research observed the hygrothermal behavior of partially submerged CLT wall panels during the wetting and drying period and simulated the flooding of the panels with a software tool, Wärme Und Feuchte Instationär (WUFI). The higher number of CLT layers caused a slower water penetration rate throughout the layers with a lower water absorption rate corresponding to the first layer than the other layers, so the water was primarily retained in the first layer. Also, water penetration through axial direction significantly decreased due to gravity impact when the height of CLT panels was increased. The visual assessment showed that the 3-day-wetted CLT panel configurations did not show any type of fungi growth through the wetting and drying period. However, both untreated and treated CLT panels with the envelope system did have fungi growth on the drywall after a 20-day-wetting period.
8

Uso de propriedades visuais-interativas na avaliação da qualidade de dados / Using visual-interactive properties in the data quality assessment

Josko, João Marcelo Borovina 29 April 2016 (has links)
Os efeitos dos dados defeituosos sobre os resultados dos processos analíticos são notórios. Aprimorar a qualidade dos dados exige estabelecer alternativas a partir de vários métodos, técnicas e procedimentos disponíveis. O processo de Avaliação da Qualidade dos Dados - pAQD - provê relevantes insumos na definição da alternativa mais adequada por meio do mapeamento dos defeitos nos dados. Relevantes abordagens computacionais apoiam esse processo. Tais abordagens utilizam métodos quantitativos ou baseados em asserções que usualmente restringem o papel humano a interpretação dos seus resultados. Porém, o pAQD depende do conhecimento do contexto dos dados visto que é impossível confirmar ou refutar a presença de defeitos baseado exclusivamente nos dados. Logo, a supervisão humana é essencial para esse processo. Sistemas de visualização pertencem a uma classe de abordagens supervisionadas que podem tornar visíveis as estruturas dos defeitos nos dados. Apesar do considerável conhecimento sobre o projeto desses sistemas, pouco existe para o domínio da avaliação visual da qualidade dos dados. Isto posto, este trabalho apresenta duas contribuições. A primeira reporta uma taxonomia que descreve os defeitos relacionados aos critérios de qualidade da acuracidade, completude e consistência para dados estruturados e atemporais. Essa taxonomia seguiu uma metodologia que proporcionou a cobertura sistemática e a descrição aprimorada dos defeitos em relação ao estado-da-arte das taxonomias. A segunda contribuição reporta relacionamentos entre propriedades-defeitos que estabelecem que certas propriedades visuais-interativas são mais adequadas para a avaliação visual de certos defeitos em dadas resoluções de dados. Revelados por um estudo de caso múltiplo e exploratório, esses relacionamentos oferecem indicações que reduzem a subjetividade durante o projeto de sistemas de visualização de apoio a avaliação visual da qualidade dos dados. / The effects of poor data quality on the reliability of the outcomes of analytical processes are notorious. Improving data quality requires alternatives that combine procedures, methods, techniques and technologies. The Data Quality Assessment process - DQAp - provides relevant and practical inputs for choosing the most suitable alternative through a data defects mapping. Relevant computational approaches support this process. Such approaches apply quantitative or assertions-based methods that usually limit the human interpretation of their outcomes. However, the DQAp process strongly depends on data context knowledge since it is impossible to confirm or refute a defect based only on data. Hence, human supervision is essential throughout this process. Visualization systems belong to a class of supervised approaches that can make visible data defect structures. Despite their considerable design knowledge encodings, there is little support design to data quality visual assessment. Therefore, this work reports two contributions. The first reports a taxonomy that organizes a detailed description of defects on structured and timeless data related to the quality criteria of accuracy, completeness and consistency. This taxonomy followed a methodology which enabled a systematic coverage of data defects and an improved description of data defects in regard to state-of-art literature. The second contribution reports a set of property-defect relationships that establishes that certain visual and interactive properties are more suitable for visual assessment of certain data defects in a given data resolution. Revealed by an exploratory and multiple study case, these relationships provides implications that reduce the subjectivity in the visualization systems design for data quality visual assessment.
9

Uso de propriedades visuais-interativas na avaliação da qualidade de dados / Using visual-interactive properties in the data quality assessment

João Marcelo Borovina Josko 29 April 2016 (has links)
Os efeitos dos dados defeituosos sobre os resultados dos processos analíticos são notórios. Aprimorar a qualidade dos dados exige estabelecer alternativas a partir de vários métodos, técnicas e procedimentos disponíveis. O processo de Avaliação da Qualidade dos Dados - pAQD - provê relevantes insumos na definição da alternativa mais adequada por meio do mapeamento dos defeitos nos dados. Relevantes abordagens computacionais apoiam esse processo. Tais abordagens utilizam métodos quantitativos ou baseados em asserções que usualmente restringem o papel humano a interpretação dos seus resultados. Porém, o pAQD depende do conhecimento do contexto dos dados visto que é impossível confirmar ou refutar a presença de defeitos baseado exclusivamente nos dados. Logo, a supervisão humana é essencial para esse processo. Sistemas de visualização pertencem a uma classe de abordagens supervisionadas que podem tornar visíveis as estruturas dos defeitos nos dados. Apesar do considerável conhecimento sobre o projeto desses sistemas, pouco existe para o domínio da avaliação visual da qualidade dos dados. Isto posto, este trabalho apresenta duas contribuições. A primeira reporta uma taxonomia que descreve os defeitos relacionados aos critérios de qualidade da acuracidade, completude e consistência para dados estruturados e atemporais. Essa taxonomia seguiu uma metodologia que proporcionou a cobertura sistemática e a descrição aprimorada dos defeitos em relação ao estado-da-arte das taxonomias. A segunda contribuição reporta relacionamentos entre propriedades-defeitos que estabelecem que certas propriedades visuais-interativas são mais adequadas para a avaliação visual de certos defeitos em dadas resoluções de dados. Revelados por um estudo de caso múltiplo e exploratório, esses relacionamentos oferecem indicações que reduzem a subjetividade durante o projeto de sistemas de visualização de apoio a avaliação visual da qualidade dos dados. / The effects of poor data quality on the reliability of the outcomes of analytical processes are notorious. Improving data quality requires alternatives that combine procedures, methods, techniques and technologies. The Data Quality Assessment process - DQAp - provides relevant and practical inputs for choosing the most suitable alternative through a data defects mapping. Relevant computational approaches support this process. Such approaches apply quantitative or assertions-based methods that usually limit the human interpretation of their outcomes. However, the DQAp process strongly depends on data context knowledge since it is impossible to confirm or refute a defect based only on data. Hence, human supervision is essential throughout this process. Visualization systems belong to a class of supervised approaches that can make visible data defect structures. Despite their considerable design knowledge encodings, there is little support design to data quality visual assessment. Therefore, this work reports two contributions. The first reports a taxonomy that organizes a detailed description of defects on structured and timeless data related to the quality criteria of accuracy, completeness and consistency. This taxonomy followed a methodology which enabled a systematic coverage of data defects and an improved description of data defects in regard to state-of-art literature. The second contribution reports a set of property-defect relationships that establishes that certain visual and interactive properties are more suitable for visual assessment of certain data defects in a given data resolution. Revealed by an exploratory and multiple study case, these relationships provides implications that reduce the subjectivity in the visualization systems design for data quality visual assessment.

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