Cotton crop condition was assessed from an analysis of multispectral aerial video imagery. Visible-near infrared imagery of two cotton fields was collected towards the end of the 1990 crop. The digital analysis was based on image classification, and the accuracies were assessed using the Kappa coefficient of agreement. The earliest of three images proved to be best for distinguishing plant variety. Vegetation index images were better for estimating potential yield than the original multispectral image; so too were multi-channel images that were transformed using vegetation indices or principal component analysis. The seedbed preparation rig used, the nitrogen application rate and three plant varieties, a weed species and two cotton cultivars, could all be discriminated from the imagery. Accuracies were moderate for the discrimination of plant variety, tillage treatment and nitrogen treatment, and low for the estimation of potential yield.

<p>The Kappa coefficient is widely used in assessing categorical agreement between two raters or two methods. It can also be extended to more than two raters (methods).  When using Kappa, the shortcomings of this coefficient should be not neglected.  Bias and prevalence effects lead to paradoxes of Kappa. These problems can be avoided by using some other indexes together, but the solutions of the Kappa problems are not satisfactory. This paper gives a critical survey concerning the Kappa coefficient and gives a real life example. A useful alternative statistical approach, the Rank-invariant method is also introduced, and applied to analyze the disagreement between two raters.</p>

The Kappa coefficient is widely used in assessing categorical agreement between two raters or two methods. It can also be extended to more than two raters (methods).  When using Kappa, the shortcomings of this coefficient should be not neglected.  Bias and prevalence effects lead to paradoxes of Kappa. These problems can be avoided by using some other indexes together, but the solutions of the Kappa problems are not satisfactory. This paper gives a critical survey concerning the Kappa coefficient and gives a real life example. A useful alternative statistical approach, the Rank-invariant method is also introduced, and applied to analyze the disagreement between two raters.

Made available in DSpace on 2014-12-17T15:55:04Z (GMT). No. of bitstreams: 1 GabriellaCMS_DISSERT.pdf: 3451606 bytes, checksum: 1ee33015b3633fb79771b6160bff6a6c (MD5) Previous issue date: 2013-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The municipality of Areia Branca is within the mesoregion of West Potiguar and within the microregion of Mossor?, covering an area of 357,58 km2. Covering an area of weakness in terms of environmental, housing, together with the municipality of Grossos-RN, the estuary of River Apodi-Mossor?. The municipality of Areia Branca has historically suffered from a lack of planning regarding the use and occupation of land as some economic activities, attracted by the extremely favorable natural conditions, have exploited their natural resources improperly. The aim of this study is to quantify and analyze the environmental degradation in the municipality. Thus initially was performed a characterization of land use using remote sensing, geoprocessing and geographic information system GIS in order to generate data and information on the municipal scale, which may serve as input to the environmental planning and land use planning in the region. From this perspective, were used a Landsat 5 image TM sensor for the year 2010. In the processing of this image was used SPRING 5.2 and applied a supervised classification using the classifier regions, which was employed Bhattacharya Distance method with a threshold at 30%. Thus was obtained the land use map that was analyzed the spatial distribution of different types of the use that is occurring in the city, identifying areas that are being used incorrectly and the main types of environmental degradation. And further, were applied the methodology proposed by Beltrame (1994), Physical Diagnosis Conservationist under some adaptations for quantifying the level of degradation or conservation study area. As results, the indexes were obtained for the parameters in the proposed methodology, allowing quantitatively analyze the degradation potential of each sector. From this perspective, considering a scale of 0 to 100, sector A and sector B had value 31.20 units of risk of physical deterioration. And the C sector, has shown its value - 34.64 units degradation risk and should be considered a priority in relation to the achievement of conservation actions / O munic?pio de Areia Branca-RN est? inserido na mesorregi?o Oeste Potiguar e na microrregi?o de Mossor?, abrangendo uma ?rea de 357,58 km2. Compreende uma ?rea de fragilidade do ponto de vista ambiental, pois abriga, juntamente com o munic?pio de Grossos- RN, o estu?rio do rio Apodi-Mossor?. O munic?pio de Areia Branca vem sofrendo historicamente com a falta de planejamento no tocante ao uso e ocupa??o do solo, uma vez que algumas atividades econ?micas, atra?das pelas condi??es naturais favor?veis, t?m explorado os recursos naturais de forma inadequada. O objetivo deste estudo ? quantificar e analisar a degrada??o ambiental no referido munic?pio. Para isso, inicialmente foi realizada uma caracteriza??o do uso do solo, utilizando sensoriamento remoto, geoprocessamento e um sistema de informa??es geogr?ficas - SIG, visando gerar dados e informa??es na escala municipal, que possam servir de subs?dio para o planejamento ambiental e o ordenamento territorial da regi?o. Nessa perspectiva, utilizou-se uma imagem Landsat 5, sensor TM referente ao ano de 2010. No processamento desta imagem foi utilizado o SPRING 5.2 e aplicado uma classifica??o supervisionada atrav?s do classificador por regi?es, onde foi empregado o m?todo Bhattacharya Distance com um limiar 30%. Com isso foi obtido o mapa de uso do solo a partir do qual analisou-se a distribui??o espacial dos diferentes tipos de uso que ocorrem no munic?pio, identificando ?reas que est?o sendo utilizadas de maneira incorreta e os principais tipos de degrada??o ambiental. Em prosseguimento, aplicou-se a metodologia proposta por Beltrame (1994), o Diagn?stico F?sico-Conservacionista, sob algumas adapta??es, para obter a quantifica??o do n?vel de degrada??o ou conserva??o da ?rea de estudo. Como resultados, foram obtidos os ?ndices para os par?metros propostos na metodologia, permitindo analisar quantitativamente o potencial de degrada??o de cada setor. Nessa perspectiva, considerando uma escala de 0 a 100, o setor A e o setor B apresentaram valor 31,20 unidades de risco de degrada??o f?sica. E o setor C, demonstrou valor 34,64 unidades de risco de degrada??o, devendo ser considerado prioridade no tocante ? realiza??o de a??es conservacionistas

Introduction Colour codes are used extensively in railways to convey specific information governing movement of trains and equipment on the track. One such task is the railway traffic control display that uses colour coded video display terminals (VDTs) to convey information of the signal status, train movements and track status to the railway dispatcher. Because individuals with colour vision deficiencies (colour-defectives) may have problems with these colour-related tasks, questions were raised about the suitability of colour vision defectives to work as railway dispatchers. In order to answer that, a VDT based Dispatch Colour Vision Test based on the actual railway traffic display was developed previously. Purpose The main purpose of this thesis is to establish the pass/fail scores and repeatability of the VDT based Dispatch Colour Vision Test that resulted from the previous work. Secondly, the study will also examine whether clinical colour vision tests can predict the performance on the practical task. Methods The Dispatch colour vision test was divided into three parts based on the colour sets that the dispatcher had to recognize. The testing computer system used the the same RGB colour settings, graphics card and monitor as in railway dispatch centres. Subjects viewed the display colours and entered their responses by using a mouse. One hundred colour-normals and fifty two colour-defectives participated in the initial session. The test was repeated approximately after 10 days. Ninety three colour-normals (93%) and 44 (85%) colour-defectives participated in the second session. The total number of errors and time to complete the test was recorded. Results Pass/Fail on the VDT Dispatch colour vision test was based on colour-normal errors. Ignoring orange-red errors, two errors were allowed in the first session and one error was allowed in the second session. Based on this criterion, 42% of colour vision defectives could perform as well as colour normal subjects. The kappa coefficient of agreement between the sessions for the colour-defectives was 0.85. Detailed analysis between the colour differences and the errors showed only a weak correlation between the two. However, the general trend was that colour-defectives made more errors on colours that were near or along the same lines of confusions and the colours were nearly equal in luminance. Nevertheless, the interaction between luminance and location with respect to the lines of confusion was not easy to interpret. The time to complete the task for the colour-defectives who passed the test took 14% longer than colour-normals and colour-defectives who failed took 30% longer than colour-normals. All groups showed a similar learning effect with an 18% reduction in mean times to complete the task at the second session. There was no significant correlation between the number of errors and time to complete or the clinical tests and completion times for any of the groups. Clinical colour vision tests have limited value in predicting performance of colour-defectives on the Dispatch test. Logistic analysis results showed that the Farnsworth D-15 along with the Nagel was the best predictor of the VDT Dispatch colour test pass/fail results. However, these results were similar to using the Farnsworth D-15 test alone. Ninety-five percent of the individuals who failed the Farnsworth D-15 also failed the Dispatch test. However, approximately 25% of the individuals who passed the Farnsworth D-15 failed the VDT Dispatch colour test which is an unacceptable false negative rate. These results indicate the Farnsworth D-15 can only be used to predict who is likely to fail the dispatch test. Conclusions Forty two percent of colour vision defectives could perform as well as colour-normals in identifying VDT railway display colours and time to complete the task. Clinical colour vision tests were inadequate predictors of performance in practical task, overall. However, the Farnsworth D-15 was a very good predictor of who would fail the VDT Dispatch test. Hence a practical VDT Dispatch test may be needed to test individuals who would want to work as railway dispatchers.

Introduction Colour codes are used extensively in railways to convey specific information governing movement of trains and equipment on the track. One such task is the railway traffic control display that uses colour coded video display terminals (VDTs) to convey information of the signal status, train movements and track status to the railway dispatcher. Because individuals with colour vision deficiencies (colour-defectives) may have problems with these colour-related tasks, questions were raised about the suitability of colour vision defectives to work as railway dispatchers. In order to answer that, a VDT based Dispatch Colour Vision Test based on the actual railway traffic display was developed previously. Purpose The main purpose of this thesis is to establish the pass/fail scores and repeatability of the VDT based Dispatch Colour Vision Test that resulted from the previous work. Secondly, the study will also examine whether clinical colour vision tests can predict the performance on the practical task. Methods The Dispatch colour vision test was divided into three parts based on the colour sets that the dispatcher had to recognize. The testing computer system used the the same RGB colour settings, graphics card and monitor as in railway dispatch centres. Subjects viewed the display colours and entered their responses by using a mouse. One hundred colour-normals and fifty two colour-defectives participated in the initial session. The test was repeated approximately after 10 days. Ninety three colour-normals (93%) and 44 (85%) colour-defectives participated in the second session. The total number of errors and time to complete the test was recorded. Results Pass/Fail on the VDT Dispatch colour vision test was based on colour-normal errors. Ignoring orange-red errors, two errors were allowed in the first session and one error was allowed in the second session. Based on this criterion, 42% of colour vision defectives could perform as well as colour normal subjects. The kappa coefficient of agreement between the sessions for the colour-defectives was 0.85. Detailed analysis between the colour differences and the errors showed only a weak correlation between the two. However, the general trend was that colour-defectives made more errors on colours that were near or along the same lines of confusions and the colours were nearly equal in luminance. Nevertheless, the interaction between luminance and location with respect to the lines of confusion was not easy to interpret. The time to complete the task for the colour-defectives who passed the test took 14% longer than colour-normals and colour-defectives who failed took 30% longer than colour-normals. All groups showed a similar learning effect with an 18% reduction in mean times to complete the task at the second session. There was no significant correlation between the number of errors and time to complete or the clinical tests and completion times for any of the groups. Clinical colour vision tests have limited value in predicting performance of colour-defectives on the Dispatch test. Logistic analysis results showed that the Farnsworth D-15 along with the Nagel was the best predictor of the VDT Dispatch colour test pass/fail results. However, these results were similar to using the Farnsworth D-15 test alone. Ninety-five percent of the individuals who failed the Farnsworth D-15 also failed the Dispatch test. However, approximately 25% of the individuals who passed the Farnsworth D-15 failed the VDT Dispatch colour test which is an unacceptable false negative rate. These results indicate the Farnsworth D-15 can only be used to predict who is likely to fail the dispatch test. Conclusions Forty two percent of colour vision defectives could perform as well as colour-normals in identifying VDT railway display colours and time to complete the task. Clinical colour vision tests were inadequate predictors of performance in practical task, overall. However, the Farnsworth D-15 was a very good predictor of who would fail the VDT Dispatch test. Hence a practical VDT Dispatch test may be needed to test individuals who would want to work as railway dispatchers.

This research work concentrate on developing digital soil maps to support field based plant phenotyping research. We have developed soil organic matter content (OM), cation exchange capacity (CEC), natural soil drainage class, and tile drainage line maps using topographic indices and aerial imagery. Various prediction models (universal kriging, cubist, random forest, C5.0, artificial neural network, and multinomial logistic regression) were used to estimate the soil properties of interest.