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Presentation, optmization and result of new methods of infiltration and neurolysis under CT guidance in the management of pain / Présentation, optimisation et résultats de nouvelles méthodes d'infiltrations et de neurolyses sous contrôle scanner dans la prise en charge de la douleurKastler, Adrian 12 December 2014 (has links)
Au cours des 20 dernières années, l'utilisation de méthode de guidage par imagerie s'est progressivemen imposé comme gold standar dans nombre d'indications Interventionel antidouleur. Les modalités de guidage els plus utilisés sont la fluoroscopie et l'échographie. Le Scanner est relativement sous-utilisé dans le domaine de la prise en charge interventionnelle de la douleur, principalement en raison des difficultés d'accès et de Disponibilités pour les praticiens de la douleur. Au travers de cette thèse, nous avons montré l'intérêt du guidage scanner dans plusieurs indications avec de bons résultats, grâce à des techniques innovantes* L'Évaluation de l'alcoolisation percutanée du ganglion sphéno-palatin dans la prise en charge de ladouleur cranio-faciale réfractaire, chez 42 patients avec taux d'efficacité globale d'alcoolisation du GSP de67,2% et une durée moyenne de soulagement de la douleur de 10,3 mois. L'analyse a montré un tauxd'efficacité élevé chez les patients avec des algies vasculaires de la face (76,5%) et des syndromesdouloureux faciaux persistent (85,7%)* L' Évaluation de l'efficacité d'un méthode simplifiée d'infiltration sous scanner du nerf grandoccipital (NGO) chez 33 patients souffrant d'une névralgie occipitale avec taux de succès clinique de 86%.En cas de succès clinique, la durée moyenne de soulagement de la douleur suivant la procédure était de9,16 mois.*La comparaison deu block vs. neurolyse par radiofréqence du ganglion stellaire sous guidage scannographique dans la prise en charge du Syndrome Douloureux Régional Complexe de Type 1 du membre supérieur chez 67 patients: on retrouve une efficacité supérieure dans le groupe RFN (67,6%, 23/34) par rapport au groupe de block (21,2%, 7/33) avec un OR de 7,76.* L'Évaluation de la neurolysepar RF des nerfs ilio-inguinal et ilio hypogastrique chez les patients souffrant de douleurs ilio-inguinal et à l'aine réfractaire.• pouvait conduire à une amélioration des résultats. Dans tous les cas, le guidage par Scanner est une valeur ajoutée dans certaines indications, car elle permet en toute sécurité, le placement précis, millimétrique, de l'aiguille. Une autre solution possible afin de réduire les risques liés à certains gestes serait le développement d'une L'Étude préliminaire sur 16 patients traités par RFN a montré une réduction significative dela douleur après RFN pendant 11,8 mois.• Une deuxième étude a été menée permettant de comparer l'efficacité de la RFN et à cellede l'infiltration dans la même indication chez 42 patients: La durée moyenne de soulagementde la douleur était statistiquement supérieure (P = 0,005) dans le groupe RF (12,5 mois)comparé au groupe d'infiltration (1,6 mois).Au cours de ces études publiées, nous avons montré que l'application d'une technique existante (neurolyse, infiltration) à une nouvelle indication, ou la modification d'une technique existante après des considérations anatomiques sonde de radiofréquence unidirectionnel, capable de créer une zone d'ablation en demi sphère dont l'orientation serait contrôlable, ce qui permettrait de réduire les risques d'ablation non désirée.Enfin, il est important de rappeler, que la prise en charge interventionnelle de la douleur d'un patient s'intègre dans une prise en charge globale, centrée autour du patient. Ainsi, la prise en charge d'un patient douloureux ne pourra se faire de manière efficace qu'en prenant en compte l'ensemble des aspects de la douleur exprimé par le patient, bien au delà des seules considérations techniques d'un geste interventionnel. / Over the past 20 years, the use of imaging guidance has progressively but very rapidly evolved to become a standard practice to date, with fluoroscopy and Ultrasound being the most popular imaging guiding tools. However, CT guidance is relatively underused in the field of Interventional pain management, mainly due to acces and availabilty issues for pain physicians. Therefore, the objective of this thesis are mulitple :* to evaluate the usefulness of CT scan guidance, in applying existing neurolytic techniques(block.infiltration and neurolysis) to innovative indications, allowed by the use of such an imagingguiding tool.* to evaluate the clinical effectiveness of these novel indications* Finally, to emphasize on the importance of the clinical aspects of Interventional pain managementAfter after having reminded the definitions of the different existing techniques (neural blocks, infiltration, neurolysis) and detailed existing materials (Local anesthestics, Steroids, Chemical Neurolysis, Physical Neurolysis), a brief description of existing indication of Interventional Pain will be made. Emphasis will then be made on the assessment of innovative interventional CT Guided pain techniques in various refractory pain syndromes :- Evaluation of Alcohol percutaneous neurolysis of the sphenopalatine ganglion in the management of refractory cranio facial pain , in 42 patients : overall efficacy rate of alcohol SPN was 67.2% with a mean pain relief duration of 10,3 months. Analysis showed a higher efficacy rate in patients with Cluster Headaches (76.5%) andPersisting Facial Idiopathic Pain (85.7%)- Evaluation of the efficacy of a simplified CT guided greater occipital nerve (GON) infiltration approach inthe management of occipital neuralgia (ON) in 33 patients : Clinical success rate was 86%. In case of clinicalsuccess, mean pain relief duration following procedure was 9.16 months.- Evaluation of CT-guided Stellate Ganglion Blockade vs. Radiofrequency Neurolysis in the Managementof Refractory type I Complex Régional Pain Syndrome of the Upper Limb in 67 patients : analysis performed onthe blockade and RFN groups showed a significantly (P<0.0001) higher success rate in the RFN group (67.6%,23/34) compared with thé blockade group (21.2%, 7/33) with an OR of 7.76.- Evaluation of CT Guided ilio inguinal (II) and ilio hypogastric Radiofrequency Neurolysis (RFN) inpatients with refractory ilio-inguinal and groin pain.* Preliminary Study on 16 patients treated with II RFN showed significant pain reductionafter RFN with a mean pain relief of 11,8 months.* A second study was conducted to compared the effectiveness of RFN and Infiltration in thesame indication in 42 patients : Mean duration of pain relief was statistically significant (P = .005)in the RF group (12.5 months) compared to the infiltration group (1.6 months).Throughout these published studies, we hâve shown that the application of an existing neurolytic technique in a new indication, or modifying an existing technique after anatomical considerations may lead to either higher efficacy rates, longer pain reliefs, or safer procedures. In ail cases, CT guidance is an added value to any procédures as it allows safe, précise accurate and effective needle placement in most procedures. Another possible solution to reduce procedure related risks discussed in this thesis, is the development of a unidirectional radiofrequency probe, capable of producing tissue destruction only on one half on the probe thereby creating a half mooned shaped thermal zone, which would reduce the risk of surrounding unwanted tissue damage. This topic merits further studies and development as possible everyday implications are numerous .
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Aprimoramento do método de estimação de gordura corporal em um Scanner 3D antropométrico / Improvement of a body fat mass estimation method through a 3D anthropometric ScannerMichel Alves Lacerda 03 August 2015 (has links)
Este trabalho apresenta o estudo realizado no aprimoramento de um método de estimação de gordura corpórea por meio de um Scanner antropométrico ALLBODYSCAN 3D® (São Carlos, SP, 2012) que constrói imagens 3D do corpo humano. Procedimentos computacionais de análise de modelo corporal gerado pelo scanner, têm sido desenvolvidos na USP. Este estudo considerou medições em voluntários de vários grupos de interesse, de forma que a estimação de gordura pudesse ter abrangência satisfatória e com poucos fatores de erro, aprimorando a técnica. A pesquisa envolveu aspectos de gênero, etnia e idade de cada um dos voluntários. Os resultados foram comparados com estimações obtidas por Bioimpedância e por Adipometria e apresentaram alta correlação. O Scanner antropométrico apresentou suas medições com certas vantagens, comparado a outras técnicas, principalmente em relação à simplificação de procedimentos com o paciente para se obter medições confiáveis. / The present paper shows the research done in the improvement of a method to estimate the body fat mass using an anthropometric Scanner AllBodyScan3D® (São Carlos, SP, 2012) that builds up 3D images from the human body. Computational procedures for body composition analysis have been developed at USP. The present study has considered measurements in different groups of volunteers, in a way that it can lead to satisfactory coverage, with relatively low error, improving the approach. The research has considered gender, ethnics and age of each volunteer. The results were compared to estimations from Bioimpedance and Adipometry and they presented high correlation. The anthropometric Scanner has shown some advantages in comparison to other techniques, mainly due to its simplified procedures imposed on patients for obtaining reliable measures.
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Apports des biomarquers amyloïdes dans la caractérisation de la plainte mnésique du sujet âgé / Contribution of amyloid biomarkers for characterizing memory complaints in older adultsLilamand, Matthieu 11 October 2017 (has links)
Les biomarqueurs de la maladie d’Alzheimer (MA) permettraient d’identifier les processus pathologiques de la maladie plusieurs années avant l’apparition des premiers signes cliniques. Ainsi, la tomographie par émission de positons (TEP) reposant sur les radio-traceurs liant les plaques amyloïdes, a ouvert de nouvelles perspectives en matière d’identification précoce de la maladie, in vivo, très en amont des premiers symptômes. Cependant, l’utilisation de ces biomarqueurs est restée limitée à de faibles effectifs de sujets, rarement suivis au-delà de quelques mois et le coût important de ces outils nous autorise à étudier leurs performances au regard des batteries de tests cognitifs et fonctionnels dont nous disposons. L’objectif général de ce travail était d’évaluer l’intérêt de l’utilisation du TEP scanner amyloïde au sein d’une population parfaitement phénotypée de sujets âgés présentant une plainte mnésique associée ou non à des signes cliniques objectifs. Notre population d’étude était constituée de 271 participants de l’essai MAPT âgés de 70 ans et plus, sans troubles cognitifs majeurs, ayant réalisé un TEP scanner amyloïde. Dans un premier travail, nous avons comparé les caractéristiques socio-démographiques et cliniques des sujets selon la présence ou non de plaques amyloïdes et d’une atteinte de la mémoire épisodique. Dans un second travail, nous avons analysé l’association transversale entre la charge amyloïde cérébrale et les performances pour les activités instrumentales de la vie quotidienne (IADL). Enfin, dans un troisième travail, nous avons comparé l’évolution des performances pour les IADL au cours des trois années de suivi en fonction de la charge amyloïde cérébrale.Les sujets avec une charge amyloïde positive au TEP présentaient de moins bonnes performances pour les IADL que ceux ayant un scanner négatif, en dépit d’un fonctionnement cognitif comparable. La présence de plaques amyloïdes cérébrales était associée à une évolution défavorable des performances pour les IADL, malgré la prise en compte de l’âge, du groupe d’intervention dans l’essai MAPT et du génotype ApoE. Notre travail montre que la présence de plaques amyloïdes cérébrales chez des sujets ayant une plainte mnésique est systématiquement associée à une moindre capacité à réaliser les activités complexes du quotidien malgré l’absence de troubles cognitifs avérés. Néanmoins, l’absence de traitement curatif de la MA et l’incertitude quant à l’évolution à long terme des sujets asymptomatiques présentant une anomalie isolée d’un biomarqueur motivent la réalisation d’autres études longitudinales, ciblées sur les sujets les plus âgés. / The biomarkers of Alzheimer’s disease (AD) have enabled the identification of its pathological features, many years before the onset of clinical symptoms. Positon Emission Tomography (PET) using radiotracers binding the amyloid plaques has, indeed, paved the way for new perspectives. However, these biomarkers have only been studies in small populations so far, with limited follow-up. Moreover, their high costs allow us to question their performances in view of their relationship to physical and cognitive assessment instruments. The main goal of our work was to assess the interest of amyloid PET in a well-phenotyped population of elderly subjects reporting memory complaints, associated with objective cognitive impairment or not. Our studied population comprised 271 participants from the MAPT trial aged 70 and over, without major cognitive impairment, who performed amyloid PET examination. The first analysis studied the socio-demographical and clinical characteristics of individuals depending on the presence of brain amyloid deposition or episodic memory impairment. A second study examined the cross-sectional association between brain amyloid load and Instrumental Activities of Daily Living (IADL) performance. The last analysis focused of the longitudinal change in IADL abilities between amyloid positive and amyloid negative participants over the 3-year follow-up.Amyloid positive subjects showed poorer abilities in IADL compared to their amyloid negative counterparts, despite similar cognitive performance. Brain amyloid load also impacted the daily functioning of individuals over time, taking in consideration confounding factors such as age, randomization group and ApoE genotyping. These findings confirmed the relationship of brain amyloid deposition to subtle changes in IADL abilities, even in the absence of cognitive impairment. Yet, the absence of disease modifying agents as well as uncertainties regarding the long-term evolution of asymptomatic individuals showing a positive biomarker are still to be determined. Further longitudinal studies including older old participants are warranted to address these concerns.
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A Self-Configuring 3-D Body ScannerHoltkamp, David James 10 June 2009 (has links)
No description available.
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3D Scanner : Scanning small objects and recreating them visually as a mesh in a computer / 3D-ScannerEgenäs, Carl, Sacilotto, Axel January 2021 (has links)
The purpose of this project was to construct a 3D scanner capable of scanning smaller objects and visualize them in a computer with satisfying accuracy. The goal was then to generate an STL file able to be 3D printed in an attempt at reverse engineering. Components, materials and tools were provided by KTH to the best of their ability and abudget of 1000 SEK was given to purchase components not available at KTH. The scanner was designed using Solid Edge and utilizes two stepper motors to scan objects. One motor is used to rotate a platform that the object is placed upon and the second stepper motor is used to move an elevator on which a distance sensor is mounted. By keeping track of the elevator’s height in conjunction with the rotation of the object, the distance measured by the sensor can be converted into a point in a Cartesian coordinate system. Several different methods were tested in order to see how results varied. Firstly, the density of scanned points was increased, meaning that the sensor returned values more often as the stepper motor was rotating. Secondly, multiple measurements were made for a single point to determine an average distance and in that way reduce noise and uncertainty. Placing a single laser sensor perpendicular to the object rotating plate proved to be the optimal arrangement in terms of accuracy with the limited budget provided for this project. The scans are very time consuming which makes it important to decide whether to prioritize speed or accuracy. / Syftet med detta projekt var att konstruera en 3D-scanner kapabel att scanna mindre objekt och visualisera dem i en dator med tillfredsställande resultat. Målet var sedan att generera en STL-fil som går att skriva ut i 3D-skrivare för att försöka använda sig av reverse engineering. Komponenter, material och verktyg försågs av KTH så gott det gick och en budget på 1000 kr var tillgänglig för att inhandla komponenter som inte fanns på KTH. Skannern designades med hjälp av Solid Edge och använder sig av två stegmotorer för att skanna object. En motor användes för att rotera den plattform som objektet placerades på och den andra stegmotorn användes för att flytta en hiss varpå en avståndssensor monterades. Genom att hålla koll på hissens höjd i kombination med rotationen av objektet kan avståndet som sensorn uppmäter konvertera still en punkt i det kartesiska koordinatsystemet. Ett flertal metoder testades för att undersöka hur resultaten varierade. För det första ökades densiteten av skannade punkter, det vill säga sensorn returnerade värden oftare än stegmotorn roterade. För det andra genomfördes ett flertal mätningar för varje enskild punkt för att bestämma ett medelavstånd och på så sätt minimera brus och osäkerhet. Att placera en enstaka lasersensor vinkelrätt mot objektroterande plattan visade sig vara det optimala arrangemanget för noggrannhet med den begränsade budgeten för det här projektet. Inskanningarna är väldigt tidskrävande vilket gör det viktigt att bestämma sig för att prioritera snabbhet eller noggrannhet.
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AN INNOVATIVE APPROACH TO A PERFORMANCE ENHANCEMENT MODIFICATION OF A TWO AXIS TELEMETRY TRACKING SYSTEMRichard, Gaetan C., Gonzalez, Daniel G. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The design of a telemetry tracking system is generally centered around its desired RF
performance which is typically specified in terms of beamwidth, gain and/or G/T.
These parameters determine the size of the reflector used in a given application and
consequently dictate the required size and performance of the associated pedestal.
Any subsequent improvement in the RF performance of such a system is primarily
achieved by increasing the size of its reflector. The magnitude of the improvement
realized is therefore limited by the load handling capability of the pedestal. In most
instances, the substitution of a larger reflector with its increased inertia and wind
loading causes a significant degradation in the dynamic performance of the tracking
system.
This paper describes how the figure of merit (G/T) of a specific dual axis telemetry
tracking system can be improved by a minimum of 7.3 dB/K° without impacting its
dynamic performance or increasing its weight.
These impressive results are made feasible by the innovative pairing of a unique
design planar reflector with a novel implementation of the conical scanner technology.
The FLAPS™ reflector incorporates a newly developed concept which features
lightweight construction and very low wind load coefficients [1, 2]. The conical
scanner is a lightweight version of the DECS tracking feed system described in the
referenced technical paper [3].
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Élaboration d'une méthodologie de relevé d'objets architecturaux <br />Contribution basée sur la combinaison de techniques d'acquisitionAlby, Emmanuel 23 November 2006 (has links) (PDF)
Le relevé extérieur d'ouvrage architectural est le moyen de créer une représentation du bâtiment dans son état de conservation. Deux techniques d'acquisition à distance se distinguent par leur efficacité et la qualité des données produites : la photogrammétrie et le balayage optique. Ces deux techniques sont soumises aux règles de l'optique et ne permettent pas de mesurer les parties invisibles de l'objet. La combinaison des techniques peut améliorer la qualité des données, mais il subsiste toujours des zones non mesurées et de ce fait non représentables. Pour palier ce problème, nous émettons l'hypothèse que l'usage de connaissances architecturales peut permettre de recomposer les parties manquantes lors de la modélisation. Cette thèse propose un processus basé sur la combinaison de ces deux techniques et sur l'intégration des connaissances architecturales accessibles depuis la documentation écrite ou encore par les règles de construction des édifices. La complexité d'un ouvrage architectural et la multitude des données imposent une division de la modélisation en plusieurs étapes identifiables. Nous proposons de découper le processus de modélisation selon le mode de figuration des niveaux de détail utilisé pour la représentation de l'architecture. Les niveaux différents de détail permettent d'obtenir des étapes de modélisation clairement indentifiables, mais aussi un processus progressif où les informations peuvent être utilisées au fur et à mesure. Notre approche intègre ainsi les données dimensionnelles à la documentation architecturale, pour permettre la mise en place d'un processus de modélisation afin d'obtenir un modèle le plus complet possible
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Three essays on differentiated products and heterogeneous consumer preferences: the case of table eggsHeng, Yan January 1900 (has links)
Doctor of Philosophy / Department of Agricultural Economics / Hikaru Hanawa Peterson / Consumers’ food demand has been found to be affected not only by prices and income, but also by their increasing concern about factors like health benefits, animal welfare, and environmental impacts. Thus, many food producers have differentiated and advertised their products using relevant attributes. The increasing demand and supply of differentiated food products have raised questions regarding consumer preferences and producer strategies. This dissertation consists of three essays and empirically examines the egg market to shed light on related issues.
The first question that this study aims to answer is whether consumers are willing to pay a premium for livestock and dairy products associated with improved animal welfare. Consumers’ attitude towards such products not only affect manufacturers’ production decisions, but also influence policy makers and current legislations. Using a national online survey with choice experiments, the first essay found that consumers in the study sample valued eggs produced under animal-friendly environment, suggesting incentives for producers to adopt animal welfare friendly practices.
In an actual shopping trip, consumers usually need to choose from products with multiple attributes and labels. Studying how consumers with heterogeneous preferences process these information simultaneously and make decisions is important for producers to target interested consumer segments and implement more effective labeling strategies. In the second essay, a different national online survey was administered. The analysis using a latent class model categorized the sample respondents into four classes, and their preferences toward attributes and various label combinations differed across classes.
Scanner data, which record actually purchased choices, are an important source of information to study consumer preferences. Diverging from the traditional demand approaches that are limited in studying differentiated product markets using scanner data, this study used a random coefficient logit model to overcome potential limitations and examine the demand relationship as well as price competition in the differentiated egg market. The third essay found that conventional and private labeled eggs yielded higher margins due to less elastic demand and cautioned producers of specialty eggs, which are usually sold at high prices despite their much more elastic demand.
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Development of Laser System to Measure Pavement RuttingWang, Hongzhi 20 October 2005 (has links)
Asphalt pavement rutting is one of the most common and destructive pavement distresses observed on U.S. roads, particularly in the urban environment at intersections. They are an important indicator of the structural integrity of the pavement as well as having an impact on road user safety. For these reasons, most road agencies regularly monitor the levels of rut depths on their pavement. There are four technologies used for estimating rut depth in automated measurement way: ultrasonics, point lasers, scanning lasers, Optical.
This thesis will focus on the development of the laser scanner rut depth measurement system, including the improvement of the hardware design, the software development and data analysis.
In order to evaluate the accuracy and correction of the laser scanner system, the researcher used it to measure different pavement in different situations. This research focused on the performance measures, such as correlativity, repeatability.
From field experiments and data analysis, the following results had been obtained:
1. Laser scanner showed satisfactory repeatability performances;
2. Laser scanner has good correlations with manual rut data.
3. High power laser scanner in dark asphalt has good correlations with in light pavement.
The findings of this research will contribute to the development of laser system in the measurement of pavement rutting.
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Evaluation of an airborne thermal scanner (8-12 µm) as an irrigation scheduling tool for cotton (Gossypium hirsutum)Malouf, Christopher P., n/a January 1996 (has links)
Water is Australia's most precious natural resource. The quality, quantity and
availability of this resource is the single factor most limiting agricultural development and
sustainability in this country.
Since the development of Australia's cotton industry in the 1960's, and the expanding
areas of irrigated crop, there has been an increasing demand placed on the limited water
resources of the country. Consequently, the cotton industry has been the target of protest from
conservation groups, residents of rural townships and others farmers engaged in competing
rural sectors. Therefore, cotton farmers need to develop best practice in terms of water use
efficiency. Not only does this make good ecological sense but also good economic sense.
Traditional methods of irrigation scheduling have proven to be subjective and haphazard.
Recently developed methods, while providing more quantitative techniques, do not give a
synoptic view of a field's or region's crop moisture status.
The main objective of this project was to evaluate an airborne thermal scanner (8-12 µm) as practical tool for monitoring the water requirements of an irrigated cotton crop. The
thermal scanner was mounted below a light aircraft and imagery was collected over Field 86 ,
Togo Station, north-west NSW during the summer of 1990/91. The field was divided into
nine treatments for the purpose of this project. Three irrigation regimes (early, normal and
late) with three repetitions were applied to the nine treatments.
A total of fourteen images were selected for analysis. These images were grouped into
sets of AM images, PM images as well as diurnal groupings which were interpreted for three
separate dates during the growing season. Ground based measurements of infrared crop
surface and soil temperature, soil moisture deficit, leaf area index (LAI) and the Crop Water
Stress Index (CWSI) were collected to calibrate the airborne imagery.
Imagery was in the first instance visually interpreted to determine what information
could be gained from this technique. Patterns on the imagery were related to diurnal
variations in soil and crop temperatures. This investigation revealed a number of soil related
phenomena inherent to the field which were influencing the airborne detected temperatures.
While this technique showed variability across the field, the interpretation was somewhat
subjective.
Temperature values were extracted from the imagery in order to conduct an analysis
of variance (ANOVA) between the airborne and ground measurements of infrared crop
surface temperature. In summary, this analysis did not show a strong relationship between the
airborne and ground based measurements. A number of contributing factors have been
proposed as the reason for this variation in the two datasets. Pearson's correlation analysis
was applied to the AM (r = 0.65) and PM (r = 0.32) groups of airborne and ground
temperatures.
Airborne derived calculations of the CWSI were compared to ground based
measurements for the AM group of flights. These derived values were only acceptable in
instances where the ANOVA results had shown them to approximate the ground based
measurements.
While airborne thermal imagery provides a useful tool for determining general
variations in temperatures across a field, there are many additional factors, the most dominant
being the thermal characteristics of the background soil, which influence the detected
temperatures. This technique does not provide the precise quantitative information required
to accurately determine across-field measurement of the CWSI.
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