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Slagen om Fallujah, luftmakt och den nekande operationskonstenWestbom, William January 2016 (has links)
The two battles for Fallujah took place in 2004. Earlier research states that air power was a key reason for the success following the second operation, and as a critical omission during the first operation. Following this statement that air power changed the way urban operations should be conducted it should be possible to use an air power theory to explain the different outcomes of the battles. The purpose of this study is to see if Robert Pape’s theory of denial strategy is applicable as an explanation for the two operations differences of outcome. The method used for this study is a comparative case study of the two operations in which the operations are compared by analysing then using the framework of Pape’s theory. The result of this study shows that the outcomes partly can be explained from Pape’s theory, but the results differ between the two components which leads to a discussion of what this means for the theory. The result contributes to the existing research and gives reason for criticism of the earlier research which states that it was Close Air Support (CAS) that was successful during the second operation. This study shows that CAS was mostly used during the first operation and only partly used during the second, successful, operation. This study states that it was the use of operative interdiction, one of the three components of Pape’s theory, which led to the second operations success.
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Modes d’exposition au xénon-133 dans un bâtiment réacteur / Exposure mode study to xenon-133 in a reactor buildingPerier, Aurélien 14 October 2014 (has links)
Le travail décrit dans cette thèse porte sur l’évaluation du mode d’exposition externe et interne au xénon-133. Ce radionucléide est un des principaux produits de fission du combustible des réacteurs nucléaires. En cas de défaut de gaine combustible, le xénon-133 peut potentiellement exposer le personnel lors de ses interventions dans le bâtiment réacteur. En dosimétrie, les simulations Monte-Carlo sont des outils adaptés pour simuler le transport des rayonnements ionisants dans la matière. A partir des critères de radioprotection actuels, nous avons développé de nouvelles méthodes afin d’améliorer notre compréhension de l’exposition externe et interne auxénon-133 à l’intérieur d’un bâtiment réacteur. Ces nouvelles approches sont basées sur l’utilisation d’un fantôme anthropomorphe, d’une géométrie réaliste de bâtiment réacteur, de simulations Monte-Carlo GEANT4 et de modèles en compartiments. L’exposition externe dans un bâtiment réacteur a été menée en retenant un scénario d’exposition réaliste et conservatif. Nous avons quantifié le débit de dose efficace et le débit de dose équivalente au cristallin. L’exposition interne se produit lorsque le xénon-133 est inhalé. Les poumons sont les premiers organes exposés par l’inhalation du xénon-133, leur débit de dose équivalente a été quantifié. Un modèle biocinétique a été utilisé pour évaluer l’exposition interne au xénon-133. Cette thèse a permis de quantifier les grandeurs dosimétriques liées aux modes d’exposition externe et interne au xénon-133, d’étudier l’impact des changements de limites dosimétriques introduits par la Commission Internationale de Radioprotection prochainement retranscrits dans la réglementation française, et de comprendre la cinétique du xénon-133 dans le corps humain. Nous avons montré que les grandeurs dosimétriques sont nettement inférieures aux limites dosimétriques de la réglementation actuelle et future. / The work described in this thesis focuses on the external and internal dose assessment to xenon-133. During the nuclear reactor operation, fission products and radioactive inert gases, as ¹³³Xe, are generated and might be responsible for the exposure of workers incase of clad defect.Particle Monte Carlo transport code is adapted inradioprotection to quantify dosimetric quantities.The study of exposure to xenon-133 is conducted byusing Monte-Carlo simulations based on GEANT4, ananthropomorphic phantom, a realistic geometry of thereactor building, and compartmental models.The external exposure inside a reactor building isconducted with a realistic and conservative exposurescenario. The effective dose rate and the eye lensequivalent dose rate are determined by Monte-Carlosimulations. Due to the particular emission spectrum ofxenon-133, the equivalent dose rate to the lens of eyesis discussed in the light of expected new eye doselimits.The internal exposure occurs while xenon-133 isinhaled. The lungs are firstly exposed by inhalation, andtheir equivalent dose rate is obtained by Monte-Carlosimulations. A biokinetic model is used to evaluate theinternal exposure to xenon-133.This thesis gives us a better understanding to thedosimetric quantities related to external and internalexposure to xenon-133. Moreover the impacts of thedosimetric changes are studied on the current andfuture dosimetric limits. The dosimetric quantities arelower than the current and future dosimetric limits.
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Georeferering av ortofoto med UAV : En jämförelsestudie mellan direkt och indirekt georefereringAbdi, Joan, Joel, Johansson January 2020 (has links)
UAV (Unmanned Aircraft Vehicle) har revolutiontionerat ortofotoframställningen med sitt bidrag till ökad säkerhet, lägre kostnader samt effektivare arbetsgång vid framställning av ortofoton. Den traditionella flygfotogrammetrin med flygplan och utplacering av flygsignaler har varit den givna metoden i många år. Att flyga med UAV istället för flygplan sparar tid och pengar däremot är utplacering och inmätning av flygsignaler fortfarande tidskrävande och därför kostsamt. Företaget DJI har tagit fram en ny UAV med namnet DJI Phantom 4 RTK vilken stödjer möjligheten att använda satellitbaserad positionering för direkt georeferering. Den här studien har jämfört två olika georefereringsmetoder för framställning av ortofoton med UAV: direkt georeferering med NRTK (satellitbaserad positionering och nätverks-RTK) samt indirekt georeferering med olika antal markstödspunkter. Studien utfördes vid Högskolan i Gävle på en yta av åtta hektar. En undersökning av avvikelser i plan och höjd resulterade i acceptabla värden enligt de riktlinjer som följdes i HMK – Ortofoto (2017) samt de kontroller som genomfördes enligt SIS-TS 21144:2016. RMS-värdet i plan för den indirekta georefereringsmetoden ligger på 0,0102m. För den direkta georefereringsmetoden ligger RMS-värdet i plan vid användning av markstödpunkter mellan 0,0132 och 0,0148 m. Slutligen för den direkta georefereringsmetoden utan markstödpunkter är RMS-värdet i plan på 0,0136 m. RMS i höjd ligger inom intervallet 0,008-0,025 m. Det som redovisas i studien visar att en accepterad kvalitet av ortofoton går att erhålla baserat på de RMS-värden i plan och höjd med samtliga georefereringsmetoder som testats. Efter genomförda kontroller och utvärdering av de resultat kan det konstateras att de olika georefereringsmetoderna skiljer inte mycket åt varandra kvalitetsmässigt.Dock är den direkta georefereringsmetoden utan markstödpunkter mycket effektivare ur ett tidsperspektiv. Phantom 4 RTK är ny på marknaden och det behöver utföras mer forskning för att få en större insikt av dess potential. Dock krävs det mer forskning kring direkt georeferering för utvärdering av orotofotons kvalitet. / UAV (Unmanned Aircraft Vehicle) has revolutionized the creation of orthophotos with its contribution to increased safety, lower costs and more effective ways when making orthophotos. The traditional aerial photogrammetry with airplanes and placement of flight signals has been the standard method for years. To fly with UAV instead of an airplane is cheaper and saves time, however, the placement and measurements of flight signals is still time consuming and therefore expensive. The company DJI has developed a new UAV called Phantom 4 RTK that supports satellite based technology for direct georeferercing. This study compared two different measuring methods when producing orthophotos with UAV: direct georeferencing with NRTK (Network Real Time Kinematic) and indirect georeferencing when using different number of Ground Control Points (GCP). The study was conducted at the University of Gävle over an area of eight hectares. An investigation of the deviation in plane and height resulted in acceptable units based on the guidelines that were followed in HMK – Ortofoto and the controls that were followed from SIS- TS 21144:2016. The RMS value in plane for the indirect georeferencing method is 0,0102 m. For the direct georeferencing method the RMS value in plane when using ground control points is between 0,0132 and 0,0148 m. At last the RMS value for the direct georeferencing method without ground control points is 0,0136m. The RMS value in height is between the intervals 0,008-0,025 m. The data presented in this study show that an accepted quality in the orthophotos can be acquired based on the RMS values in plane and height for every georeferencing that was tested. After accomplished controls and evaluation the results show that the different georeferencing methods doesn´t differantiate too much from each other based on their quality. However, the direct georeferencing method with ground control points is more effective from a time perspective. Phantom 4 RTK is new on the market and more research is necessary in order to understand the potential of this technology and its posibility to integrate into society. More research is recquired for the direct georeferencing method in order to evaluate the quality of orthophotos.
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Patienters upplevelse av att förlora en extremitet : En litteraturöversikt / Patients' experience of losing an extremityJohansson, Lena, Spång, Maria January 2020 (has links)
I Sverige utförs amputationer vanligtvis till följd av nedsatt blodcirkulation. Efter amputation kan fantomsmärta och andra problem uppstå, vilket kan påverka livskvalitén. Syftet med den här litteraturöversikten är att beskriva patienters upplevelse av livskvalitén i det dagliga livet efter att ha fått en nedre extremitet amputerad. Litteraturöversikten är en studentuppsats på kandidatnivå där tio artiklar granskades. Resultatet visade tre huvudteman med tillhörande underteman som beskriver patienters upplevelse av livskvalitén i det dagliga livet efter amputation. Huvudteman som framkom var: Vården före och efter, livskvalité och hopp inför framtiden. Resultatet av litteraturöversikten visade på att patienter upplevde sig inte vara delaktiga i besluten och vården efter amputation. De upplevde även att fantomsmärtan påverkade livskvalitén samt att de efter amputation upplevde förlorad självständighet och att självbilden förändrades. Positiva upplevelser efter amputation påverkades av huruvida patienter accepterade sin nya situation. De som led av långvarig smärta före amputation kunde se ingreppet som en räddning till att leva ett smärtfritt liv. Sjuksköterskor bör arbeta individanpassat, möta patienters livsvärld och samverka i team för att underlätta möjligheterna att finna livskvalité samt förbättra möjligheten till återhämtning. / In Sweden, amputations are usually performed as a result of reduced blood circulation. After amputation, phantom pain and other problems can occur, which can affect the quality of life. The purpose of this literature review is to describe patients' experience of the quality of life in daily life after having a lower extremity amputated. The literature review is a student essay at the bachelor's level where ten articles were reviewed. The results showed three main themes with associated sub-themes that describe patients' experience of the quality of life in daily life after amputation. The main themes that emerged were: Care before and after, quality of life and hope for the future. The results of the literature review showed that patients did not feel involved in the decisions and care after amputation. They also experienced that phantom pain affected the quality of life and that after amputation they experienced lost independence and that their self-image changed. Positive experiences after amputation were affected by whether patients accepted their new situation. Those who suffered from prolonged pain before amputation could see the procedure as a salvation to live a pain-free life. Nurses should work individually, meet patients' worlds of life and collaborate in teams to facilitate the opportunities to find quality of life and improve the possibility of recovery.
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The dentistry students’ experiences of training with Simodont® compared to traditional pre-clinical training.Saeed, Shahad, Abdulrahman, Yaman January 2021 (has links)
Background Virtual reality simulators have added a more realistic aspect of the preclinical dental training. They have been used to enable a smooth transition from the preclinical to clinical training and thus increased patient safety. However, the effect of an additional training using these virtual reality simulators remain unclear. Aim To examine the 2nd- and 3rd-year dentistry students’ experiences of training with Simodont® and to compare their preparation performances with those of a control group with traditional pre-clinical training only. Methods A group of 2nd-year dental students performed drilling exercises on Simodont® while another group of 3rd-year dental students had a trepanation exercise on Simodont®. Their performances were assessed and their answers of the questionnaires were compared with a control group from the same grade that had not been allowed any additional training on the Simodont®. Results The 2nd-year Simodont participants showed up to 40% improved performance in their final manual test results compared to their test results from baseline. The 3rd-year Simodont participants showed unchanged manual results after the additional training on the Simodont®. According to the questionnaire, 89% of both 2nd- and 3rd- year of Simodont participants did not think that Simodont® should replace traditional preclinical training. Conclusions The 2nd-year Simodont participants felt more confident about performing the final drilling test than the control group. However, the Simodont group of the 3rd-year dental students felt less confident about performing the final trepanation test compared to the control group according to the questionnaire.
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A Phantom Based Comparison of Image Segmentation Algorithms for Adaptive Functional Volume Determination of the Thyroid Gland using SPECTBerg, Henrik January 2021 (has links)
Background One of the most used treatments for hyperthyroidism, is therapy with radioactive iodine (131I), which is accumulated in the thyroid gland. To determine the activity of 131I to be administered for a certain absorbed dose, the volume of the gland is of great importance but the historically used methods for estimating the functional volume of the gland are based on large approximations. The use of SPECT images enables increased accuracy of functional volume determination. However, there is a need for more realistic phantom studies and improved image segmentation. Aim The aim of this thesis was to find a robust method for image segmentation of the thyroid gland that could adapt to various object sizes and contrasts. The aim was also to develop an accessible and flexible 3D thyroid phantom for measurements and optimisation of parameter settings. Materials and Methods Thyroid phantoms made from playdough loaded with 99mTcO4-, were placed in a neck phantom filled with 99mTcO4- solution of various concentration. SPECT and CT acquisitions of the phantoms were performed and the SPECT images were segmented using thresholding and region growing algorithms. The thresholds in the segmentation algorithms were optimised by minimisation of cost functions consisting of Dice score, against the CT-volume, and relative SPECT volume. To find thresholds that could be used on all phantom volumes and image backgrounds, two overall cost functions were optimised for high and low backgrounds respectively. The optimised thresholds were validated on another set of playdough phantoms. They were also used on a simpler plastic can phantom for comparison of the performance relative to the method used in the clinic today. Results The optimised thresholds showed a substantial divergence between the measurements, ranging from 40 to 58 % for the thresholding algorithm and from 8 to 19 % for the region growing algorithm. The overall optimised thresholds were 55 and 48 % for high and low image backgrounds for the thresholding algorithm which was selected for the validation measurements due to its lower overall cost function and high stability. The developed method indicated a higher accuracy in functional volume determination of the thyroid gland than the standard method used. Conclusions An image segmentation method for functional volume determination of the thyroid gland, that can adapt to image contrast, was developed in this thesis. The method indicates an improved accuracy for functional volume determination of thyroid glands, but more experiments would need to be conducted. The developed thyroid phantoms enable further optimisation of image segmentation parameters for various object sizes, contrasts and shapes. The results indicate that thresholds deduced from simpler phantoms may be too uncertain which might lead to overtreatment of hyperthyroidism with 131I. It was also indicated that thresholding is more suitable than region growing for image segmentation of SPECT images.
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Akvizice MRI obrazových sekvencí pro preklinické perfusní zobrazování / MRI Acquisition of Image Sequences for Preclinical Perfusion ImagingKrátká, Lucie January 2012 (has links)
The task of this thesis is to study methods for the acquisition perfusní imaging based on dynamic MR imaging with T1 contrast. It describes methods of measurement of T1 relaxation time and the possibility of evaluating the results. It further describes the phantoms and their use. And it is here mentioned for the dynamic acquisition protocol perfusní imaging. There is also described in detail created a program for automatic control of the NMR system. In the experimental measurements are performed on static and dynamic phantom, are also evaluated perfusion parameters from the Flash sequence.
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Vliv MR pulsních sekvencí na teplotu měřeného objektu / The effect of the MR pulse sequences on the measurement object temperatureKosková, Markéta January 2016 (has links)
This paper deals with the effect of the MR pulse sequences on the temperature of the measured object. The theoretical part is dedicated to basic principle of magnetic resonance, the selected pulse sequences and risks that are connected with MRI. There is also described the draft of the testing phantom and information about the measurement and record of temperature during MR measurement. In the experimental part the effect of RF coils, pulse sequences and parameters of pulse sequences are tested on drafted phantom with experimental MR device located at the Institut of Scientific Instruments of the AS CR in Brno. These findings are then tested on live laboratory mouse. All results are analyzed and used as default data for developed simulation program.
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Kombinerade vapens förutsättningar i skilda miljöerJonsson, Tova January 2020 (has links)
Different prerequisites for war exists and varies due to the terrain. Cities, mountains and covered terrain all creates their special conditions for the battle. The biggest difference in methods is found between the urban warfare and all the other ways of fighting in war. Combined arms constitutes the fundamentals of fighting a war, and organizing armed forces. But if the environment of the war is changing, the different prerequisites of combined arms need to change. The purpose of this study is to survey the distinguishing differences and prerequisites between the two kinds of environments, described in the invasion and fight in Rumaila oil field (2003) and Operation Phantom Fury (2004). By analyzing these cases, the purpose of this theory consuming case study is to explore and examine the use of combined arms in different environments during the Iraqi war in between 2003 and 2004. The analytical results reveal that the prerequisites before Operation Phantom Fury that made the operation successful was premonition to all the civilians in the city of Fallujah, the aggressive and massive use of indirect fire support, the reorganization of the divisions backbone, infantry, and finally the knowledge from earlier operations in Fallujah.
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Hur kan framgång i strid i bebyggelse uppnås på taktisk nivå? : En teoriprövande fallstudie av Alice Hills teoriNorbäck, Alexander January 2021 (has links)
The world is rapidly becoming more urbanised and with key infrastructure being located inside or close to cities the probability of urban warfare in the next major conflict is very high. This thesis examines how the use of Alice Hills theory can explain success in urban warfare on the tactical level of war. The purpose of the thesis is to test the validity of Hills theory. To examine to what extent Hills’s theory can explain the success of the coalition forces during Operation Phantom Fury and the failure of Operation Vigilant Resolve, a theory testing case study is applied. The two cases have similar background variables, which allows for a structured comparison of the two cases. The analysis is based on Hills’s success factors in urban warfare. The results of the analysis reveal that Hills theory can explain the success of the coalition during Operation Phantom Fury and the failure of Operation Vigilant Resolve, thereby strengthening the validity of Hills theory. The results highlight the need to control the civilian population during urban combat. However, due to the difficulties of measuring success factors such as leadership and morale with the chosen method, the external validity of the results is negatively affected.
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